diff options
| author | Adrian Hunter <adrian.hunter@intel.com> | 2013-12-11 14:36:23 +0200 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2013-12-13 10:30:20 -0300 |
| commit | 1a47245d2f3bf6276c95cd37901b562962d6ae47 (patch) | |
| tree | 0df8a19d1170beaea788b629c7cff52201a80cae | |
| parent | c506c96b61fa96c9a52ad4d25e895e45c1692650 (diff) | |
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>
| -rw-r--r-- | tools/perf/util/evlist.c | 3 | ||||
| -rw-r--r-- | tools/perf/util/util.c | 19 | ||||
| -rw-r--r-- | tools/perf/util/util.h | 1 |
3 files changed, 21 insertions, 2 deletions
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index af250556b33..2eb7378e4c4 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -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"); diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c index 4a57609c0b4..8f63dba212d 100644 --- a/tools/perf/util/util.c +++ b/tools/perf/util/util.c @@ -1,5 +1,6 @@ #include "../perf.h" #include "util.h" +#include "fs.h" #include <sys/mman.h> #ifdef HAVE_BACKTRACE_SUPPORT #include <execinfo.h> @@ -8,6 +9,7 @@ #include <stdlib.h> #include <string.h> #include <errno.h> +#include <limits.h> #include <linux/kernel.h> /* @@ -496,3 +498,20 @@ const char *get_filename_for_perf_kvm(void) return filename; } + +int perf_event_paranoid(void) +{ + char path[PATH_MAX]; + const char *procfs = procfs__mountpoint(); + int value; + + if (!procfs) + return INT_MAX; + + scnprintf(path, PATH_MAX, "%s/sys/kernel/perf_event_paranoid", procfs); + + if (filename__read_int(path, &value)) + return INT_MAX; + + return value; +} diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h index 0171213d1d4..1e7d4136cc8 100644 --- a/tools/perf/util/util.h +++ b/tools/perf/util/util.h @@ -321,6 +321,7 @@ void free_srcline(char *srcline); int filename__read_int(const char *filename, int *value); int filename__read_str(const char *filename, char **buf, size_t *sizep); +int perf_event_paranoid(void); const char *get_filename_for_perf_kvm(void); #endif /* GIT_COMPAT_UTIL_H */ |