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d4c75a1b |
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15-Jan-2024 |
Dave Chinner <dchinner@redhat.com> |
xfs: convert remaining kmem_free() to kfree() The remaining callers of kmem_free() are freeing heap memory, so we can convert them directly to kfree() and get rid of kmem_free() altogether. This conversion was done with: $ for f in `git grep -l kmem_free fs/xfs`; do > sed -i s/kmem_free/kfree/ $f > done $ Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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#
10634530 |
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15-Jan-2024 |
Dave Chinner <dchinner@redhat.com> |
xfs: convert kmem_zalloc() to kzalloc() There's no reason to keep the kmem_zalloc() around anymore, it's just a thin wrapper around kmalloc(), so lets get rid of it. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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#
939bd50d |
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28-Jun-2023 |
Dave Chinner <dchinner@redhat.com> |
xfs: don't reverse order of items in bulk AIL insertion XFS has strict metadata ordering requirements. One of the things it does is maintain the commit order of items from transaction commit through the CIL and into the AIL. That is, if a transaction logs item A before item B in a modification, then they will be inserted into the CIL in the order {A, B}. These items are then written into the iclog during checkpointing in the order {A, B}. When the checkpoint commits, they are supposed to be inserted into the AIL in the order {A, B}, and when they are pushed from the AIL, they are pushed in the order {A, B}. If we crash, log recovery then replays the two items from the checkpoint in the order {A, B}, resulting in the objects the items apply to being queued for writeback at the end of the checkpoint in the order {A, B}. This means recovery behaves the same way as the runtime code. In places, we have subtle dependencies on this ordering being maintained. One of this place is performing intent recovery from the log. It assumes that recovering an intent will result in a non-intent object being the first thing that is modified in the recovery transaction, and so when the transaction commits and the journal flushes, the first object inserted into the AIL beyond the intent recovery range will be a non-intent item. It uses the transistion from intent items to non-intent items to stop the recovery pass. A recent log recovery issue indicated that an intent was appearing as the first item in the AIL beyond the recovery range, hence breaking the end of recovery detection that exists. Tracing indicated insertion of the items into the AIL was apparently occurring in the right order (the intent was last in the commit item list), but the intent was appearing first in the AIL. IOWs, the order of items in the AIL was {D,C,B,A}, not {A,B,C,D}, and bulk insertion was reversing the order of the items in the batch of items being inserted. Lucky for us, all the items fed to bulk insertion have the same LSN, so the reversal of order does not affect the log head/tail tracking that is based on the contents of the AIL. It only impacts on code that has implicit, subtle dependencies on object order, and AFAICT only the intent recovery loop is impacted by it. Make sure bulk AIL insertion does not reorder items incorrectly. Fixes: 0e57f6a36f9b ("xfs: bulk AIL insertion during transaction commit") Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
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#
e5827a00 |
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28-Nov-2022 |
Darrick J. Wong <djwong@kernel.org> |
xfs: shut up -Wuninitialized in xfsaild_push -Wuninitialized complains about @target in xfsaild_push being uninitialized in the case where the waitqueue is active but there is no last item in the AIL to wait for. I /think/ it should never be the case that the subsequent xfs_trans_ail_cursor_first returns a log item and hence we'll never end up at XFS_LSN_CMP, but let's make this explicit. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
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#
fc93812c |
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18-Oct-2022 |
Colin Ian King <colin.i.king@gmail.com> |
xfs: remove redundant pointer lip The assignment to pointer lip is not really required, the pointer lip is redundant and can be removed. Cleans up clang-scan warning: warning: Although the value stored to 'lip' is used in the enclosing expression, the value is never actually read from 'lip' [deadcode.DeadStores] Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
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#
f5d39b02 |
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22-Aug-2022 |
Peter Zijlstra <peterz@infradead.org> |
freezer,sched: Rewrite core freezer logic Rewrite the core freezer to behave better wrt thawing and be simpler in general. By replacing PF_FROZEN with TASK_FROZEN, a special block state, it is ensured frozen tasks stay frozen until thawed and don't randomly wake up early, as is currently possible. As such, it does away with PF_FROZEN and PF_FREEZER_SKIP, freeing up two PF_flags (yay!). Specifically; the current scheme works a little like: freezer_do_not_count(); schedule(); freezer_count(); And either the task is blocked, or it lands in try_to_freezer() through freezer_count(). Now, when it is blocked, the freezer considers it frozen and continues. However, on thawing, once pm_freezing is cleared, freezer_count() stops working, and any random/spurious wakeup will let a task run before its time. That is, thawing tries to thaw things in explicit order; kernel threads and workqueues before doing bringing SMP back before userspace etc.. However due to the above mentioned races it is entirely possible for userspace tasks to thaw (by accident) before SMP is back. This can be a fatal problem in asymmetric ISA architectures (eg ARMv9) where the userspace task requires a special CPU to run. As said; replace this with a special task state TASK_FROZEN and add the following state transitions: TASK_FREEZABLE -> TASK_FROZEN __TASK_STOPPED -> TASK_FROZEN __TASK_TRACED -> TASK_FROZEN The new TASK_FREEZABLE can be set on any state part of TASK_NORMAL (IOW. TASK_INTERRUPTIBLE and TASK_UNINTERRUPTIBLE) -- any such state is already required to deal with spurious wakeups and the freezer causes one such when thawing the task (since the original state is lost). The special __TASK_{STOPPED,TRACED} states *can* be restored since their canonical state is in ->jobctl. With this, frozen tasks need an explicit TASK_FROZEN wakeup and are free of undue (early / spurious) wakeups. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/20220822114649.055452969@infradead.org
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#
b5f17bec |
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29-Mar-2022 |
Dave Chinner <dchinner@redhat.com> |
xfs: log shutdown triggers should only shut down the log We've got a mess on our hands. 1. xfs_trans_commit() cannot cancel transactions because the mount is shut down - that causes dirty, aborted, unlogged log items to sit unpinned in memory and potentially get written to disk before the log is shut down. Hence xfs_trans_commit() can only abort transactions when xlog_is_shutdown() is true. 2. xfs_force_shutdown() is used in places to cause the current modification to be aborted via xfs_trans_commit() because it may be impractical or impossible to cancel the transaction directly, and hence xfs_trans_commit() must cancel transactions when xfs_is_shutdown() is true in this situation. But we can't do that because of #1. 3. Log IO errors cause log shutdowns by calling xfs_force_shutdown() to shut down the mount and then the log from log IO completion. 4. xfs_force_shutdown() can result in a log force being issued, which has to wait for log IO completion before it will mark the log as shut down. If #3 races with some other shutdown trigger that runs a log force, we rely on xfs_force_shutdown() silently ignoring #3 and avoiding shutting down the log until the failed log force completes. 5. To ensure #2 always works, we have to ensure that xfs_force_shutdown() does not return until the the log is shut down. But in the case of #4, this will result in a deadlock because the log Io completion will block waiting for a log force to complete which is blocked waiting for log IO to complete.... So the very first thing we have to do here to untangle this mess is dissociate log shutdown triggers from mount shutdowns. We already have xlog_forced_shutdown, which will atomically transistion to the log a shutdown state. Due to internal asserts it cannot be called multiple times, but was done simply because the only place that could call it was xfs_do_force_shutdown() (i.e. the mount shutdown!) and that could only call it once and once only. So the first thing we do is remove the asserts. We then convert all the internal log shutdown triggers to call xlog_force_shutdown() directly instead of xfs_force_shutdown(). This allows the log shutdown triggers to shut down the log without needing to care about mount based shutdown constraints. This means we shut down the log independently of the mount and the mount may not notice this until it's next attempt to read or modify metadata. At that point (e.g. xfs_trans_commit()) it will see that the log is shutdown, error out and shutdown the mount. To ensure that all the unmount behaviours and asserts track correctly as a result of a log shutdown, propagate the shutdown up to the mount if it is not already set. This keeps the mount and log state in sync, and saves a huge amount of hassle where code fails because of a log shutdown but only checks for mount shutdowns and hence ends up doing the wrong thing. Cleaning up that mess is an exercise for another day. This enables us to address the other problems noted above in followup patches. 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>
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#
8eda8721 |
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17-Mar-2022 |
Dave Chinner <dchinner@redhat.com> |
xfs: AIL should be log centric The AIL operates purely on log items, so it is a log centric subsystem. Divorce it from the xfs_mount and instead have it pass around xlog pointers. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
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#
941fbdfd |
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17-Mar-2022 |
Dave Chinner <dchinner@redhat.com> |
xfs: xfs_ail_push_all_sync() stalls when racing with updates xfs_ail_push_all_sync() has a loop like this: while max_ail_lsn { prepare_to_wait(ail_empty) target = max_ail_lsn wake_up(ail_task); schedule() } Which is designed to sleep until the AIL is emptied. When xfs_ail_update_finish() moves the tail of the log, it does: if (list_empty(&ailp->ail_head)) wake_up_all(&ailp->ail_empty); So it will only wake up the sync push waiter when the AIL goes empty. If, by the time the push waiter has woken, the AIL has more in it, it will reset the target, wake the push task and go back to sleep. The problem here is that if the AIL is having items added to it when xfs_ail_push_all_sync() is called, then they may get inserted into the AIL at a LSN higher than the target LSN. At this point, xfsaild_push() will see that the target is X, the item LSNs are (X+N) and skip over them, hence never pushing the out. The result of this the AIL will not get emptied by the AIL push thread, hence xfs_ail_finish_update() will never see the AIL being empty even if it moves the tail. Hence xfs_ail_push_all_sync() never gets woken and hence cannot update the push target to capture the items beyond the current target on the LSN. This is a TOCTOU type of issue so the way to avoid it is to not use the push target at all for sync pushes. We know that a sync push is being requested by the fact the ail_empty wait queue is active, hence the xfsaild can just set the target to max_ail_lsn on every push that we see the wait queue active. Hence we no longer will leave items on the AIL that are beyond the LSN sampled at the start of a sync push. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
