[PATCH 3/6] perf: Round robin groups of events using list_rotate_left()

[Frederic Weisbecker <fweisbec@gmail.com>]

This is more proper that doing it through a list_for_each_entry()
that breaks after the first entry.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
---
 kernel/perf_event.c |   13 +++----------
 1 files changed, 3 insertions(+), 10 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index c9f8a75..d7254f5 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1454,8 +1454,6 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx)
  */
 static void rotate_ctx(struct perf_event_context *ctx)
 {
-	struct perf_event *event;
-
 	if (!ctx->nr_events)
 		return;
 
@@ -1464,15 +1462,10 @@ static void rotate_ctx(struct perf_event_context *ctx)
 	 * Rotate the first entry last (works just fine for group events too):
 	 */
 	perf_disable();
-	list_for_each_entry(event, &ctx->pinned_groups, group_entry) {
-		list_move_tail(&event->group_entry, &ctx->pinned_groups);
-		break;
-	}
 
-	list_for_each_entry(event, &ctx->flexible_groups, group_entry) {
-		list_move_tail(&event->group_entry, &ctx->flexible_groups);
-		break;
-	}
+	list_rotate_left(&ctx->pinned_groups);
+	list_rotate_left(&ctx->flexible_groups);
+
 	perf_enable();
 
 	raw_spin_unlock(&ctx->lock);
-- 
1.6.2.3