Arnaldo Carvalho de Melo 899e5ffbf2 perf record: Introduce --switch-output-event ... Now we can use it with --overwrite to have a flight recorder mode that gets snapshot requests from arbitrary events that are processed in the side band thread together with the PERF_RECORD_BPF_EVENT processing. Example: To collect scheduler events until a recvmmsg syscall happens, system wide: [root@five a]# rm -f perf.data.2020042717* [root@five a]# perf record --overwrite -e sched:*switch,syscalls:*recvmmsg --switch-output-event syscalls:sys_enter_recvmmsg [ perf record: dump data: Woken up 1 times ] [ perf record: Dump perf.data.2020042717585458 ] [ perf record: dump data: Woken up 1 times ] [ perf record: Dump perf.data.2020042717590235 ] [ perf record: dump data: Woken up 1 times ] [ perf record: Dump perf.data.2020042717590398 ] ^C[ perf record: Woken up 1 times to write data ] [ perf record: Dump perf.data.2020042717590511 ] [ perf record: Captured and wrote 7.244 MB perf.data.<timestamp> ] So in the above case we had 3 snapshots, the fourth was forced by control+C: [root@five a]# ls -la total 20440 drwxr-xr-x. 2 root root 4096 Apr 27 17:59 . dr-xr-x---. 12 root root 4096 Apr 27 17:46 .. -rw-------. 1 root root 3936125 Apr 27 17:58 perf.data.2020042717585458 -rw-------. 1 root root 5074869 Apr 27 17:59 perf.data.2020042717590235 -rw-------. 1 root root 4291037 Apr 27 17:59 perf.data.2020042717590398 -rw-------. 1 root root 7617037 Apr 27 17:59 perf.data.2020042717590511 [root@five a]# One can make this more precise by adding the switch output event to the main -e events list, as since this is done asynchronously, a few events after the signal event will appear in the snapshots, as can be seen with: [root@five a]# rm -f perf.data.20200427175* [root@five a]# perf record --overwrite -e sched:*switch,syscalls:*recvmmsg --switch-output-event syscalls:sys_enter_recvmmsg [ perf record: dump data: Woken up 1 times ] [ perf record: Dump perf.data.2020042718024203 ] [ perf record: dump data: Woken up 1 times ] [ perf record: Dump perf.data.2020042718024301 ] [ perf record: dump data: Woken up 1 times ] [ perf record: Dump perf.data.2020042718024484 ] ^C[ perf record: Woken up 1 times to write data ] [ perf record: Dump perf.data.2020042718024562 ] [ perf record: Captured and wrote 7.337 MB perf.data.<timestamp> ] [root@five a]# perf script -i perf.data.2020042718024203 | tail -15 PacerThread 148586 [005] 122.830729: sched:sched_switch: prev_comm=PacerThread prev_pid=148586... swapper 0 [000] 122.833588: sched:sched_switch: prev_comm=swapper/0 prev_pid=... NetworkManager 1251 [000] 122.833619: syscalls:sys_enter_recvmmsg: fd: 0x0000001c, mmsg: 0x7ffe83054a1... swapper 0 [002] 122.833624: sched:sched_switch: prev_comm=swapper/2 prev_pid=... swapper 0 [003] 122.833624: sched:sched_switch: prev_comm=swapper/3 prev_pid=... NetworkManager 1251 [000] 122.833626: syscalls:sys_exit_recvmmsg: 0x1 kworker/3:3-eve 158946 [003] 122.833628: sched:sched_switch: prev_comm=kworker/3:3 prev_pid=15894... swapper 0 [004] 122.833641: sched:sched_switch: prev_comm=swapper/4 prev_pid=... NetworkManager 1251 [000] 122.833642: sched:sched_switch: prev_comm=NetworkManage... perf 228273 [002] 122.833645: sched:sched_switch: prev_comm=perf prev_pid=22827... swapper 0 [011] 122.833646: sched:sched_switch: prev_comm=swapper/1... swapper 0 [002] 122.833648: sched:sched_switch: prev_comm=swapper/... kworker/0:2-eve 207387 [000] 122.833648: sched:sched_switch: prev_comm=kworker/0:2 prev_pid=20738... kworker/2:3-eve 232038 [002] 122.833652: sched:sched_switch: prev_comm=kworker/2:3 prev_pid=23203... perf 235825 [003] 122.833653: sched:sched_switch: prev_comm=perf prev_pid=23582... [root@five a]# Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lore.kernel.org/lkml/20200429131106.27974-8-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>		2020-05-05 16:35:29 -03:00
..
