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Subject[tip:perf/urgent] perf record: Remove misleading error suggestion
Commit-ID:  ec3948451e0ba317e66873b48d6cc51d701d4eb0
Author: Andi Kleen <>
AuthorDate: Fri, 6 Apr 2018 13:38:11 -0700
Committer: Arnaldo Carvalho de Melo <>
CommitDate: Wed, 18 Apr 2018 15:35:49 -0300

perf record: Remove misleading error suggestion

When perf record encounters an error setting up an event it suggests
to enable CONFIG_PERF_EVENTS. This is misleading because:

- Usually it is enabled (it is really hard to disable on x86)

- The problem is usually somewhere else, e.g. the CPU is not supported
or an invalid configuration has been used.

Remove the misleading suggestion.

Signed-off-by: Andi Kleen <>
Acked-by: Jiri Olsa <>
Signed-off-by: Arnaldo Carvalho de Melo <>
tools/perf/util/evsel.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 1ac8d9236efd..66b62570c855 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -2894,8 +2894,7 @@ int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,

return scnprintf(msg, size,
"The sys_perf_event_open() syscall returned with %d (%s) for event (%s).\n"
- "/bin/dmesg may provide additional information.\n"
- "No CONFIG_PERF_EVENTS=y kernel support configured?",
+ "/bin/dmesg | grep -i perf may provide additional information.\n",
err, str_error_r(err, sbuf, sizeof(sbuf)),
 \ /
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