From: Peter Zijlstra <peterz@infradead.org>
Date: Tue, 5 Sep 2017 13:44:51 +0200
Subject: perf/core: Make sure to update ctx time before using it
Git-commit: 3c5c8711dcb32115156cc7672fa095afa4339eaa
Patch-mainline: v4.15-rc1
References: FATE#326324

We should make sure to update ctx time before we use it to update
event times.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Tony Jones <tonyj@suse.de>
---
 kernel/events/core.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 0f34f2a47eb6..b249e0f197a7 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1893,6 +1893,11 @@ __perf_remove_from_context(struct perf_event *event,
 {
 	unsigned long flags = (unsigned long)info;
 
+	if (ctx->is_active & EVENT_TIME) {
+		update_context_time(ctx);
+		update_cgrp_time_from_cpuctx(cpuctx);
+	}
+
 	event_sched_out(event, cpuctx, ctx);
 	if (flags & DETACH_GROUP)
 		perf_group_detach(event);
@@ -1955,8 +1960,11 @@ static void __perf_event_disable(struct perf_event *event,
 	if (event->state < PERF_EVENT_STATE_INACTIVE)
 		return;
 
-	update_context_time(ctx);
-	update_cgrp_time_from_event(event);
+	if (ctx->is_active & EVENT_TIME) {
+		update_context_time(ctx);
+		update_cgrp_time_from_event(event);
+	}
+
 	update_group_times(event);
 	if (event == event->group_leader)
 		group_sched_out(event, cpuctx, ctx);