From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751909Ab3LKMip (ORCPT ); Wed, 11 Dec 2013 07:38:45 -0500 Received: from mga09.intel.com ([134.134.136.24]:32257 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751527Ab3LKMil (ORCPT ); Wed, 11 Dec 2013 07:38:41 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.93,871,1378882800"; d="scan'208";a="442368176" From: Alexander Shishkin To: Peter Zijlstra , Arnaldo Carvalho de Melo Cc: Ingo Molnar , linux-kernel@vger.kernel.org, David Ahern , Frederic Weisbecker , Jiri Olsa , Mike Galbraith , Namhyung Kim , Paul Mackerras , Stephane Eranian , Andi Kleen , Adrian Hunter Subject: [PATCH v0 11/71] perf tools: Add perf_event_paranoid() Date: Wed, 11 Dec 2013 14:36:23 +0200 Message-Id: <1386765443-26966-12-git-send-email-alexander.shishkin@linux.intel.com> X-Mailer: git-send-email 1.8.4.rc2 In-Reply-To: <1386765443-26966-1-git-send-email-alexander.shishkin@linux.intel.com> References: <1386765443-26966-1-git-send-email-alexander.shishkin@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Adrian Hunter 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 --- tools/perf/util/evlist.c | 3 +-- tools/perf/util/util.c | 19 +++++++++++++++++++ tools/perf/util/util.h | 3 +++ 3 files changed, 23 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 7bb6ee1..50fadde 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1189,8 +1189,7 @@ 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 bae8756..3aed4af 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 #ifdef HAVE_BACKTRACE_SUPPORT #include @@ -8,6 +9,7 @@ #include #include #include +#include #include /* @@ -482,3 +484,20 @@ int filename__read_str(const char *filename, char **buf, size_t *sizep) close(fd); return err; } + +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 adb39f2..4b6b260 100644 --- a/tools/perf/util/util.h +++ b/tools/perf/util/util.h @@ -309,4 +309,7 @@ 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); + #endif /* GIT_COMPAT_UTIL_H */ -- 1.8.5.1