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| author |   Arnaldo Carvalho de Melo <acme@redhat.com> | 2018-12-14 11:06:16 -0300 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2018-12-18 12:24:01 -0300 |
| commit | d32de87e734191698dd1834146ee65ebd0f5e240 (patch) | |
| tree | 0c739f306eab7871c7bc1575a69709625d996123 /tools/perf | |
| parent | perf config: Show the configuration when no arguments are provided (diff) | |
| download | wireguard-linux-d32de87e734191698dd1834146ee65ebd0f5e240.tar.xz wireguard-linux-d32de87e734191698dd1834146ee65ebd0f5e240.zip | |
perf trace: Allow configuring default for perf_event_attr.inherit
I.f. if children should inherit the parent perf_event configuration,
i.e. if we should trace children as well or just the parent.
The default is to follow children, to disable this and have a behaviour
similar to strace, set this config option or use the --no_inherit 'perf
trace' option.
E.g.:
Default:
# perf config trace.no_inherit
# trace -e clone,*sleep time sleep 1
0.000 time/21107 clone(clone_flags: CHILD_CLEARTID|CHILD_SETTID|0x11, newsp: 0, child_tidptr: 0x7f7b8f9ae810) = 21108 (time)
? time/21108 ... [continued]: clone()
0.691 sleep/21108 nanosleep(rqtp: 0x7ffed01d0540, rmtp: 0 ) = 0
0.00user 0.00system 0:01.00elapsed 0%CPU (0avgtext+0avgdata 1988maxresident)k
0inputs+0outputs (0major+76minor)pagefaults 0swaps
#
Disable it:
# trace -e clone,*sleep time sleep 1
0.000 clone(clone_flags: CHILD_CLEARTID|CHILD_SETTID|0x11, newsp: 0, child_tidptr: 0x7ff41e100810) = 21414 (time)
0.00user 0.00system 0:01.00elapsed 0%CPU (0avgtext+0avgdata 1964maxresident)k
0inputs+0outputs (0major+76minor)pagefaults 0swaps
#
Notice that since there is just one thread, the "comm/TID" column is
suppressed.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-thd8s16pagyza71ufi5vjlan@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf')
| -rw-r--r-- | tools/perf/Documentation/perf-config.txt | 3 | ||||
| -rw-r--r-- | tools/perf/builtin-trace.c | 2 |
2 files changed, 5 insertions, 0 deletions
diff --git a/tools/perf/Documentation/perf-config.txt b/tools/perf/Documentation/perf-config.txt index 0d641b0d15ae..cd9bf12fb255 100644 --- a/tools/perf/Documentation/perf-config.txt +++ b/tools/perf/Documentation/perf-config.txt @@ -529,6 +529,9 @@ trace.*:: activate the 'perf trace' logic that looks for syscall pointer contents after the normal tracepoint payload. + trace.no_inherit:: + Do not follow children threads. + trace.show_duration:: Show syscall duration. diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 4355dadad232..a4e2290e57e0 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -3542,6 +3542,8 @@ static int trace__config(const char *var, const char *value, void *arg) trace->show_duration = perf_config_bool(var, value); } else if (!strcmp(var, "trace.show_zeros")) { trace->show_zeros = perf_config_bool(var, value); + } else if (!strcmp(var, "trace.no_inherit")) { + trace->opts.no_inherit = perf_config_bool(var, value); } return err; |