[PATCH 2/2] perf record: Mention paranoid sysctl when failing to create counter

[Arnaldo Carvalho de Melo]

From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

[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@xxxxxxx>
Cc: FrÃdÃric Weisbecker <fweisbec@xxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/builtin-record.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 3bf1409..b280ab5 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -283,7 +283,8 @@ 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");
 
-- 
1.5.5.1

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