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/linux-master/fs/xfs/libxfs/
H A Dxfs_rmap_btree.hdiff 0ed5f735 Thu Sep 23 11:32:06 MDT 2021 Darrick J. Wong <djwong@kernel.org> xfs: compute absolute maximum nlevels for each btree type

Add code for all five btree types so that we can compute the absolute
maximum possible btree height for each btree type. This is a setup for
the next patch, which makes every btree type have its own cursor cache.

The functions are exported so that we can have xfs_db report the
absolute maximum btree heights for each btree type, rather than making
everyone run their own ad-hoc computations.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_errortag.hdiff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 9b247179 Thu Feb 07 11:37:16 MST 2019 Darrick J. Wong <darrick.wong@oracle.com> xfs: cache unlinked pointers in an rhashtable

Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.

The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.

FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:

+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s

real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt

real 0m0.050s
user 0m0.004s
sys 0m0.030s

And without the patch:

+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s

real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt

real 0m0.086s
user 0m0.000s
sys 0m0.060s

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
H A Dxfs_sb.hdiff 881f78f4 Mon Jan 29 21:27:23 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: remove conditional building of rt geometry validator functions

I mistakenly turned off CONFIG_XFS_RT in the Kconfig file for arm64
variant of the djwong-wtf git branch. Unfortunately, it took me a good
hour to figure out that RT wasn't built because this is what got printed
to dmesg:

XFS (sda2): realtime geometry sanity check failed
XFS (sda2): Metadata corruption detected at xfs_sb_read_verify+0x170/0x190 [xfs], xfs_sb block 0x0

Whereas I would have expected:

XFS (sda2): Not built with CONFIG_XFS_RT
XFS (sda2): RT mount failed

The root cause of these problems is the conditional compilation of the
new functions xfs_validate_rtextents and xfs_compute_rextslog that I
introduced in the two commits listed below. The !RT versions of these
functions return false and 0, respectively, which causes primary
superblock validation to fail, which explains the first message.

Move the two functions to other parts of libxfs that are not
conditionally defined by CONFIG_XFS_RT and remove the broken stubs so
that validation works again.

Fixes: e14293803f4e ("xfs: don't allow overly small or large realtime volumes")
Fixes: a6a38f309afc ("xfs: make rextslog computation consistent with mkfs")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 881f78f4 Mon Jan 29 21:27:23 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: remove conditional building of rt geometry validator functions

I mistakenly turned off CONFIG_XFS_RT in the Kconfig file for arm64
variant of the djwong-wtf git branch. Unfortunately, it took me a good
hour to figure out that RT wasn't built because this is what got printed
to dmesg:

XFS (sda2): realtime geometry sanity check failed
XFS (sda2): Metadata corruption detected at xfs_sb_read_verify+0x170/0x190 [xfs], xfs_sb block 0x0

Whereas I would have expected:

XFS (sda2): Not built with CONFIG_XFS_RT
XFS (sda2): RT mount failed

The root cause of these problems is the conditional compilation of the
new functions xfs_validate_rtextents and xfs_compute_rextslog that I
introduced in the two commits listed below. The !RT versions of these
functions return false and 0, respectively, which causes primary
superblock validation to fail, which explains the first message.

Move the two functions to other parts of libxfs that are not
conditionally defined by CONFIG_XFS_RT and remove the broken stubs so
that validation works again.

Fixes: e14293803f4e ("xfs: don't allow overly small or large realtime volumes")
Fixes: a6a38f309afc ("xfs: make rextslog computation consistent with mkfs")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 881f78f4 Mon Jan 29 21:27:23 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: remove conditional building of rt geometry validator functions

I mistakenly turned off CONFIG_XFS_RT in the Kconfig file for arm64
variant of the djwong-wtf git branch. Unfortunately, it took me a good
hour to figure out that RT wasn't built because this is what got printed
to dmesg:

XFS (sda2): realtime geometry sanity check failed
XFS (sda2): Metadata corruption detected at xfs_sb_read_verify+0x170/0x190 [xfs], xfs_sb block 0x0

Whereas I would have expected:

XFS (sda2): Not built with CONFIG_XFS_RT
XFS (sda2): RT mount failed

The root cause of these problems is the conditional compilation of the
new functions xfs_validate_rtextents and xfs_compute_rextslog that I
introduced in the two commits listed below. The !RT versions of these
functions return false and 0, respectively, which causes primary
superblock validation to fail, which explains the first message.

