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=-6.0 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, 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 BFF99C4360F for ; Fri, 5 Apr 2019 13:37:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7358921852 for ; Fri, 5 Apr 2019 13:37:49 +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="kfqjbeK4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7358921852 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 140406B026B; Fri, 5 Apr 2019 09:37:49 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0EFD76B026C; Fri, 5 Apr 2019 09:37:49 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EFB7B6B026D; Fri, 5 Apr 2019 09:37:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from mail-lf1-f71.google.com (mail-lf1-f71.google.com [209.85.167.71]) by kanga.kvack.org (Postfix) with ESMTP id 8861A6B026B for ; Fri, 5 Apr 2019 09:37:48 -0400 (EDT) Received: by mail-lf1-f71.google.com with SMTP id g2so660424lfh.6 for ; Fri, 05 Apr 2019 06:37:48 -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 :content-transfer-encoding:in-reply-to:user-agent; bh=E0muO+Novkm5hVzyWai7J+6iG5LjzDoURw6tq4KX2tY=; b=pdZBGmhPZ3ysNoFqiK4W/TWdZgTdmHDegiCwJ0SHKQ5/L0/2aHkMeBEtJ4ttkoJMZg h1yFaNFFYQknLUX+RhdYbf3FEhhl9U5BAkR7iL7HDfUqv5fn+DfOjEck7Pj2RPqdVjm6 C6S13XQ7uvf4HQKxybfnTsO4R7GtP+3nRlNLUQBfq6SNpN7wcnxhS0V+M2IxsVaUu6Oy PS2y3d/XRl0HF9rnfEAKIpHp4MUlDg5G4G18eR7wWlghWr/sxFSu+6gmcZpLRwb7yDHU 5oJYrF5A27V5r9vx6eVNZDM2SH92lDDpNsDLk2fkg/XZYWeROFjMx/YCxXq5hKuVLUzo kaDw== X-Gm-Message-State: APjAAAUAoYtPGmS3BQCJYryyZDEkO2RHRpgD0SSh+CIFI/M4tPseWI8b Y5SE7l+E7mNezx8wEZHn7UQvYxYHAr6iUwO8t9XJAf50y7pKmiFa3lv/V7abUDNdIgjIA+zSFQ+ nTsF6GI6V+f2E15hGYGcmPMx2igAxRej36cDXSDB8CeWoJDNHKRKrN7PKaqX0+KX6OQ== X-Received: by 2002:a2e:8347:: with SMTP id l7mr7041018ljh.17.1554471467688; Fri, 05 Apr 2019 06:37:47 -0700 (PDT) X-Received: by 2002:a2e:8347:: with SMTP id l7mr7040972ljh.17.1554471466894; Fri, 05 Apr 2019 06:37:46 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1554471466; cv=none; d=google.com; s=arc-20160816; b=vurxHHhrgNnr6DtXvTXLBbyv0tNevXX+BDmUo4Lloztc/D9B1FW9C9XBvnK+2RQEON m7UhSBOEObHG8Q7PA17b2d2xiNE3LyioPXAdG/gsnTPFsLvy/Oi0S4NuVscg7T2BdNbh lDC+PUpJ5i+SkifRemdXUvSgR6XEdRLcFyXLpDdM0Qbr2dpQNPXmI5V/+jj9omRA7XxT ChL8QbuguN6LYKio2uI7rjhp45hWYC/5LKFvwqdEcPJH1p0AgyZVrPQkNPj9jlJ4IMc8 nKmLjXFm/to4GcLD9/TCGacmQXC0o7+0Sy6x+pzgtYGZNnHD+mS3+TJbqQu0pkKoEJwI 3lpA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-transfer-encoding :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:dkim-signature; bh=E0muO+Novkm5hVzyWai7J+6iG5LjzDoURw6tq4KX2tY=; b=sbap34FaIWj33lJoKjoV2XXYqh+P4VLy8oR7jI1UiPqlNnktpkWL2LFqi7mV2SA/ar M8ogevuT0P/S80lTy0C764h7zwmmLpCaWJg3K2tlODbtjphjSdy44U+c6yM12GMA7Il4 +hEkqY+9oLhbYxU33jhp3vfZnsUgsJ0Vzm7fuxuVUHtXfeL86SUMV54ezZROwodqvErO IPNqcVI+TPLArZFL93RCwXotWhL3GRo1d6IMWec77m5JYr7F/Fwl+aa2YfRkzIS/RW51 84FM01yoBTNJ31gDDd7Mz0BRntuhh293J6J0bQ2+E3z+33U7/mACASDU8i/mOqzisPo3 m6xg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@shutemov-name.20150623.gappssmtp.com header.s=20150623 header.b=kfqjbeK4; 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 