From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f198.google.com (mail-qt0-f198.google.com [209.85.216.198]) by kanga.kvack.org (Postfix) with ESMTP id F21796B0005 for ; Tue, 30 Jan 2018 21:46:05 -0500 (EST) Received: by mail-qt0-f198.google.com with SMTP id d15so12775732qtg.2 for ; Tue, 30 Jan 2018 18:46:05 -0800 (PST) Received: from aserp2130.oracle.com (aserp2130.oracle.com. [141.146.126.79]) by mx.google.com with ESMTPS id x143si1061319qka.285.2018.01.30.18.46.05 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 30 Jan 2018 18:46:05 -0800 (PST) Subject: Re: [RFC] mm/migrate: Add new migration reason MR_HUGETLB References: <20180130030714.6790-1-khandual@linux.vnet.ibm.com> <20180130075949.GN21609@dhcp22.suse.cz> From: Mike Kravetz Message-ID: <069a5533-2689-6764-2ec5-9ef0a1351860@oracle.com> Date: Tue, 30 Jan 2018 18:40:58 -0800 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Anshuman Khandual , Michal Hocko Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org On 01/30/2018 06:25 PM, Anshuman Khandual wrote: > 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. > I was 'thinking' that we could potentially open up alloc_contig_range() for more general purpose use. Users would not call alloc_contig_range directly, but it would be wrapped in a more user friendly API. Or, perhaps it gets modified and becomes something else. Still just thinking as part of "how do we provide a more general purpose interface for allocation of more than MAX_ORDER contiguous pages?". Not sure that we should be adding to the current alloc_contig_range interface until we decide it is something which will be useful long term. -- Mike Kravetz -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org