path: root/tools/perf/builtin-record.c
diff options
authorArnaldo Carvalho de Melo <acme@redhat.com>2010-03-11 15:53:12 -0300
committerIngo Molnar <mingo@elte.hu>2010-03-11 20:00:48 +0100
commit6230f2c7ef01a69e2ba9370326572c287209d32a (patch)
treeec8c42151dd9a7d280c220d5a0752b2aabf7d538 /tools/perf/builtin-record.c
parent9b33fa6ba0e2f90fdf407501db801c2511121564 (diff)
perf record: Mention paranoid sysctl when failing to create counter
[acme@mica linux-2.6-tip]$ perf record -a -f Fatal: Permission error - are you root? Consider tweaking /proc/sys/kernel/perf_event_paranoid. [acme@mica linux-2.6-tip]$ Suggested-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1268333592-30872-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'tools/perf/builtin-record.c')
1 files changed, 2 insertions, 1 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 771533ced6a..6e4a39328b3 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -280,7 +280,8 @@ try_again:
int err = errno;
if (err == EPERM || err == EACCES)
- die("Permission error - are you root?\n");
+ die("Permission error - are you root?\n"
+ "\t Consider tweaking /proc/sys/kernel/perf_event_paranoid.\n");
else if (err == ENODEV && profile_cpu != -1)
die("No such device - did you specify an out-of-range profile CPU?\n");