Build.txt	perf tools: Add doc about how to build perf with Asan and UBSan	2019-03-19 16:52:04 -03:00
Makefile	perf doc: allow ASCIIDOC_EXTRA to be an argument	2020-04-18 09:05:00 -03:00
android.txt	perf tools: Update android build documentation	2016-07-04 20:27:27 -03:00
asciidoc.conf	perf docs: Allow man page date to be specified	2019-09-27 09:26:14 -03:00
asciidoctor-extensions.rb	perf Documentation: Support for asciidoctor	2018-04-26 13:47:10 -03:00
build-xed.txt	perf script: Add --insn-trace for instruction decoding	2018-10-24 15:29:50 -03:00
callchain-overhead-calculation.txt	perf tools: Document --children option in more detail	2015-04-29 10:38:06 -03:00
db-export.txt	perf db-export: Add brief documentation	2019-06-05 09:47:57 -03:00
examples.txt	perf record: Remove -f/--force option	2013-07-08 17:37:25 -03:00
intel-bts.txt	perf tools: Add Intel BTS support	2015-08-21 11:34:10 -03:00
intel-pt.txt	perf intel-pt: Update intel-pt.txt file with new location of the documentation	2020-03-11 11:00:33 -03:00
itrace.txt	perf auxtrace: Add an option to synthesize callchains for regular events	2020-04-16 12:19:15 -03:00
jit-interface.txt	perf symbols: Add description of JIT interface	2012-08-13 14:55:02 -03:00
jitdump-specification.txt	perf docs: Correct and clarify jitdump spec	2019-09-30 17:29:51 -03:00
manpage-1.72.xsl	…
manpage-base.xsl	…
manpage-bold-literal.xsl	…
manpage-normal.xsl	…
manpage-suppress-sp.xsl	…
perf-annotate.txt	perf tools: Support --prefix/--prefix-strip	2020-01-14 12:02:19 -03:00
perf-archive.txt	perf archive: Remove duplicated 'runs' in man page	2013-12-09 15:21:45 -03:00
perf-bench.txt	perf bench: Add event synthesis benchmark	2020-04-16 12:19:12 -03:00
perf-buildid-cache.txt	perf buildid-cache: Support --purge-all option	2018-04-26 09:30:26 -03:00
perf-buildid-list.txt	perf report: Accept fifos as input file	2011-12-23 17:01:03 -02:00
perf-c2c.txt	perf c2c: Add option to enable the LBR stitching approach	2020-04-18 09:05:01 -03:00
perf-config.txt	perf callchain: Update docs regarding kernel/user space unwinding	2020-03-25 16:13:21 -03:00
perf-data.txt	perf tools: Correct title markers for asciidoctor	2018-03-07 10:26:32 -03:00
perf-diff.txt	perf diff: Report noisy for cycles diff	2019-10-11 10:57:00 -03:00
perf-evlist.txt	perf evlist: Document missing --force option	2017-11-16 14:50:07 -03:00
perf-ftrace.txt	perf tools: Correct title markers for asciidoctor	2018-03-07 10:26:32 -03:00
perf-help.txt	…
perf-inject.txt	perf intel-pt: Add Intel PT man page references	2020-03-11 11:00:09 -03:00
perf-intel-pt.txt	perf intel-pt: Add Intel PT man page references	2020-03-11 11:00:09 -03:00
perf-kallsyms.txt	perf tools: Correct title markers for asciidoctor	2018-03-07 10:26:32 -03:00
perf-kmem.txt	perf kmem: Document a missing option & an argument	2018-02-16 14:55:42 -03:00
perf-kvm.txt	perf kvm: Clarify the 'perf kvm' -i and -o command line options	2019-12-02 15:38:59 -03:00
perf-list.txt	perf parser: Add support to specify rXXX event with pmu	2020-04-18 09:05:00 -03:00
perf-lock.txt	perf lock: Document missing options	2017-11-16 14:50:04 -03:00
perf-mem.txt	perf mem/c2c: Fix perf_mem_events to support powerpc	2019-02-04 11:32:14 -03:00
perf-probe.txt	perf-probe: Add user memory access attribute support	2019-05-25 23:04:42 -04:00
perf-record.txt	perf record: Introduce --switch-output-event	2020-05-05 16:35:29 -03:00
perf-report.txt	perf report: Add option to enable the LBR stitching approach	2020-04-18 09:05:01 -03:00
perf-sched.txt	perf sched timehist: Add support for filtering on CPU	2020-01-06 11:46:09 -03:00
perf-script-perl.txt	perf tools: Correct title markers for asciidoctor	2018-03-07 10:26:32 -03:00
perf-script-python.txt	perf script python: Add dict fields introduction to Documentation	2018-06-06 15:40:10 -03:00
perf-script.txt	perf script: Add option to enable the LBR stitching approach	2020-04-18 09:05:01 -03:00
perf-stat.txt	perf stat: Improve runtime stat for interval mode	2020-04-23 11:03:46 -03:00
perf-test.txt	perf test: Add -F/--dont-fork option	2016-06-30 18:27:45 -03:00
perf-timechart.txt	perf timechart: Document missing --force option	2017-11-16 14:50:06 -03:00
perf-top.txt	perf top: Add option to enable the LBR stitching approach	2020-04-18 09:05:01 -03:00
perf-trace.txt	perf trace: Introduce --errno-summary	2019-10-15 13:03:49 -03:00
perf-version.txt	perf version: Add man page	2018-04-02 13:52:23 -03:00
perf.data-directory-format.txt	perf record: Put a copy of kcore into the perf.data directory	2019-11-06 15:43:05 -03:00
perf.data-file-format.txt	perf header: Support CPU PMU capabilities	2020-04-18 09:05:00 -03:00
perf.txt	perf tool: Provide an option to print perf_event_open args and return value	2019-11-12 08:32:27 -03:00
perfconfig.example	perf config: Show default report configuration in example and docs	2016-09-01 09:44:13 -03:00
tips.txt	perf tools: Fix typos / broken sentences	2019-07-02 16:08:16 -03:00