perf_counter: Provide a way to enable counters on exec

This provides a way to mark a counter to be enabled on the next
exec. This is useful for measuring the total activity of a
program without including overhead from the process that
launches it.

This also changes the perf stat command to use this new
facility.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <19017.43927.838745.689203@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index 3078e23c91eb..5e970c7d3fd5 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -179,8 +179,9 @@ struct perf_counter_attr {
                                 comm           :  1, /* include comm data     */
                                 freq           :  1, /* use freq, not period  */
                                 inherit_stat   :  1, /* per task counts       */
+                                enable_on_exec :  1, /* next exec enables     */
 
-                                __reserved_1   : 52;
+                                __reserved_1   : 51;
 
         __u32                   wakeup_events;  /* wakeup every n events */
         __u32                   __reserved_2;