Move the two functions to other parts of libxfs that are not
conditionally defined by CONFIG_XFS_RT and remove the broken stubs so
that validation works again.

Fixes: e14293803f4e ("xfs: don't allow overly small or large realtime volumes")
Fixes: a6a38f309afc ("xfs: make rextslog computation consistent with mkfs")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 881f78f4 Mon Jan 29 21:27:23 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: remove conditional building of rt geometry validator functions

I mistakenly turned off CONFIG_XFS_RT in the Kconfig file for arm64
variant of the djwong-wtf git branch. Unfortunately, it took me a good
hour to figure out that RT wasn't built because this is what got printed
to dmesg:

XFS (sda2): realtime geometry sanity check failed
XFS (sda2): Metadata corruption detected at xfs_sb_read_verify+0x170/0x190 [xfs], xfs_sb block 0x0

Whereas I would have expected:

XFS (sda2): Not built with CONFIG_XFS_RT
XFS (sda2): RT mount failed

The root cause of these problems is the conditional compilation of the
new functions xfs_validate_rtextents and xfs_compute_rextslog that I
introduced in the two commits listed below. The !RT versions of these
functions return false and 0, respectively, which causes primary
superblock validation to fail, which explains the first message.

Move the two functions to other parts of libxfs that are not
conditionally defined by CONFIG_XFS_RT and remove the broken stubs so
that validation works again.

Fixes: e14293803f4e ("xfs: don't allow overly small or large realtime volumes")
Fixes: a6a38f309afc ("xfs: make rextslog computation consistent with mkfs")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_attr_leaf.hdiff 07120f1a Mon Jul 20 22:47:22 MDT 2020 Allison Collins <allison.henderson@oracle.com> xfs: Add xfs_has_attr and subroutines

This patch adds a new functions to check for the existence of an
attribute. Subroutines are also added to handle the cases of leaf
blocks, nodes or shortform. Common code that appears in existing attr
add and remove functions have been factored out to help reduce the
appearance of duplicated code. We will need these routines later for
delayed attributes since delayed operations cannot return error codes.

Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix a leak-on-error bug reported by Dan Carpenter]
[darrick: fix unused variable warning reported by 0day]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reported-by: dan.carpenter@oracle.com
Reported-by: kernel test robot <lkp@intel.com>
diff 0bb9d159 Tue Jan 14 15:31:49 MST 2020 Darrick J. Wong <darrick.wong@oracle.com> xfs: streamline xfs_attr3_leaf_inactive

Now that we know we don't have to take a transaction to stale the incore
buffers for a remote value, get rid of the unnecessary memory allocation
in the leaf walker and call the rmt_stale function directly. Flatten
the loop while we're at it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_ialloc_btree.hdiff 0ed5f735 Thu Sep 23 11:32:06 MDT 2021 Darrick J. Wong <djwong@kernel.org> xfs: compute absolute maximum nlevels for each btree type

Add code for all five btree types so that we can compute the absolute
maximum possible btree height for each btree type. This is a setup for
the next patch, which makes every btree type have its own cursor cache.

The functions are exported so that we can have xfs_db report the
absolute maximum btree heights for each btree type, rather than making
everyone run their own ad-hoc computations.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_bmap_btree.hdiff 0ed5f735 Thu Sep 23 11:32:06 MDT 2021 Darrick J. Wong <djwong@kernel.org> xfs: compute absolute maximum nlevels for each btree type

Add code for all five btree types so that we can compute the absolute
maximum possible btree height for each btree type. This is a setup for
the next patch, which makes every btree type have its own cursor cache.

