3 files changed, 42 insertions, 6 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 0c000cb01eeb..f23ca260307f 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -3707,6 +3707,29 @@ static noinline int visit_groups_merge(struct perf_cpu_context *cpuctx,
 	return 0;
 }
 
+static inline bool event_update_userpage(struct perf_event *event)
+{
+	if (likely(!atomic_read(&event->mmap_count)))
+		return false;
+
+	perf_event_update_time(event);
+	perf_set_shadow_time(event, event->ctx);
+	perf_event_update_userpage(event);
+
+	return true;
+}
+
+static inline void group_update_userpage(struct perf_event *group_event)
+{
+	struct perf_event *event;
+
+	if (!event_update_userpage(group_event))
+		return;
+
+	for_each_sibling_event(event, group_event)
+		event_update_userpage(event);
+}
+
 static int merge_sched_in(struct perf_event *event, void *data)
 {
 	struct perf_event_context *ctx = event->ctx;
@@ -3725,14 +3748,15 @@ static int merge_sched_in(struct perf_event *event, void *data)
 	}
 
 	if (event->state == PERF_EVENT_STATE_INACTIVE) {
+		*can_add_hw = 0;
 		if (event->attr.pinned) {
 			perf_cgroup_event_disable(event, ctx);
 			perf_event_set_state(event, PERF_EVENT_STATE_ERROR);
+		} else {
+			ctx->rotate_necessary = 1;
+			perf_mux_hrtimer_restart(cpuctx);
+			group_update_userpage(event);
 		}
-
-		*can_add_hw = 0;
-		ctx->rotate_necessary = 1;
-		perf_mux_hrtimer_restart(cpuctx);
 	}
 
 	return 0;
@@ -6324,6 +6348,8 @@ accounting:
 
 		ring_buffer_attach(event, rb);
 
+		perf_event_update_time(event);
+		perf_set_shadow_time(event, event->ctx);
 		perf_event_init_userpage(event);
 		perf_event_update_userpage(event);
 	} else {
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 49716228efb4..17a653b67006 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -173,16 +173,22 @@ static ssize_t sched_scaling_write(struct file *filp, const char __user *ubuf,
 				   size_t cnt, loff_t *ppos)
 {
 	char buf[16];
+	unsigned int scaling;
 
 	if (cnt > 15)
 		cnt = 15;
 
 	if (copy_from_user(&buf, ubuf, cnt))
 		return -EFAULT;
+	buf[cnt] = '\0';
 
-	if (kstrtouint(buf, 10, &sysctl_sched_tunable_scaling))
+	if (kstrtouint(buf, 10, &scaling))
 		return -EINVAL;
 
+	if (scaling >= SCHED_TUNABLESCALING_END)
+		return -EINVAL;
+
+	sysctl_sched_tunable_scaling = scaling;
 	if (sched_update_scaling())
 		return -EINVAL;
 
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index ff69f245b939..f6a05d9b5443 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4936,8 +4936,12 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
 	/* update hierarchical throttle state */
 	walk_tg_tree_from(cfs_rq->tg, tg_nop, tg_unthrottle_up, (void *)rq);
 
-	if (!cfs_rq->load.weight)
+	/* Nothing to run but something to decay (on_list)? Complete the branch */
+	if (!cfs_rq->load.weight) {
+		if (cfs_rq->on_list)
+			goto unthrottle_throttle;
 		return;
+	}
 
 	task_delta = cfs_rq->h_nr_running;
 	idle_task_delta = cfs_rq->idle_h_nr_running;