lkml.org 
[lkml]   [2015]   [Feb]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCHv2] perf/stat: Report unsupported events properly
On 13/02/15 20:50, Arnaldo Carvalho de Melo wrote:
> Em Fri, Feb 13, 2015 at 12:39:24PM -0700, David Ahern escreveu:
>>
>>
>> On 02/13/2015 11:40 AM, Suzuki K. Poulose wrote:
>>> From: "Suzuki K. Poulose" <suzuki.poulose@arm.com>
>>>
>>> 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.
>>>
>>> Cc: Jiri Olsa <jolsa@kernel.org>
>>> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
>>> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
>>> ---
>>> tools/perf/builtin-stat.c | 5 ++++-
>>> 1 file changed, 4 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
>>> index e598e4e..d28949d 100644
>>> --- a/tools/perf/builtin-stat.c
>>> +++ b/tools/perf/builtin-stat.c
>>> @@ -510,6 +510,9 @@ static int read_counter(struct perf_evsel *counter)
>>> int ncpus = perf_evsel__nr_cpus(counter);
>>> int cpu, thread;
>>>
>>> + if (!counter->supported)
>>> + return -ENOENT;
>>> +
>>> if (counter->system_wide)
>>> nthreads = 1;
>>>
>>> @@ -1285,7 +1288,7 @@ static void print_counter_aggr(struct perf_evsel *counter, char *prefix)
>>> if (prefix)
>>> fprintf(output, "%s", prefix);
>>>
>>> - if (scaled == -1) {
>>> + if (scaled == -1 || !counter->supported) {
>>> fprintf(output, "%*s%s",
>>> csv_output ? 0 : 18,
>>> counter->supported ? CNTR_NOT_COUNTED : CNTR_NOT_SUPPORTED,
>>>
>>
>> Just hit this as well.
>>
>> Acked-and-Tested-by: David Ahern <dsahern@gmail.com>
>
> Gack, 10ms after I sent my pre-California pull req :-\
>
> Will go in the next one :-)
I think this may need to goto 3.19 stable series as well. Missed that.
Do you want me to send it there ?

Cheers
Suzuki




\
 
 \ /
  Last update: 2015-02-17 11:21    [W:0.190 / U:0.932 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site