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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 2DDADCA9EA9 for ; Fri, 18 Oct 2019 21:54:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E0C3720700 for ; Fri, 18 Oct 2019 21:54:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PVLMysH0" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0C3720700 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8C7C98E0005; Fri, 18 Oct 2019 17:54:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 879D68E0003; Fri, 18 Oct 2019 17:54:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 741088E0005; Fri, 18 Oct 2019 17:54:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0174.hostedemail.com [216.40.44.174]) by kanga.kvack.org (Postfix) with ESMTP id 5175C8E0003 for ; Fri, 18 Oct 2019 17:54:24 -0400 (EDT) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id A8A3180FA9DD for ; Fri, 18 Oct 2019 21:54:23 +0000 (UTC) X-FDA: 76058259606.24.flock17_6089119c4fb07 X-HE-Tag: flock17_6089119c4fb07 X-Filterd-Recvd-Size: 5018 Received: from mail-qt1-f196.google.com (mail-qt1-f196.google.com [209.85.160.196]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Fri, 18 Oct 2019 21:54:23 +0000 (UTC) Received: by mail-qt1-f196.google.com with SMTP id w14so11227874qto.9 for ; Fri, 18 Oct 2019 14:54:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=x/NuivOaNcoVxSGecvK1Wkc/UqqJxGqtaVPaOthR2x8=; b=PVLMysH0ZgoHbB8ys0h71PvCjq6BoXMmpyc7E3kYu6dUDS/qfK95htRVtkaJH9jH0F mSX0SISUKRjEVV6wtc/sQLngzyFkyrX26j0lRtGMQezlu/+2uIxqazah6sz53SNS0XKM Ri4HGtynzc9X8OPa5RDRpAt7ar9r1cb4KcgKSI9CxjltPdi1F/qLUrK6VxCcfhh+zOy/ ZExxxaE5zQghDP9lkihlIPfYql4LOVSA6z8EiO7orY+2w1MYsZ80OQVikwhIMM9l3FDH 4dL4E0Sor3fijW8SH2FZpsxzyFAdw/RgqdOAgccnl2ZA3xUoQFpjx7AbCiFRCOy28Q8K 4IkA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=x/NuivOaNcoVxSGecvK1Wkc/UqqJxGqtaVPaOthR2x8=; b=rHPL3lxniubWrUjW/VrjdaCPcSUtmeM7EnReq+1wypHzxIv1f7nLVHFJqJBm1Hgb51 Hz7KKDFsnM6s2gbYBpaBvmXYFyAmkeH4Mjyh5rn9llvJRM7eh/7Wv9MykJxXSzeG2Exs u1eLOtt6RbO6fcc+ju1VAcnm7qua9qatzUBCnNen9zmesfuWhFUZxIM9g/+VZCP84P/x NW633icDujLmX5dd8+eMcQQzAYRpX7xv6PEm+fdB4M4UeXqQn2cXh28iaOVJXvFzTA9I fY/lxSOKKtdKh8lTgrtQCyZoNyMmnE+PVR14HSYmGBUexLGUMDtAtAmMWECgUpt1bEPg HN2w== X-Gm-Message-State: APjAAAUhqb3v7DX/eT5g4Tb5wQ1Y5WT4toCQbhf77j+sfu6TIkI592lo 2BlURRK1j77S0zcLnr+e/gmr51FAG+ajaHHvVmU= X-Google-Smtp-Source: APXvYqw6UQGbFGK6oM1Jx+Eq1w8Q45Sy98nmnXn8Bg4aR3D9UWf+fS0HS1BwJJBa7OtrUyeC9NP9fNdol8AT9qvmNKY= X-Received: by 2002:ac8:2a5d:: with SMTP id l29mr12091370qtl.314.1571435662831; Fri, 18 Oct 2019 14:54:22 -0700 (PDT) MIME-Version: 1.0 References: <20191017164223.2762148-1-songliubraving@fb.com> <20191017164223.2762148-5-songliubraving@fb.com> <20191018133231.vifgnueulyo57vpy@box> In-Reply-To: <20191018133231.vifgnueulyo57vpy@box> From: Yang Shi Date: Fri, 18 Oct 2019 14:54:09 -0700 Message-ID: Subject: Re: [PATCH v2 4/5] mm/thp: allow drop THP from page cache To: "Kirill A. Shutemov" Cc: Song Liu , Linux Kernel Mailing List , Linux MM , Andrew Morton , matthew.wilcox@oracle.com, kernel-team@fb.com, william.kucharski@oracle.com, "Kirill A. Shutemov" Content-Type: text/plain; charset="UTF-8" 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 Fri, Oct 18, 2019 at 6:32 AM Kirill A. Shutemov wrote: > > On Thu, Oct 17, 2019 at 02:46:38PM -0700, Yang Shi wrote: > > On Thu, Oct 17, 2019 at 9:42 AM Song Liu wrote: > > > > > > From: "Kirill A. Shutemov" > > > > > > Once a THP is added to the page cache, it cannot be dropped via > > > /proc/sys/vm/drop_caches. Fix this issue with proper handling in > > > invalidate_mapping_pages(). > > > > > > Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS") > > > Signed-off-by: Kirill A. Shutemov > > > Tested-by: Song Liu > > > Signed-off-by: Song Liu > > > --- > > > mm/truncate.c | 12 ++++++++++++ > > > 1 file changed, 12 insertions(+) > > > > > > diff --git a/mm/truncate.c b/mm/truncate.c > > > index 8563339041f6..dd9ebc1da356 100644 > > > --- a/mm/truncate.c > > > +++ b/mm/truncate.c > > > @@ -592,6 +592,16 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping, > > > unlock_page(page); > > > continue; > > > } > > > + > > > + /* Take a pin outside pagevec */ > > > + get_page(page); > > > + > > > + /* > > > + * Drop extra pins before trying to invalidate > > > + * the huge page. > > > + */ > > > + pagevec_remove_exceptionals(&pvec); > > > + pagevec_release(&pvec); > > > > Shall we skip the outer pagevec_remove_exceptions() if it has been done here? > > It will be NOP and skipping would complicate the code. Yes, it would be. Anyway, it looks ok too. Acked-by: Yang Shi > > -- > Kirill A. Shutemov