[PATCH] sched/core: uclamp: fix wrong condition

From: Qais Yousef
Date: Thu Nov 14 2019 - 16:10:59 EST


uclamp_update_active() should perform the update when
p->uclamp[clamp_id].active is true. But when the logic was inverted in
[1], the if condition wasn't inverted correctly too.

[1] https://lore.kernel.org/lkml/20190902073836.GO2369@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/

Fixes: babbe170e053 ("sched/uclamp: Update CPU's refcount on TG's clamp changes")
Reported-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Signed-off-by: Qais Yousef <qais.yousef@xxxxxxx>
CC: Juri Lelli <juri.lelli@xxxxxxxxxx>
CC: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
CC: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
CC: Steven Rostedt <rostedt@xxxxxxxxxxx>
CC: Ben Segall <bsegall@xxxxxxxxxx>
CC: Mel Gorman <mgorman@xxxxxxx>
CC: Patrick Bellasi <patrick.bellasi@xxxxxxxxxx>
CC: linux-kernel@xxxxxxxxxxxxxxx
---
kernel/sched/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0f2eb3629070..2de53489c909 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1065,7 +1065,7 @@ uclamp_update_active(struct task_struct *p, enum uclamp_id clamp_id)
* affecting a valid clamp bucket, the next time it's enqueued,
* it will already see the updated clamp bucket value.
*/
- if (!p->uclamp[clamp_id].active) {
+ if (p->uclamp[clamp_id].active) {
uclamp_rq_dec_id(rq, p, clamp_id);
uclamp_rq_inc_id(rq, p, clamp_id);
}
--
2.17.1