Commit 1971f59 (perf stat: Use read_counter in read_counter_aggr )
broke the perf stat output for unsupported counters.
$ perf stat -v -a -C 0 -e CCI_400/config=24/ sleep 1
Warning:
CCI_400/config=24/ event is not supported by the kernel.
Performance counter stats for 'system wide':
0 CCI_400/config=24/
1.080265400 seconds time elapsed
Where it used to be :
$ perf stat -v -a -C 0 -e CCI_400/config=24/ sleep 1
Warning:
CCI_400/config=24/ event is not supported by the kernel.
Performance counter stats for 'system wide':
<not supported> CCI_400/config=24/
1.083840675 seconds time elapsed
This patch fixes the issues by checking if the counter is supported,
before reading and logging the counter value.
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1423852858-8455-1-git-send-email-suzuki.poulose@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
3b4331d9a4