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 649981863 for ; Wed, 28 Dec 2022 15:13:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE8E5C433EF; Wed, 28 Dec 2022 15:13:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672240388; bh=udMDw423tMPoLJhSl+vO+UtqlbZFbxkuHR+1iAEP2tM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DaUcrifuHWgWjlwriy9+LnO+oF9MSWzwhnUBvx+reTME/zc0ds6s1//XUhSzsS5ID kVC5pDm2Y4sgpdIpz4bSA9sqjDQ/qS7ATupPUiNhXYop27c+6uw2rGUgviLB1GapeW HRQSnAj3gJfZCBL6k9/8ZPyMFd17OhPiwzPiWTWg= 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 6.1 0116/1146] sched/psi: Fix possible missing or delayed pending event Date: Wed, 28 Dec 2022 15:27:35 +0100 Message-Id: <20221228144333.308334203@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20221228144330.180012208@linuxfoundation.org> References: <20221228144330.180012208@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 ee2ecc081422..7f40d87e8f50 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -539,10 +539,12 @@ 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