v16sor6231163lfi.32.2019.04.05.06.37.46 for (Google Transport Security); Fri, 05 Apr 2019 06:37:46 -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=kfqjbeK4; 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:content-transfer-encoding:in-reply-to :user-agent; bh=E0muO+Novkm5hVzyWai7J+6iG5LjzDoURw6tq4KX2tY=; b=kfqjbeK4svFQQZ3TYPE0Q/bTitqLMsIzhx1KSiEACWF8IX062N5um2XVdUt+NuvLrT lY2C20GCJ+ASJ/0VB3ytybzi2QD2zO67EcE7B38pflEonQ5UP6+NEkH9m9gbf5RvExLZ XtvHfDfNqoIjf5sa800RS4636SOX0Ax4XhpqLP3Lqg2xEO8LDPQYE3LseCEXjGGIOFxR Z5DMIqiMyW0vhQQfV2AxCwFyRWOlDDw/fa/OvgaPYC9nPmiHoO4mOzPObhnY2q5DqF4E i46D4IO58lh5L9ACeTHo9vdoNgVWBvnHB5N1PngpylCFkTccniKxspNYntC9dtEJQ97b kV9w== X-Google-Smtp-Source: APXvYqwtXVMAmYpQa5Benqs8bxw8z6Kxt8PfvJT0s/9svw7Sr+vvGRJyhaFCPwK/mx2RU6Mg1Rm70Q== X-Received: by 2002:a19:e003:: with SMTP id x3mr6966307lfg.66.1554471466384; Fri, 05 Apr 2019 06:37:46 -0700 (PDT) Received: from kshutemo-mobl1.localdomain ([178.127.198.154]) by smtp.gmail.com with ESMTPSA id r27sm4360773lfn.87.2019.04.05.06.37.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 05 Apr 2019 06:37:45 -0700 (PDT) Received: by kshutemo-mobl1.localdomain (Postfix, from userid 1000) id DF64530039B; Fri, 5 Apr 2019 16:37:42 +0300 (+03) Date: Fri, 5 Apr 2019 16:37:42 +0300 From: "Kirill A. Shutemov" To: Qian Cai Cc: Matthew Wilcox , Huang Ying , linux-mm@kvack.org Subject: Re: page cache: Store only head pages in i_pages Message-ID: <20190405133742.goqgpxvbc4jsasz5@kshutemo-mobl1> References: <20190329195941.GW10344@bombadil.infradead.org> <1553894734.26196.30.camel@lca.pw> <20190330030431.GX10344@bombadil.infradead.org> <20190330141052.GZ10344@bombadil.infradead.org> <20190331032326.GA10344@bombadil.infradead.org> <20190401091858.s7clitbvf46nomjm@kshutemo-mobl1> <20190401092716.mxw32y4sl66ywc2o@kshutemo-mobl1> <1554383410.26196.39.camel@lca.pw> <20190404134553.vuvhgmghlkiw2hgl@kshutemo-mobl1> <1554413282.26196.40.camel@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1554413282.26196.40.camel@lca.pw> 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 Thu, Apr 04, 2019 at 05:28:02PM -0400, Qian Cai wrote: > On Thu, 2019-04-04 at 16:45 +0300, Kirill A. Shutemov wrote: > > What about this: > > > > diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h > > index f939e004c5d1..2e8438a1216a 100644 > > --- a/include/linux/pagemap.h > > +++ b/include/linux/pagemap.h > > @@ -335,12 +335,15 @@ static inline struct page *grab_cache_page_nowait(struct > > address_space *mapping, > >   > >  static inline struct page *find_subpage(struct page *page, pgoff_t offset) > >  { > > - unsigned long index = page_index(page); > > + unsigned long mask; > > + > > + if (PageHuge(page)) > > + return page; > >   > >   VM_BUG_ON_PAGE(PageTail(page), page); > > - VM_BUG_ON_PAGE(index > offset, page); > > - VM_BUG_ON_PAGE(index + (1 << compound_order(page)) <= offset, page); > > - return page - index + offset; > > + > > + mask = (1UL << compound_order(page)) - 1; > > + return page + (offset & mask); > >  } > >   > >  struct page *find_get_entry(struct address_space *mapping, pgoff_t offset); > > It works fine. Nice. Matthew, does it look fine to you? -- Kirill A. Shutemov