From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 60ACAC43603 for ; Mon, 10 May 2021 12:33:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2829A6146E for ; Mon, 10 May 2021 12:33:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346234AbhEJMa2 (ORCPT ); Mon, 10 May 2021 08:30:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:44344 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235240AbhEJLKG (ORCPT ); Mon, 10 May 2021 07:10:06 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 941B36143C; Mon, 10 May 2021 11:05:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620644722; bh=dpiciSMR6RISrdvVoW7CrBO0+Jrk4Cgg6GoFd/SA6nE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Z7SM/iP167mVIlFDsj0xIJXCV/7l20Nm0vGkH3kX8X/ksu7aFek2JCit4r9PlPjc1 srtaUl8IgEOWhucLYvdqNgHgib4GFDXgo0PGnU6k3Rw7zBpb5DDsTlOqjcYp9FPJ01 EBwRQsI3zCgsbNwgoKYdWMRvoyVQIKU/GFeKydwY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jan Kara , Paolo Valente , Oleksandr Natalenko , Jens Axboe , Sasha Levin Subject: [PATCH 5.12 198/384] block, bfq: fix weight-raising resume with !low_latency Date: Mon, 10 May 2021 12:19:47 +0200 Message-Id: <20210510102021.407354969@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102014.849075526@linuxfoundation.org> References: <20210510102014.849075526@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Paolo Valente [ Upstream commit 8c544770092a3d7532d01903b75721e537d87001 ] When the io_latency heuristic is off, bfq_queues must not start to be weight-raised. Unfortunately, by mistake, this may happen when the state of a previously weight-raised bfq_queue is resumed after a queue split. This commit fixes this error. Tested-by: Jan Kara Signed-off-by: Paolo Valente Tested-by: Oleksandr Natalenko Link: https://lore.kernel.org/r/20210304174627.161-5-paolo.valente@linaro.org Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/bfq-iosched.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 95586137194e..20ba5db0f61c 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -1012,7 +1012,7 @@ static void bfq_bfqq_resume_state(struct bfq_queue *bfqq, struct bfq_data *bfqd, struct bfq_io_cq *bic, bool bfq_already_existing) { - unsigned int old_wr_coeff = bfqq->wr_coeff; + unsigned int old_wr_coeff = 1; bool busy = bfq_already_existing && bfq_bfqq_busy(bfqq); if (bic->saved_has_short_ttime) @@ -1033,7 +1033,13 @@ bfq_bfqq_resume_state(struct bfq_queue *bfqq, struct bfq_data *bfqd, bfqq->ttime = bic->saved_ttime; bfqq->io_start_time = bic->saved_io_start_time; bfqq->tot_idle_time = bic->saved_tot_idle_time; - bfqq->wr_coeff = bic->saved_wr_coeff; + /* + * Restore weight coefficient only if low_latency is on + */ + if (bfqd->low_latency) { + old_wr_coeff = bfqq->wr_coeff; + bfqq->wr_coeff = bic->saved_wr_coeff; + } bfqq->service_from_wr = bic->saved_service_from_wr; bfqq->wr_start_at_switch_to_srt = bic->saved_wr_start_at_switch_to_srt; bfqq->last_wr_start_finish = bic->saved_last_wr_start_finish; -- 2.30.2