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Commit c933c1a6 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
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perf_event: x86: Optimize the fast path a little more 



Remove num from the fast path and save a few ops.

Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <20100122155536.056430539@chello.nl>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 272d30be

arch/x86/kernel/cpu/perf_event.c

+3 −3
Original line number Diff line number Diff line
@@ -1245,9 +1245,9 @@ static inline int is_x86_event(struct perf_event *event) 


static int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)

{

	int i, j, w, num, wmax;

	struct event_constraint *c, *constraints[X86_PMC_IDX_MAX];

	unsigned long used_mask[BITS_TO_LONGS(X86_PMC_IDX_MAX)];

	int i, j, w, wmax, num = 0;

	struct hw_perf_event *hwc;



	bitmap_zero(used_mask, X86_PMC_IDX_MAX);
@@ -1260,7 +1260,7 @@ static int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign) 
	/*

	 * fastpath, try to reuse previous register

	 */

	for (i = 0, num = n; i < n; i++, num--) {

	for (i = 0; i < n; i++) {

		hwc = &cpuc->event_list[i]->hw;

		c = constraints[i];
@@ -1288,7 +1288,7 @@ static int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign) 
		if (assign)

			assign[i] = hwc->idx;

	}

	if (!num)

	if (i == n)

		goto done;



	/*