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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BB2E5C433FE for ; Wed, 29 Sep 2021 10:10:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A30C861407 for ; Wed, 29 Sep 2021 10:10:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245360AbhI2KLw (ORCPT ); Wed, 29 Sep 2021 06:11:52 -0400 Received: from outbound-smtp09.blacknight.com ([46.22.139.14]:49813 "EHLO outbound-smtp09.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245353AbhI2KLu (ORCPT ); Wed, 29 Sep 2021 06:11:50 -0400 Received: from mail.blacknight.com (pemlinmail06.blacknight.ie [81.17.255.152]) by outbound-smtp09.blacknight.com (Postfix) with ESMTPS id ABEA51C3C12 for ; Wed, 29 Sep 2021 11:10:08 +0100 (IST) Received: (qmail 20883 invoked from network); 29 Sep 2021 10:10:08 -0000 Received: from unknown (HELO stampy.112glenside.lan) (mgorman@techsingularity.net@[84.203.17.29]) by 81.17.254.9 with ESMTPA; 29 Sep 2021 10:10:07 -0000 From: Mel Gorman To: Linux-MM Cc: NeilBrown , Theodore Ts'o , Andreas Dilger , "Darrick J . Wong" , Matthew Wilcox , Michal Hocko , Dave Chinner , Rik van Riel , Vlastimil Babka , Johannes Weiner , Jonathan Corbet , Linux-fsdevel , LKML , Mel Gorman Subject: [PATCH 4/5] mm/writeback: Throttle based on page writeback instead of congestion Date: Wed, 29 Sep 2021 11:09:13 +0100 Message-Id: <20210929100914.14704-5-mgorman@techsingularity.net> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210929100914.14704-1-mgorman@techsingularity.net> References: <20210929100914.14704-1-mgorman@techsingularity.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org do_writepages throttles on congestion if the writepages() fails due to a lack of memory but congestion_wait() is partially broken as the congestion state is not updated for all BDIs. This patch stalls waiting for a number of pages to complete writeback that located on the local node. The main weakness is that there is no correlation between the location of the inode's pages and locality but that is still better than congestion_wait. Signed-off-by: Mel Gorman --- mm/page-writeback.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 4812a17b288c..f34f54fcd5b4 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2366,8 +2366,15 @@ int do_writepages(struct address_space *mapping, struct writeback_control *wbc) ret = generic_writepages(mapping, wbc); if ((ret != -ENOMEM) || (wbc->sync_mode != WB_SYNC_ALL)) break; - cond_resched(); - congestion_wait(BLK_RW_ASYNC, HZ/50); + + /* + * Lacking an allocation context or the locality or writeback + * state of any of the inode's pages, throttle based on + * writeback activity on the local node. It's as good a + * guess as any. + */ + reclaim_throttle(NODE_DATA(numa_node_id()), + VMSCAN_THROTTLE_WRITEBACK, HZ/50); } /* * Usually few pages are written by now from those we've just submitted -- 2.31.1