perf_counter: hrtimer based sampling for software time events
Use hrtimers to profile timer based sampling for the software time
counters.
This allows platforms without hardware counter support to still
perform sample based profiling.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index 4b14a8e..dfb4c7c 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -114,6 +114,7 @@
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/spinlock.h>
+#include <linux/hrtimer.h>
#include <asm/atomic.h>
struct task_struct;
@@ -123,12 +124,19 @@
*/
struct hw_perf_counter {
#ifdef CONFIG_PERF_COUNTERS
- u64 config;
- unsigned long config_base;
- unsigned long counter_base;
- int nmi;
- unsigned int idx;
- atomic64_t count; /* software */
+ union {
+ struct { /* hardware */
+ u64 config;
+ unsigned long config_base;
+ unsigned long counter_base;
+ int nmi;
+ unsigned int idx;
+ };
+ union { /* software */
+ atomic64_t count;
+ struct hrtimer hrtimer;
+ };
+ };
atomic64_t prev_count;
u64 irq_period;
atomic64_t period_left;