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=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 83B14C433C1 for ; Fri, 19 Mar 2021 15:14:45 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DF28361926 for ; Fri, 19 Mar 2021 15:14:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF28361926 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5A26C6B0075; Fri, 19 Mar 2021 11:14:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 552286B0078; Fri, 19 Mar 2021 11:14:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3A58F6B007D; Fri, 19 Mar 2021 11:14:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0147.hostedemail.com [216.40.44.147]) by kanga.kvack.org (Postfix) with ESMTP id 19A056B0075 for ; Fri, 19 Mar 2021 11:14:44 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id D4ED48249980 for ; Fri, 19 Mar 2021 15:14:43 +0000 (UTC) X-FDA: 77936970846.20.439E9E5 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf08.hostedemail.com (Postfix) with ESMTP id C83918020378 for ; Fri, 19 Mar 2021 15:12:16 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id D5CB461920; Fri, 19 Mar 2021 15:12:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1616166732; bh=uHqXLPYIm+oaU9HFxAoPyIBK42c9sp7ydb4Y3G+Jt1s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KILv1fOLj5Cfx38p4iiKW+7gU2e/vf9Ez0srm1r7Hhok6kyR4FRmrxji3i/+8nBee BNASI2T1YacQ4GbAYiTelsH4+bpEUpf6zEibX9Dhxqd6kFvntbqmk8mtVGYunxZYj1 Yez6iemcqjUQ4pDcNmNDTTjf6rvxNL/8oezo2XLw= Date: Fri, 19 Mar 2021 15:27:52 +0100 From: Greg Kroah-Hartman To: Dmitry Osipenko Cc: Minchan Kim , Andrew Morton , linux-mm , LKML , joaodias@google.com, willy@infradead.org, david@redhat.com, surenb@google.com, John Hubbard , Nicolas Chauvet , "linux-tegra@vger.kernel.org" Subject: Re: [PATCH v4] mm: cma: support sysfs Message-ID: References: <20210309062333.3216138-1-minchan@kernel.org> <33ec18ef-8652-643a-1a53-ff7c3caf4399@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: C83918020378 X-Stat-Signature: uk1sgnq7axs8ts4obe7pzaribfnegdj3 Received-SPF: none (linuxfoundation.org>: No applicable sender policy available) receiver=imf08; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616166736-497694 Content-Transfer-Encoding: quoted-printable 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 Fri, Mar 19, 2021 at 05:19:47PM +0300, Dmitry Osipenko wrote: > 19.03.2021 16:51, Dmitry Osipenko =D0=BF=D0=B8=D1=88=D0=B5=D1=82: > > 19.03.2021 16:47, Greg Kroah-Hartman =D0=BF=D0=B8=D1=88=D0=B5=D1=82: > >> On Fri, Mar 19, 2021 at 04:45:21PM +0300, Dmitry Osipenko wrote: > >>> 19.03.2021 16:42, Greg Kroah-Hartman =D0=BF=D0=B8=D1=88=D0=B5=D1=82= : > >>>> On Fri, Mar 19, 2021 at 04:39:41PM +0300, Dmitry Osipenko wrote: > >>>>> 19.03.2021 15:44, Dmitry Osipenko =D0=BF=D0=B8=D1=88=D0=B5=D1=82: > >>>>> ... > >>>>>>> #include > >>>>>>> +#include > >>>>>>> + > >>>>>>> +struct cma_stat { > >>>>>>> + spinlock_t lock; > >>>>>>> + /* the number of CMA page successful allocations */ > >>>>>>> + unsigned long nr_pages_succeeded; > >>>>>>> + /* the number of CMA page allocation failures */ > >>>>>>> + unsigned long nr_pages_failed; > >>>>>>> + struct kobject kobj; > >>>>>>> +}; > >>>>>>> =20 > >>>>>>> struct cma { > >>>>>>> unsigned long base_pfn; > >>>>>>> @@ -16,6 +26,9 @@ struct cma { > >>>>>>> struct debugfs_u32_array dfs_bitmap; > >>>>>>> #endif > >>>>>>> char name[CMA_MAX_NAME]; > >>>>>>> +#ifdef CONFIG_CMA_SYSFS > >>>>>>> + struct cma_stat *stat; > >>>>>>> +#endif > >>>>> > >>>>> What is the point of allocating stat dynamically? > >>>> > >>>> Because static kobjects make me cry. > >>>> > >>> > >>> I meant that it's already a part of struct cma, it looks like the s= tat > >>> could be embedded into struct cma and then kobj could be initialize= d > >>> separately. > >> > >> But that structure is statically allocated, so it can not be. This = has > >> been discussed in the past threads for when this was reviewed if you= are > >> curious :) > >=20 > > Indeed, I missed that cma_areas[] is static, thank you. > >=20 >=20 > And in this case should be better to make only the kobj allocated > dynamically instead of the whole cma_stat. Why does it matter?