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 00163C433F5 for ; Wed, 24 Nov 2021 20:44:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 71BC36B0075; Wed, 24 Nov 2021 15:44:27 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 6A4386B0078; Wed, 24 Nov 2021 15:44:27 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 544746B007B; Wed, 24 Nov 2021 15:44:27 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0183.hostedemail.com [216.40.44.183]) by kanga.kvack.org (Postfix) with ESMTP id 41F656B0075 for ; Wed, 24 Nov 2021 15:44:27 -0500 (EST) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 03BC91826964F for ; Wed, 24 Nov 2021 20:44:17 +0000 (UTC) X-FDA: 78845001354.26.60E295F Received: from mail-lj1-f180.google.com (mail-lj1-f180.google.com [209.85.208.180]) by imf18.hostedemail.com (Postfix) with ESMTP id CE9A740020A9 for ; Wed, 24 Nov 2021 20:44:13 +0000 (UTC) Received: by mail-lj1-f180.google.com with SMTP id k2so8050869lji.4 for ; Wed, 24 Nov 2021 12:44:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=K+gJSBFxED6ehQVz3JbYVzRIduuNBjN9QCQBt9+Tl8U=; b=Xtk3yKU4Z9YgRhsjRptKrOtJBPHHf3wchS3ML2iLysLtJ+w1Uc6wlfmpe7Pnl82Th4 YBsPt3B1MG8rPfy1ds/uVHKukORdmc4lM3OCZEm7uG1vQLCfhx7FXOXntG2MMZuZkvRO jPR64FxVuOK7qIlhvSuv8UOMMiI9I9+eE2rQjoDUcz2sbNTB39v6e1NRqBrDk3ISLKts fkG/AL6750Sn06vFu6pkQSGulLQnIcgmpKuaCqjCmvpDwPXLY+EgH8fbZgyVAvnACPtL 6RDIsWexjq+TEaon75yLn3XaLvnH55YB/ory4hheDTz/rguMpecD3PHmbRU5SfUsuHT8 bqYw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=K+gJSBFxED6ehQVz3JbYVzRIduuNBjN9QCQBt9+Tl8U=; b=qMmE0c+Il7saH9ywgAuv3L2me8TBxrn1/DziGmufSqvkv2CKk8OqO8FS0gu+NApsCZ ayY7AEERa/xArs/K5hPymhJLhkSboWdtMy+3X35Yae1x2PGReqn2InuYRxxvXiBxMjTZ pte6hkJtWpVgspRHS/U45sNp8LGcBN7eBCz2GrIff95SDA8bFn3a3OMtFVVXbjK0++P0 LDEdw5Owtwce7flHZVOOoyhQdvi2iDqktUO4zZ/BZ6YCpGZyySx1wHdbQSqewhfwyv9k 4P+oPHlRDdHLuuK5U9zw12M0doNUT5MW3nV0oI3oFRrl0nzOxiIqEzlN/ZEMh//04dJl 4/EA== X-Gm-Message-State: AOAM5326pomU+Z+j8Wdb3qhkMGRc4k/NxSizG+mDIB/9fjgBv5KvoJLM r9fCtBpB3N9DsWXkg6GlOq7ppTyd+Fy6QHdoKZPkTA== X-Google-Smtp-Source: ABdhPJwefa8dMgRLrKBulOVpAsBgtFrSTMYXJWcmjQi7W2ymv70SjNCSDyakkVmtTsTGp72ciPfLpU9x3Xz4toKJCE8= X-Received: by 2002:a2e:bd09:: with SMTP id n9mr18622372ljq.40.1637786654861; Wed, 24 Nov 2021 12:44:14 -0800 (PST) MIME-Version: 1.0 References: <20211123190916.1738458-1-shakeelb@google.com> <20211124201238.3xzpy2b5zcv7j23s@box.shutemov.name> In-Reply-To: <20211124201238.3xzpy2b5zcv7j23s@box.shutemov.name> From: Shakeel Butt Date: Wed, 24 Nov 2021 12:44:02 -0800 Message-ID: Subject: Re: [PATCH v2] mm: thp: update split_queue_len correctly To: "Kirill A. Shutemov" Cc: David Hildenbrand , "Kirill A . Shutemov" , Yang Shi , Zi Yan , Matthew Wilcox , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: CE9A740020A9 X-Stat-Signature: kd138yknjfcw9eji8ccj7wyaw3mtk5yj Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=Xtk3yKU4; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf18.hostedemail.com: domain of shakeelb@google.com designates 209.85.208.180 as permitted sender) smtp.mailfrom=shakeelb@google.com X-Rspamd-Server: rspam02 X-HE-Tag: 1637786653-204959 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: On Wed, Nov 24, 2021 at 12:12 PM Kirill A. Shutemov wrote: > > On Tue, Nov 23, 2021 at 11:09:16AM -0800, Shakeel Butt wrote: > > The deferred THPs are split on memory pressure through shrinker > > callback and splitting of THP during reclaim can fail for several > > reasons like unable to lock the THP, under writeback or unexpected > > number of pins on the THP. Such pages are put back on the deferred split > > list for consideration later. However kernel does not update the > > deferred queue size on putting back the pages whose split was failed. > > This patch fixes that. > > Hm. No. split_huge_page_to_list() updates the queue size on split success. > Right. This is really convoluted. split_huge_page_to_list() is just assuming that if the given page is on a deferred list then it must be on the list returned by get_deferred_split_queue(page). The interaction of move_charge and deferred split seems broken. Andrew, can you please drop this patch?