[tip:perf/stat] perf stat: Tell user about unsupported events in the list

[tip-bot for David Ahern <dsahern@gmail.com>]

Commit-ID:  c63ca0c01d73563d4e2ab174bb3dd1e5efb907e6
Gitweb:     http://git.kernel.org/tip/c63ca0c01d73563d4e2ab174bb3dd1e5efb907e6
Author:     David Ahern <dsahern@gmail.com>
AuthorDate: Fri, 29 Apr 2011 16:04:15 -0600
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Sat, 30 Apr 2011 00:18:14 +0200

perf stat: Tell user about unsupported events in the list

Similar to perf-record, tell user about unsupported events
that will not be counted if invoked in verbose mode.

e.g.,

 $ perf stat -e dTLB-prefetch-misses -v -- sleep 1
 dTLB-prefetch-misses event is not supported by the kernel.
 dTLB-prefetch-misses: 0 0 0

 Performance counter stats for 'sleep 1':

     <not counted> dTLB-prefetch-misses

        1.001884783  seconds time elapsed

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1304114655-10600-1-git-send-email-dsahern@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 tools/perf/builtin-stat.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index c8b535b..602c3c9 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -377,8 +377,12 @@ static int run_perf_stat(int argc __used, const char **argv)
 
 	list_for_each_entry(counter, &evsel_list->entries, node) {
 		if (create_perf_stat_counter(counter) < 0) {
-			if (errno == EINVAL || errno == ENOSYS || errno == ENOENT)
+			if (errno == EINVAL || errno == ENOSYS || errno == ENOENT) {
+				if (verbose)
+					ui__warning("%s event is not supported by the kernel.\n",
+						    event_name(counter));
 				continue;
+			}
 
 			if (errno == EPERM || errno == EACCES) {
 				error("You may not have permission to collect %sstats.\n"