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#
75c8c50f |
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18-Aug-2021 |
Dave Chinner <dchinner@redhat.com> |
xfs: replace XFS_FORCED_SHUTDOWN with xfs_is_shutdown Remove the shouty macro and instead use the inline function that matches other state/feature check wrapper naming. This conversion was done with sed. 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>
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#
0020a190 |
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10-Aug-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>
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#
b63da6c8 |
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05-Aug-2020 |
Randy Dunlap <rdunlap@infradead.org> |
xfs: delete duplicated words + other fixes Delete repeated words in fs/xfs/. {we, that, the, a, to, fork} Change "it it" to "it is" in one location. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> To: linux-fsdevel@vger.kernel.org Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: linux-xfs@vger.kernel.org Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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#
f376b45e |
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16-Jul-2020 |
Brian Foster <bfoster@redhat.com> |
xfs: drain the buf delwri queue before xfsaild idles xfsaild is racy with respect to transaction abort and shutdown in that the task can idle or exit with an empty AIL but buffers still on the delwri queue. This was partly addressed by cancelling the delwri queue before the task exits to prevent memory leaks, but it's also possible for xfsaild to empty and idle with buffers on the delwri queue. For example, a transaction that pins a buffer that also happens to sit on the AIL delwri queue will explicitly remove the associated log item from the AIL if the transaction aborts. The side effect of this is an unmount hang in xfs_wait_buftarg() as the associated buffers remain held by the delwri queue indefinitely. This is reproduced on repeated runs of generic/531 with an fs format (-mrmapbt=1 -bsize=1k) that happens to also reproduce transaction aborts. Update xfsaild to not idle until both the AIL and associated delwri queue are empty and update the push code to continue delwri queue submission attempts even when the AIL is empty. This allows the AIL to eventually release aborted buffers stranded on the delwri queue when they are unlocked by the associated transaction. This should have no significant effect on normal runtime behavior because the xfsaild currently idles only when the AIL is empty and in practice the AIL is rarely empty with a populated delwri queue. The items must be AIL resident to land in the queue in the first place and generally aren't removed until writeback completes. Note that the pre-existing delwri queue cancel logic in the exit path is retained because task stop is external, could technically come at any point, and xfsaild is still responsible to release its buffer references before it exits. 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>
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#
298f7bec |
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29-Jun-2020 |
Dave Chinner <dchinner@redhat.com> |
xfs: pin inode backing buffer to the inode log item When we dirty an inode, we are going to have to write it disk at some point in the near future. This requires the inode cluster backing buffer to be present in memory. Unfortunately, under severe memory pressure we can reclaim the inode backing buffer while the inode is dirty in memory, resulting in stalling the AIL pushing because it has to do a read-modify-write cycle on the cluster buffer. When we have no memory available, the read of the cluster buffer blocks the AIL pushing process, and this causes all sorts of issues for memory reclaim as it requires inode writeback to make forwards progress. Allocating a cluster buffer causes more memory pressure, and results in more cluster buffers to be reclaimed, resulting in more RMW cycles to be done in the AIL context and everything then backs up on AIL progress. Only the synchronous inode cluster writeback in the the inode reclaim code provides some level of forwards progress guarantees that prevent OOM-killer rampages in this situation. Fix this by pinning the inode backing buffer to the inode log item when the inode is first dirtied (i.e. in xfs_trans_log_inode()). This may mean the first modification of an inode that has been held in cache for a long time may block on a cluster buffer read, but we can do that in transaction context and block safely until the buffer has been allocated and read. Once we have the cluster buffer, the inode log item takes a reference to it, pinning it in memory, and attaches it to the log item for future reference. This means we can always grab the cluster buffer from the inode log item when we need it. When the inode is finally cleaned and removed from the AIL, we can drop the reference the inode log item holds on the cluster buffer. Once all inodes on the cluster buffer are clean, the cluster buffer will be unpinned and it will be available for memory reclaim to reclaim again. This avoids the issues with needing to do RMW cycles in the AIL pushing context, and hence allows complete non-blocking inode flushing to be performed by the AIL pushing context. 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>
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#
e98084b8 |
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29-Jun-2020 |
Dave Chinner <dchinner@redhat.com> |
xfs: move xfs_clear_li_failed out of xfs_ail_delete_one() xfs_ail_delete_one() is called directly from dquot and inode IO completion, as well as from the generic xfs_trans_ail_delete() function. Inodes are about to have their own failure handling, and dquots will in future, too. Pull the clearing of the LI_FAILED flag up into the callers so we can customise the code appropriately. 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>
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#
86a37174 |
|
01-May-2020 |
Darrick J. Wong <darrick.wong@oracle.com> |
xfs: refactor adding recovered intent items to the log During recovery, every intent that we recover from the log has to be added to the AIL. Replace the open-coded addition with a helper. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
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#
2b3cf093 |
|
06-May-2020 |
Brian Foster <bfoster@redhat.com> |
xfs: combine xfs_trans_ail_[remove|delete]() Now that the functions and callers of xfs_trans_ail_[remove|delete]() have been fixed up appropriately, the only difference between the two is the shutdown behavior. There are only a few callers of the _remove() variant, so make the shutdown conditional on the parameter and combine the two functions. Suggested-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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#
849274c1 |
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06-May-2020 |
Brian Foster <bfoster@redhat.com> |
xfs: acquire ->ail_lock from xfs_trans_ail_delete() Several callers acquire the lock just prior to the call. Callers that require ->ail_lock for other purposes already check IN_AIL state and thus don't require the additional shutdown check in the helper. Push the lock down into xfs_trans_ail_delete(), open code the instances that still acquire it, and remove the unnecessary ailp parameter. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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#
cb6ad099 |
|
06-May-2020 |
Brian Foster <bfoster@redhat.com> |
xfs: refactor failed buffer resubmission into xfsaild Flush locked log items whose underlying buffers fail metadata writeback are tagged with a special flag to indicate that the flush lock is already held. This is currently implemented in the type specific ->iop_push() callback, but the processing required for such items is not type specific because we're only doing basic state management on the underlying buffer. Factor the failed log item handling out of the inode and dquot ->iop_push() callbacks and open code the buffer resubmit helper into a single helper called from xfsaild_push_item(). This provides a generic mechanism for handling failed metadata buffer writeback with a bit less code. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-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>
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#
8eb807bd |
|
24-Mar-2020 |
Dave Chinner <dchinner@redhat.com> |
xfs: tail updates only need to occur when LSN changes We currently wake anything waiting on the log tail to move whenever the log item at the tail of the log is removed. Historically this was fine behaviour because there were very few items at any given LSN. But with delayed logging, there may be thousands of items at any given LSN, and we can't move the tail until they are all gone. Hence if we are removing them in near tail-first order, we might be waking up processes waiting on the tail LSN to change (e.g. log space waiters) repeatedly without them being able to make progress. This also occurs with the new sync push waiters, and can result in thousands of spurious wakeups every second when under heavy direct reclaim pressure. To fix this, check that the tail LSN has actually changed on the AIL before triggering wakeups. This will reduce the number of spurious wakeups when doing bulk AIL removal and make this code much more efficient. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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4165994a |
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24-Mar-2020 |
Dave Chinner <dchinner@redhat.com> |
xfs: factor common AIL item deletion code Factor the common AIL deletion code that does all the wakeups into a helper so we only have one copy of this somewhat tricky code to interface with all the wakeups necessary when the LSN of the log tail changes. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Allison Collins <allison.henderson@oracle.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>
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#
10a98cb1 |
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10-Mar-2020 |
Eric Biggers <ebiggers@google.com> |
xfs: clear PF_MEMALLOC before exiting xfsaild thread Leaving PF_MEMALLOC set when exiting a kthread causes it to remain set during do_exit(). That can confuse things. In particular, if BSD process accounting is enabled, then do_exit() writes data to an accounting file. If that file has FS_SYNC_FL set, then this write occurs synchronously and can misbehave if PF_MEMALLOC is set. For example, if the accounting file is located on an XFS filesystem, then a WARN_ON_ONCE() in iomap_do_writepage() is triggered and the data doesn't get written when it should. Or if the accounting file is located on an ext4 filesystem without a journal, then a WARN_ON_ONCE() in ext4_write_inode() is triggered and the inode doesn't get written. Fix this in xfsaild() by using the helper functions to save and restore PF_MEMALLOC. This can be reproduced as follows in the kvm-xfstests test appliance modified to add the 'acct' Debian package, and with kvm-xfstests's recommended kconfig modified to add CONFIG_BSD_PROCESS_ACCT=y: mkfs.xfs -f /dev/vdb mount /vdb touch /vdb/file chattr +S /vdb/file accton /vdb/file mkfs.xfs -f /dev/vdc mount /vdc umount /vdc It causes: WARNING: CPU: 1 PID: 336 at fs/iomap/buffered-io.c:1534 CPU: 1 PID: 336 Comm: xfsaild/vdc Not tainted 5.6.0-rc5 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014 RIP: 0010:iomap_do_writepage+0x16b/0x1f0 fs/iomap/buffered-io.c:1534 [...] Call Trace: write_cache_pages+0x189/0x4d0 mm/page-writeback.c:2238 iomap_writepages+0x1c/0x33 fs/iomap/buffered-io.c:1642 xfs_vm_writepages+0x65/0x90 fs/xfs/xfs_aops.c:578 do_writepages+0x41/0xe0 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0xd2/0x120 mm/filemap.c:421 file_write_and_wait_range+0x71/0xc0 mm/filemap.c:760 xfs_file_fsync+0x7a/0x2b0 fs/xfs/xfs_file.c:114 generic_write_sync include/linux/fs.h:2867 [inline] xfs_file_buffered_aio_write+0x379/0x3b0 fs/xfs/xfs_file.c:691 call_write_iter include/linux/fs.h:1901 [inline] new_sync_write+0x130/0x1d0 fs/read_write.c:483 __kernel_write+0x54/0xe0 fs/read_write.c:515 do_acct_process+0x122/0x170 kernel/acct.c:522 slow_acct_process kernel/acct.c:581 [inline] acct_process+0x1d4/0x27c kernel/acct.c:607 do_exit+0x83d/0xbc0 kernel/exit.c:791 kthread+0xf1/0x140 kernel/kthread.c:257 ret_from_fork+0x27/0x50 arch/x86/entry/entry_64.S:352 This bug was originally reported by syzbot at https://lore.kernel.org/r/0000000000000e7156059f751d7b@google.com. Reported-by: syzbot+1f9dc49e8de2582d90c2@syzkaller.appspotmail.com Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
