1 files changed, 24 insertions, 25 deletions

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index c43f6eabad5..c8ba627c1d6 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -48,6 +48,7 @@ struct perf_guest_info_callbacks {
 #include <linux/cpu.h>
 #include <linux/irq_work.h>
 #include <linux/static_key.h>
+#include <linux/jump_label_ratelimit.h>
 #include <linux/atomic.h>
 #include <linux/sysfs.h>
 #include <linux/perf_regs.h>
@@ -64,30 +65,6 @@ struct perf_raw_record {
 };
 
 /*
- * single taken branch record layout:
- *
- *      from: source instruction (may not always be a branch insn)
- *        to: branch target
- *   mispred: branch target was mispredicted
- * predicted: branch target was predicted
- *
- * support for mispred, predicted is optional. In case it
- * is not supported mispred = predicted = 0.
- *
- *     in_tx: running in a hardware transaction
- *     abort: aborting a hardware transaction
- */
-struct perf_branch_entry {
-	__u64	from;
-	__u64	to;
-	__u64	mispred:1,  /* target mispredicted */
-		predicted:1,/* target predicted */
-		in_tx:1,    /* in transaction */
-		abort:1,    /* transaction abort */
-		reserved:60;
-};
-
-/*
  * branch stack layout:
  *  nr: number of taken branches stored in entries[]
  *
@@ -317,9 +294,31 @@ struct ring_buffer;
  */
 struct perf_event {
 #ifdef CONFIG_PERF_EVENTS
-	struct list_head		group_entry;
+	/*
+	 * entry onto perf_event_context::event_list;
+	 *   modifications require ctx->lock
+	 *   RCU safe iterations.
+	 */
 	struct list_head		event_entry;
+
+	/*
+	 * XXX: group_entry and sibling_list should be mutually exclusive;
+	 * either you're a sibling on a group, or you're the group leader.
+	 * Rework the code to always use the same list element.
+	 *
+	 * Locked for modification by both ctx->mutex and ctx->lock; holding
+	 * either sufficies for read.
+	 */
+	struct list_head		group_entry;
 	struct list_head		sibling_list;
+
+	/*
+	 * We need storage to track the entries in perf_pmu_migrate_context; we
+	 * cannot use the event_entry because of RCU and we want to keep the
+	 * group in tact which avoids us using the other two entries.
+	 */
+	struct list_head		migrate_entry;
+
 	struct hlist_node		hlist_entry;
 	int				nr_siblings;
 	int				group_flags;