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| author |  Adrian Hunter <adrian.hunter@intel.com>
| 2020-09-01 12:37:57 +0300 |
|---|---|---|
| committer |  Arnaldo Carvalho de Melo <acme@redhat.com>
| 2020-09-04 14:38:15 -0300 |
| commit | d20aff1512f013fab79b8740427b7574569a9a2e (patch) | |
| tree | 43c5261c26024130049b82902d24a0972baca09d /tools/perf/Documentation/perf-record.txt | |
| parent | perf tools: Add FIFO file names as alternative options to --control (diff) | |
| download | linux-d20aff1512f013fab79b8740427b7574569a9a2e.tar.gz linux-d20aff1512f013fab79b8740427b7574569a9a2e.tar.bz2 linux-d20aff1512f013fab79b8740427b7574569a9a2e.zip | |
perf record: Add 'snapshot' control command
Add 'snapshot' control command to create an AUX area tracing snapshot
the same as if sending SIGUSR2. The advantage of the FIFO is that access
is governed by access to the FIFO.
Example:
$ mkfifo perf.control
$ mkfifo perf.ack
$ cat perf.ack &
[1] 15235
$ sudo ~/bin/perf record --control fifo:perf.control,perf.ack -S -e intel_pt//u -- sleep 60 &
[2] 15243
$ ps -e | grep perf
15244 pts/1 00:00:00 perf
$ kill -USR2 15244
bash: kill: (15244) - Operation not permitted
$ echo snapshot > perf.control
ack
$
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200901093758.32293-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/Documentation/perf-record.txt')
| -rw-r--r-- | tools/perf/Documentation/perf-record.txt | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index c1f44633abed..768888b9326a 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -635,10 +635,10 @@ endif::HAVE_LIBPFM[] --control=fd:ctl-fd[,ack-fd]:: ctl-fifo / ack-fifo are opened and used as ctl-fd / ack-fd as follows. Listen on ctl-fd descriptor for command to control measurement ('enable': enable events, -'disable': disable events). Measurements can be started with events disabled using ---delay=-1 option. Optionally send control command completion ('ack\n') to ack-fd descriptor -to synchronize with the controlling process. Example of bash shell script to enable and -disable events during measurements: +'disable': disable events, 'snapshot': AUX area tracing snapshot). Measurements can be +started with events disabled using --delay=-1 option. Optionally send control command +completion ('ack\n') to ack-fd descriptor to synchronize with the controlling process. +Example of bash shell script to enable and disable events during measurements: #!/bin/bash |