From patchwork Thu Jun 23 17:51:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 12893096 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 87E0EC433EF for ; Thu, 23 Jun 2022 19:02:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232003AbiFWTCz (ORCPT ); Thu, 23 Jun 2022 15:02:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232755AbiFWTCi (ORCPT ); Thu, 23 Jun 2022 15:02:38 -0400 Received: from mx0a-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93D867A19E for ; Thu, 23 Jun 2022 11:08:16 -0700 (PDT) Received: from pps.filterd (m0089730.ppops.net [127.0.0.1]) by m0089730.ppops.net (8.17.1.5/8.17.1.5) with ESMTP id 25NHup69020497 for ; Thu, 23 Jun 2022 11:08:15 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=+IYV+ohWMnP9Z2WqVp2E+CnW9cqqI1fK3UacqUP+NEU=; b=A7gR5Xw2SOdP/LhUFKnTV5QpJ4jfbl81LezZhYpt5cGZi0n3B5/q0zVgMKm6Mc7Qjn4H DbdOyKNIUkfTWsh0KoxMZZBB7IsZtGD1eEfEEY6cCnsJylDhKS6Lp+Vw+uGV+UsknpJZ cORUIQehKoaQ/xU3BhIBsi2gbhJ+88DQo3s= Received: from maileast.thefacebook.com ([163.114.130.16]) by m0089730.ppops.net (PPS) with ESMTPS id 3gvce7wk0g-5 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 23 Jun 2022 11:08:15 -0700 Received: from twshared1457.37.frc1.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.28; Thu, 23 Jun 2022 11:08:14 -0700 Received: by devvm225.atn0.facebook.com (Postfix, from userid 425415) id 53F3710C5DC48; Thu, 23 Jun 2022 10:52:00 -0700 (PDT) From: Stefan Roesch To: , , , , CC: , , , , , Subject: [RESEND PATCH v9 01/14] mm: Move starting of background writeback into the main balancing loop Date: Thu, 23 Jun 2022 10:51:44 -0700 Message-ID: <20220623175157.1715274-2-shr@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220623175157.1715274-1-shr@fb.com> References: <20220623175157.1715274-1-shr@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: 4txqgqxkIdXnv9ld9o5xqIUWW_aGlitY X-Proofpoint-ORIG-GUID: 4txqgqxkIdXnv9ld9o5xqIUWW_aGlitY X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-06-23_07,2022-06-23_01,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Jan Kara We start background writeback if we are over background threshold after exiting the main loop in balance_dirty_pages(). This may result in basing the decision on already stale values (we may have slept for significant amount of time) and it is also inconvenient for refactoring needed for async dirty throttling. Move the check into the main waiting loop. Signed-off-by: Jan Kara Signed-off-by: Stefan Roesch --- mm/page-writeback.c | 31 ++++++++++++++----------------- 1 file changed, 14 insertions(+), 17 deletions(-) diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 55c2776ae699..e59c523aed1a 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -1627,6 +1627,19 @@ static void balance_dirty_pages(struct bdi_writeback *wb, } } + /* + * In laptop mode, we wait until hitting the higher threshold + * before starting background writeout, and then write out all + * the way down to the lower threshold. So slow writers cause + * minimal disk activity. + * + * In normal mode, we start background writeout at the lower + * background_thresh, to keep the amount of dirty memory low. + */ + if (!laptop_mode && nr_reclaimable > gdtc->bg_thresh && + !writeback_in_progress(wb)) + wb_start_background_writeback(wb); + /* * Throttle it only when the background writeback cannot * catch-up. This avoids (excessively) small writeouts @@ -1657,6 +1670,7 @@ static void balance_dirty_pages(struct bdi_writeback *wb, break; } + /* Start writeback even when in laptop mode */ if (unlikely(!writeback_in_progress(wb))) wb_start_background_writeback(wb); @@ -1823,23 +1837,6 @@ static void balance_dirty_pages(struct bdi_writeback *wb, if (!dirty_exceeded && wb->dirty_exceeded) wb->dirty_exceeded = 0; - - if (writeback_in_progress(wb)) - return; - - /* - * In laptop mode, we wait until hitting the higher threshold before - * starting background writeout, and then write out all the way down - * to the lower threshold. So slow writers cause minimal disk activity. - * - * In normal mode, we start background writeout at the lower - * background_thresh, to keep the amount of dirty memory low. - */ - if (laptop_mode) - return; - - if (nr_reclaimable > gdtc->bg_thresh) - wb_start_background_writeback(wb); } static DEFINE_PER_CPU(int, bdp_ratelimits);