From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ot1-f70.google.com (mail-ot1-f70.google.com [209.85.210.70]) by kanga.kvack.org (Postfix) with ESMTP id 300CE6B0007 for ; Thu, 25 Oct 2018 02:23:45 -0400 (EDT) Received: by mail-ot1-f70.google.com with SMTP id q23so5286620otl.1 for ; Wed, 24 Oct 2018 23:23:45 -0700 (PDT) Received: from foss.arm.com (foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id k44si3093443otk.44.2018.10.24.23.23.44 for ; Wed, 24 Oct 2018 23:23:44 -0700 (PDT) Subject: Re: [PATCH V3 3/5] mm/hugetlb: Enable arch specific huge page size support for migration References: <1540299721-26484-1-git-send-email-anshuman.khandual@arm.com> <1540299721-26484-4-git-send-email-anshuman.khandual@arm.com> <20181024135639.GH18839@dhcp22.suse.cz> <20181024135859.GI18839@dhcp22.suse.cz> From: Anshuman Khandual Message-ID: Date: Thu, 25 Oct 2018 11:53:34 +0530 MIME-Version: 1.0 In-Reply-To: <20181024135859.GI18839@dhcp22.suse.cz> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, suzuki.poulose@arm.com, punit.agrawal@arm.com, will.deacon@arm.com, Steven.Price@arm.com, steve.capper@arm.com, catalin.marinas@arm.com, akpm@linux-foundation.org, mike.kravetz@oracle.com, n-horiguchi@ah.jp.nec.com On 10/24/2018 07:28 PM, Michal Hocko wrote: > On Wed 24-10-18 15:56:39, Michal Hocko wrote: >> On Tue 23-10-18 18:31:59, Anshuman Khandual wrote: >>> Architectures like arm64 have HugeTLB page sizes which are different than >>> generic sizes at PMD, PUD, PGD level and implemented via contiguous bits. >>> At present these special size HugeTLB pages cannot be identified through >>> macros like (PMD|PUD|PGDIR)_SHIFT and hence chosen not be migrated. >>> >>> Enabling migration support for these special HugeTLB page sizes along with >>> the generic ones (PMD|PUD|PGD) would require identifying all of them on a >>> given platform. A platform specific hook can precisely enumerate all huge >>> page sizes supported for migration. Instead of comparing against standard >>> huge page orders let hugetlb_migration_support() function call a platform >>> hook arch_hugetlb_migration_support(). Default definition for the platform >>> hook maintains existing semantics which checks standard huge page order. >>> But an architecture can choose to override the default and provide support >>> for a comprehensive set of huge page sizes. >>> >>> Reviewed-by: Naoya Horiguchi >>> Signed-off-by: Anshuman Khandual >> >> Acked-by: Michal Hocko > > fat fingers here, should be mhocko@suse.com of course. Sure no problems. As we had discussed earlier and agreed to keep the previous patch "mm/hugetlb: Enable PUD level huge page migration" separate and not fold into this one, I will assume your ACK on it as well unless your disagree.