perf: Undo the per cpu-context timer stuff

Revert the timer per cpu-context timers because of unfortunate
nohz interaction. Fixing that would have been somewhat ugly, so
go back to driving things from the regular tick. Provide a
jiffies interval feature for people who want slower rotations.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20100917093009.519845633@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 2 deletions

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 165287fd2cc4..61b1e2d760fd 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -870,8 +870,8 @@ struct perf_cpu_context {
         struct perf_event_context       *task_ctx;
         int                             active_oncpu;
         int                             exclusive;
-        u64                             timer_interval;
-        struct hrtimer                  timer;
+        struct list_head                rotation_list;
+        int                             jiffies_interval;
 };
 
 struct perf_output_handle {
@@ -1065,6 +1065,7 @@ extern int perf_swevent_get_recursion_context(void);
 extern void perf_swevent_put_recursion_context(int rctx);
 extern void perf_event_enable(struct perf_event *event);
 extern void perf_event_disable(struct perf_event *event);
+extern void perf_event_task_tick(void);
 #else
 static inline void
 perf_event_task_sched_in(struct task_struct *task)                      { }
@@ -1099,6 +1100,7 @@ static inline int  perf_swevent_get_recursion_context(void)		{ return -1; }
 static inline void perf_swevent_put_recursion_context(int rctx)         { }
 static inline void perf_event_enable(struct perf_event *event)          { }
 static inline void perf_event_disable(struct perf_event *event)         { }
+static inline void perf_event_task_tick(void)                           { }
 #endif
 
 #define perf_output_put(handle, x) \