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 93E67CD68EC for ; Tue, 10 Oct 2023 03:38:51 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 29A0B80040; Mon, 9 Oct 2023 23:38:51 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 222AF80027; Mon, 9 Oct 2023 23:38:51 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1382B80040; Mon, 9 Oct 2023 23:38:51 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 01C9580027 for ; Mon, 9 Oct 2023 23:38:50 -0400 (EDT) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id BDFB01CA81D for ; Tue, 10 Oct 2023 03:38:50 +0000 (UTC) X-FDA: 81328145220.05.D863C48 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.100]) by imf10.hostedemail.com (Postfix) with ESMTP id 7EAB8C0019 for ; Tue, 10 Oct 2023 03:38:48 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=CDH16VHP; spf=pass (imf10.hostedemail.com: domain of ying.huang@intel.com designates 134.134.136.100 as permitted sender) smtp.mailfrom=ying.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1696909128; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=l03LmpsEEQtgEUMgpxJCj/4CDCV0rqj2PEX6zjNAXQs=; b=jE8MVMCigsAHutYM3zZJSY2cShk2CknrL11wSlVFL9PUoZwkf3HoqOZXIeDpqco+33atYT yWHXg61Yz/ub7SXKUZD3oEL6Xm8Y9DMRkWOASK5LudVQOXeuNgD7UORzDfTmDZBA0gNaTS SyUT41yw0H0Zh/b35t+turehlchuVSo= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1696909128; a=rsa-sha256; cv=none; b=F3QrrOkghstXEFhJAxLkp0ylNNW6ou1Y1cqUJfBf8RMUQ4bMBqK9J6gMr4OZMIw6nzVwbH Q7tlmLIsslK6oFUPRiDCm97dmPj04ozxn+zDjszH88t1SwdbYVWLKkkJcWdDr25p3Vuzuf bx+CWEuXdBo+CDZ0m6Xcn4mXgGxIn7M= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=CDH16VHP; spf=pass (imf10.hostedemail.com: domain of ying.huang@intel.com designates 134.134.136.100 as permitted sender) smtp.mailfrom=ying.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696909128; x=1728445128; h=from:to:cc:subject:references:date:in-reply-to: message-id:mime-version; bh=rBNxEXKO+pOeAvL44CpshEm8bQZYocM51QCHssvFplE=; b=CDH16VHPXd8FcAuo8rOYGnZCP1RiqrET0ipCkxrDPfn9ugcygXrkz8UE P962ftEEDUgEAg97TgIKLV1YfEjcVbmESSuFOvV+k0rLACGAg5komfIcj rCtK/usW+sL/122rBgy0osSGVkVMF71F1zX4Am6Gu9+OTzrrCZhjJc1Rn oO2TRbdN44U5q0tz13h7KBXK8BiSI/IcjFIZdqW7gSdHqS/LDtg31OGTt u+0ArqEa2TaMEWlkxpgFs3JOz/ISHmLwHcs1KhCJoJTgxVIBKT3k19C/f JJItfEIocIo4kPGbXLF2LIP970x8gy+aFunnegye4R4zpx7pSymtX9WU2 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10858"; a="450796926" X-IronPort-AV: E=Sophos;i="6.03,211,1694761200"; d="scan'208";a="450796926" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Oct 2023 20:38:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10858"; a="746921928" X-IronPort-AV: E=Sophos;i="6.03,211,1694761200"; d="scan'208";a="746921928" Received: from yhuang6-desk2.sh.intel.com (HELO yhuang6-desk2.ccr.corp.intel.com) ([10.238.208.55]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Oct 2023 20:38:44 -0700 From: "Huang, Ying" To: Zi Yan Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Zi Yan , Andrew Morton , "Matthew Wilcox (Oracle)" , David Hildenbrand , Baolin Wang Subject: Re: [PATCH 1/1] mm/migrate: correct nr_failed in migrate_pages_sync() References: <20231009203231.1715845-1-zi.yan@sent.com> <20231009203231.1715845-2-zi.yan@sent.com> Date: Tue, 10 Oct 2023 11:36:34 +0800 In-Reply-To: <20231009203231.1715845-2-zi.yan@sent.com> (Zi Yan's message of "Mon, 9 Oct 2023 16:32:31 -0400") Message-ID: <87wmvvi1x9.fsf@yhuang6-desk2.ccr.corp.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=ascii X-Stat-Signature: zok14gxi4sopb6r1ggx3u5nmfhdzembi X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 7EAB8C0019 X-Rspam-User: X-HE-Tag: 1696909128-379305 X-HE-Meta: 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 8BUydr7a N6bs0tUTStduo3D6qjsKIDvC7J812u/sIdhybjwLYXa4oVjCqPJcL8yIT7bC2ngn4dIeGrPR3ff6j4q24lGmLfWHzl69Nz853lNGf/WQoGjhE7PuHsPIGRos9dWQNf271QIyDCCi8aSyurfP3BOGGodOmXivP6hlhIWDBHCSZ967GsliOT7rtDM3LabAXcA81jSa9/sgZfvmNuzqfImnNKCrRySDaX659z0IOxPEx0hm2NDvV7QXN9cQOsHSGHENI+zntXxwZQBrq1E3BgDC2N/tEVgJbg5ygwOm4vVu0XKeVvTE/bx6ikRbcoA== 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: Zi Yan writes: > From: Zi Yan > > nr_failed was missing the rc value from migrate_pages_batch() and can > cause a mismatch between migrate_pages() return value and the number of > not migrated pages, i.e., when the return value of migrate_pages() is 0, > there are still pages left in the from page list. It will happen when a > non-PMD THP large folio fails to migrate due to -ENOMEM and is split > successfully but not all the split pages are not migrated, > migrate_pages_batch() would return non-zero, but astats.nr_thp_split = 0. > nr_failed would be 0 and returned to the caller of migrate_pages(), but > the not migrated pages are left in the from page list without being added > back to LRU lists. > > Fixes: 2ef7dbb26990 ("migrate_pages: try migrate in batch asynchronously firstly") > Signed-off-by: Zi Yan > --- > mm/migrate.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/migrate.c b/mm/migrate.c > index c602bf6dec97..5348827bd958 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -1834,7 +1834,7 @@ static int migrate_pages_sync(struct list_head *from, new_folio_t get_new_folio, > return rc; > } > stats->nr_thp_failed += astats.nr_thp_split; > - nr_failed += astats.nr_thp_split; > + nr_failed += rc + astats.nr_thp_split; > /* > * Fall back to migrate all failed folios one by one synchronously. All > * failed folios except split THPs will be retried, so their failure I don't think this is a correct fix. The failed folios will be retried in the following synchronous migration below. To fix the issue, we should track nr_split for all large folios (not only THP), then use nr_failed += astats.nr_split; -- Best Regards, Huang, Ying