leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

perf evsel: State in the default event name if attr.exclude_kernel is set

Browse Source 
When no event is specified perf will use the "cycles" hardware event
with the highest precision available in the processor, and excluding
kernel events for non-root users, so make that clear in the event name
by setting the "u" event modifier, i.e. "cycles:upp".

E.g.:

The default for root:

  # perf record usleep 1
  # perf evlist -v
  cycles:ppp: ..., precise_ip: 3, exclude_kernel: 0, ...
  #

And for !root:

  $ perf record usleep 1
  $ perf evlist -v
  cycles:uppp: ... , precise_ip: 3, exclude_kernel: 1, ...
  $

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-lf29zcdl422i9knrgde0uwy3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2017-07-10 16:19:25 -03:00
parent d37a369790
commit ede5626d30
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
tools/perf/util/evsel.c
View File

@ -298,8 +298,10 @@ struct perf_evsel *perf_evsel__new_cycles(void)
goto out;
/* use asprintf() because free(evsel) assumes name is allocated */
if (asprintf(&evsel->name, "cycles%.*s",
attr.precise_ip ? attr.precise_ip + 1 : 0, ":ppp") < 0)
if (asprintf(&evsel->name, "cycles%s%s%.*s",
(attr.precise_ip || attr.exclude_kernel) ? ":" : "",
attr.exclude_kernel ? "u" : "",
attr.precise_ip ? attr.precise_ip + 1 : 0, "ppp") < 0)
goto error_free;
out:
return evsel;