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=-12.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 9AB2BC433E0 for ; Fri, 29 Jan 2021 11:52:05 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1393364EDE for ; Fri, 29 Jan 2021 11:52:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1393364EDE Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 35CFE6B0005; Fri, 29 Jan 2021 06:52:04 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 30E746B0006; Fri, 29 Jan 2021 06:52:04 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1D4096B006C; Fri, 29 Jan 2021 06:52:04 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0170.hostedemail.com [216.40.44.170]) by kanga.kvack.org (Postfix) with ESMTP id 054536B0005 for ; Fri, 29 Jan 2021 06:52:04 -0500 (EST) Received: from smtpin12.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id B43058249980 for ; Fri, 29 Jan 2021 11:52:03 +0000 (UTC) X-FDA: 77758648926.12.A5A81D0 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by imf01.hostedemail.com (Postfix) with ESMTP id EA53720001E7 for ; Fri, 29 Jan 2021 11:51:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611921119; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FUEN6UTfn53/wX/SEJGh22PWSC8cNFCZ2DPJVW+i4jI=; b=LWjPOKVrhoZxkoFib7du2Nt4lYukFpqcBdjrJ5D4o3nkY6FMki+uyRL9MFukHLkscXTbi3 3RaV0niwNGz7fRJxkfIW/telukZ6/jq61i3XwVhxf/y1v1OxUpHnmmWYwoDe16EsHogMbl 6OLxhcMp1xCABjZ/KO9y3fyd4OaW8eo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-271-OKAhZr8FNw2cV8zOqtPwZg-1; Fri, 29 Jan 2021 06:51:55 -0500 X-MC-Unique: OKAhZr8FNw2cV8zOqtPwZg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EFB14814417; Fri, 29 Jan 2021 11:51:53 +0000 (UTC) Received: from [10.36.113.219] (ovpn-113-219.ams2.redhat.com [10.36.113.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id 76A2E5D9C0; Fri, 29 Jan 2021 11:51:51 +0000 (UTC) Subject: Re: [PATCH v3] mm/page_alloc: count CMA pages per zone and print them in /proc/zoneinfo To: Oscar Salvador Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Thomas Gleixner , "Peter Zijlstra (Intel)" , Mike Rapoport , Michal Hocko , Wei Yang , David Rientjes , linux-api@vger.kernel.org References: <20210127101813.6370-3-david@redhat.com> <20210129113451.22085-1-david@redhat.com> <20210129114624.GA25391@linux> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <8d7fc7f5-58b0-301a-1055-beb0df86b536@redhat.com> Date: Fri, 29 Jan 2021 12:51:50 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <20210129114624.GA25391@linux> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: EA53720001E7 X-Stat-Signature: kasu53jkpdoj8qb7p3an8dyakiop4kwf Received-SPF: none (redhat.com>: No applicable sender policy available) receiver=imf01; identity=mailfrom; envelope-from=""; helo=us-smtp-delivery-124.mimecast.com; client-ip=216.205.24.124 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1611921119-698144 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 29.01.21 12:46, Oscar Salvador wrote: > On Fri, Jan 29, 2021 at 12:34:51PM +0100, David Hildenbrand wrote: >> Let's count the number of CMA pages per zone and print them in >> /proc/zoneinfo. >> >> Having access to the total number of CMA pages per zone is helpful for >> debugging purposes to know where exactly the CMA pages ended up, and to >> figure out how many pages of a zone might behave differently, even after >> some of these pages might already have been allocated. >> >> As one example, CMA pages part of a kernel zone cannot be used for >> ordinary kernel allocations but instead behave more like ZONE_MOVABLE. >> >> For now, we are only able to get the global nr+free cma pages from >> /proc/meminfo and the free cma pages per zone from /proc/zoneinfo. >> >> Example after this patch when booting a 6 GiB QEMU VM with >> "hugetlb_cma=2G": >> # cat /proc/zoneinfo | grep cma >> cma 0 >> nr_free_cma 0 >> cma 0 >> nr_free_cma 0 >> cma 524288 >> nr_free_cma 493016 >> cma 0 >> cma 0 >> # cat /proc/meminfo | grep Cma >> CmaTotal: 2097152 kB >> CmaFree: 1972064 kB >> >> Note: We print even without CONFIG_CMA, just like "nr_free_cma"; this way, >> one can be sure when spotting "cma 0", that there are definetly no >> CMA pages located in a zone. >> >> Cc: Andrew Morton >> Cc: Thomas Gleixner >> Cc: "Peter Zijlstra (Intel)" >> Cc: Mike Rapoport >> Cc: Oscar Salvador >> Cc: Michal Hocko >> Cc: Wei Yang >> Cc: David Rientjes >> Cc: linux-api@vger.kernel.org >> Signed-off-by: David Hildenbrand > > Looks good to me, I guess it is better to print it unconditionally > so the layout does not change. > > Reviewed-by: Oscar Salvador Thanks for the fast review! -- Thanks, David / dhildenb