From: Adrian Hunter <[email protected]> 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 <[email protected]> Cc: Andi Kleen <[email protected]> Cc: David Ahern <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lkml.kernel.org/r/1386765443-26966-12-git-send-email-alexander.shish...@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/util/evlist.c | 3 +-- tools/perf/util/util.c | 19 +++++++++++++++++++ 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 af250556b33f..2eb7378e4c40 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 4a57609c0b43..8f63dba212d7 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 0171213d1d4d..1e7d4136cc82 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 */ -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
