Received: by 2002:a05:6a10:8c0a:0:0:0:0 with SMTP id go10csp1720255pxb; Thu, 4 Feb 2021 22:44:26 -0800 (PST) X-Google-Smtp-Source: ABdhPJxl4wg5BN8x/MpMz0RLRNSTJcsTrUFDzG57ag6DNRYRaW6XO2ZOxWQ36fDS6JzaC8Gg4HMB X-Received: by 2002:a50:fe02:: with SMTP id f2mr2097828edt.195.1612507466089; Thu, 04 Feb 2021 22:44:26 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1612507466; cv=none; d=google.com; s=arc-20160816; b=m4NdJeTdIzJiNCcOcBmu0qn/B67V8u/k6wjrzYqT4uOQCbjkR1DhUheR5+DcjJrxbG 3XeiJAMgIt0kQxSmPk0aqU0+iZ0L67WSqmsq6LSQgSIeijEOkkUnNhqtEGp+j+74YNVD ES4sTpjYQZXmv1K9gDWOE+I+zVAJyuKKNPvjXjXz20p4TGUcsJWKXajxKrlg+N2hKXcm 7T3ymrAlhUf54to1z3pJHpHAJ66zfIiBF8Qbg33IOqBo7/xBEBK4YOYv8lBCLlES4I0A 5YHeI2xfbiVrGNq9Dse6DVxAfirlBnzaBP/0qXC273dB6M7P9TdF6XhMPNqXal3d3Yo0 d4iQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:dkim-signature:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:from:references:cc:to:subject; bh=MVQPZX7CqWSAXEBpuiD9KIrZsqcSefGwB9+cJEmNR/U=; b=0LZpfCMDdnmozmLk7X3aH5O23eKG9/3iRGRlV84z2CdNMYdHhQ2nvntITiFIy0GA21 f5pWHxk15p7bbPbJVjkZHZafFEFytYMKGvxYCkfBhVpHz9wSmce64Dg5ZMwvoVpuAtmq itVRlEl10naqxLN4rn/WhUcAGCJTDSzP/TE1RKAfbjq9CXGC1aKbVKoGNtLAyM582YNU c/ylLZNUpWNz8p0cSUh+Aecw0S3r0PvtksBj/Jsz9epBeptuHwYhWV8oBvoREydedmYx lyFNJRS05/ob0S8JKigCwXLOSlftIRAec+WNZ32tsh8BvHP5gF7zyr9ZGMJvIrIz1vqU lxLA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@nvidia.com header.s=n1 header.b=ZFByrRMH; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nvidia.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id e22si5223378edu.9.2021.02.04.22.44.01; Thu, 04 Feb 2021 22:44:26 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@nvidia.com header.s=n1 header.b=ZFByrRMH; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nvidia.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230448AbhBEGl4 (ORCPT + 99 others); Fri, 5 Feb 2021 01:41:56 -0500 Received: from hqnvemgate26.nvidia.com ([216.228.121.65]:3075 "EHLO hqnvemgate26.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230090AbhBEGlz (ORCPT ); Fri, 5 Feb 2021 01:41:55 -0500 Received: from hqmail.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate26.nvidia.com (using TLS: TLSv1.2, AES256-SHA) id ; Thu, 04 Feb 2021 22:41:15 -0800 Received: from [10.2.60.31] (172.20.145.6) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 5 Feb 2021 06:41:15 +0000 Subject: Re: [PATCH] mm: cma: support sysfs To: Minchan Kim CC: Andrew Morton , , , , LKML , linux-mm References: <20210203155001.4121868-1-minchan@kernel.org> <7e7c01a7-27fe-00a3-f67f-8bcf9ef3eae9@nvidia.com>

<87d7ec1f-d892-0491-a2de-3d0feecca647@nvidia.com> <71c4ce84-8be7-49e2-90bd-348762b320b4@nvidia.com> <34110c61-9826-4cbe-8cd4-76f5e7612dbd@nvidia.com> From: John Hubbard Message-ID: Date: Thu, 4 Feb 2021 22:41:14 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:85.0) Gecko/20100101 Thunderbird/85.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [172.20.145.6] X-ClientProxiedBy: HQMAIL107.nvidia.com (172.20.187.13) To HQMAIL107.nvidia.com (172.20.187.13) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1612507275; bh=MVQPZX7CqWSAXEBpuiD9KIrZsqcSefGwB9+cJEmNR/U=; h=Subject:To:CC:References:From:Message-ID:Date:User-Agent: MIME-Version:In-Reply-To:Content-Type:Content-Language: Content-Transfer-Encoding:X-Originating-IP:X-ClientProxiedBy; b=ZFByrRMHweXhGS7HmqX+9r2j16FGVfJ0523O0aw40mEjjCqf7K2AucMH+RRnQ27JC +LlmYuuFNwD9ITf7dCQVWk0MJcfymXZI6xLvtraTM9qeoSG1fANpW/kXnwNYUhdeIF r57DT+MF6BGpsPTF/EIBscJmobATGHQ4uHuGWmgksjIyUnrYYft9Xdt5jHNMMADFDD OYJKTv1uRf3YFls9HvTopvWDcCIVngeRbJtCtPd3279I7Gn94/XkSMsqxo/hgu+G+l +53SVmSbWrx4re2Zew/yDEHji6Fw2YYXxNPqL4+qJj+iFt07EtqXTy+Wz0CLKRXZ05 ze5dYmvkPqx7A== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/4/21 10:24 PM, Minchan Kim wrote: > On Thu, Feb 04, 2021 at 09:49:54PM -0800, John Hubbard wrote: >> On 2/4/21 9:17 PM, Minchan Kim wrote: ... >> # cat vmstat | grep -i cma >> nr_free_cma 261718 >> >> # cat meminfo | grep -i cma >> CmaTotal: 1048576 kB >> CmaFree: 1046872 kB >> >> OK, given that CMA is already in those two locations, maybe we should put >> this information in one or both of those, yes? > > Do you suggest something liks this, for example? > > > cat vmstat | grep -i cma > cma_a_success 125 > cma_a_fail 25 > cma_b_success 130 > cma_b_fail 156 > .. > cma_f_fail xxx > Yes, approximately. I was wondering if this would suffice at least as a baseline: cma_alloc_success 125 cma_alloc_failure 25 ...and then, to see if more is needed, some questions: a) Do you know of an upper bound on how many cma areas there can be (I think Matthew also asked that)? b) Is tracking the cma area really as valuable as other possibilities? We can put "a few" to "several" items here, so really want to get your very favorite bits of information in. If, for example, there can be *lots* of cma areas, then maybe tracking by a range of allocation sizes is better... thanks, -- John Hubbard NVIDIA