The functions are exported so that we can have xfs_db report the
absolute maximum btree heights for each btree type, rather than making
everyone run their own ad-hoc computations.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_ialloc.hdiff 0d1b9769 Wed Apr 20 18:46:24 MDT 2022 Dave Chinner <dchinner@redhat.com> xfs: convert AGI log flags to unsigned.

5.18 w/ std=gnu11 compiled with gcc-5 wants flags stored in unsigned
fields to be unsigned.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 0e0417f3 Wed Jul 11 23:26:07 MDT 2018 Brian Foster <bfoster@redhat.com> xfs: remove dfops parameter from ifree call stack

The inode free callchain starting in xfs_inactive_ifree() already
associates its dfops with the transaction. It still passes the dfops
on the stack down through xfs_difree_inobt(), however.

Clean up the call stack and reference dfops directly from the
transaction. This patch does not change behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_iext_tree.cdiff 3f8a4f1d Thu Oct 17 14:40:33 MDT 2019 Dave Chinner <dchinner@redhat.com> xfs: fix inode fork extent count overflow

[commit message is verbose for discussion purposes - will trim it
down later. Some questions about implementation details at the end.]

Zorro Lang recently ran a new test to stress single inode extent
counts now that they are no longer limited by memory allocation.
The test was simply:

# xfs_io -f -c "falloc 0 40t" /mnt/scratch/big-file
# ~/src/xfstests-dev/punch-alternating /mnt/scratch/big-file

This test uncovered a problem where the hole punching operation
appeared to finish with no error, but apparently only created 268M
extents instead of the 10 billion it was supposed to.

Further, trying to punch out extents that should have been present
resulted in success, but no change in the extent count. It looked
like a silent failure.

While running the test and observing the behaviour in real time,
I observed the extent coutn growing at ~2M extents/minute, and saw
this after about an hour:

# xfs_io -f -c "stat" /mnt/scratch/big-file |grep next ; \
> sleep 60 ; \
> xfs_io -f -c "stat" /mnt/scratch/big-file |grep next
fsxattr.nextents = 127657993
fsxattr.nextents = 129683339
#

And a few minutes later this:

# xfs_io -f -c "stat" /mnt/scratch/big-file |grep next
fsxattr.nextents = 4177861124
#

Ah, what? Where did that 4 billion extra extents suddenly come from?

Stop the workload, unmount, mount:

# xfs_io -f -c "stat" /mnt/scratch/big-file |grep next
fsxattr.nextents = 166044375
#

And it's back at the expected number. i.e. the extent count is
correct on disk, but it's screwed up in memory. I loaded up the
extent list, and immediately:

# xfs_io -f -c "stat" /mnt/scratch/big-file |grep next
fsxattr.nextents = 4192576215
#

It's bad again. So, where does that number come from?
xfs_fill_fsxattr():

if (ip->i_df.if_flags & XFS_IFEXTENTS)
fa->fsx_nextents = xfs_iext_count(&ip->i_df);
else
fa->fsx_nextents = ip->i_d.di_nextents;

And that's the behaviour I just saw in a nutshell. The on disk count
is correct, but once the tree is loaded into memory, it goes whacky.
Clearly there's something wrong with xfs_iext_count():

inline xfs_extnum_t xfs_iext_count(struct xfs_ifork *ifp)
{
return ifp->if_bytes / sizeof(struct xfs_iext_rec);
}

Simple enough, but 134M extents is 2**27, and that's right about
where things went wrong. A struct xfs_iext_rec is 16 bytes in size,
which means 2**27 * 2**4 = 2**31 and we're right on target for an
integer overflow. And, sure enough:

struct xfs_ifork {
int if_bytes; /* bytes in if_u1 */
....

