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perf stat: Fix compatibility behavior 

Instead of failing on an unknown event, when new perf stat is run on
older kernels:

  $ ./perf stat true
  Error: open_counter returned with 22 (Invalid argument). /bin/dmesg
  may provide additional information.

  Fatal: Not all events could be opened.

Just ignore EINVAL and ENOSYS, we'll print the results as not counted:

 Performance counter stats for 'true':

          0.239483 task-clock               #    0.493 CPUs utilized
                 0 context-switches         #    0.000 M/sec
                 0 CPU-migrations           #    0.000 M/sec
                86 page-faults              #    0.359 M/sec
           704,766 cycles                   #    2.943 GHz
     <not counted> stalled-cycles
           381,961 instructions             #    0.54  insns per cycle
            69,626 branches                 #  290.735 M/sec
             4,594 branch-misses            #    6.60% of all branches

        0.000485883  seconds time elapsed

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/n/tip-7y40wib8n1eqio5hjpn3dsrm@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar 2011-04-28 08:48:42 +02:00
parent f9cef0a90c
commit ede7029004
1 changed files with 4 additions and 1 deletions
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5
tools/perf/builtin-stat.c
View File

@ -372,7 +372,10 @@ 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 == -EPERM || errno == -EACCES) {
if (errno == EINVAL || errno == ENOSYS)
continue;
if (errno == EPERM || errno == EACCES) {
error("You may not have permission to collect %sstats.\n"
"\t Consider tweaking"
" /proc/sys/kernel/perf_event_paranoid or running as root.",