diff options
| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2010-01-22 18:32:17 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-01-29 11:01:41 +0300 |
| commit | 272d30be622c9c6cbd514b1211ff359292001baa (patch) | |
| tree | 7c792dfbac3a18187c58ba292ecb3af819ef330a | |
| parent | 63b146490befc027a7e0923e333269e68b20d380 (diff) | |
| download | linux-272d30be622c9c6cbd514b1211ff359292001baa.tar.xz | |
perf_event: x86: Optimize constraint weight computation
Add a weight member to the constraint structure and avoid recomputing the
weight at runtime.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <20100122155535.963944926@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index 092ad566734c..2c22ce4fa784 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -23,6 +23,7 @@ #include <linux/uaccess.h> #include <linux/highmem.h> #include <linux/cpu.h> +#include <linux/bitops.h> #include <asm/apic.h> #include <asm/stacktrace.h> @@ -76,6 +77,7 @@ struct event_constraint { }; int code; int cmask; + int weight; }; struct cpu_hw_events { @@ -95,6 +97,7 @@ struct cpu_hw_events { { .idxmsk64[0] = (n) }, \ .code = (c), \ .cmask = (m), \ + .weight = HWEIGHT64((u64)(n)), \ } #define INTEL_EVENT_CONSTRAINT(c, n) \ @@ -1242,8 +1245,7 @@ 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; - int weight, wmax; + 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)]; struct hw_perf_event *hwc; @@ -1320,8 +1322,7 @@ static int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign) c = constraints[i]; hwc = &cpuc->event_list[i]->hw; - weight = bitmap_weight(c->idxmsk, X86_PMC_IDX_MAX); - if (weight != w) + if (c->weight != w) continue; for_each_bit(j, c->idxmsk, X86_PMC_IDX_MAX) { |