daebba1b |
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26-Feb-2020 |
Jules Irenge <jbi.octave@gmail.com> |
xfs: Add missing annotation to xfs_ail_check() Sparse reports a warning at xfs_ail_check() warning: context imbalance in xfs_ail_check() - unexpected unlock The root cause is the missing annotation at xfs_ail_check() Add the missing __must_hold(&ailp->ail_lock) annotation Signed-off-by: Jules Irenge <jbi.octave@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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#
cf085a1b |
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07-Nov-2019 |
Joe Perches <joe@perches.com> |
xfs: Correct comment tyops -> typos Just fix the typos checkpatch notices... Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Bill O'Donnell <billodo@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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#
e1d3d218 |
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04-Nov-2019 |
Ian Kent <raven@themaw.net> |
xfs: use super s_id instead of struct xfs_mount m_fsname Eliminate struct xfs_mount field m_fsname by using the super block s_id field directly. Signed-off-by: Ian Kent <raven@themaw.net> 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>
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#
efe2330f |
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28-Jun-2019 |
Christoph Hellwig <hch@lst.de> |
xfs: remove the xfs_log_item_t typedef Signed-off-by: Christoph Hellwig <hch@lst.de> 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>
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e8b78db7 |
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28-Jun-2019 |
Christoph Hellwig <hch@lst.de> |
xfs: don't require log items to implement optional methods Just check if they are present first. Signed-off-by: Christoph Hellwig <hch@lst.de> 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>
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#
5467b34b |
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28-Jun-2019 |
Darrick J. Wong <darrick.wong@oracle.com> |
xfs: move xfs_ino_geometry to xfs_shared.h The inode geometry structure isn't related to ondisk format; it's support for the mount structure. Move it to xfs_shared.h. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
efc3289c |
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18-Oct-2018 |
Brian Foster <bfoster@redhat.com> |
xfs: clear ail delwri queued bufs on unmount of shutdown fs In the typical unmount case, the AIL is forced out by the unmount sequence before the xfsaild task is stopped. Since AIL items are removed on writeback completion, this means that the AIL ->ail_buf_list delwri queue has been drained. This is not always true in the shutdown case, however. It's possible for buffers to sit on a delwri queue for a period of time across submission attempts if said items are locked or have been relogged and pinned since first added to the queue. If the attempt to log such an item results in a log I/O error, the error processing can shutdown the fs, remove the item from the AIL, stale the buffer (dropping the LRU reference) and clear its delwri queue state. The latter bit means the buffer will be released from a delwri queue on the next submission attempt, but this might never occur if the filesystem has shutdown and the AIL is empty. This means that such buffers are held indefinitely by the AIL delwri queue across destruction of the AIL. Aside from being a memory leak, these buffers can also hold references to in-core perag structures. The latter problem manifests as a generic/475 failure, reproducing the following asserts at unmount time: XFS: Assertion failed: atomic_read(&pag->pag_ref) == 0, file: fs/xfs/xfs_mount.c, line: 151 XFS: Assertion failed: atomic_read(&pag->pag_ref) == 0, file: fs/xfs/xfs_mount.c, line: 132 To prevent this problem, clear the AIL delwri queue as a final step before xfsaild() exit. The !empty state should never occur in the normal case, so add an assert to catch unexpected problems going forward. [dgc: add comment explaining need for xfs_buf_delwri_cancel() after calling xfs_buf_delwri_submit_nowait().] Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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#
0b61f8a4 |
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05-Jun-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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d686d12d |
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09-May-2018 |
Dave Chinner <dchinner@redhat.com> |
xfs: don't assert fail with AIL lock held Been hitting AIL ordering assert failures recently, but been unable to trace them down because the system immediately hangs up onteh spinlock that was held when this assert fires: XFS: Assertion failed: XFS_LSN_CMP(prev_lip->li_lsn, lip->li_lsn) <= 0, file: fs/xfs/xfs_trans_ail.c, line: 52 Move the assertions outside of the spinlock so the corpse can be dissected. Thanks to Brian Foster for supplying a clean way of doing this. Signed-Off-By: Dave Chinner <dchinner@redhat.com> Reviewed-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>
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22525c17 |
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09-May-2018 |
Dave Chinner <dchinner@redhat.com> |
xfs: log item flags are racy The log item flags contain a field that is protected by the AIL lock - the XFS_LI_IN_AIL flag. We use non-atomic RMW operations to set and clear these flags, but most of the updates and checks are not done with the AIL lock held and so are susceptible to update races. Fix this by changing the log item flags to use atomic bitops rather than be reliant on the AIL lock for update serialisation. Signed-Off-By: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> 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>
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57e80956 |
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07-Mar-2018 |
Matthew Wilcox <willy@infradead.org> |
xfs: Rename xa_ elements to ail_ This is a simple rename, except that xa_ail becomes ail_head. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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#
e9e899a2 |
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31-Oct-2017 |
Darrick J. Wong <darrick.wong@oracle.com> |
xfs: move error injection tags into their own file Move the error injection tag names into a libxfs header so that we can share it between kernel and userspace. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
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#
0bd89676 |
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17-Oct-2017 |
Hou Tao <houtao1@huawei.com> |
xfs: check kthread_should_stop() after the setting of task state A umount hang is possible when a race occurs between the umount process and the xfsaild kthread. The following sequences outline the race: xfsaild: kthread_should_stop() => return false, so xfsaild continue umount: set_bit(KTHREAD_SHOULD_STOP, &kthread->flags) => by kthread_stop() umount: wake_up_process() => because xfsaild is still running, so 0 is returned xfsaild: __set_current_state(TASK_INTERRUPTIBLE) xfsaild: schedule() => now, xfsaild will wait indefinitely umount: wait_for_completion() => and umount will hang To fix that, we need to check kthread_should_stop() after we set the task state, so the xfsaild will either see the stop bit and exit or the task state is reset to runnable by wake_up_process() such that it isn't scheduled out indefinitely and detects the stop bit at the next iteration. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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#
7f4d01f3 |
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08-Aug-2017 |
Brian Foster <bfoster@redhat.com> |
xfs: add log item pinning error injection tag Add an error injection tag to force log items in the AIL to the pinned state. This option can be used by test infrastructure to induce head behind tail conditions. Specifically, this is intended to be used by xfstests to reproduce log recovery problems after failed/corrupted log writes overwrite the last good tail LSN in the log. When enabled, AIL push attempts see log items in the AIL in the pinned state. This stalls metadata writeback and thus prevents the current tail of the log from moving forward. When disabled, subsequent AIL pushes observe the log items in their appropriate state and filesystem operation continues as normal. Signed-off-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>
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d3a304b6 |
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08-Aug-2017 |
Carlos Maiolino <cmaiolino@redhat.com> |
xfs: Properly retry failed inode items in case of error during buffer writeback When a buffer has been failed during writeback, the inode items into it are kept flush locked, and are never resubmitted due the flush lock, so, if any buffer fails to be written, the items in AIL are never written to disk and never unlocked. This causes unmount operation to hang due these items flush locked in AIL, but this also causes the items in AIL to never be written back, even when the IO device comes back to normal. I've been testing this patch with a DM-thin device, creating a filesystem larger than the real device. When writing enough data to fill the DM-thin device, XFS receives ENOSPC errors from the device, and keep spinning on xfsaild (when 'retry forever' configuration is set). At this point, the filesystem can not be unmounted because of the flush locked items in AIL, but worse, the items in AIL are never retried at all (once xfs_inode_item_push() will skip the items that are flush locked), even if the underlying DM-thin device is expanded to the proper size. This patch fixes both cases, retrying any item that has been failed previously, using the infra-structure provided by the previous patch. Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Carlos Maiolino <cmaiolino@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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27af1bbf |
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21-Apr-2017 |
Christoph Hellwig <hch@lst.de> |
xfs: remove xfs_trans_ail_delete_bulk xfs_iflush_done uses an on-stack variable length array to pass the log items to be deleted to xfs_trans_ail_delete_bulk. On-stack VLAs are a nasty gcc extension that can lead to unbounded stack allocations, but fortunately we can easily avoid them by simply open coding xfs_trans_ail_delete_bulk in xfs_iflush_done, which is the only caller of it except for the single-item xfs_trans_ail_delete. Signed-off-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>
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#
18f1df4e |
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07-Feb-2016 |
Michal Hocko <mhocko@suse.com> |
