From 5229e366ee6baeb58b77e09643d2e11cbbd29950 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 10 Jun 2014 17:18:54 -0300 Subject: [PATCH] perf evlist: Add suggestion of how to set perf_event_paranoid sysctl Minor hint to speed up problem resolution and get 'trace' working for non root users. Cc: Adrian Hunter Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Mike Galbraith Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-abdqi8km4fj9osrn70q2zj9v@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/evlist.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 59ef2802fcf6..c51223ac25f4 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1214,10 +1214,11 @@ int perf_evlist__strerror_open(struct perf_evlist *evlist __maybe_unused, "For your workloads it needs to be <= 1\nHint:\t"); } printed += scnprintf(buf + printed, size - printed, - "For system wide tracing it needs to be set to -1"); + "For system wide tracing it needs to be set to -1.\n"); printed += scnprintf(buf + printed, size - printed, - ".\nHint:\tThe current value is %d.", value); + "Hint:\tTry: 'sudo sh -c \"echo -1 > /proc/sys/kernel/perf_event_paranoid\"'\n" + "Hint:\tThe current value is %d.", value); break; default: scnprintf(buf, size, "%s", emsg);