Commit 08b3068f authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

perf/x86: Add a x86_pmu::limit_period static_call 



Avoid a branch and indirect call.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220829101321.640658334@infradead.org
parent 28f0f3c4

arch/x86/events/core.c

+5 −4
Original line number Diff line number Diff line
@@ -74,6 +74,7 @@ DEFINE_STATIC_CALL_NULL(x86_pmu_read, *x86_pmu.read); 


DEFINE_STATIC_CALL_NULL(x86_pmu_set_period,   *x86_pmu.set_period);

DEFINE_STATIC_CALL_NULL(x86_pmu_update,       *x86_pmu.update);

DEFINE_STATIC_CALL_NULL(x86_pmu_limit_period, *x86_pmu.limit_period);



DEFINE_STATIC_CALL_NULL(x86_pmu_schedule_events,       *x86_pmu.schedule_events);

DEFINE_STATIC_CALL_NULL(x86_pmu_get_event_constraints, *x86_pmu.get_event_constraints);
@@ -1396,8 +1397,7 @@ int x86_perf_event_set_period(struct perf_event *event) 
	if (left > x86_pmu.max_period)

		left = x86_pmu.max_period;



	if (x86_pmu.limit_period)

		x86_pmu.limit_period(event, &left);

	static_call_cond(x86_pmu_limit_period)(event, &left);



	this_cpu_write(pmc_prev_left[idx], left);
@@ -2024,6 +2024,7 @@ static void x86_pmu_static_call_update(void) 


	static_call_update(x86_pmu_set_period, x86_pmu.set_period);

	static_call_update(x86_pmu_update, x86_pmu.update);

	static_call_update(x86_pmu_limit_period, x86_pmu.limit_period);



	static_call_update(x86_pmu_schedule_events, x86_pmu.schedule_events);

	static_call_update(x86_pmu_get_event_constraints, x86_pmu.get_event_constraints);