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 X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B01FEC43613 for ; Mon, 24 Jun 2019 14:27:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 67F4F2133F for ; Mon, 24 Jun 2019 14:27:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=shutemov-name.20150623.gappssmtp.com header.i=@shutemov-name.20150623.gappssmtp.com header.b="jtU1r3t/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 67F4F2133F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=shutemov.name Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 16CFC8E0006; Mon, 24 Jun 2019 10:27:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 11CA48E0002; Mon, 24 Jun 2019 10:27:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F26628E0006; Mon, 24 Jun 2019 10:27:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by kanga.kvack.org (Postfix) with ESMTP id A74478E0002 for ; Mon, 24 Jun 2019 10:27:43 -0400 (EDT) Received: by mail-ed1-f70.google.com with SMTP id k22so20749564ede.0 for ; Mon, 24 Jun 2019 07:27:43 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:date:from:to:cc:subject :message-id:references:mime-version:content-disposition:in-reply-to :user-agent; bh=nMad3CaCSZkzI4gyvFvbmTY8mwA5a8Sp7vTVJg617is=; b=paGxa3FB/InS0d7Wq84agA6dsugsYOpXMRXeIPsh61vAa9/q1TJYxHTPGYM68BG8r/ ReBINEjtPxgnIXGHH9GL/o3W3qavVdCVkqp+Cx99RN1UeyDYUZhfVw9acTkhcvq+PUhA +bVRnM9k8NONebtq3P0Ys+QL+j5atgoiOoT3/tvhOEs4La8LxG1CsrCYTfU9e6tQLMD5 b/yjzdqmj08LM4bdEe/P8SrO4e8VJGjQ4vlYGNGOGV9d7IT6WMm94TPhBe/V4oVybTWb mjIXeG4c1nCQrYXfwgS/ZQkRPz45DgsaQsrcNNa/bYPYdpt73L3fdePFIKbLtU2tZkKB da0Q== X-Gm-Message-State: APjAAAVhYP2TPPzpqORntD9z0It/npZxXcMmf+EoL75HPqRxc/8YQajR MIEu2vt09nFDxVxTFrup1hjcNKi/baLtpdJvLuNQnewZA1opHMlMV80Oe+7oXm5GDmX9EOO32na SPBoPfS9fk8/ewH1jpEBfIFmEiQ5L0j2Q4NDrpDjiTIp7TnTx4Ohb0Ewgb2/j91GaxA== X-Received: by 2002:a50:94a2:: with SMTP id s31mr125810252eda.290.1561386463271; Mon, 24 Jun 2019 07:27:43 -0700 (PDT) X-Received: by 2002:a50:94a2:: with SMTP id s31mr125810190eda.290.1561386462652; Mon, 24 Jun 2019 07:27:42 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1561386462; cv=none; d=google.com; s=arc-20160816; b=ykqBSSOU5sUegom03SKHmmM3mmXYbPR75aSWuQBB4jj76kThOeUO8vbtwro9gW+1IL GHPUfgSTRTrHPcJYYidZBTV60tcaR3R4COXxO8Tj35lcxJgNDk8C4iXjiBIAR4/I9Byq jJJsHixb4ToePi+vfhUE+0G3AXPavQoIMR7encP9gXu1QK/h/XERDmk9dpv1CzkV/T1N sOVzF2onfy6abeyHYmVkqcls3DQwCbZj7tbDo06mrJVyaa7vqnXLOiaZN8QvKIUATMzW G7mE0x8iiTtYjd8UHpzmoFNrPUGeK7OqeEejjj8yaBA9JeFGhwfl30C9bYvmkBNvkbWF HtpQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:dkim-signature; bh=nMad3CaCSZkzI4gyvFvbmTY8mwA5a8Sp7vTVJg617is=; b=uncfEpp6xzIbHIUf75ZT2zHaNs1B5G0UoZOnJce8S8y6dMCY3YvelG9+wDhkFQNTH3 +YohHsnpaTP9PwenIdz7BHX5kXVqgqs6nB8qlf4y/vQEEVYg7LB/o4zDrVKBlqoYoOpD YidYOFfXc7QCNnPCx8cLSjiz0vDh95u9hEOPlmCNMJkKu0Hep2oJcYT7B2gNZ9OvOpDW qSlzG6JsFhtv5csf7+4KCmq6oxlrzGd/F69a7lQu1flXcxgL5Awvy1FTIRZyOFhHcSnc jXbwAsUINd3Ueerev30TQ4BLqPfKRW9SN8MSeaD8nw7SebaXnAEg0I83PguCe2kg6G6q 7Sbw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@shutemov-name.20150623.gappssmtp.com header.s=20150623 header.b="jtU1r3t/"; spf=neutral (google.com: 209.85.220.65 is neither permitted nor denied by best guess record for domain of