xfs: Make xfsaild freezeable again Hendik has reported suspend failures due to xfsaild blocking the freezer to settle down. Jan 17 19:59:56 linux-6380 kernel: PM: Syncing filesystems ... done. Jan 17 19:59:56 linux-6380 kernel: PM: Preparing system for sleep (mem) Jan 17 19:59:56 linux-6380 kernel: Freezing user space processes ... (elapsed 0.001 seconds) done. Jan 17 19:59:56 linux-6380 kernel: Freezing remaining freezable tasks ... Jan 17 19:59:56 linux-6380 kernel: Freezing of tasks failed after 20.002 seconds (1 tasks refusing to freeze, wq_busy=0): Jan 17 19:59:56 linux-6380 kernel: xfsaild/dm-5 S 00000000 0 1293 2 0x00000080 Jan 17 19:59:56 linux-6380 kernel: f0ef5f00 00000046 00000200 00000000 ffff9022 c02d3800 00000000 00000032 Jan 17 19:59:56 linux-6380 kernel: ee0b2400 00000032 f71e0d00 f36fabc0 f0ef2d00 f0ef6000 f0ef2d00 f12f90c0 Jan 17 19:59:56 linux-6380 kernel: f0ef5f0c c0844e44 00000000 f0ef5f6c f811e0be 00000000 00000000 f0ef2d00 Jan 17 19:59:56 linux-6380 kernel: Call Trace: Jan 17 19:59:56 linux-6380 kernel: [<c0844e44>] schedule+0x34/0x90 Jan 17 19:59:56 linux-6380 kernel: [<f811e0be>] xfsaild+0x5de/0x600 [xfs] Jan 17 19:59:56 linux-6380 kernel: [<c0286cbb>] kthread+0x9b/0xb0 Jan 17 19:59:56 linux-6380 kernel: [<c0848a79>] ret_from_kernel_thread+0x21/0x38 The issue has been there for quite some time but it has been made visible by only by 24ba16bb3d49 ("xfs: clear PF_NOFREEZE for xfsaild kthread") because the suspend started seeing xfsaild. The above commit has missed that the !xfs_ail_min branch might call schedule with TASK_INTERRUPTIBLE without calling try_to_freeze so the pm suspend would wake up the kernel thread over and over again without any progress. What we want here is to use freezable_schedule instead to hide the thread from the suspend. While we are here also change schedule_timeout to freezable variant to prevent from spurious wakeups by suspend. [dchinner: re-add set_freezeable call so the freezer will account properly for this kthread. ] Reported-by: Hendrik Woltersdorf <hendrikw@arcor.de> Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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3e85286e |
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18-Jan-2016 |
Dave Chinner <david@fromorbit.com> |
Revert "xfs: clear PF_NOFREEZE for xfsaild kthread" This reverts commit 24ba16bb3d499c49974669cd8429c3e4138ab102 as it prevents machines from suspending. This regression occurs when the xfsaild is idle on entry to suspend, and so there s no activity to wake it from it's idle sleep and hence see that it is supposed to freeze. Hence the freezer times out waiting for it and suspend is cancelled. There is no obvious fix for this short of freezing the filesystem properly, so revert this change for now. cc: <stable@vger.kernel.org> # 4.4 Signed-off-by: Dave Chinner <david@fromorbit.com> Acked-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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24ba16bb |
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01-Nov-2015 |
Jiri Kosina <jkosina@suse.cz> |
xfs: clear PF_NOFREEZE for xfsaild kthread Since xfsaild has been converted to kthread in 0030807c, it calls try_to_freeze() during every AIL push iteration. It however doesn't set itself as freezable, and therefore this try_to_freeze() will never do anything. Before (hopefully eventually) kthread freezing gets converted to fileystem freezing, we'd rather mark xfsaild freezable (as it can generate I/O during suspend). Signed-off-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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#
ff6d6af2 |
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12-Oct-2015 |
Bill O'Donnell <billodo@redhat.com> |
xfs: per-filesystem stats counter implementation This patch modifies the stats counting macros and the callers to those macros to properly increment, decrement, and add-to the xfs stats counts. The counts for global and per-fs stats are correctly advanced, and cleared by writing a "1" to the corresponding clear file. global counts: /sys/fs/xfs/stats/stats per-fs counts: /sys/fs/xfs/sda*/stats/stats global clear: /sys/fs/xfs/stats/stats_clear per-fs clear: /sys/fs/xfs/sda*/stats/stats_clear [dchinner: cleaned up macro variables, removed CONFIG_FS_PROC around stats structures and macros. ] Signed-off-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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db9d67d6 |
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21-Jun-2015 |
Christoph Hellwig <hch@lst.de> |
xfs: remove __psint_t and __psunsigned_t Replace uses of __psint_t with the proper uintptr_t and ptrdiff_t types, and remove the defintions of __psint_t and __psunsigned_t. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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bb58e618 |
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27-Nov-2014 |
Christoph Hellwig <hch@lst.de> |
xfs: move most of xfs_sb.h to xfs_format.h More on-disk format consolidation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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4fb6e8ad |
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27-Nov-2014 |
Christoph Hellwig <hch@lst.de> |
xfs: merge xfs_ag.h into xfs_format.h More on-disk format consolidation. A few declarations that weren't on-disk format related move into better suitable spots. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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#
2451337d |
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24-Jun-2014 |
Dave Chinner <dchinner@redhat.com> |
xfs: global error sign conversion Convert all the errors the core XFs code to negative error signs like the rest of the kernel and remove all the sign conversion we do in the interface layers. Errors for conversion (and comparison) found via searches like: $ git grep " E" fs/xfs $ git grep "return E" fs/xfs $ git grep " E[A-Z].*;$" fs/xfs Negation points found via searches like: $ git grep "= -[a-z,A-Z]" fs/xfs $ git grep "return -[a-z,A-D,F-Z]" fs/xfs $ git grep " -[a-z].*;" fs/xfs [ with some bits I missed from Brian Foster ] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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#
e4a1e29c |
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14-Apr-2014 |
Eric Sandeen <sandeen@redhat.com> |
xfs: remove unused ail pointer arg from xfs_trans_ail_cursor_done() Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
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#
750b9c90 |
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31-Oct-2013 |
Dave Chinner <dchinner@redhat.com> |
xfs: trace AIL manipulations I debugging a log tail issue on a RHEL6 kernel, I added these trace points to trace log items being added, moved and removed in the AIL and how that affected the log tail LSN that was written to the log. They were very helpful in that they immediately identified the cause of the problem being seen. Hence I'd like to always have them available for use. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
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#
239880ef |
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22-Oct-2013 |
Dave Chinner <dchinner@redhat.com> |
xfs: decouple log and transaction headers xfs_trans.h has a dependency on xfs_log.h for a couple of structures. Most code that does transactions doesn't need to know anything about the log, but this dependency means that they have to include xfs_log.h. Decouple the xfs_trans.h and xfs_log.h header files and clean up the includes to be in dependency order. In doing this, remove the direct include of xfs_trans_reserve.h from xfs_trans.h so that we remove the dependency between xfs_trans.h and xfs_mount.h. Hence the xfs_trans.h include can be moved to the indicate the actual dependencies other header files have on it. Note that these are kernel only header files, so this does not translate to any userspace changes at all. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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904c17e6 |
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28-Aug-2013 |
Dave Chinner <dchinner@redhat.com> |
xfs: finish removing IOP_* macros. In optimising the CIL operations, some of the IOP_* macros for calling log item operations were removed. Remove the rest of them as Christoph requested. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Geoffrey Wehrman <gwehrman@sgi.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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8d1d4083 |
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14-Aug-2013 |
Jie Liu <jeff.liu@oracle.com> |
xfs: Simplify xfs_ail_min() with list_first_entry_or_null() At xfs_ail_min(), we do check if the AIL list is empty or not before returning the first item in it with list_empty() and list_first_entry(). This can be simplified a bit with a new list operation routine that is the list_first_entry_or_null() which has been introduced by: commit 6d7581e62f8be462440d7b22c6361f7c9fa4902b list: introduce list_first_entry_or_null v2: make xfs_ail_min() as a static inline function and move it to xfs_trans_priv.h as per Dave Chinner's comments. Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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ec47eb6b |
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04-Dec-2012 |
Mark Tinguely <tinguely@sgi.com> |
xfs remove the XFS_TRANS_DEBUG routines Remove the XFS_TRANS_DEBUG routines. They are no longer appropriate and have not been used in years Signed-off-by: Mark Tinguely <tinguely@sgi.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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8375f922 |
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28-Jun-2012 |
Brian Foster <bfoster@redhat.com> |
xfs: re-enable xfsaild idle mode and fix associated races xfsaild idle mode logic currently leads to a couple hangs: 1.) If xfsaild is rescheduled in during an incremental scan (i.e., tout != 0) and the target has been updated since the previous run, we can hit the new target and go into idle mode with a still populated ail. 2.) A wake up is only issued when the target is pushed forward. The wake up can race with xfsaild if it is currently in the process of entering idle mode, causing future wake up events to be lost. These hangs have been reproduced and verified as fixed by running xfstests 273 in a loop on a slightly modified upstream kernel. The kernel is modified to re-enable idle mode as previously implemented (when count == 0) and with a revert of commit 670ce93f, which includes performance improvements that make this harder to reproduce. The solution, the algorithm for which has been outlined by Dave Chinner, is to modify xfsaild to enter idle mode only when the ail is empty and the push target has not been moved forward since the last push. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
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60a34607 |
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22-Apr-2012 |
Dave Chinner <dchinner@redhat.com> |
xfs: move xfsagino_t to xfs_types.h Untangle the header file includes a bit by moving the definition of xfs_agino_t to xfs_types.h. This removes the dependency that xfs_ag.h has on xfs_inum.h, meaning we don't need to include xfs_inum.h everywhere we include xfs_ag.h. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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04913fdd |
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22-Apr-2012 |
Dave Chinner <dchinner@redhat.com> |
xfs: pass shutdown method into xfs_trans_ail_delete_bulk xfs_trans_ail_delete_bulk() can be called from different contexts so if the item is not in the AIL we need different shutdown for each context. Pass in the shutdown method needed so the correct action can be taken. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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a8569171 |
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22-Apr-2012 |
Christoph Hellwig <hch@infradead.org> |
xfs: remove some obsolete comments in xfs_trans_ail.c Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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43ff2122 |
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22-Apr-2012 |
Christoph Hellwig <hch@infradead.org> |
