perf_counter: add an event_list

I noticed that the counter_list only includes top-level counters, thus
perf_swcounter_event() will miss sw-counters in groups.

Since perf_swcounter_event() also wants an RCU safe list, create a new
event_list that includes all counters and uses RCU list ops and use call_rcu
to free the counter structure.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index dfb4c7ce18b3..08c11a6afebc 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -187,6 +187,7 @@ struct file;
 struct perf_counter {
 #ifdef CONFIG_PERF_COUNTERS
         struct list_head                list_entry;
+        struct list_head                event_entry;
         struct list_head                sibling_list;
         struct perf_counter             *group_leader;
         const struct hw_perf_counter_ops *hw_ops;
@@ -220,6 +221,8 @@ struct perf_counter {
         struct perf_data                *irqdata;
         struct perf_data                *usrdata;
         struct perf_data                data[2];
+
+        struct rcu_head                 rcu_head;
 #endif
 };
 
@@ -243,6 +246,7 @@ struct perf_counter_context {
         struct mutex            mutex;
 
         struct list_head        counter_list;
+        struct list_head        event_list;
         int                     nr_counters;
         int                     nr_active;
         int                     is_active;