From: Arnaldo Carvalho de Melo Date: Thu, 11 Mar 2010 18:53:12 +0000 (-0300) Subject: perf record: Mention paranoid sysctl when failing to create counter X-Git-Tag: firefly_0821_release~9833^2~1617^2~259 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6230f2c7ef01a69e2ba9370326572c287209d32a;p=firefly-linux-kernel-4.4.55.git 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 Signed-off-by: Arnaldo Carvalho de Melo Cc: Frédéric Weisbecker Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Paul Mackerras LKML-Reference: <1268333592-30872-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar --- diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 771533ced6a8..6e4a39328b33 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");