kirill@shutemov.name) smtp.mailfrom=kirill@shutemov.name Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id p15sor3433932ejr.10.2019.06.24.07.27.42 for (Google Transport Security); Mon, 24 Jun 2019 07:27:42 -0700 (PDT) Received-SPF: neutral (google.com: 209.85.220.65 is neither permitted nor denied by best guess record for domain of kirill@shutemov.name) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@shutemov-name.20150623.gappssmtp.com header.s=20150623 header.b="jtU1r3t/"; spf=neutral (google.com: 209.85.220.65 is neither permitted nor denied by best guess record for domain of kirill@shutemov.name) smtp.mailfrom=kirill@shutemov.name DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=nMad3CaCSZkzI4gyvFvbmTY8mwA5a8Sp7vTVJg617is=; b=jtU1r3t/2UsWRHp4cHYwBYGPpiZUxz1/KLoBCTrKS4GUbo9DYoiKDE4ko+tPLCvBZu kVU2KDKQj4bZshQa9gZS8SkpWHRzIIr1zMHVlq+h71f92Sb1sMdH5cnBrexMB088xYoj lsqFXhocWNoaRaULy95jAMLyLmMA7bfqik/wFGsDEb1zokXQv1eavf7pI0rdaS0SuOiE 7dXJYQcgVtIul74lHRgtWv1FCERbkHxuQATQxfehC89AGfJA6TAGFluhj8wPparDYqeP dx75xVh4boioNOkMS5RMHsVzHq+Fqmr9V3rUsM9KoOJQYU4Kgjhf0MyUkXvlsYHXp7+O n7Kg== X-Google-Smtp-Source: APXvYqwqid3EK2KULR3HvJOfTxPaV9NVV4GB+bO31X1U4vpGtxWUZczZsb76evJVJFcgmV4mVSqaMg== X-Received: by 2002:a17:906:3c1:: with SMTP id c1mr34162609eja.221.1561386462321; Mon, 24 Jun 2019 07:27:42 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id a8sm3743134edt.56.2019.06.24.07.27.41 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 24 Jun 2019 07:27:41 -0700 (PDT) Received: by box.localdomain (Postfix, from userid 1000) id 0F1161043B3; Mon, 24 Jun 2019 17:27:47 +0300 (+03) Date: Mon, 24 Jun 2019 17:27:47 +0300 From: "Kirill A. Shutemov" To: Song Liu Cc: "linux-mm@kvack.org" , "linux-fsdevel@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "matthew.wilcox@oracle.com" , "kirill.shutemov@linux.intel.com" , Kernel Team , "william.kucharski@oracle.com" , "akpm@linux-foundation.org" , "hdanton@sina.com" Subject: Re: [PATCH v7 5/6] mm,thp: add read-only THP support for (non-shmem) FS Message-ID: <20190624142747.chy5s3nendxktm3l@box> References: <20190623054749.4016638-1-songliubraving@fb.com> <20190623054749.4016638-6-songliubraving@fb.com> <20190624124746.7evd2hmbn3qg3tfs@box> <52BDA50B-7CBF-4333-9D15-0C17FD04F6ED@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52BDA50B-7CBF-4333-9D15-0C17FD04F6ED@fb.com> User-Agent: NeoMutt/20180716 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 Mon, Jun 24, 2019 at 02:01:05PM +0000, Song Liu wrote: > >> @@ -1392,6 +1403,23 @@ static void collapse_file(struct mm_struct *mm, > >> result = SCAN_FAIL; > >> goto xa_unlocked; > >> } > >> + } else if (!page || xa_is_value(page)) { > >> + xas_unlock_irq(&xas); > >> + page_cache_sync_readahead(mapping, &file->f_ra, file, > >> + index, PAGE_SIZE); > >> + lru_add_drain(); > > > > Why? > > isolate_lru_page() is likely to fail if we don't drain the pagevecs. Please add a comment. > >> + page = find_lock_page(mapping, index); > >> + if (unlikely(page == NULL)) { > >> + result = SCAN_FAIL; > >> + goto xa_unlocked; > >> + } > >> + } else if (!PageUptodate(page)) { > > > > Maybe we should try wait_on_page_locked() here before give up? > > Are you referring to the "if (!PageUptodate(page))" case? Yes. -- Kirill A. Shutemov