xfs: on-stack delayed write buffer lists Queue delwri buffers on a local on-stack list instead of a per-buftarg one, and write back the buffers per-process instead of by waking up xfsbufd. This is now easily doable given that we have very few places left that write delwri buffers: - log recovery: Only done at mount time, and already forcing out the buffers synchronously using xfs_flush_buftarg - quotacheck: Same story. - dquot reclaim: Writes out dirty dquots on the LRU under memory pressure. We might want to look into doing more of this via xfsaild, but it's already more optimal than the synchronous inode reclaim that writes each buffer synchronously. - xfsaild: This is the main beneficiary of the change. By keeping a local list of buffers to write we reduce latency of writing out buffers, and more importably we can remove all the delwri list promotions which were hitting the buffer cache hard under sustained metadata loads. The implementation is very straight forward - xfs_buf_delwri_queue now gets a new list_head pointer that it adds the delwri buffers to, and all callers need to eventually submit the list using xfs_buf_delwi_submit or xfs_buf_delwi_submit_nowait. Buffers that already are on a delwri list are skipped in xfs_buf_delwri_queue, assuming they already are on another delwri list. The biggest change to pass down the buffer list was done to the AIL pushing. Now that we operate on buffers the trylock, push and pushbuf log item methods are merged into a single push routine, which tries to lock the item, and if possible add the buffer that needs writeback to the buffer list. This leads to much simpler code than the previous split but requires the individual IOP_PUSH instances to unlock and reacquire the AIL around calls to blocking routines. Given that xfsailds now also handle writing out buffers, the conditions for log forcing and the sleep times needed some small changes. The most important one is that we consider an AIL busy as long we still have buffers to push, and the other one is that we do increment the pushed LSN for buffers that are under flushing at this moment, but still count them towards the stuck items for restart purposes. Without this we could hammer on stuck items without ever forcing the log and not make progress under heavy random delete workloads on fast flash storage devices. [ Dave Chinner: - rebase on previous patches. - improved comments for XBF_DELWRI_Q handling - fix XBF_ASYNC handling in queue submission (test 106 failure) - rename delwri submit function buffer list parameters for clarity - xfs_efd_item_push() should return XFS_ITEM_PINNED ] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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211e4d43 |
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22-Apr-2012 |
Christoph Hellwig <hch@infradead.org> |
xfs: implement freezing by emptying the AIL Now that we write back all metadata either synchronously or through the AIL we can simply implement metadata freezing in terms of emptying the AIL. The implementation for this is fairly simply and straight-forward: A new routine is added that asks the xfsaild to push the AIL to the end and waits for it to complete and send a wakeup. The routine will then loop if the AIL is not actually empty, and continue to do so until the AIL is compeltely empty. We keep an inode reclaim pass in the freeze process to avoid having memory pressure have to reclaim inodes that require dirtying the filesystem to be reclaimed after the freeze has completed. This means we can also treat unmount in the exact same way as freeze. As an upside we can now remove the radix tree based inode writeback and xfs_unmountfs_writesb. [ Dave Chinner: - Cleaned up commit message. - Added inode reclaim passes back into freeze. - Cleaned up wakeup mechanism to avoid the use of a new sleep counter variable. ] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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1c304625 |
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22-Apr-2012 |
Christoph Hellwig <hch@infradead.org> |
xfs: allow assigning the tail lsn with the AIL lock held Provide a variant of xlog_assign_tail_lsn that has the AIL lock already held. By doing so we do an additional atomic_read + atomic_set under the lock, which comes down to two instructions. Switch xfs_trans_ail_update_bulk and xfs_trans_ail_delete_bulk to the new version to reduce the number of lock roundtrips, and prepare for a new addition that would require a third lock roundtrip in xfs_trans_ail_delete_bulk. This addition is also the reason for slightly rearranging the conditionals and relying on xfs_log_space_wake for checking that the filesystem has been shut down internally. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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cfb7cdca |
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19-Feb-2012 |
Christoph Hellwig <hch@infradead.org> |
xfs: cleanup xfs_log_space_wake Remove the now unused opportunistic parameter, and use the the xlog_writeq_wake and xlog_reserveq_wake helpers now that we don't have to care about the opportunistic wakeups. Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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5b03ff1b |
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19-Feb-2012 |
Christoph Hellwig <hch@infradead.org> |
xfs: remove xfs_trans_unlocked_item There is no reason to wake up log space waiters when unlocking inodes or dquots, and the commit log has no explanation for this function either. Given that we now have exact log space wakeups everywhere we can assume the reason for this function was to paper over log space races in earlier XFS versions. Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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09a423a3 |
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19-Feb-2012 |
Christoph Hellwig <hch@infradead.org> |
xfs: split tail_lsn assignments from log space wakeups Currently xfs_log_move_tail has a tail_lsn argument that is horribly overloaded: it may contain either an actual lsn to assign to the log tail, 0 as a special case to use the last sync LSN, or 1 to indicate that no tail LSN assignment should be performed, and we should opportunisticly wake up at one task waiting for log space even if we did not move the LSN. Remove the tail lsn assigned from xfs_log_move_tail and make the two callers use xlog_assign_tail_lsn instead of the current variant of partially using the code in xfs_log_move_tail and partially opencoding it. Note that means we grow an addition lock roundtrip on the AIL lock for each bulk update or delete, which is still far less than what we had before introducing the bulk operations. If this proves to be a problem we can still add a variant of xlog_assign_tail_lsn that expects the lock to be held already. Also rename the remainder of xfs_log_move_tail to xfs_log_space_wake as that name describes its functionality much better. Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
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9e4c109a |
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11-Oct-2011 |
Christoph Hellwig <hch@infradead.org> |
xfs: add AIL pushing tracepoints Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
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2900b339 |
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18-Oct-2011 |
Alex Elder <aelder@sgi.com> |
xfs: put in missed fix for merge problem I intended to do this as part of fixing part of the conflict with the merge with Linus' tree, but evidently it didn't get included in the commit. Signed-off-by: Alex Elder <aelder@sgi.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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670ce93f |
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29-Sep-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: reduce the number of log forces from tail pushing The AIL push code will issue a log force on ever single push loop that it exits and has encountered pinned items. It doesn't rescan these pinned items until it revisits the AIL from the start. Hence we only need to force the log once per walk from the start of the AIL to the target LSN. This results in numbers like this: xs_push_ail_flush..... 1456 xs_log_force......... 1485 For an 8-way 50M inode create workload - almost all the log forces are coming from the AIL pushing code. Reduce the number of log forces by only forcing the log if the previous walk found pinned buffers. This reduces the numbers to: xs_push_ail_flush..... 665 xs_log_force......... 682 For the same test. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
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0030807c |
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11-Oct-2011 |
Christoph Hellwig <hch@infradead.org> |
xfs: revert to using a kthread for AIL pushing Currently we have a few issues with the way the workqueue code is used to implement AIL pushing: - it accidentally uses the same workqueue as the syncer action, and thus can be prevented from running if there are enough sync actions active in the system. - it doesn't use the HIGHPRI flag to queue at the head of the queue of work items At this point I'm not confident enough in getting all the workqueue flags and tweaks right to provide a perfectly reliable execution context for AIL pushing, which is the most important piece in XFS to make forward progress when the log fills. Revert back to use a kthread per filesystem which fixes all the above issues at the cost of having a task struct and stack around for each mounted filesystem. In addition this also gives us much better ways to diagnose any issues involving hung AIL pushing and removes a small amount of code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Stefan Priebe <s.priebe@profihost.ag> Tested-by: Stefan Priebe <s.priebe@profihost.ag> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
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17b38471 |
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11-Oct-2011 |
Christoph Hellwig <hch@infradead.org> |
xfs: force the log if we encounter pinned buffers in .iop_pushbuf We need to check for pinned buffers even in .iop_pushbuf given that inode items flush into the same buffers that may be pinned directly due operations on the unlinked inode list operating directly on buffers. To do this add a return value to .iop_pushbuf that tells the AIL push about this and use the existing log force mechanisms to unpin it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Stefan Priebe <s.priebe@profihost.ag> Tested-by: Stefan Priebe <s.priebe@profihost.ag> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
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bc6e588a |
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11-Oct-2011 |
Christoph Hellwig <hch@infradead.org> |
xfs: do not update xa_last_pushed_lsn for locked items If an item was locked we should not update xa_last_pushed_lsn and thus skip it when restarting the AIL scan as we need to be able to lock and write it out as soon as possible. Otherwise heavy lock contention might starve AIL pushing too easily, especially given the larger backoff once we moved xa_last_pushed_lsn all the way to the target lsn. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Stefan Priebe <s.priebe@profihost.ag> Tested-by: Stefan Priebe <s.priebe@profihost.ag> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
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e44f4112 |
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22-Jul-2011 |
Alex Elder <aelder@sgi.com> |
xfs: set cursor in xfs_ail_splice() even when AIL was empty In xfs_ail_splice(), if a cursor is provided it is updated to point to the last item on the list being spliced into the AIL. But if the AIL was found to be empty, the cursor (if provided) is just initialized instead. There is no reason the empty AIL case needs to be treated any differently. And treating it the same way allows this code to be rearranged a bit, with a somewhat tidier result. Signed-off-by: Alex Elder <aelder@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
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af3e4022 |
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17-Jul-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: convert AIL cursors to use struct list_head The list of active AIL cursors uses a roll-your-own linked list with special casing for the AIL push cursor. Simplify this code by replacing the list with standard struct list_head lists, and use a separate list_head to track the active cursors. This allows us to treat the AIL push cursor as a generic cursor rather than as a special case, further simplifying the code. Further, fix the duplicate push cursor initialisation that the special case handling was hiding, and clean up all the comments around the active cursor list handling. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
