From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753236AbeAaCZO (ORCPT ); Tue, 30 Jan 2018 21:25:14 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:37654 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753146AbeAaCZN (ORCPT ); Tue, 30 Jan 2018 21:25:13 -0500 Subject: Re: [RFC] mm/migrate: Add new migration reason MR_HUGETLB To: Michal Hocko , Anshuman Khandual References: <20180130030714.6790-1-khandual@linux.vnet.ibm.com> <20180130075949.GN21609@dhcp22.suse.cz> Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org From: Anshuman Khandual Date: Wed, 31 Jan 2018 07:55:05 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <20180130075949.GN21609@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 18013102-0040-0000-0000-0000040AA609 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18013102-0041-0000-0000-0000260E3FB0 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2018-01-30_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1801310027 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/30/2018 01:29 PM, Michal Hocko wrote: > On Tue 30-01-18 08:37:14, Anshuman Khandual wrote: >> alloc_contig_range() initiates compaction and eventual migration for >> the purpose of either CMA or HugeTLB allocation. At present, reason >> code remains the same MR_CMA for either of those cases. Lets add a >> new reason code which will differentiate the purpose of migration >> as HugeTLB allocation instead. > Why do we need it? The same reason why we have MR_CMA (maybe some other ones as well) at present, for reporting purpose through traces at the least. It just seemed like same reason code is being used for two different purpose of migration.