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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 79696CA9EC0 for ; Mon, 28 Oct 2019 11:10:46 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3AB01208C0 for ; Mon, 28 Oct 2019 11:10:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="C2Fk946f" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3AB01208C0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CBDEB6B0003; Mon, 28 Oct 2019 07:10:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C6EE56B0006; Mon, 28 Oct 2019 07:10:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B368C6B0007; Mon, 28 Oct 2019 07:10:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0074.hostedemail.com [216.40.44.74]) by kanga.kvack.org (Postfix) with ESMTP id 961356B0003 for ; Mon, 28 Oct 2019 07:10:45 -0400 (EDT) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with SMTP id F12016D8C for ; Mon, 28 Oct 2019 11:10:44 +0000 (UTC) X-FDA: 76092925608.05.bone16_669630918819 X-HE-Tag: bone16_669630918819 X-Filterd-Recvd-Size: 2512 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf23.hostedemail.com (Postfix) with ESMTP for ; Mon, 28 Oct 2019 11:10:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=QYRGqons38NtMgtcv+gzyzZCBRvkASR8tK2x6q26fog=; b=C2Fk946fmaN4QY8nAYZ1vMm2I w0+gKnBQrGuUVKOFpgp4SK2A5VKbLkM3ClkVdoLUznnQA0dzuDaj9icom7IfIUBW5ujgQZT8xqSLo vTiFTK5CZQgI9b6lcrtDBgnJCyRuF1avCfiAf7IMcXr6Nij4E/32a21gqi2o+SxkN5tyrkKCSvtDI 4/yE9UG0hGsfX10WoOekfQ8N51JSZQCd3jSPmalVxKYLP/pDxAF2nXeyYsym4IWAFw5xLjDFku72w JXA17Jerqj3nWG+uUa94+7F4+cjrT8ekYPyfJuvu5lyg64HUkwPTXK3VjPlqgcZ5C3Ned657hv4il uw7PAqTww==; Received: from willy by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1iP2uw-0007FD-Nb; Mon, 28 Oct 2019 11:10:34 +0000 Date: Mon, 28 Oct 2019 04:10:34 -0700 From: Matthew Wilcox To: Konstantin Khlebnikov Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Michal Hocko , Alexander Viro , Johannes Weiner , Andrew Morton , Linus Torvalds , Roman Gushchin Subject: Re: [PATCH RFC] fs/fcntl: add fcntl F_GET_RSS Message-ID: <20191028111034.GS2963@bombadil.infradead.org> References: <157225848971.557.16257813537984792761.stgit@buzz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <157225848971.557.16257813537984792761.stgit@buzz> User-Agent: Mutt/1.12.1 (2019-06-15) 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, Oct 28, 2019 at 01:28:09PM +0300, Konstantin Khlebnikov wrote: > + if (dax_mapping(mapping)) > + pages = READ_ONCE(mapping->nrexceptional); > + else > + pages = READ_ONCE(mapping->nrpages); I'm not sure this is the right calculation for DAX files. We haven't allocated any memory for DAX; we're just accessing storage directly. The entries in the page caache are just translation from file offset to physical address.