perf: Change and simplify ctx::is_active semantics

Instead of tracking if a context is active or not, track which events
of the context are active. By making it a bitmask of
EVENT_PINNED|EVENT_FLEXIBLE we can simplify some of the scheduling
routines since it can avoid adding events that are already active.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110409192141.930282378@chello.nl
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2011-04-09 21:17:45 +02:00 committed by Ingo Molnar
parent 2c29ef0fef
commit db24d33e08

View file

@ -1763,8 +1763,9 @@ static void ctx_sched_out(struct perf_event_context *ctx,
enum event_type_t event_type)
{
struct perf_event *event;
int is_active = ctx->is_active;
ctx->is_active = 0;
ctx->is_active &= ~event_type;
if (likely(!ctx->nr_events))
return;
@ -1774,12 +1775,12 @@ static void ctx_sched_out(struct perf_event_context *ctx,
return;
perf_pmu_disable(ctx->pmu);
if (event_type & EVENT_PINNED) {
if ((is_active & EVENT_PINNED) && (event_type & EVENT_PINNED)) {
list_for_each_entry(event, &ctx->pinned_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
}
if (event_type & EVENT_FLEXIBLE) {
if ((is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE)) {
list_for_each_entry(event, &ctx->flexible_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
}
@ -2058,8 +2059,9 @@ ctx_sched_in(struct perf_event_context *ctx,
struct task_struct *task)
{
u64 now;
int is_active = ctx->is_active;
ctx->is_active = 1;
ctx->is_active |= event_type;
if (likely(!ctx->nr_events))
return;
@ -2070,11 +2072,11 @@ ctx_sched_in(struct perf_event_context *ctx,
* First go through the list and put on any pinned groups
* in order to give them the best chance of going on.
*/
if (event_type & EVENT_PINNED)
if (!(is_active & EVENT_PINNED) && (event_type & EVENT_PINNED))
ctx_pinned_sched_in(ctx, cpuctx);
/* Then walk through the lower prio flexible groups */
if (event_type & EVENT_FLEXIBLE)
if (!(is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE))
ctx_flexible_sched_in(ctx, cpuctx);
}