From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id 5BAB16B025F for ; Thu, 27 Jul 2017 04:00:39 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id u7so196696399pgo.6 for ; Thu, 27 Jul 2017 01:00:39 -0700 (PDT) Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com. [148.163.156.1]) by mx.google.com with ESMTPS id 189si10598331pfe.678.2017.07.27.01.00.38 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 27 Jul 2017 01:00:38 -0700 (PDT) Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v6R7wvpC030032 for ; Thu, 27 Jul 2017 04:00:37 -0400 Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) by mx0a-001b2d01.pphosted.com with ESMTP id 2byc080sxb-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 27 Jul 2017 04:00:37 -0400 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 27 Jul 2017 04:00:36 -0400 Subject: Re: gigantic hugepages vs. movable zones References: <20170726105004.GI2981@dhcp22.suse.cz> <87inie1uwf.fsf@linux.vnet.ibm.com> <20170727072857.GI20970@dhcp22.suse.cz> From: "Aneesh Kumar K.V" Date: Thu, 27 Jul 2017 13:30:31 +0530 MIME-Version: 1.0 In-Reply-To: <20170727072857.GI20970@dhcp22.suse.cz> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Message-Id: <1529e986-5f28-35dd-c82e-a4b5801b4afd@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Luiz Capitulino , Mike Kravetz , linux-mm@kvack.org, LKML On 07/27/2017 12:58 PM, Michal Hocko wrote: > On Thu 27-07-17 07:52:08, Aneesh Kumar K.V wrote: >> Michal Hocko writes: >> >>> Hi, >>> I've just noticed that alloc_gigantic_page ignores movability of the >>> gigantic page and it uses any existing zone. Considering that >>> hugepage_migration_supported only supports 2MB and pgd level hugepages >>> then 1GB pages are not migratable and as such allocating them from a >>> movable zone will break the basic expectation of this zone. Standard >>> hugetlb allocations try to avoid that by using htlb_alloc_mask and I >>> believe we should do the same for gigantic pages as well. >>> >>> I suspect this behavior is not intentional. What do you think about the >>> following untested patch? >> >> >> I also noticed an unrelated issue with the usage of >> start_isolate_page_range. On error we set the migrate type to >> MIGRATE_MOVABLE. > > Why that should be a problem? I think it is perfectly OK to have > MIGRATE_MOVABLE pageblocks inside kernel zones. > we can pick pages with migrate type movable and if we fail to isolate won't we set the migrate type of that pages to MOVABLE ? -aneesh -- 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