From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D1F811863 for ; Wed, 28 Dec 2022 15:06:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5516EC433EF; Wed, 28 Dec 2022 15:06:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672239991; bh=hyw9iTH/H0D6kJE+QzSnNUXjr2YuX9hc9tBhjqu3n0E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j9f0Y5MF5tWYUuawRyOjQX7RXFqgN202zn1jKqvy4AoO+tufr3wdW/G+B8m1BI/ZL hO9T33onJAdFh275K39wXIqPgnMOG3ddtUIAPFZiIVnz360MDdLUciHyYAs2Fu9qaF cmuO8JEqtU6pZ/ofbGwX2buZ7rLFXtKDAJ2zy5HQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hao Lee , "Peter Zijlstra (Intel)" , Suren Baghdasaryan , Sasha Levin Subject: [PATCH 6.0 0105/1073] sched/psi: Fix possible missing or delayed pending event Date: Wed, 28 Dec 2022 15:28:13 +0100 Message-Id: <20221228144330.897656160@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20221228144328.162723588@linuxfoundation.org> References: <20221228144328.162723588@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Hao Lee [ Upstream commit e38f89af6a13e895805febd3a329a13ab7e66fa4 ] 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, no matter what growth is. This patch handles this case properly. Fixes: e6df4ead85d9 ("psi: fix possible trigger missing in the window") Signed-off-by: Hao Lee Signed-off-by: Peter Zijlstra (Intel) Acked-by: Suren Baghdasaryan Link: https://lore.kernel.org/r/20220919072356.GA29069@haolee.io Signed-off-by: Sasha Levin --- kernel/sched/psi.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index ecb4b4ff4ce0..559416a27c0e 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -537,10 +537,12 @@ 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) - continue; + if (!t->pending_event) { + if (growth < t->threshold) + continue; - t->pending_event = true; + t->pending_event = true; + } } /* Limit event signaling to once per window */ if (now < t->last_event_time + t->win.size) -- 2.35.1