From patchwork Tue Jan 26 10:51:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Valente X-Patchwork-Id: 12046101 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 011E1C433E0 for ; Tue, 26 Jan 2021 10:53:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B6FBE23109 for ; Tue, 26 Jan 2021 10:53:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404532AbhAZKwz (ORCPT ); Tue, 26 Jan 2021 05:52:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404523AbhAZKwr (ORCPT ); Tue, 26 Jan 2021 05:52:47 -0500 Received: from mail-wm1-x331.google.com (mail-wm1-x331.google.com [IPv6:2a00:1450:4864:20::331]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B8B65C061793 for ; Tue, 26 Jan 2021 02:51:23 -0800 (PST) Received: by mail-wm1-x331.google.com with SMTP id j18so2037187wmi.3 for ; Tue, 26 Jan 2021 02:51:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=g0MXCokkbnaIDoDqUI9Wq5P/6nCekdb4/ZayF5jaU44=; b=vj1b6NidgsO3AAvLOcErxLumqmJkTgHblZ2YHQzhzjKBenORxnL05KJV+vzV+/H4M1 qD6TVraUtAGqfx+BhiM51UH0O0bGE8/UfsSJZnn5kKjpc5/sATZAj7MKszmX3BfeSGaL 39KVXY5Igy9YDb4tUpgwnvpqoBk/6P7U1l5wAsmey3oYSlYUM6wELOk9KKELCJhtF4Yc hIQU5oavrd7La/YTBNrrkM61cRzuzJvruQS8Po/Zl4YyakHcj19xuU4V79xaFl2bf1I+ 9Xo4QuJu7tg4OS/Rco/9Y/OQQS3ntIOFkCISszXN+onU2Mb7mnabTUXTUvfUZ3Sqhm52 hD6g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=g0MXCokkbnaIDoDqUI9Wq5P/6nCekdb4/ZayF5jaU44=; b=fRT9wAE+BOfbcizLHhqkFWTtfLBh0RKhtQgZBxj2phJOJbE+5AdYAP6Nwg3SGCB4cE jt/C/5Xw8g6eYsHaY5aN/+yjk888i0v9f6zuDXgHAZB5Q68a/t4uo2gMYrC1w3TohaNR 6tVCN+3UdgBzPAlqZmaMm1vPTjgQTiUQBlPVlEVO6YP233Ja1sagw3CZJ5TnsED1k346 JaBkV1zXLNYXS7jhX27dtuKeL1xv+VHiHOeTIobiFa2nURhnuUvBC28RfAVtsdNNXu7P Oqi/G8QSXdui0JZMrU320hoMBJjg07ozpkvCE9U6vGbqd2qd4D4EiMlOgM9eVC3mkUyR 7Cuw== X-Gm-Message-State: AOAM530IY/BsbvzE3lPHziXf1X41o/AqJGQpWOzAf2pP8+q/ALB3vLQp Q7Nlcgl98F6ef9pDWgYLE12rAvlowkJcoQ== X-Google-Smtp-Source: ABdhPJzK8Zs6frbsR2txsRD/xENvh79/znuNQXhGsBjUQ+py4BQ16PPJQWOtSdFqV0GvmIo8IjaV+g== X-Received: by 2002:a1c:e0d4:: with SMTP id x203mr4071206wmg.160.1611658282468; Tue, 26 Jan 2021 02:51:22 -0800 (PST) Received: from localhost.localdomain ([83.216.184.132]) by smtp.gmail.com with ESMTPSA id h18sm7177879wru.65.2021.01.26.02.51.21 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 26 Jan 2021 02:51:22 -0800 (PST) From: Paolo Valente To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Paolo Valente , Jan Kara Subject: [PATCH BUGFIX/IMPROVEMENT 4/6] block, bfq: fix weight-raising resume with !low_latency Date: Tue, 26 Jan 2021 11:51:00 +0100 Message-Id: <20210126105102.53102-5-paolo.valente@linaro.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210126105102.53102-1-paolo.valente@linaro.org> References: <20210126105102.53102-1-paolo.valente@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org 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 --- 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 c5bda33c0923..0c7e203085f1 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -1010,7 +1010,7 @@ 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) @@ -1031,7 +1031,13 @@ 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;