Once we get 2**27 extents in a file, we overflow if_bytes and the
in-core extent count goes wrong. And when we reach 2**28 extents,
if_bytes wraps back to zero and things really start to go wrong
there. This is where the silent failure comes from - only the first
2**28 extents can be looked up directly due to the overflow, all the
extents above this index wrap back to somewhere in the first 2**28
extents. Hence with a regular pattern, trying to punch a hole in the
range that didn't have holes mapped to a hole in the first 2**28
extents and so "succeeded" without changing anything. Hence "silent
failure"...

Fix this by converting if_bytes to a int64_t and converting all the
index variables and size calculations to use int64_t types to avoid
overflows in future. Signed integers are still used to enable easy
detection of extent count underflows. This enables scalability of
extent counts to the limits of the on-disk format - MAXEXTNUM
(2**31) extents.

Current testing is at over 500M extents and still going:

fsxattr.nextents = 517310478

Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_da_format.hdiff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
diff a49bbce5 Mon Jul 10 10:12:20 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: convert flex-array declarations in xfs attr leaf blocks

As of 6.5-rc1, UBSAN trips over the ondisk extended attribute leaf block
definitions using an array length of 1 to pretend to be a flex array.
Kernel compilers have to support unbounded array declarations, so let's
correct this.

================================================================================
UBSAN: array-index-out-of-bounds in fs/xfs/libxfs/xfs_attr_leaf.c:2535:24
index 2 is out of range for type '__u8 [1]'
Call Trace:
<TASK>
dump_stack_lvl+0x33/0x50
__ubsan_handle_out_of_bounds+0x9c/0xd0
xfs_attr3_leaf_getvalue+0x2ce/0x2e0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_leaf_get+0x148/0x1c0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get_ilocked+0xae/0x110 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_attr_get+0xee/0x150 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
xfs_xattr_get+0x7d/0xc0 [xfs 4a986a89a77bb77402ab8a87a37da369ef6a3f09]
__vfs_getxattr+0xa3/0x100
vfs_getxattr+0x87/0x1d0
do_getxattr+0x17a/0x220
getxattr+0x89/0xf0

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
/linux-master/fs/xfs/
H A Dxfs_globals.cdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff dae5cd81 Thu May 10 22:50:23 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: add mount delay debug option

Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[ 60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G D W 4.16.0-rc5-dgc #440
[ 60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[ 60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[ 60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[ 60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[ 60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[ 60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[ 60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[ 60.390827] FS: 00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[ 60.392253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[ 60.394519] Call Trace:
[ 60.395252] radix_tree_gang_lookup_tag+0xc4/0x130
[ 60.395948] xfs_perag_get_tag+0x37/0xf0
[ 60.396522] xfs_reclaim_inodes_count+0x32/0x40
[ 60.397178] xfs_fs_nr_cached_objects+0x11/0x20
[ 60.397837] super_cache_count+0x35/0xc0
[ 60.399159] shrink_slab.part.66+0xb1/0x370
[ 60.400194] shrink_node+0x7e/0x1a0
[ 60.401058] try_to_free_pages+0x199/0x470
[ 60.402081] __alloc_pages_slowpath+0x3a1/0xd20
[ 60.403729] __alloc_pages_nodemask+0x1c3/0x200
[ 60.404941] cache_grow_begin+0x20b/0x2e0
[ 60.406164] fallback_alloc+0x160/0x200
[ 60.407088] kmem_cache_alloc+0x111/0x4e0
[ 60.408038] ? xfs_buf_rele+0x61/0x430
[ 60.408925] kmem_zone_alloc+0x61/0xe0
[ 60.409965] xfs_inode_alloc+0x24/0x1d0
.....


Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_iops.hdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_filestream.hdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_sysctl.cdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_extent_busy.hdiff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
H A Dxfs_stats.hdiff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_fsops.hdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff c8ce540d Fri Jun 16 12:00:05 MDT 2017 Darrick J. Wong <darrick.wong@oracle.com> xfs: remove double-underscore integer types

This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs. This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff c8ce540d Fri Jun 16 12:00:05 MDT 2017 Darrick J. Wong <darrick.wong@oracle.com> xfs: remove double-underscore integer types

This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs. This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff c8ce540d Fri Jun 16 12:00:05 MDT 2017 Darrick J. Wong <darrick.wong@oracle.com> xfs: remove double-underscore integer types

This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs. This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
H A Dxfs_ioctl.hdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff c8ce540d Fri Jun 16 12:00:05 MDT 2017 Darrick J. Wong <darrick.wong@oracle.com> xfs: remove double-underscore integer types

This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs. This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff c8ce540d Fri Jun 16 12:00:05 MDT 2017 Darrick J. Wong <darrick.wong@oracle.com> xfs: remove double-underscore integer types

This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs. This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff c8ce540d Fri Jun 16 12:00:05 MDT 2017 Darrick J. Wong <darrick.wong@oracle.com> xfs: remove double-underscore integer types

This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs. This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
H A Dxfs_message.cdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_extfree_item.hdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_trace.cdiff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 0020a190 Tue Aug 10 19:00:44 MDT 2021 Dave Chinner <dchinner@redhat.com> xfs: AIL needs asynchronous CIL forcing

The AIL pushing is stalling on log forces when it comes across
pinned items. This is happening on removal workloads where the AIL
is dominated by stale items that are removed from AIL when the
checkpoint that marks the items stale is committed to the journal.
This results is relatively few items in the AIL, but those that are
are often pinned as directories items are being removed from are
still being logged.

As a result, many push cycles through the CIL will first issue a
blocking log force to unpin the items. This can take some time to
complete, with tracing regularly showing push delays of half a
second and sometimes up into the range of several seconds. Sequences
like this aren't uncommon:

....
399.829437: xfsaild: last lsn 0x11002dd000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 270ms delay>
400.099622: xfsaild: target 0x11002f3600, prev 0x11002f3600, last lsn 0x0
400.099623: xfsaild: first lsn 0x11002f3600
400.099679: xfsaild: last lsn 0x1100305000 count 16 stuck 11 flushing 0 tout 50
<wanted 50ms, got 500ms delay>
400.589348: xfsaild: target 0x110032e600, prev 0x11002f3600, last lsn 0x0
400.589349: xfsaild: first lsn 0x1100305000
400.589595: xfsaild: last lsn 0x110032e600 count 156 stuck 101 flushing 30 tout 50
<wanted 50ms, got 460ms delay>
400.950341: xfsaild: target 0x1100353000, prev 0x110032e600, last lsn 0x0
400.950343: xfsaild: first lsn 0x1100317c00
400.950436: xfsaild: last lsn 0x110033d200 count 105 stuck 101 flushing 0 tout 20
<wanted 20ms, got 200ms delay>
401.142333: xfsaild: target 0x1100361600, prev 0x1100353000, last lsn 0x0
401.142334: xfsaild: first lsn 0x110032e600
401.142535: xfsaild: last lsn 0x1100353000 count 122 stuck 101 flushing 8 tout 10
<wanted 10ms, got 10ms delay>
401.154323: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x1100353000
401.154328: xfsaild: first lsn 0x1100353000
401.154389: xfsaild: last lsn 0x1100353000 count 101 stuck 101 flushing 0 tout 20
<wanted 20ms, got 300ms delay>
401.451525: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
401.451526: xfsaild: first lsn 0x1100353000
401.451804: xfsaild: last lsn 0x1100377200 count 170 stuck 22 flushing 122 tout 50
<wanted 50ms, got 500ms delay>
401.933581: xfsaild: target 0x1100361600, prev 0x1100361600, last lsn 0x0
....

In each of these cases, every AIL pass saw 101 log items stuck on
the AIL (pinned) with very few other items being found. Each pass, a
log force was issued, and delay between last/first is the sleep time
+ the sync log force time.

Some of these 101 items pinned the tail of the log. The tail of the
log does slowly creep forward (first lsn), but the problem is that
the log is actually out of reservation space because it's been
running so many transactions that stale items that never reach the
AIL but consume log space. Hence we have a largely empty AIL, with
long term pins on items that pin the tail of the log that don't get
pushed frequently enough to keep log space available.

