diff options
author | Stephane Eranian <eranian@google.com> | 2010-08-26 10:40:01 -0400 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2010-08-30 06:16:55 -0400 |
commit | fa66f07aa1f0950e1dc78b7ab39728b3f8aa77a1 (patch) | |
tree | 4ad4612c2fc07f159e192fae9145f9d87a697592 /kernel/perf_event.c | |
parent | 5225c45899e872383ca39f5533d28ec63c54b39e (diff) |
perf_events: Fix time tracking for events with pid != -1 and cpu != -1
Per-thread events with a cpu filter, i.e., cpu != -1, were not
reporting correct timings when the thread never ran on the
monitored cpu. The time enabled was reported as a negative
value.
This patch fixes the problem by updating tstamp_stopped,
tstamp_running in event_sched_out() for events with filters and
which are marked as INACTIVE.
The function group_sched_out() is modified to systematically
call into event_sched_out() to avoid duplicating the timing
adjustment code twice.
With the patch, I now get:
$ task_cpu -i -e unhalted_core_cycles,unhalted_core_cycles
noploop 2 noploop for 2 seconds
CPU0 0 unhalted_core_cycles (ena=1,991,136,594, run=0)
CPU0 0 unhalted_core_cycles (ena=1,991,136,594, run=0)
CPU1 0 unhalted_core_cycles (ena=1,991,136,594, run=0)
CPU1 0 unhalted_core_cycles (ena=1,991,136,594, run=0)
CPU2 0 unhalted_core_cycles (ena=1,991,136,594, run=0)
CPU2 0 unhalted_core_cycles (ena=1,991,136,594, run=0)
CPU3 4,747,990,931 unhalted_core_cycles (ena=1,991,136,594, run=1,991,136,594)
CPU3 4,747,990,931 unhalted_core_cycles (ena=1,991,136,594, run=1,991,136,594)
Signed-off-by: Stephane Eranian <eranian@gmail.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org
Cc: davem@davemloft.net
Cc: fweisbec@gmail.com
Cc: perfmon2-devel@lists.sf.net
Cc: eranian@google.com
LKML-Reference: <4c76802d.aae9d80a.115d.70fe@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/perf_event.c')
-rw-r--r-- | kernel/perf_event.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 403d1804b198..657555a5f30f 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c | |||
@@ -402,11 +402,31 @@ static void perf_group_detach(struct perf_event *event) | |||
402 | } | 402 | } |
403 | } | 403 | } |
404 | 404 | ||
405 | static inline int | ||
406 | event_filter_match(struct perf_event *event) | ||
407 | { | ||
408 | return event->cpu == -1 || event->cpu == smp_processor_id(); | ||
409 | } | ||
410 | |||
405 | static void | 411 | static void |
406 | event_sched_out(struct perf_event *event, | 412 | event_sched_out(struct perf_event *event, |
407 | struct perf_cpu_context *cpuctx, | 413 | struct perf_cpu_context *cpuctx, |
408 | struct perf_event_context *ctx) | 414 | struct perf_event_context *ctx) |
409 | { | 415 | { |
416 | u64 delta; | ||
417 | /* | ||
418 | * An event which could not be activated because of | ||
419 | * filter mismatch still needs to have its timings | ||
420 | * maintained, otherwise bogus information is return | ||
421 | * via read() for time_enabled, time_running: | ||
422 | */ | ||
423 | if (event->state == PERF_EVENT_STATE_INACTIVE | ||
424 | && !event_filter_match(event)) { | ||
425 | delta = ctx->time - event->tstamp_stopped; | ||
426 | event->tstamp_running += delta; | ||
427 | event->tstamp_stopped = ctx->time; | ||
428 | } | ||
429 | |||
410 | if (event->state != PERF_EVENT_STATE_ACTIVE) | 430 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
411 | return; | 431 | return; |
412 | 432 | ||
@@ -432,9 +452,7 @@ group_sched_out(struct perf_event *group_event, | |||
432 | struct perf_event_context *ctx) | 452 | struct perf_event_context *ctx) |
433 | { | 453 | { |
434 | struct perf_event *event; | 454 | struct perf_event *event; |
435 | 455 | int state = group_event->state; | |
436 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | ||
437 | return; | ||
438 | 456 | ||
439 | event_sched_out(group_event, cpuctx, ctx); | 457 | event_sched_out(group_event, cpuctx, ctx); |
440 | 458 | ||
@@ -444,7 +462,7 @@ group_sched_out(struct perf_event *group_event, | |||
444 | list_for_each_entry(event, &group_event->sibling_list, group_entry) | 462 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
445 | event_sched_out(event, cpuctx, ctx); | 463 | event_sched_out(event, cpuctx, ctx); |
446 | 464 | ||
447 | if (group_event->attr.exclusive) | 465 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
448 | cpuctx->exclusive = 0; | 466 | cpuctx->exclusive = 0; |
449 | } | 467 | } |
450 | 468 | ||