From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752164AbeBZEfH (ORCPT ); Sun, 25 Feb 2018 23:35:07 -0500 Received: from mga11.intel.com ([192.55.52.93]:20639 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751978AbeBZEfF (ORCPT ); Sun, 25 Feb 2018 23:35:05 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,396,1515484800"; d="scan'208";a="20336550" Message-ID: <5A938F26.4040901@intel.com> Date: Mon, 26 Feb 2018 12:37:58 +0800 From: Wei Wang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Michal Hocko CC: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-mm@kvack.org, mst@redhat.com, akpm@linux-foundation.org Subject: Re: [PATCH] mm/page_poison: move PAGE_POISON to page_poison.c References: <1518163694-27155-1-git-send-email-wei.w.wang@intel.com> <20180213101615.GO3443@dhcp22.suse.cz> In-Reply-To: <20180213101615.GO3443@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/13/2018 06:16 PM, Michal Hocko wrote: > On Fri 09-02-18 16:08:14, Wei Wang wrote: >> The PAGE_POISON macro is used in page_poison.c only, so avoid exporting >> it. Also remove the "mm/debug-pagealloc.c" related comment, which is >> obsolete. > Why is this an improvement? I thought the whole point of poison.h is to > keep all the poison value at a single place to make them obviously > unique. There isn't a comment explaining why they are exposed. We did this because PAGE_POISON is used by page_poison.c only, it seems not necessary to expose the private values. Why would it be not unique if moved to page_poison.c (on condition that it is only used there)? Best, Wei