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 13CDEC433EF for ; Wed, 18 May 2022 23:37:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D6E208D0008; Wed, 18 May 2022 19:37:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C57EA8D0002; Wed, 18 May 2022 19:37:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AF9118D0008; Wed, 18 May 2022 19:37:53 -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 986B78D0002 for ; Wed, 18 May 2022 19:37:53 -0400 (EDT) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 6EC9932C5C for ; Wed, 18 May 2022 23:37:53 +0000 (UTC) X-FDA: 79480478826.30.4A3EA3B Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by imf23.hostedemail.com (Postfix) with ESMTP id 130A81400CF for ; Wed, 18 May 2022 23:37:34 +0000 (UTC) Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 24IN6GVT013659 for ; Wed, 18 May 2022 16:37:51 -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=UBS18O+BsnzFCTIQhXny5YXEO4wIVCIzwj+tQ4lzVAU=; b=Kk1yA29IoHeTQzOk5Z0YomInehR7eRz/cEds+Cfb3ngjghwXRTGZ8yFezu/AdGHqqQHW qmcxx+RPJYfbbQY20GlcvXMBqhDEK7URqp6Yac2tUf7zf1F0IhFxbgqKi/0+EMcjNXrw rMAFqUnod8Uo8K6YzQ9SwjEFRPsv2B6n/c8= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3g4dea3tms-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 18 May 2022 16:37:51 -0700 Received: from twshared8307.18.frc3.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::c) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.28; Wed, 18 May 2022 16:37:50 -0700 Received: by devvm225.atn0.facebook.com (Postfix, from userid 425415) id 0C42BF3ED86D; Wed, 18 May 2022 16:37:13 -0700 (PDT) From: Stefan Roesch To: , , , , CC: , , Subject: [RFC PATCH v3 14/18] mm: Prepare balance_dirty_pages() for async buffered writes Date: Wed, 18 May 2022 16:37:05 -0700 Message-ID: <20220518233709.1937634-15-shr@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220518233709.1937634-1-shr@fb.com> References: <20220518233709.1937634-1-shr@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-ORIG-GUID: c_Pk113vQK4SA51pwfnXwDf2Favvii7Q X-Proofpoint-GUID: c_Pk113vQK4SA51pwfnXwDf2Favvii7Q X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.874,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-05-18_06,2022-05-17_02,2022-02-23_01 X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 130A81400CF X-Stat-Signature: s3ha6byq1a51womebiuaw3r3o1q8fcri Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=fb.com header.s=facebook header.b=Kk1yA29I; spf=none (imf23.hostedemail.com: domain of "prvs=6137e46c81=shr@fb.com" has no SPF policy when checking 67.231.145.42) smtp.mailfrom="prvs=6137e46c81=shr@fb.com"; dmarc=pass (policy=reject) header.from=fb.com X-HE-Tag: 1652917054-372736 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 If balance_dirty_pages() gets called for async buffered write, we don't want to wait. Instead we need to indicate to the caller that throttling is needed so that it can stop writing and offload the rest of the write to a context that can block. Signed-off-by: Jan Kara Signed-off-by: Stefan Roesch --- mm/page-writeback.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 89dcc7d8395a..fc3b79acd90b 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -1545,8 +1545,8 @@ static inline void wb_dirty_limits(struct dirty_thr= ottle_control *dtc) * If we're over `background_thresh' then the writeback threads are woke= n to * perform some writeout. */ -static void balance_dirty_pages(struct bdi_writeback *wb, - unsigned long pages_dirtied) +static int balance_dirty_pages(struct bdi_writeback *wb, + unsigned long pages_dirtied, bool nowait) { struct dirty_throttle_control gdtc_stor =3D { GDTC_INIT(wb) }; struct dirty_throttle_control mdtc_stor =3D { MDTC_INIT(wb, &gdtc_stor)= }; @@ -1566,6 +1566,7 @@ static void balance_dirty_pages(struct bdi_writebac= k *wb, struct backing_dev_info *bdi =3D wb->bdi; bool strictlimit =3D bdi->capabilities & BDI_CAP_STRICTLIMIT; unsigned long start_time =3D jiffies; + int ret =3D 0; =20 for (;;) { unsigned long now =3D jiffies; @@ -1794,6 +1795,10 @@ static void balance_dirty_pages(struct bdi_writeba= ck *wb, period, pause, start_time); + if (nowait) { + ret =3D -EAGAIN; + break; + } __set_current_state(TASK_KILLABLE); wb->dirty_sleep =3D now; io_schedule_timeout(pause); @@ -1825,6 +1830,7 @@ static void balance_dirty_pages(struct bdi_writebac= k *wb, if (fatal_signal_pending(current)) break; } + return ret; } =20 static DEFINE_PER_CPU(int, bdp_ratelimits); @@ -1906,7 +1912,7 @@ void balance_dirty_pages_ratelimited(struct address= _space *mapping) preempt_enable(); =20 if (unlikely(current->nr_dirtied >=3D ratelimit)) - balance_dirty_pages(wb, current->nr_dirtied); + balance_dirty_pages(wb, current->nr_dirtied, false); =20 wb_put(wb); } --=20 2.30.2