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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31598EB64DC for ; Wed, 28 Jun 2023 19:01:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231563AbjF1TA4 (ORCPT ); Wed, 28 Jun 2023 15:00:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53920 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232438AbjF1S7J (ORCPT ); Wed, 28 Jun 2023 14:59:09 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F27AC2102; Wed, 28 Jun 2023 11:55:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:In-Reply-To:References; bh=6P08QVXXRrbXoyateQxxQCk4bh+paRKekLCZ82zEgH8=; b=url2F0fZ01ji+ds4Rem0FLeG/t 3dBgDzfYIW7OTTtfNLTt4rIH8crndyry4OHdQvZbyIyMr7Ajb+Ot4P1UNdIXGYTPc2hf3qzLWaJFe pspy9msXJ+wykOy3fBGL5CoAAPKY3IE7oB9mUn9o3bCcgNirkUg9veocsCNB8mPWiIf95QyUPcM2U QxocqigmcFUM2BtK2mRWdF665uuL0dFsM3gIdK08lFx8RbxxTfbCJeh3vnoMChqvx3PkZ+mKXLbEM Cg/NaR6/AbFocoTrKu1dv6QzWIfOmOAMf7EZ66V4Xww7T4aQdeNDAnbEs2Fbx5ZHJOwqsGouzITT0 zNLlPUsw==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1qEaKT-0047Ys-Ue; Wed, 28 Jun 2023 18:55:49 +0000 From: "Matthew Wilcox (Oracle)" To: Andrew Morton , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jan Kara , Christoph Hellwig Cc: "Matthew Wilcox (Oracle)" Subject: [PATCH] writeback: Account the number of pages written back Date: Wed, 28 Jun 2023 19:55:48 +0100 Message-Id: <20230628185548.981888-1-willy@infradead.org> X-Mailer: git-send-email 2.37.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org nr_to_write is a count of pages, so we need to decrease it by the number of pages in the folio we just wrote, not by 1. Most callers specify either LONG_MAX or 1, so are unaffected, but writeback_sb_inodes() might end up writing 512x as many pages as it asked for. Fixes: 793917d997df ("mm/readahead: Add large folio readahead") Signed-off-by: Matthew Wilcox (Oracle) --- mm/page-writeback.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 1d17fb1ec863..d3f42009bb70 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2434,6 +2434,7 @@ int write_cache_pages(struct address_space *mapping, for (i = 0; i < nr_folios; i++) { struct folio *folio = fbatch.folios[i]; + unsigned long nr; done_index = folio->index; @@ -2471,6 +2472,7 @@ int write_cache_pages(struct address_space *mapping, trace_wbc_writepage(wbc, inode_to_bdi(mapping->host)); error = writepage(folio, wbc, data); + nr = folio_nr_pages(folio); if (unlikely(error)) { /* * Handle errors according to the type of @@ -2489,8 +2491,7 @@ int write_cache_pages(struct address_space *mapping, error = 0; } else if (wbc->sync_mode != WB_SYNC_ALL) { ret = error; - done_index = folio->index + - folio_nr_pages(folio); + done_index = folio->index + nr; done = 1; break; } @@ -2504,7 +2505,8 @@ int write_cache_pages(struct address_space *mapping, * keep going until we have written all the pages * we tagged for writeback prior to entering this loop. */ - if (--wbc->nr_to_write <= 0 && + wbc->nr_to_write -= nr; + if (wbc->nr_to_write <= 0 && wbc->sync_mode == WB_SYNC_NONE) { done = 1; break; -- 2.39.2