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perf/x86: Optimize x86_schedule_events()

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Now that cpuc->event_constraint[] is retained, we can avoid calling
get_event_constraints() over and over again.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra 2019-03-14 13:17:51 +01:00 committed by Ingo Molnar
parent 2c9651c38d
commit 109717de57
2 changed files with 13 additions and 3 deletions
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13
arch/x86/events/core.c
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@ -858,8 +858,17 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
x86_pmu.start_scheduling(cpuc);
for (i = 0, wmin = X86_PMC_IDX_MAX, wmax = 0; i < n; i++) {
c = x86_pmu.get_event_constraints(cpuc, i, cpuc->event_list[i]);
cpuc->event_constraint[i] = c;
c = cpuc->event_constraint[i];
/*
* Request constraints for new events; or for those events that
* have a dynamic constraint -- for those the constraint can
* change due to external factors (sibling state, allow_tfa).
*/
if (!c || (c->flags & PERF_X86_EVENT_DYNAMIC)) {
c = x86_pmu.get_event_constraints(cpuc, i, cpuc->event_list[i]);
cpuc->event_constraint[i] = c;
}
wmin = min(wmin, c->weight);
wmax = max(wmax, c->weight);

3
arch/x86/events/intel/core.c
View File

@ -2945,7 +2945,8 @@ intel_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
* - dynamic constraint: handled by intel_get_excl_constraints()
*/
c2 = __intel_get_event_constraints(cpuc, idx, event);
if (c1 && (c1->flags & PERF_X86_EVENT_DYNAMIC)) {
if (c1) {
WARN_ON_ONCE(!(c1->flags & PERF_X86_EVENT_DYNAMIC));
bitmap_copy(c1->idxmsk, c2->idxmsk, X86_PMC_IDX_MAX);
c1->weight = c2->weight;
c2 = c1;