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16b59029 |
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17-Jul-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: remove confusing ail cursor wrapper xfs_trans_ail_cursor_set() doesn't set the cursor to the current log item, it sets it to the next item. There is already a function for doing this - xfs_trans_ail_cursor_next() - and the _set function is simply a two line wrapper. Remove it and open code the setting of the cursor in the two locations that call it to remove the confusion. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
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1d8c95a3 |
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17-Jul-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: use a cursor for bulk AIL insertion Delayed logging can insert tens of thousands of log items into the AIL at the same LSN. When the committing of log commit records occur, we can get insertions occurring at an LSN that is not at the end of the AIL. If there are thousands of items in the AIL on the tail LSN, each insertion has to walk the AIL to find the correct place to insert the new item into the AIL. This can consume large amounts of CPU time and block other operations from occurring while the traversals are in progress. To avoid this repeated walk, use a AIL cursor to record where we should be inserting the new items into the AIL without having to repeat the walk. The cursor infrastructure already provides this functionality for push walks, so is a simple extension of existing code. While this will not avoid the initial walk, it will avoid repeating it tens of thousands of times during a single checkpoint commit. This version includes logic improvements from Christoph Hellwig. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
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7ac95657 |
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05-May-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: fix race condition in AIL push trigger The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. One is caused by a race condition in determining whether there is a psh in progress or not. The XFS_AIL_PUSHING_BIT is used to determine whether a push is currently in progress. When the AIL push work completes, it checked whether the target changed and cleared the PUSHING bit to allow a new push to be requeued. The race condition is as follows: Thread 1 push work smp_wmb() smp_rmb() check ailp->xa_target unchanged update ailp->xa_target test/set PUSHING bit does not queue clear PUSHING bit does not requeue Now that the push target is updated, new attempts to push the AIL will not trigger as the push target will be the same, and hence despite trying to push the AIL we won't ever wake it again. The fix is to ensure that the AIL push work clears the PUSHING bit before it checks if the target is unchanged. As a result, both push triggers operate on the same test/set bit criteria, so even if we race in the push work and miss the target update, the thread requesting the push will still set the PUSHING bit and queue the push work to occur. For safety sake, the same queue check is done if the push work detects the target change, though only one of the two will will queue new work due to the use of test_and_set_bit() checks. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> (cherry picked from commit e4d3c4a43b595d5124ae824d300626e6489ae857)
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fe0da767 |
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05-May-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: make AIL target updates and compares 32bit safe. The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. One of the problems noticed was that updates of the push target are not 32 bit safe as the target is a 64 bit value. We cannot copy a 64 bit LSN without the possibility of corrupting the result when racing with another updating thread. We have function to do this update safely without needing to care about 32/64 bit issues - xfs_trans_ail_copy_lsn() - so use that when updating the AIL push target. Also move the reading of the target in the push work inside the AIL lock, and use XFS_LSN_CMP() for the unlocked comparison during work termination to close read holes as well. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> (cherry picked from commit fd5670f22fce247754243cf2ed41941e5762d990)
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50e86686 |
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05-May-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: always push the AIL to the target The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. One of the problems discovered is a target mismatch between the item pushing loop and the target itself. The push trigger checks for the target increasing (i.e. new target > current) while the push loop only pushes items that have a LSN < current. As a result, we can get the situation where the push target is X, the items at the tail of the AIL have LSN X and they don't get pushed. The push work then completes thinking it is done, and cannot be restarted until the push target increases to >= X + 1. If the push target then never increases (because the tail is not moving), then we never run the push work again and we stall. Fix it by making sure log items with a LSN that matches the target exactly are pushed during the loop. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> (cherry picked from commit cb64026b6e8af50db598ec7c3f59d504259b00bb)
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9e7004e7 |
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05-May-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: exit AIL push work correctly when AIL is empty The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. The main cause is a regression where a work exit path fails to clear the PUSHING state and recheck the target correctly. Make both exit paths do the same PUSHING bit clearing and target checking when the "no more work to be done" condition is hit. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> (cherry picked from commit ea35a20021f8497390d05b93271b4d675516c654)
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e4d3c4a4 |
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05-May-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: fix race condition in AIL push trigger The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. One is caused by a race condition in determining whether there is a psh in progress or not. The XFS_AIL_PUSHING_BIT is used to determine whether a push is currently in progress. When the AIL push work completes, it checked whether the target changed and cleared the PUSHING bit to allow a new push to be requeued. The race condition is as follows: Thread 1 push work smp_wmb() smp_rmb() check ailp->xa_target unchanged update ailp->xa_target test/set PUSHING bit does not queue clear PUSHING bit does not requeue Now that the push target is updated, new attempts to push the AIL will not trigger as the push target will be the same, and hence despite trying to push the AIL we won't ever wake it again. The fix is to ensure that the AIL push work clears the PUSHING bit before it checks if the target is unchanged. As a result, both push triggers operate on the same test/set bit criteria, so even if we race in the push work and miss the target update, the thread requesting the push will still set the PUSHING bit and queue the push work to occur. For safety sake, the same queue check is done if the push work detects the target change, though only one of the two will will queue new work due to the use of test_and_set_bit() checks. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com>
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fd5670f2 |
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05-May-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: make AIL target updates and compares 32bit safe. The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. One of the problems noticed was that updates of the push target are not 32 bit safe as the target is a 64 bit value. We cannot copy a 64 bit LSN without the possibility of corrupting the result when racing with another updating thread. We have function to do this update safely without needing to care about 32/64 bit issues - xfs_trans_ail_copy_lsn() - so use that when updating the AIL push target. Also move the reading of the target in the push work inside the AIL lock, and use XFS_LSN_CMP() for the unlocked comparison during work termination to close read holes as well. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com>
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cb64026b |
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05-May-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: always push the AIL to the target The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. One of the problems discovered is a target mismatch between the item pushing loop and the target itself. The push trigger checks for the target increasing (i.e. new target > current) while the push loop only pushes items that have a LSN < current. As a result, we can get the situation where the push target is X, the items at the tail of the AIL have LSN X and they don't get pushed. The push work then completes thinking it is done, and cannot be restarted until the push target increases to >= X + 1. If the push target then never increases (because the tail is not moving), then we never run the push work again and we stall. Fix it by making sure log items with a LSN that matches the target exactly are pushed during the loop. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com>
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ea35a200 |
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05-May-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: exit AIL push work correctly when AIL is empty The recent conversion of the xfsaild functionality to a work queue introduced a hard-to-hit log space grant hang. The main cause is a regression where a work exit path fails to clear the PUSHING state and recheck the target correctly. Make both exit paths do the same PUSHING bit clearing and target checking when the "no more work to be done" condition is hit. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com>
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#
fd074841 |
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07-Apr-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: push the AIL from memory reclaim and periodic sync When we are short on memory, we want to expedite the cleaning of dirty objects. Hence when we run short on memory, we need to kick the AIL flushing into action to clean as many dirty objects as quickly as possible. To implement this, sample the lsn of the log item at the head of the AIL and use that as the push target for the AIL flush. Further, we keep items in the AIL that are dirty that are not tracked any other way, so we can get objects sitting in the AIL that don't get written back until the AIL is pushed. Hence to get the filesystem to the idle state, we might need to push the AIL to flush out any remaining dirty objects sitting in the AIL. This requires the same push mechanism as the reclaim push. This patch also renames xfs_trans_ail_tail() to xfs_ail_min_lsn() to match the new xfs_ail_max_lsn() function introduced in this patch. Similarly for xfs_trans_ail_push -> xfs_ail_push. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Alex Elder <aelder@sgi.com>
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#
cd4a3c50 |
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07-Apr-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: clean up code layout in xfs_trans_ail.c This patch rearranges the location of functions in xfs_trans_ail.c to remove the need for forward declarations of those functions in preparation for adding new functions without the need for forward declarations. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Alex Elder <aelder@sgi.com>
