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Date:   Wed, 14 Sep 2022 09:29:59 +0000
From:   Hao Lee <haolee.swjtu@gmail.com>
To:     hannes@cmpxchg.org
Cc:     surenb@google.com, peterz@infradead.org, zhaoyang.huang@unisoc.com,
        haolee.swjtu@gmail.com, linux-kernel@vger.kernel.org
Subject: [PATCH] psi: fix possible missing or delayed pending event
Message-ID: <20220914092959.GA20640@haolee.io>
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When a pending event exists and growth is less than the threshold, the
current logic is to skip this trigger without generating event. However,
from e6df4ead85d9 ("psi: fix possible trigger missing in the window"),
our purpose is to generate event as long as pending event exists and the
rate meets the limit. This patch fixes the possible pending-event
missing or delay.

Fixes: e6df4ead85d9 ("psi: fix possible trigger missing in the window")
Signed-off-by: Hao Lee <haolee.swjtu@gmail.com>
---
 kernel/sched/psi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 9711827e3..0bae4ee2b 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -539,7 +539,7 @@ static u64 update_triggers(struct psi_group *group, u64 now)
 
 			/* Calculate growth since last update */
 			growth = window_update(&t->win, now, total[t->state]);
-			if (growth < t->threshold)
+			if (growth < t->threshold && !t->pending_event)
 				continue;
 
 			t->pending_event = true;
-- 
2.21.0