The problem is the hundreds of milliseconds that we block in the log
force pushing the CIL out to disk. The AIL should not be stalled
like this - it needs to run and flush items that are at the tail of
the log with minimal latency. What we really need to do is trigger a
log flush, but then not wait for it at all - we've already done our
waiting for stuff to complete when we backed off prior to the log
force being issued.

Even if we remove the XFS_LOG_SYNC from the xfs_log_force() call, we
still do a blocking flush of the CIL and that is what is causing the
issue. Hence we need a new interface for the CIL to trigger an
immediate background push of the CIL to get it moving faster but not
to wait on that to occur. While the CIL is pushing, the AIL can also
be pushing.

We already have an internal interface to do this -
xlog_cil_push_now() - but we need a wrapper for it to be used
externally. xlog_cil_force_seq() can easily be extended to do what
we need as it already implements the synchronous CIL push via
xlog_cil_push_now(). Add the necessary flags and "push current
sequence" semantics to xlog_cil_force_seq() and convert the AIL
pushing to use it.

One of the complexities here is that the CIL push does not guarantee
that the commit record for the CIL checkpoint is written to disk.
The current log force ensures this by submitting the current ACTIVE
iclog that the commit record was written to. We need the CIL to
actually write this commit record to disk for an async push to
ensure that the checkpoint actually makes it to disk and unpins the
pinned items in the checkpoint on completion. Hence we need to pass
down to the CIL push that we are doing an async flush so that it can
switch out the commit_iclog if necessary to get written to disk when
the commit iclog is finally released.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
H A Dxfs_extent_busy.cdiff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
diff 8ebbf262 Wed Jun 28 12:04:33 MDT 2023 Dave Chinner <dchinner@redhat.com> xfs: don't block in busy flushing when freeing extents

If the current transaction holds a busy extent and we are trying to
allocate a new extent to fix up the free list, we can deadlock if
the AG is entirely empty except for the busy extent held by the
transaction.

This can occur at runtime processing an XEFI with multiple extents
in this path:

__schedule+0x22f at ffffffff81f75e8f
schedule+0x46 at ffffffff81f76366
xfs_extent_busy_flush+0x69 at ffffffff81477d99
xfs_alloc_ag_vextent_size+0x16a at ffffffff8141711a
xfs_alloc_ag_vextent+0x19b at ffffffff81417edb
xfs_alloc_fix_freelist+0x22f at ffffffff8141896f
xfs_free_extent_fix_freelist+0x6a at ffffffff8141939a
__xfs_free_extent+0x99 at ffffffff81419499
xfs_trans_free_extent+0x3e at ffffffff814a6fee
xfs_extent_free_finish_item+0x24 at ffffffff814a70d4
xfs_defer_finish_noroll+0x1f7 at ffffffff81441407
xfs_defer_finish+0x11 at ffffffff814417e1
xfs_itruncate_extents_flags+0x13d at ffffffff8148b7dd
xfs_inactive_truncate+0xb9 at ffffffff8148bb89
xfs_inactive+0x227 at ffffffff8148c4f7
xfs_fs_destroy_inode+0xb8 at ffffffff81496898
destroy_inode+0x3b at ffffffff8127d2ab
do_unlinkat+0x1d1 at ffffffff81270df1
do_syscall_64+0x40 at ffffffff81f6b5f0
entry_SYSCALL_64_after_hwframe+0x44 at ffffffff8200007c

