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 <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120920161945.GA7064@quad
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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 @@
}
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 &&
