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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 7D872CA9EC1 for ; Mon, 28 Oct 2019 12:55:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 53C4D214D9 for ; Mon, 28 Oct 2019 12:55:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=yandex-team.ru header.i=@yandex-team.ru header.b="vBo73IPU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729018AbfJ1Mz0 (ORCPT ); Mon, 28 Oct 2019 08:55:26 -0400 Received: from forwardcorp1o.mail.yandex.net ([95.108.205.193]:44650 "EHLO forwardcorp1o.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728269AbfJ1MzZ (ORCPT ); Mon, 28 Oct 2019 08:55:25 -0400 Received: from mxbackcorp1g.mail.yandex.net (mxbackcorp1g.mail.yandex.net [IPv6:2a02:6b8:0:1402::301]) by forwardcorp1o.mail.yandex.net (Yandex) with ESMTP id 71BB12E09CF; Mon, 28 Oct 2019 15:55:21 +0300 (MSK) Received: from iva4-c987840161f8.qloud-c.yandex.net (iva4-c987840161f8.qloud-c.yandex.net [2a02:6b8:c0c:3da5:0:640:c987:8401]) by mxbackcorp1g.mail.yandex.net (nwsmtp/Yandex) with ESMTP id 6aykFKr5ke-tJBSrcoG; Mon, 28 Oct 2019 15:55:21 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1572267321; bh=8ZYFRTzWqu504O6KQ7FUcpox3cZWhyoBz5ojDPWSmYE=; h=In-Reply-To:Message-ID:From:Date:References:To:Subject:Cc; b=vBo73IPUe3lrjMad2DFnaYStzbQtHX6+YDN8Zspbs17A3PUhAE2CpNckQRNrj+NQH Fc/ykjTuHoaEP25SzA0GilwBqxkYuDk/Vog1pEEZ+1V9GKWmEN/wj1TMj63mquBT+n 9bq3FElt7uiVv3dj0zaldvpCQ2e4tNqLPw32lFcQ= Authentication-Results: mxbackcorp1g.mail.yandex.net; dkim=pass header.i=@yandex-team.ru Received: from dynamic-red.dhcp.yndx.net (dynamic-red.dhcp.yndx.net [2a02:6b8:0:40c:148a:8f3:5b61:9f4]) by iva4-c987840161f8.qloud-c.yandex.net (nwsmtp/Yandex) with ESMTPSA id HgRUn4uEtY-tJWiB8BI; Mon, 28 Oct 2019 15:55:19 +0300 (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client certificate not present) Subject: Re: [PATCH RFC] fs/fcntl: add fcntl F_GET_RSS To: Florian Weimer 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 References: <157225848971.557.16257813537984792761.stgit@buzz> <87k18p6qjk.fsf@mid.deneb.enyo.de> From: Konstantin Khlebnikov Message-ID: Date: Mon, 28 Oct 2019 15:55:19 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <87k18p6qjk.fsf@mid.deneb.enyo.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-CA Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 28/10/2019 14.46, Florian Weimer wrote: > * Konstantin Khlebnikov: > >> This implements fcntl() for getting amount of resident memory in cache. >> Kernel already maintains counter for each inode, this patch just exposes >> it into userspace. Returned size is in kilobytes like values in procfs. > > I think this needs a 32-bit compat implementation which clamps the > returned value to INT_MAX. > 32-bit machine couldn't hold more than 2TB cache in one file. Even radix tree wouldn't fit into low memory area.