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| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2010-03-06 19:49:19 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-03-10 13:22:25 +0100 |
| commit | 32975a4f114be52286f9a5bf6c230dbb8c0e1903 (patch) | |
| tree | a5259dd7fb4cab05c837bace8a735a439bafc904 /kernel/perf_event.c | |
| parent | perf: Rework and fix the arch CPU-hotplug hooks (diff) | |
| download | linux-32975a4f114be52286f9a5bf6c230dbb8c0e1903.tar.xz linux-32975a4f114be52286f9a5bf6c230dbb8c0e1903.zip | |
perf: Optimize perf_disable
Currently we always call hw_perf_disable(), even if its already disabled,
this seems superflous, esp. since it cannot be made NMI safe (see further
patches).
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/perf_event.c')
| -rw-r--r-- | kernel/perf_event.c | 16 |
1 files changed, 3 insertions, 13 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 73329dedb5ad..d8108465397d 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -93,25 +93,15 @@ void __weak perf_event_print_debug(void) { } static DEFINE_PER_CPU(int, perf_disable_count); -void __perf_disable(void) -{ - __get_cpu_var(perf_disable_count)++; -} - -bool __perf_enable(void) -{ - return !--__get_cpu_var(perf_disable_count); -} - void perf_disable(void) { - __perf_disable(); - hw_perf_disable(); + if (!__get_cpu_var(perf_disable_count)++) + hw_perf_disable(); } void perf_enable(void) { - if (__perf_enable()) + if (!--__get_cpu_var(perf_disable_count)) hw_perf_enable(); } |