History log of /linux-master/tools/perf/Documentation/perf-buildid-list.txt
Revision Date Author Comments
# a6bd98c4 29-Jun-2022 Blake Jones <blakejones@google.com>

perf buildid-list: Add a "-m" option to show kernel and modules build-ids

This new option displays all of the information needed to do external
BuildID-based symbolization of kernel stack traces, such as those collected
by bpf_get_stackid().

For each kernel module plus the main kernel, it displays the BuildID,
the start and end virtual addresses of that module's text range (rounded
out to page boundaries), and the pathname of the module.

When run as a non-privileged user, the actual addresses of the modules'
text ranges are not available, so the tools displays "0, <text length>" for
kernel modules and "0, 0xffffffffffffffff" for the kernel itself.

Sample output:

root# perf buildid-list -m
cf6df852fd4da122d616153353cc8f560fd12fe0 ffffffffa5400000 ffffffffa6001e27 [kernel.kallsyms]
1aa7209aa2acb067d66ed6cf7676d65066384d61 ffffffffc0087000 ffffffffc008b000 /lib/modules/5.15.15-1rodete2-amd64/kernel/crypto/sha512_generic.ko
3857815b5bf0183697b68f8fe0ea06121644041e ffffffffc008c000 ffffffffc0098000 /lib/modules/5.15.15-1rodete2-amd64/kernel/arch/x86/crypto/sha512-ssse3.ko
4081fde0bca2bc097cb3e9d1efcb836047d485f1 ffffffffc0099000 ffffffffc009f000 /lib/modules/5.15.15-1rodete2-amd64/kernel/drivers/acpi/button.ko
1ef81ba4890552ea6b0314f9635fc43fc8cef568 ffffffffc00a4000 ffffffffc00aa000 /lib/modules/5.15.15-1rodete2-amd64/kernel/crypto/cryptd.ko
cc5c985506cb240d7d082b55ed260cbb851f983e ffffffffc00af000 ffffffffc00b6000 /lib/modules/5.15.15-1rodete2-amd64/kernel/drivers/i2c/busses/i2c-piix4.ko
[...]

Committer notes:

u64 formatter should be PRIx64 for printing as hex numbers, fix this:

28 5.28 debian:experimental-x-mips : FAIL gcc version 11.2.0 (Debian 11.2.0-18)
builtin-buildid-list.c: In function 'buildid__map_cb':
builtin-buildid-list.c:32:24: error: format '%lx' expects argument of type 'long unsigned int', but argument 3 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=]
32 | printf("%s %16lx %16lx", bid_buf, map->start, map->end);
| ~~~~^ ~~~~~~~~~~
| | |
| long unsigned int u64 {aka long long unsigned int}
| %16llx
builtin-buildid-list.c:32:30: error: format '%lx' expects argument of type 'long unsigned int', but argument 4 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=]
32 | printf("%s %16lx %16lx", bid_buf, map->start, map->end);
| ~~~~^ ~~~~~~~~
| | |
| long unsigned int u64 {aka long long unsigned int}
| %16llx
cc1: all warnings being treated as errors

Signed-off-by: Blake Jones <blakejones@google.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220629213632.3899212-1-blakejones@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# efad1415 07-Dec-2011 Robert Richter <robert.richter@amd.com>

perf report: Accept fifos as input file

The default input file for perf report is not handled the same way as
perf record does it for its output file. This leads to unexpected
behavior of perf report, etc. E.g.:

# perf record -a -e cpu-cycles sleep 2 | perf report | cat
failed to open perf.data: No such file or directory (try 'perf record' first)

While perf record writes to a fifo, perf report expects perf.data to be
read. This patch changes this to accept fifos as input file.

Applies to the following commands:

perf annotate
perf buildid-list
perf evlist
perf kmem
perf lock
perf report
perf sched
perf script
perf timechart

Also fixes char const* -> const char* type declaration for filename
strings.

v2:
* Prevent potential null pointer access to input_name in
builtin-report.c. Needed due to removal of patch "perf report: Setup
browser if stdout is a pipe"

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-5-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 7a6f205d 29-Aug-2011 Arnaldo Carvalho de Melo <acme@redhat.com>

perf buildid-list: Support showing the build id in an ELF file

Try first reading the build id, validating that it is an ELF file, etc.
Cheap as libelf will bail out as soon as the magic number check fails.

Useful when investigating debuginfo packaging problems like this one:

[root@emilia ~]# perf buildid-list -i /usr/lib/debug/lib/modules/`uname -r`/vmlinux
77bb4ea591a602d455ace759a377c9adfff1aba3
[root@emilia ~]# perf buildid-list -k
07b0c016a2b30004e86132d0239945b1e88f5d75
[root@emilia ~]#

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-4elot9oxwa0rr0d90dshca3a@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# f2add9cd 29-Aug-2011 Arnaldo Carvalho de Melo <acme@redhat.com>

perf buildid-list: Add option to show the running kernel build id

[root@emilia ~]# perf buildid-list -k
07b0c016a2b30004e86132d0239945b1e88f5d75

Useful when diagnosing build id problems in debuginfo packages, etc.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-po1bl7acn6e1hhne90opmvtl@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# b6a535db 30-Nov-2010 Shawn Bohrer <shawn.bohrer@gmail.com>

perf buildid-list: Document missing options

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1291168642-11402-3-git-send-email-shawn.bohrer@gmail.com>
Signed-off-by: Shawn Bohrer <shawn.bohrer@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 1124ba73 16-Nov-2009 Arnaldo Carvalho de Melo <acme@redhat.com>

perf buildid-list: Always show the DSO name

Porcelain can ignore it, humans can make more sense of it.

Suggested-by: Frederic Weisbecker <fweisbec@gmail.com>
Suggested-by: Ingo Molnar <mingo@elte.hu>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1258415125-15019-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


# c34984b2 16-Nov-2009 Arnaldo Carvalho de Melo <acme@redhat.com>

perf buildid-list: New plumbing command

With this we can list the buildids in a perf.data file so that
we can pipe them to other, distro specific tools that from the
buildids can figure out separate packages (foo-debuginfo) where
we can find the matching symtabs so that perf report can do its
job.

E.g:

[acme@doppio linux-2.6-tip]$ perf buildid-list | head -5
8e08b117e5458ad3f85da16d42d0fc5cd21c5869
520c2387a587cc5acfcf881e27dba1caaeab4b1f
ec8dd400904ddfcac8b1c343263a790f977159dc
7caedbca5a6d8ab39a7fe44bd28c07d3e14a3f3f
379bb828fd08859dbea73279f04abefabc95a6a3
[acme@doppio linux-2.6-tip]$ perf buildid-list -v | head -5
8e08b117e5458ad3f85da16d42d0fc5cd21c5869 /sbin/init
520c2387a587cc5acfcf881e27dba1caaeab4b1f /lib64/ld-2.10.1.so
ec8dd400904ddfcac8b1c343263a790f977159dc /lib64/libc-2.10.1.so
7caedbca5a6d8ab39a7fe44bd28c07d3e14a3f3f /sbin/udevd
379bb828fd08859dbea73279f04abefabc95a6a3 /lib64/libdl-2.10.1.so
[acme@doppio linux-2.6-tip]$

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1258396365-29217-5-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>