From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by kanga.kvack.org (Postfix) with ESMTP id B81D76B0003 for ; Thu, 25 Oct 2018 03:45:34 -0400 (EDT) Received: by mail-ed1-f70.google.com with SMTP id h48-v6so4208153edh.22 for ; Thu, 25 Oct 2018 00:45:34 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id l21-v6si542724ejs.32.2018.10.25.00.45.33 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 25 Oct 2018 00:45:33 -0700 (PDT) Date: Thu, 25 Oct 2018 09:45:32 +0200 From: Michal Hocko Subject: Re: [PATCH V3 3/5] mm/hugetlb: Enable arch specific huge page size support for migration Message-ID: <20181025074532.GM18839@dhcp22.suse.cz> 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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Anshuman Khandual 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 Thu 25-10-18 11:53:34, Anshuman Khandual wrote: > > > 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. OK with me. -- Michal Hocko SUSE Labs