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#
0bf6a5bd |
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07-Apr-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: convert the xfsaild threads to a workqueue Similar to the xfssyncd, the per-filesystem xfsaild threads can be converted to a global workqueue and run periodically by delayed works. This makes sense for the AIL pushing because it uses variable timeouts depending on the work that needs to be done. By removing the xfsaild, we simplify the AIL pushing code and remove the need to spread the code to implement the threading and pushing across multiple files. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com>
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#
6a19d939 |
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06-Mar-2011 |
Dave Chinner <dchinner@redhat.com> |
xfs: convert xfs_cmn_err to xfs_alert_tag Continue the conversion of the old cmn_err interface be converting all the conditional panic tag errors to xfs_alert_tag() and then removing xfs_cmn_err(). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Alex Elder <aelder@sgi.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
9552e7f2 |
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19-Dec-2010 |
Dave Chinner <dchinner@redhat.com> |
xfs: use AIL bulk delete function to implement single delete We now have two copies of AIL delete operations that are mostly duplicate functionality. The single log item deletes can be implemented via the bulk updates by turning xfs_trans_ail_delete() into a simple wrapper. This removes all the duplicate delete functionality and associated helpers. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
e6059949 |
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19-Dec-2010 |
Dave Chinner <dchinner@redhat.com> |
xfs: use AIL bulk update function to implement single updates We now have two copies of AIL insert operations that are mostly duplicate functionality. The single log item updates can be implemented via the bulk updates by turning xfs_trans_ail_update() into a simple wrapper. This removes all the duplicate insert functionality and associated helpers. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
30136832 |
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19-Dec-2010 |
Dave Chinner <dchinner@redhat.com> |
xfs: remove all the inodes on a buffer from the AIL in bulk When inode buffer IO completes, usually all of the inodes are removed from the AIL. This involves processing them one at a time and taking the AIL lock once for every inode. When all CPUs are processing inode IO completions, this causes excessive amount sof contention on the AIL lock. Instead, change the way we process inode IO completion in the buffer IO done callback. Allow the inode IO done callback to walk the list of IO done callbacks and pull all the inodes off the buffer in one go and then process them as a batch. Once all the inodes for removal are collected, take the AIL lock once and do a bulk removal operation to minimise traffic on the AIL lock. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
0e57f6a3 |
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19-Dec-2010 |
Dave Chinner <dchinner@redhat.com> |
xfs: bulk AIL insertion during transaction commit When inserting items into the AIL from the transaction committed callbacks, we take the AIL lock for every single item that is to be inserted. For a CIL checkpoint commit, this can be tens of thousands of individual inserts, yet almost all of the items will be inserted at the same point in the AIL because they have the same index. To reduce the overhead and contention on the AIL lock for such operations, introduce a "bulk insert" operation which allows a list of log items with the same LSN to be inserted in a single operation via a list splice. To do this, we need to pre-sort the log items being committed into a temporary list for insertion. The complexity is that not every log item will end up with the same LSN, and not every item is actually inserted into the AIL. Items that don't match the commit LSN will be inserted and unpinned as per the current one-at-a-time method (relatively rare), while items that are not to be inserted will be unpinned and freed immediately. Items that are to be inserted at the given commit lsn are placed in a temporary array and inserted into the AIL in bulk each time the array fills up. As a result of this, we trade off AIL hold time for a significant reduction in traffic. lock_stat output shows that the worst case hold time is unchanged, but contention from AIL inserts drops by an order of magnitude and the number of lock traversal decreases significantly. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
eb3efa12 |
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02-Dec-2010 |
Dave Chinner <dchinner@redhat.com> |
xfs: clean up xfs_ail_delete() xfs_ail_delete() has a needlessly complex interface. It returns the log item that was passed in for deletion (which the callers then assert is identical to the one passed in), and callers of xfs_ail_delete() still need to invalidate current traversal cursors. Make xfs_ail_delete() return void, move the cursor invalidation inside it, and clean up the callers just to use the log item pointer they passed in. While cleaning up, remove the messy and unnecessary "/* ARGUSED */" comments around all these functions. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
288699fe |
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23-Jun-2010 |
Christoph Hellwig <hch@infradead.org> |
xfs: drop dmapi hooks Dmapi support was never merged upstream, but we still have a lot of hooks bloating XFS for it, all over the fast pathes of the filesystem. This patch drops over 700 lines of dmapi overhead. If we'll ever get HSM support in mainline at least the namespace events can be done much saner in the VFS instead of the individual filesystem, so it's not like this is much help for future work. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
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#
d808f617 |
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01-Feb-2010 |
Dave Chinner <david@fromorbit.com> |
xfs: Don't issue buffer IO direct from AIL push V2 All buffers logged into the AIL are marked as delayed write. When the AIL needs to push the buffer out, it issues an async write of the buffer. This means that IO patterns are dependent on the order of buffers in the AIL. Instead of flushing the buffer, promote the buffer in the delayed write list so that the next time the xfsbufd is run the buffer will be flushed by the xfsbufd. Return the state to the xfsaild that the buffer was promoted so that the xfsaild knows that it needs to cause the xfsbufd to run to flush the buffers that were promoted. Using the xfsbufd for issuing the IO allows us to dispatch all buffer IO from the one queue. This means that we can make much more enlightened decisions on what order to flush buffers to disk as we don't have multiple places issuing IO. Optimisations to xfsbufd will be in a future patch. Version 2 - kill XFS_ITEM_FLUSHING as it is now unused. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
a14a348b |
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19-Jan-2010 |
Christoph Hellwig <hch@infradead.org> |
xfs: cleanup up xfs_log_force calling conventions Remove the XFS_LOG_FORCE argument which was always set, and the XFS_LOG_URGE define, which was never used. Split xfs_log_force into a two helpers - xfs_log_force which forces the whole log, and xfs_log_force_lsn which forces up to the specified LSN. The underlying implementations already were entirely separate, as were the users. Also re-indent the new _xfs_log_force/_xfs_log_force which previously had a weird coding style. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
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#
453eac8a |
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11-Jan-2010 |
Dave Chinner <david@fromorbit.com> |
xfs: Don't wake the aild once per second Now that the AIL push algorithm is traversal safe, we don't need a watchdog function in the xfsaild to catch pushes that fail to make progress. Remove the watchdog timeout and make pushes purely driven by demand. This will remove the once-per-second wakeup that is seen when the filesystem is idle and make laptop power misers happy. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
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#
6c06f072 |
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16-Nov-2009 |
Nathaniel W. Turner <nate@houseofnate.net> |
xfs: copy li_lsn before dropping AIL lock Access to log items on the AIL is generally protected by m_ail_lock; this is particularly needed when we're getting or setting the 64-bit li_lsn on a 32-bit platform. This patch fixes a couple places where we were accessing the log item after dropping the AIL lock on 32-bit machines. This can result in a partially-zeroed log->l_tail_lsn if xfs_trans_ail_delete is racing with xfs_trans_ail_update, and in at least some cases, this can leave the l_tail_lsn with a zero cycle number, which means xlog_space_left will think the log is full (unless CONFIG_XFS_DEBUG is set, in which case we'll trip an ASSERT), leading to processes stuck forever in xlog_grant_log_space. Thanks to Adrian VanderSpek for first spotting the race potential and to Dave Chinner for debug assistance. Signed-off-by: Nathaniel W. Turner <nate@houseofnate.net> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
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#
9da096fd |
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29-Mar-2009 |
Malcolm Parsons <malcolm.parsons@gmail.com> |
xfs: fix various typos Signed-off-by: Malcolm Parsons <malcolm.parsons@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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#
7ee49acf |
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30-Oct-2008 |
David Chinner <david@fromorbit.com> |
[XFS] correctly select first log item to push Under heavy metadata load we are seeing log hangs. The AIL has items in it ready to be pushed, and they are within the push target window. However, we are not pushing them when the last pushed LSN is less than the LSN of the first log item on the AIL. This is a regression introduced by the AIL push cursor modifications. SGI-PV: 987246 SGI-Modid: xfs-linux-melb:xfs-kern:32409a Signed-off-by: David Chinner <david@fromorbit.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
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#
783a2f65 |
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30-Oct-2008 |
David Chinner <david@fromorbit.com> |
[XFS] Finish removing the mount pointer from the AIL API Change all the remaining AIL API functions that are passed struct xfs_mount pointers to pass pointers directly to the struct xfs_ail being used. With this conversion, all external access to the AIL is via the struct xfs_ail. Hence the operation and referencing of the AIL is almost entirely independent of the xfs_mount that is using it - it is now much more tightly tied to the log and the items it is tracking in the log than it is tied to the xfs_mount. SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32353a Signed-off-by: David Chinner <david@fromorbit.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org>
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#
c7e8f268 |
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30-Oct-2008 |
David Chinner <david@fromorbit.com> |
[XFS] Move the AIL lock into the struct xfs_ail Bring the ail lock inside the struct xfs_ail. This means the AIL can be entirely manipulated via the struct xfs_ail rather than needing both the struct xfs_mount and the struct xfs_ail. SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32350a Signed-off-by: David Chinner <david@fromorbit.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org>
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#
5b00f14f |
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30-Oct-2008 |
