提交 c13d38e4 编写于 作者: S Srivatsa S. Bhat 提交者: Ingo Molnar

perf, cpu hotplug: Use cached value of smp_processor_id()

The perf_cpu_notifier() macro invokes smp_processor_id()
multiple times. Optimize it by using a local variable.
Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Reviewed-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: peterz@infradead.org
Cc: acme@ghostprotocols.net
Link: http://lkml.kernel.org/r/20121016075817.3572.76733.stgit@srivatsabhat.in.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
上级 6760bca9
......@@ -803,15 +803,16 @@ static inline void perf_event_task_tick(void) { }
do { \
static struct notifier_block fn##_nb __cpuinitdata = \
{ .notifier_call = fn, .priority = CPU_PRI_PERF }; \
unsigned long cpu = smp_processor_id(); \
unsigned long flags; \
fn(&fn##_nb, (unsigned long)CPU_UP_PREPARE, \
(void *)(unsigned long)smp_processor_id()); \
(void *)(unsigned long)cpu); \
local_irq_save(flags); \
fn(&fn##_nb, (unsigned long)CPU_STARTING, \
(void *)(unsigned long)smp_processor_id()); \
(void *)(unsigned long)cpu); \
local_irq_restore(flags); \
fn(&fn##_nb, (unsigned long)CPU_ONLINE, \
(void *)(unsigned long)smp_processor_id()); \
(void *)(unsigned long)cpu); \
register_cpu_notifier(&fn##_nb); \
} while (0)
......
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