This can also happen in log recovery when processing an EFI
with multiple extents through this path:

context_switch() kernel/sched/core.c:3881
__schedule() kernel/sched/core.c:5111
schedule() kernel/sched/core.c:5186
xfs_extent_busy_flush() fs/xfs/xfs_extent_busy.c:598
xfs_alloc_ag_vextent_size() fs/xfs/libxfs/xfs_alloc.c:1641
xfs_alloc_ag_vextent() fs/xfs/libxfs/xfs_alloc.c:828
xfs_alloc_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:2362
xfs_free_extent_fix_freelist() fs/xfs/libxfs/xfs_alloc.c:3029
__xfs_free_extent() fs/xfs/libxfs/xfs_alloc.c:3067
xfs_trans_free_extent() fs/xfs/xfs_extfree_item.c:370
xfs_efi_recover() fs/xfs/xfs_extfree_item.c:626
xlog_recover_process_efi() fs/xfs/xfs_log_recover.c:4605
xlog_recover_process_intents() fs/xfs/xfs_log_recover.c:4893
xlog_recover_finish() fs/xfs/xfs_log_recover.c:5824
xfs_log_mount_finish() fs/xfs/xfs_log.c:764
xfs_mountfs() fs/xfs/xfs_mount.c:978
xfs_fs_fill_super() fs/xfs/xfs_super.c:1908
mount_bdev() fs/super.c:1417
xfs_fs_mount() fs/xfs/xfs_super.c:1985
legacy_get_tree() fs/fs_context.c:647
vfs_get_tree() fs/super.c:1547
do_new_mount() fs/namespace.c:2843
do_mount() fs/namespace.c:3163
ksys_mount() fs/namespace.c:3372
__do_sys_mount() fs/namespace.c:3386
__se_sys_mount() fs/namespace.c:3383
__x64_sys_mount() fs/namespace.c:3383
do_syscall_64() arch/x86/entry/common.c:296
entry_SYSCALL_64() arch/x86/entry/entry_64.S:180

To avoid this deadlock, we should not block in
xfs_extent_busy_flush() if we hold a busy extent in the current
transaction.

Now that the EFI processing code can handle requeuing a partially
completed EFI, we can detect this situation in
xfs_extent_busy_flush() and return -EAGAIN rather than going to
sleep forever. The -EAGAIN get propagated back out to the
xfs_trans_free_extent() context, where the EFD is populated and the
transaction is rolled, thereby moving the busy extents into the CIL.

At this point, we can retry the extent free operation again with a
clean transaction. If we hit the same "all free extents are busy"
situation when trying to fix up the free list, we can safely call
xfs_extent_busy_flush() and wait for the busy extents to resolve
and wake us. At this point, the allocation search can make progress
again and we can fix up the free list.

This deadlock was first reported by Chandan in mid-2021, but I
couldn't make myself understood during review, and didn't have time
to fix it myself.

It was reported again in March 2023, and again I have found myself
unable to explain the complexities of the solution needed during
review.

As such, I don't have hours more time to waste trying to get the
fix written the way it needs to be written, so I'm just doing it
myself. This patchset is largely based on Wengang Wang's last patch,
but with all the unnecessary stuff removed, split up into multiple
patches and cleaned up somewhat.

Reported-by: Chandan Babu R <chandanrlinux@gmail.com>
Reported-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
H A Dxfs_bmap_util.hdiff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 2c307174 Mon Nov 19 14:31:10 MST 2018 Dave Chinner <dchinner@redhat.com> xfs: flush removing page cache in xfs_reflink_remap_prep

On a sub-page block size filesystem, fsx is failing with a data
corruption after a series of operations involving copying a file
with the destination offset beyond EOF of the destination of the file:

8093(157 mod 256): TRUNCATE DOWN from 0x7a120 to 0x50000 ******WWWW
8094(158 mod 256): INSERT 0x25000 thru 0x25fff (0x1000 bytes)
8095(159 mod 256): COPY 0x18000 thru 0x1afff (0x3000 bytes) to 0x2f400
8096(160 mod 256): WRITE 0x5da00 thru 0x651ff (0x7800 bytes) HOLE
8097(161 mod 256): COPY 0x2000 thru 0x5fff (0x4000 bytes) to 0x6fc00

The second copy here is beyond EOF, and it is to sub-page (4k) but
block aligned (1k) offset. The clone runs the EOF zeroing, landing
in a pre-existing post-eof delalloc extent. This zeroes the post-eof
extents in the page cache just fine, dirtying the pages correctly.

