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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 034CDC433E6 for ; Wed, 17 Mar 2021 03:40:21 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8F30664F8F for ; Wed, 17 Mar 2021 03:40:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8F30664F8F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 30BCD6B0070; Tue, 16 Mar 2021 23:40:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 292726B0071; Tue, 16 Mar 2021 23:40:20 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 10F736B0073; Tue, 16 Mar 2021 23:40:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0153.hostedemail.com [216.40.44.153]) by kanga.kvack.org (Postfix) with ESMTP id E8D546B0070 for ; Tue, 16 Mar 2021 23:40:19 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 9EC5F4FF4 for ; Wed, 17 Mar 2021 03:40:19 +0000 (UTC) X-FDA: 77927963358.16.A568B70 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf03.hostedemail.com (Postfix) with ESMTP id 07C73C0007D0 for ; Wed, 17 Mar 2021 03:40:18 +0000 (UTC) IronPort-SDR: l27nFAb4s8bmjC9J1tme50a5+jILd0AWQUj2MluhYvYN4SH0/X4fU+BYDd8ghoFXhtH3/jJR2h 1UMgk1G9dQ4A== X-IronPort-AV: E=McAfee;i="6000,8403,9925"; a="253394637" X-IronPort-AV: E=Sophos;i="5.81,254,1610438400"; d="scan'208";a="253394637" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Mar 2021 20:40:18 -0700 IronPort-SDR: FUGKoGaMedIKFszJHjI6qOR6Gp0cigBVXQvCIhQf3vMtwv/jmZWuIRvWG4fzg34tTfJMhwpIm4 lk17drMTYXDg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.81,254,1610438400"; d="scan'208";a="602075782" Received: from shbuild999.sh.intel.com ([10.239.147.94]) by fmsmga006.fm.intel.com with ESMTP; 16 Mar 2021 20:40:14 -0700 From: Feng Tang To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton Cc: Michal Hocko , Andrea Arcangeli , David Rientjes , Mel Gorman , Mike Kravetz , Randy Dunlap , Vlastimil Babka , Dave Hansen , Ben Widawsky , Andi Kleen , Dan Williams , Feng Tang Subject: [PATCH v4 01/13] mm/mempolicy: Add comment for missing LOCAL Date: Wed, 17 Mar 2021 11:39:58 +0800 Message-Id: <1615952410-36895-2-git-send-email-feng.tang@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1615952410-36895-1-git-send-email-feng.tang@intel.com> References: <1615952410-36895-1-git-send-email-feng.tang@intel.com> X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 07C73C0007D0 X-Stat-Signature: edezwe3ikumjdih8cey8489bnbexui7i Received-SPF: none (intel.com>: No applicable sender policy available) receiver=imf03; identity=mailfrom; envelope-from=""; helo=mga07.intel.com; client-ip=134.134.136.100 X-HE-DKIM-Result: none/none X-HE-Tag: 1615952418-510204 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: From: Ben Widawsky MPOL_LOCAL is a bit weird because it is simply a different name for an existing behavior (preferred policy with no node mask). It has been this way since it was added here: commit 479e2802d09f ("mm: mempolicy: Make MPOL_LOCAL a real policy") It is so similar to MPOL_PREFERRED in fact that when the policy is created in mpol_new, the mode is set as PREFERRED, and an internal state representing LOCAL doesn't exist. To prevent future explorers from scratching their head as to why MPOL_LOCAL isn't defined in the mpol_ops table, add a small comment explaining the situations. v2: Change comment to refer to mpol_new (Michal) Link: https://lore.kernel.org/r/20200630212517.308045-2-ben.widawsky@intel.com Acked-by: Michal Hocko Signed-off-by: Ben Widawsky Signed-off-by: Feng Tang --- mm/mempolicy.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index ab51132..4193566 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -427,6 +427,7 @@ static const struct mempolicy_operations mpol_ops[MPOL_MAX] = { .create = mpol_new_bind, .rebind = mpol_rebind_nodemask, }, + /* [MPOL_LOCAL] - see mpol_new() */ }; static int migrate_page_add(struct page *page, struct list_head *pagelist, -- 2.7.4