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=-4.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 4F29AC433E2 for ; Wed, 24 Mar 2021 03:32:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16F8A6196C for ; Wed, 24 Mar 2021 03:32:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235104AbhCXDbv (ORCPT ); Tue, 23 Mar 2021 23:31:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48606 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235062AbhCXDbf (ORCPT ); Tue, 23 Mar 2021 23:31:35 -0400 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 385D9C061763 for ; Tue, 23 Mar 2021 20:31:35 -0700 (PDT) Received: by mail-pf1-x434.google.com with SMTP id y200so16338624pfb.5 for ; Tue, 23 Mar 2021 20:31:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=j9te7omEbpKZ/N4rlb8wG4FVpFTLsGLsOoHiGZQa/MQ=; b=vA5er0UpZRPIE11eaIlIxYJor2VwhaBGCYr32FNWFPKbvFjNaEM9t7yzW5jrDyT9C4 yZv7GGnhzIAx7XnfwalWMgqfeC7lCdMUuPbEdtP2PW4Nd4pP4jjJkCts0hE9A6ctt0tY qq0iS4S5DGINTxLrsaqQypVEnqcbTbDnr/UBjDDVosozQvUEvl4CkJAmQ2Dm2ZMZehT8 h7bHj8GbwY/ytrJJ3DyUnTEtR5GU1KNURGVPP70bDIXWcudWhgmfFCoqFRysV11rwJC1 k64u0LlfiuacrdGSV+jDVhSLJ/m05dkbwpdjJBRjAB2xWESNH2omF+dE72v1DcwUpgDH dmlg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=j9te7omEbpKZ/N4rlb8wG4FVpFTLsGLsOoHiGZQa/MQ=; b=eGJUJlR78cH09x5AfeEP3DdnN7hmiiJgue/8CxSFgOeIS4x0ZaEWjWmJk49UTF960/ 0afD+2Rpbu4gRDqohly1/pUYYYJdU25wD1pwdN16vklJKfAMSexMPcXpRHDtFgz9FHzk VFv5x/vT4HI1cmEPdAYrRXb3XMSNUu5clZv5DIZ7ZRaJ4Pd8QlwPN9h8JNC2C+8/wo9B 5m/ld8h+lW5P+MDuwEfgnzPDMnzCn7hqYCXbt/rT4pwNCZu1JWQQUrB715zEdggjLdpc E8mkPgs+CN6HSI7rSXFOnHiGeK6NsXRTR+hXUMfGniP1Qa3OnN/8/hH0Rv/j7J7qUFwv J9mg== X-Gm-Message-State: AOAM532ymTi5DboFVewJj8lRS3CCaN5AS2XOS4keITp79iahHNNtjypM Vv18bphmB8Q4GG3IwtBFcW8= X-Google-Smtp-Source: ABdhPJxMn7EGa6KEQcrL6Cy9awi9U1hljgaVowP+kN5H7zJTo4qA5jMFFERacDq6VlECDstvXx3t9Q== X-Received: by 2002:a62:7b83:0:b029:1f1:5ef3:b4d9 with SMTP id w125-20020a627b830000b02901f15ef3b4d9mr1274163pfc.65.1616556694767; Tue, 23 Mar 2021 20:31:34 -0700 (PDT) Received: from google.com ([2620:15c:211:201:7dfa:1e53:536:7976]) by smtp.gmail.com with ESMTPSA id 143sm571513pfx.144.2021.03.23.20.31.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Mar 2021 20:31:33 -0700 (PDT) Sender: Minchan Kim Date: Tue, 23 Mar 2021 20:31:31 -0700 From: Minchan Kim To: Matthew Wilcox Cc: Andrew Morton , linux-mm , LKML , gregkh@linuxfoundation.org, surenb@google.com, joaodias@google.com, jhubbard@nvidia.com, digetx@gmail.com Subject: Re: [PATCH v5] mm: cma: support sysfs Message-ID: References: <20210323195050.2577017-1-minchan@kernel.org> <20210324030224.GO1719932@casper.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210324030224.GO1719932@casper.infradead.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 24, 2021 at 03:02:24AM +0000, Matthew Wilcox wrote: > On Tue, Mar 23, 2021 at 12:50:50PM -0700, Minchan Kim wrote: > > + /* the number of CMA page successful allocations */ > > + atomic64_t nr_pages_succeeded; > > > +void cma_sysfs_alloc_pages_count(struct cma *cma, size_t count) > > +{ > > + atomic64_add(count, &cma->nr_pages_succeeded); > > +} > > I don't understand. A size_t is a byte count. But the variable is called > 'nr_pages'. So which is it, a byte count or a page count? It's page count. I followed the cma_alloc interface since it has size_t count variable for nr_pages. Let's go with unsigned long nr_pages: void cma_sysfs_alloc_pages_count(struct cma *cma, unsigned long nr_pages) > > > +static ssize_t alloc_pages_success_show(struct kobject *kobj, > > + struct kobj_attribute *attr, char *buf) > > +{ > > + struct cma_kobject *cma_kobj = container_of(kobj, > > + struct cma_kobject, kobj); > > + struct cma *cma = cma_kobj->cma; > > + > > + return sysfs_emit(buf, "%llu\n", > > + atomic64_read(&cma->nr_pages_succeeded)); > > ... if it's in bytes, it should probably be reported in kilobytes > and be suffixed with a 'K' like many other stats. >