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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8E42C43334 for ; Wed, 8 Jun 2022 17:18:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id F17406B0072; Wed, 8 Jun 2022 13:18:06 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EC6E36B0073; Wed, 8 Jun 2022 13:18:06 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D8F256B0074; Wed, 8 Jun 2022 13:18:06 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id CABCB6B0072 for ; Wed, 8 Jun 2022 13:18:06 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 9776821518 for ; Wed, 8 Jun 2022 17:18:06 +0000 (UTC) X-FDA: 79555726572.26.B19C40A Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by imf29.hostedemail.com (Postfix) with ESMTP id 1ED9E120060 for ; Wed, 8 Jun 2022 17:18:05 +0000 (UTC) Received: from pps.filterd (m0044010.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 258FPS9i015588 for ; Wed, 8 Jun 2022 10:18:05 -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=RayINXxBvT2rxnITMQ4oZC3cu2ht47zy1jhXkYvLr1qdhQsXVc6QB/LBGa8EzDB+Fhpe BAzenCliN0/RruEAV/EkUsDUvYDTjRBmKh5Or9gnO5D98o3I96raKkUoI2iqyulGNSOR q5p2yncSUr9j0ejOgPIKQh+y/33/b3ysDUg= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3gj13ctwgt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 08 Jun 2022 10:18:04 -0700 Received: from twshared17349.03.ash7.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::e) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.28; Wed, 8 Jun 2022 10:18:03 -0700 Received: by devvm225.atn0.facebook.com (Postfix, from userid 425415) id 96805103BFB57; Wed, 8 Jun 2022 10:17:43 -0700 (PDT) From: Stefan Roesch To: , , , , CC: , , , , Subject: [PATCH v8 01/14] mm: Move starting of background writeback into the main balancing loop Date: Wed, 8 Jun 2022 10:17:28 -0700 Message-ID: <20220608171741.3875418-2-shr@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220608171741.3875418-1-shr@fb.com> References: <20220608171741.3875418-1-shr@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-GUID: WAhzRyIeq5x5gLKpwsdUFpSlNmdsE5yh X-Proofpoint-ORIG-GUID: WAhzRyIeq5x5gLKpwsdUFpSlNmdsE5yh X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.874,Hydra:6.0.517,FMLib:17.11.64.514 definitions=2022-06-08_05,2022-06-07_02,2022-02-23_01 X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 1ED9E120060 X-Stat-Signature: 4zq14msofcnmbf9uaohrkrapa7q8gjqh Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=fb.com header.s=facebook header.b=RayINXxB; dmarc=pass (policy=reject) header.from=fb.com; spf=none (imf29.hostedemail.com: domain of "prvs=7158831454=shr@fb.com" has no SPF policy when checking 67.231.145.42) smtp.mailfrom="prvs=7158831454=shr@fb.com" X-HE-Tag: 1654708685-563182 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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_writeba= ck *wb, } } =20 + /* + * 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_writebac= k *wb, break; } =20 + /* Start writeback even when in laptop mode */ if (unlikely(!writeback_in_progress(wb))) wb_start_background_writeback(wb); =20 @@ -1823,23 +1837,6 @@ static void balance_dirty_pages(struct bdi_writeba= ck *wb, =20 if (!dirty_exceeded && wb->dirty_exceeded) wb->dirty_exceeded =3D 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); } =20 static DEFINE_PER_CPU(int, bdp_ratelimits); --=20 2.30.2