David Chinner <david@fromorbit.com> |
[XFS] move the AIl traversal over to a consistent interface With the new cursor interface, it makes sense to make all the traversing code use the cursor interface and make the old one go away. This means more of the AIL interfacing is done by passing struct xfs_ail pointers around the place instead of struct xfs_mount pointers. We can replace the use of xfs_trans_first_ail() in xfs_log_need_covered() as it is only checking if the AIL is empty. We can do that with a call to xfs_trans_ail_tail() instead, where a zero LSN returned indicates and empty AIL... SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32348a Signed-off-by: David Chinner <david@fromorbit.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org>
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#
27d8d5fe |
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30-Oct-2008 |
David Chinner <david@fromorbit.com> |
[XFS] Use a cursor for AIL traversal. To replace the current generation number ensuring sanity of the AIL traversal, replace it with an external cursor that is linked to the AIL. Basically, we store the next item in the cursor whenever we want to drop the AIL lock to do something to the current item. When we regain the lock. the current item may already be free, so we can't reference it, but the next item in the traversal is already held in the cursor. When we move or delete an object, we search all the active cursors and if there is an item match we clear the cursor(s) that point to the object. This forces the traversal to restart transparently. We don't invalidate the cursor on insert because the cursor still points to a valid item. If the intem is inserted between the current item and the cursor it does not matter; the traversal is considered to be past the insertion point so it will be picked up in the next traversal. Hence traversal restarts pretty much disappear altogether with this method of traversal, which should substantially reduce the overhead of pushing on a busy AIL. Version 2 o add restart logic o comment cursor interface o minor cleanups SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32347a Signed-off-by: David Chinner <david@fromorbit.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org>
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#
82fa9012 |
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30-Oct-2008 |
David Chinner <david@fromorbit.com> |
[XFS] Allocate the struct xfs_ail Rather than embedding the struct xfs_ail in the struct xfs_mount, allocate it during AIL initialisation. Add a back pointer to the struct xfs_ail so that we can pass around the xfs_ail and still be able to access the xfs_mount if need be. This is th first step involved in isolating the AIL implementation from the surrounding filesystem code. SGI-PV: 988143 SGI-Modid: xfs-linux-melb:xfs-kern:32346a Signed-off-by: David Chinner <david@fromorbit.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org>
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#
34a622b2 |
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09-Apr-2008 |
Harvey Harrison <harvey.harrison@gmail.com> |
[XFS] replace remaining __FUNCTION__ occurrences __FUNCTION__ is gcc-specific, use __func__ SGI-PV: 976035 SGI-Modid: xfs-linux-melb:xfs-kern:30775a Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
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#
535f6b37 |
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27-Mar-2008 |
Josef 'Jeff' Sipek <jeffpc@josefsipek.net> |
[XFS] Replace custom AIL linked-list code with struct list_head Replace the xfs_ail_entry_t with a struct list_head and clean the surrounding code up. Also fixes a livelock in xfs_trans_first_push_ail() by terminating the loop at the head of the list correctly. SGI-PV: 978682 SGI-Modid: xfs-linux-melb:xfs-kern:30636a Signed-off-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
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#
92d9cd10 |
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05-Mar-2008 |
David Chinner <dgc@sgi.com> |
[XFS] 977545 977545 977545 977545 977545 977545 xfsaild causing too many wakeups Idle state is not being detected properly by the xfsaild push code. The current idle state is detected by an empty list which may never happen with mostly idle filesystem or one using lazy superblock counters. A single dirty item in the list that exists beyond the push target can result repeated looping attempting to push up to the target because it fails to check if the push target has been acheived or not. Fix by considering a dirty list with everything past the target as an idle state and set the timeout appropriately. SGI-PV: 977545 SGI-Modid: xfs-linux-melb:xfs-kern:30532a Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
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#
de08dbc1 |
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04-Feb-2008 |
David Chinner <dgc@sgi.com> |
[XFS] Make xfs_ail_check check less by default Checking the entire AIL on every insert and remove is prohibitively expensive - the sustained sequntial create rate on a single disk drops from about 1800/s to 60/s because of this checking resulting in the xfslogd becoming cpu bound. By default on debug builds, only check the next and previous entries in the list to ensure they are ordered correctly. If you really want, define XFS_TRANS_DEBUG to use the old behaviour. SGI-PV: 972759 SGI-Modid: xfs-linux-melb:xfs-kern:30372a Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
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#
249a8c11 |
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04-Feb-2008 |
David Chinner <dgc@sgi.com> |
[XFS] Move AIL pushing into it's own thread When many hundreds to thousands of threads all try to do simultaneous transactions and the log is in a tail-pushing situation (i.e. full), we can get multiple threads walking the AIL list and contending on the AIL lock. The AIL push is, in effect, a simple I/O dispatch algorithm complicated by the ordering constraints placed on it by the transaction subsystem. It really does not need multiple threads to push on it - even when only a single CPU is pushing the AIL, it can push the I/O out far faster that pretty much any disk subsystem can handle. So, to avoid contention problems stemming from multiple list walkers, move the list walk off into another thread and simply provide a "target" to push to. When a thread requires a push, it sets the target and wakes the push thread, then goes to sleep waiting for the required amount of space to become available in the log. This mechanism should also be a lot fairer under heavy load as the waiters will queue in arrival order, rather than queuing in "who completed a push first" order. Also, by moving the pushing to a separate thread we can do more effectively overload detection and prevention as we can keep context from loop iteration to loop iteration. That is, we can push only part of the list each loop and not have to loop back to the start of the list every time we run. This should also help by reducing the number of items we try to lock and/or push items that we cannot move. Note that this patch is not intended to solve the inefficiencies in the AIL structure and the associated issues with extremely large list contents. That needs to be addresses separately; parallel access would cause problems to any new structure as well, so I'm only aiming to isolate the structure from unbounded parallelism here. SGI-PV: 972759 SGI-Modid: xfs-linux-melb:xfs-kern:30371a Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
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#
287f3dad |
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11-Oct-2007 |
Donald Douwsma <donaldd@sgi.com> |
[XFS] Unwrap AIL_LOCK SGI-PV: 970382 SGI-Modid: xfs-linux-melb:xfs-kern:29739a Signed-off-by: Donald Douwsma <donaldd@sgi.com> Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Signed-off-by: Tim Shimmin <tes@sgi.com>
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#
da353b0d |
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27-Aug-2007 |
David Chinner <dgc@sgi.com> |
[XFS] Radix tree based inode caching One of the perpetual scaling problems XFS has is indexing it's incore inodes. We currently uses hashes and the default hash sizes chosen can only ever be a tradeoff between memory consumption and the maximum realistic size of the cache. As a result, anyone who has millions of inodes cached on a filesystem needs to tunes the size of the cache via the ihashsize mount option to allow decent scalability with inode cache operations. A further problem is the separate inode cluster hash, whose size is based on the ihashsize but is smaller, and so under certain conditions (sparse cluster cache population) this can become a limitation long before the inode hash is causing issues. The following patchset removes the inode hash and cluster hash and replaces them with radix trees to avoid the scalability limitations of the hashes. It also reduces the size of the inodes by 3 pointers.... SGI-PV: 969561 SGI-Modid: xfs-linux-melb:xfs-kern:29481a Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Tim Shimmin <tes@sgi.com>
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#
7666ab5f |
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10-Feb-2007 |
Vlad Apostolov <vapo@sgi.com> |
[XFS] Workaround log space issue by increasing XFS_TRANS_PUSH_AIL_RESTARTS SGI-PV: 959264 SGI-Modid: xfs-linux-melb:xfs-kern:27750a Signed-off-by: Vlad Apostolov <vapo@sgi.com> Signed-off-by: David Chatterton <chatz@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
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#
22d91f65 |
|
27-Sep-2006 |
Josh Triplett <josh@joshtriplett.org> |
[XFS] Add lock annotations to xfs_trans_update_ail and xfs_trans_delete_ail xfs_trans_update_ail and xfs_trans_delete_ail get called with the AIL lock held, and release it. Add lock annotations to these two functions so that sparse can check callers for lock pairing, and so that sparse will not complain about these functions since they intentionally use locks in this manner. SGI-PV: 954580 SGI-Modid: xfs-linux-melb:xfs-kern:26807a Signed-off-by: Josh Triplett <josh@freedesktop.org> Signed-off-by: Nathan Scott <nathans@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
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#
f6c2d1fa |
|
19-Jun-2006 |
Nathan Scott <nathans@sgi.com> |
[XFS] Remove version 1 directory code. Never functioned on Linux, just pure bloat. SGI-PV: 952969 SGI-Modid: xfs-linux-melb:xfs-kern:26251a Signed-off-by: Nathan Scott <nathans@sgi.com>
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#
7d04a335 |
|
08-Jun-2006 |
Nathan Scott <nathans@sgi.com> |
[XFS] Shutdown the filesystem if all device paths have gone. Made shutdown vop flags consistent with sync vop flags declarations too. SGI-PV: 939911 SGI-Modid: xfs-linux-melb:xfs-kern:26096a Signed-off-by: Nathan Scott <nathans@sgi.com>
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#
7b718769 |
|
01-Nov-2005 |
Nathan Scott <nathans@sgi.com> |
[XFS] Update license/copyright notices to match the prefered SGI boilerplate. SGI-PV: 913862 SGI-Modid: xfs-linux:xfs-kern:23903a Signed-off-by: Nathan Scott <nathans@sgi.com>
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#
a844f451 |
|
01-Nov-2005 |
Nathan Scott <nathans@sgi.com> |
[XFS] Remove xfs_macros.c, xfs_macros.h, rework headers a whole lot. SGI-PV: 943122 SGI-Modid: xfs-linux:xfs-kern:23901a Signed-off-by: Nathan Scott <nathans@sgi.com>
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#
6f948fbd |
|
02-Sep-2005 |
Tim Shimmin <tes@sgi.com> |
[XFS] Need to unlock the AIL before calling xfs_force_shutdown() because when it goes to force out the log, and get the tail lsn, it will want to get the AIL lock. SGI-PV: 940076 SGI-Modid: xfs-linux:xfs-kern:23260a Signed-off-by: Tim Shimmin <tes@sgi.com> Signed-off-by: Nathan Scott <nathans@sgi.com>
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#
1da177e4 |
|
16-Apr-2005 |
Linus Torvalds <torvalds@ppc970.osdl.org> |
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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