From 1863fbbb781b1129da0cfdad46ef875370a34117 Mon Sep 17 00:00:00 2001 From: Stephane Eranian Date: Thu, 20 Sep 2012 18:19:45 +0200 Subject: [PATCH] perf record: Print event causing perf_event_open() to fail Got tired of not getting the event that caused the perf_event_open() syscall to fail. So I fixed the error message. This is very useful when monitoring lots of events in a single run. Signed-off-by: Stephane Eranian Cc: David Ahern Cc: Ingo Molnar Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20120920161945.GA7064@quad Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-record.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index c643ed6..2cb7434 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -297,8 +297,10 @@ try_again: } printf("\n"); - error("sys_perf_event_open() syscall returned with %d (%s). /bin/dmesg may provide additional information.\n", - err, strerror(err)); + error("sys_perf_event_open() syscall returned with %d " + "(%s) for event %s. /bin/dmesg may provide " + "additional information.\n", + err, strerror(err), perf_evsel__name(pos)); #if defined(__i386__) || defined(__x86_64__) if (attr->type == PERF_TYPE_HARDWARE && -- 2.7.4