Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753630AbbGOU5Q (ORCPT ); Wed, 15 Jul 2015 16:57:16 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:56153 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752581AbbGOU5N (ORCPT ); Wed, 15 Jul 2015 16:57:13 -0400 Date: Wed, 15 Jul 2015 13:57:11 -0700 From: Andrew Morton To: Michal Hocko Cc: Johannes Weiner , Vladimir Davydov , Tejun Heo , , LKML , Michal Hocko Subject: Re: [PATCH 1/5] memcg: export struct mem_cgroup Message-Id: <20150715135711.1778a8c08f2ea9560a7c1f6f@linux-foundation.org> In-Reply-To: <1436958885-18754-2-git-send-email-mhocko@kernel.org> References: <1436958885-18754-1-git-send-email-mhocko@kernel.org> <1436958885-18754-2-git-send-email-mhocko@kernel.org> X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1631 Lines: 38 On Wed, 15 Jul 2015 13:14:41 +0200 Michal Hocko wrote: > mem_cgroup structure is defined in mm/memcontrol.c currently which > means that the code outside of this file has to use external API even > for trivial access stuff. > > This patch exports mm_struct with its dependencies and makes some of the > exported functions inlines. This even helps to reduce the code size a bit > (make defconfig + CONFIG_MEMCG=y) > > text data bss dec hex filename > 12355346 1823792 1089536 15268674 e8fb42 vmlinux.before > 12354970 1823792 1089536 15268298 e8f9ca vmlinux.after > > This is not much (370B) but better than nothing. We also save a function > call in some hot paths like callers of mem_cgroup_count_vm_event which is > used for accounting. > > The patch doesn't introduce any functional changes. > > ... > > include/linux/memcontrol.h | 369 +++++++++++++++++++++++++++++++++++++++++---- Boy, that's a ton of new stuff into the header file. Do we actually *need* to expose all this? Is some other patch dependent on it? If not then perhaps we shouldn't do this - if the code was already this way, I'd be attracted to a patch which was the reverse of this one! There's some risk of build breakage here - just from a quick scan, memcontrol.h is going to need eventfd.h for eventfd_ctx. But what else is needed? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/