perf tools: Add perf_event_paranoid()

Add a function to return the value of
/proc/sys/kernel/perf_event_paranoid.

This will be used to determine default values for mmap size because perf
is not subject to mmap limits when perf_event_paranoid is less than
zero.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1386765443-26966-12-git-send-email-alexander.shishkin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Adrian Hunter
2013-12-11 14:36:23 +02:00
committed by Arnaldo Carvalho de Melo
parent c506c96b61
commit 1a47245d2f
3 changed files with 21 additions and 2 deletions

View File

@@ -1191,8 +1191,7 @@ int perf_evlist__strerror_open(struct perf_evlist *evlist __maybe_unused,
"Error:\t%s.\n"
"Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.", emsg);
if (filename__read_int("/proc/sys/kernel/perf_event_paranoid", &value))
break;
value = perf_event_paranoid();
printed += scnprintf(buf + printed, size - printed, "\nHint:\t");