The problem is that xfs_reflink_remap_prep() now truncates the page
cache over the range that it is copying it to, and rounds that down
to cover the entire start page. This removes the dirty page over the
delalloc extent from the page cache without having written it back.
Hence later, when the page cache is flushed, the page at offset
0x6f000 has not been written back and hence exposes stale data,
which fsx trips over less than 10 operations later.

Fix this by changing xfs_reflink_remap_prep() to use
xfs_flush_unmap_range().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
H A Dxfs_export.cdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 35c2a7f4 Sun Oct 07 21:32:51 MDT 2012 Hugh Dickins <hughd@google.com> tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
[<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0
[<ffffffff812d77c3>] do_handle_open+0x163/0x2c0
[<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10
[<ffffffff83a5f3f8>] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Sage Weil <sage@inktank.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
H A Dxfs_stats.cdiff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 18a1e644 Thu Feb 22 01:43:40 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: define an in-memory btree for storing refcount bag info during repairs

Create a new in-memory btree type so that we can store refcount bag info
in a much more memory-efficient and performant format. Recall that the
refcount recordset regenerator computes the new recordset from browsing
the rmap records. Let's say that the rmap records are:

{agbno: 10, length: 40, ...}
{agbno: 11, length: 3, ...}
{agbno: 12, length: 20, ...}
{agbno: 15, length: 1, ...}

It is convenient to have a data structure that could quickly tell us the
refcount for an arbitrary agbno without wasting memory. An array or a
list could do that pretty easily. List suck because of the pointer
overhead. xfarrays are a lot more compact, but we want to minimize
sparse holes in the xfarray to constrain memory usage. Maintaining any
kind of record order isn't needed for correctness, so I created the
"rcbag", which is shorthand for an unordered list of (excerpted) reverse
mappings.

So we add the first rmap to the rcbag, and it looks like:

0: {agbno: 10, length: 40}

The refcount for agbno 10 is 1. Then we move on to block 11, so we add
the second rmap:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}

The refcount for agbno 11 is 2. We move on to block 12, so we add the
third:

0: {agbno: 10, length: 40}
1: {agbno: 11, length: 3}
2: {agbno: 12, length: 20}

The refcount for agbno 12 and 13 is 3. We move on to block 14, and
remove the second rmap:

0: {agbno: 10, length: 40}
1: NULL
2: {agbno: 12, length: 20}

The refcount for agbno 14 is 2. We move on to block 15, and add the
last rmap. But we don't care where it is and we don't want to expand
the array so we put it in slot 1:

0: {agbno: 10, length: 40}
1: {agbno: 15, length: 1}
2: {agbno: 12, length: 20}

The refcount for block 15 is 3. Notice how order doesn't matter in this
list? That's why repair uses an unordered list, or "bag". The data
structure is not a set because it does not guarantee uniqueness.

That said, adding and removing specific items is now an O(n) operation
because we have no idea where that item might be in the list. Overall,
the runtime is O(n^2) which is bad.

I realized that I could easily refactor the btree code and reimplement
the refcount bag with an xfbtree. Adding and removing is now O(log2 n),
so the runtime is at least O(n log2 n), which is much faster. In the
end, the rcbag becomes a sorted list, but that's merely a detail of the
implementation. The repair code doesn't care.

(Note: That horrible xfs_db bmap_inflate command can be used to exercise
this sort of rcbag insanity by cranking up refcounts quickly.)

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
/linux-master/fs/xfs/scrub/
H A Dalloc.cdiff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 0b61f8a4 Tue Jun 05 20:42:14 MDT 2018 Dave Chinner <dchinner@redhat.com> xfs: convert to SPDX license tags

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}

/^ \* This program is free software/ {
hdr = 2.0;
next
}

/any later version./ {
tag = "GPL-2.0+"
next
}

/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}

/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}

/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}

// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}

END { }
$

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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