From: tip-bot for Arnaldo Carvalho de Melo <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: acme@redhat.com, wangnan0@huawei.com, mingo@kernel.org,
linux-kernel@vger.kernel.org, adrian.hunter@intel.com,
tglx@linutronix.de, jolsa@kernel.org, hpa@zytor.com,
namhyung@kernel.org, dsahern@gmail.com
Subject: [tip:perf/core] perf evsel: Inform how to make a sysctl setting permanent
Date: Mon, 13 Feb 2017 22:41:40 -0800 [thread overview]
Message-ID: <tip-4gwe99k4a6p12d4u8bbyttj2@git.kernel.org> (raw)
Commit-ID: d6195a6a2c247515d5832debb51c03a74dc3f8f6
Gitweb: http://git.kernel.org/tip/d6195a6a2c247515d5832debb51c03a74dc3f8f6
Author: Arnaldo Carvalho de Melo <acme@redhat.com>
AuthorDate: Mon, 13 Feb 2017 16:45:24 -0300
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Mon, 13 Feb 2017 17:22:33 -0300
perf evsel: Inform how to make a sysctl setting permanent
When a tool can't open counters due to the kernel.perf_event_paranoit
sysctl setting, we inform how to tweak it to allow the operation to
succeed, in addition to that, suggest setting /etc/sysctl.conf to
make the setting permanent.
Suggested-by: Ingo Molnar <mingo@kernel.org>
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-4gwe99k4a6p12d4u8bbyttj2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-record.c | 2 +-
tools/perf/builtin-stat.c | 2 +-
tools/perf/builtin-top.c | 2 +-
tools/perf/util/evsel.c | 4 +++-
4 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index ffac8ca..2ddf189 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -418,7 +418,7 @@ static int record__mmap(struct record *rec)
static int record__open(struct record *rec)
{
- char msg[512];
+ char msg[BUFSIZ];
struct perf_evsel *pos;
struct perf_evlist *evlist = rec->evlist;
struct perf_session *session = rec->session;
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index a02f2e9..f287191 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -533,7 +533,7 @@ static int store_counter_ids(struct perf_evsel *counter)
static int __run_perf_stat(int argc, const char **argv)
{
int interval = stat_config.interval;
- char msg[512];
+ char msg[BUFSIZ];
unsigned long long t0, t1;
struct perf_evsel *counter;
struct timespec ts;
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index d90927f..5a7fd7a 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -859,7 +859,7 @@ static void perf_top__mmap_read(struct perf_top *top)
static int perf_top__start_counters(struct perf_top *top)
{
- char msg[512];
+ char msg[BUFSIZ];
struct perf_evsel *counter;
struct perf_evlist *evlist = top->evlist;
struct record_opts *opts = &top->record_opts;
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 04e536a..cd2fb42 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -2469,7 +2469,9 @@ int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
" -1: Allow use of (almost) all events by all users\n"
">= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK\n"
">= 1: Disallow CPU event access by users without CAP_SYS_ADMIN\n"
- ">= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN",
+ ">= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN\n\n"
+ "To make this setting permanent, edit /etc/sysctl.conf too, e.g.:\n\n"
+ " kernel.perf_event_paranoid = -1\n" ,
target->system_wide ? "system-wide " : "",
perf_event_paranoid());
case ENOENT:
reply other threads:[~2017-02-14 6:42 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=tip-4gwe99k4a6p12d4u8bbyttj2@git.kernel.org \
--to=tipbot@zytor.com \
--cc=acme@redhat.com \
--cc=adrian.hunter@intel.com \
--cc=dsahern@gmail.com \
--cc=hpa@zytor.com \
--cc=jolsa@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=namhyung@kernel.org \
--cc=tglx@linutronix.de \
--cc=wangnan0@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox