From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75E21C43143 for ; Tue, 2 Oct 2018 12:56:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1D3B720684 for ; Tue, 2 Oct 2018 12:56:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1D3B720684 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727816AbeJBTkH (ORCPT ); Tue, 2 Oct 2018 15:40:07 -0400 Received: from foss.arm.com ([217.140.101.70]:36722 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727555AbeJBTkH (ORCPT ); Tue, 2 Oct 2018 15:40:07 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 999DD7A9; Tue, 2 Oct 2018 05:56:54 -0700 (PDT) Received: from [10.163.1.117] (unknown [10.163.1.117]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C81E43F5B7; Tue, 2 Oct 2018 05:56:51 -0700 (PDT) Subject: Re: [PATCH 1/4] mm/hugetlb: Enable PUD level huge page migration To: Suzuki K Poulose , linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: punit.agrawal@arm.com, will.deacon@arm.com, Steven.Price@arm.com, catalin.marinas@arm.com, mhocko@kernel.org, mike.kravetz@oracle.com, n-horiguchi@ah.jp.nec.com References: <1538482531-26883-1-git-send-email-anshuman.khandual@arm.com> <1538482531-26883-2-git-send-email-anshuman.khandual@arm.com> <835085a2-79c2-4eb5-2c10-13bb2893f611@arm.com> From: Anshuman Khandual Message-ID: Date: Tue, 2 Oct 2018 18:26:49 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <835085a2-79c2-4eb5-2c10-13bb2893f611@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/02/2018 06:08 PM, Suzuki K Poulose wrote: > Hi Anshuman > > On 02/10/18 13:15, Anshuman Khandual wrote: >> Architectures like arm64 have PUD level HugeTLB pages for certain configs >> (1GB huge page is PUD based on ARM64_4K_PAGES base page size) that can be >> enabled for migration. It can be achieved through checking for PUD_SHIFT >> order based HugeTLB pages during migration. >> >> Signed-off-by: Anshuman Khandual >> --- >>   include/linux/hugetlb.h | 3 ++- >>   1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h >> index 6b68e34..9c1b77f 100644 >> --- a/include/linux/hugetlb.h >> +++ b/include/linux/hugetlb.h >> @@ -483,7 +483,8 @@ static inline bool hugepage_migration_supported(struct hstate *h) >>   { >>   #ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION >>       if ((huge_page_shift(h) == PMD_SHIFT) || >> -        (huge_page_shift(h) == PGDIR_SHIFT)) >> +        (huge_page_shift(h) == PUD_SHIFT) || > > >> +            (huge_page_shift(h) == PGDIR_SHIFT)) > > nit: Extra Tab ^^. The tab is in there when you apply this patch and all three checks are tab separated in a newline. > Also, if only arm64 supports PUD_SHIFT, should this be added only in the arm64 specific backend, which we introduce later ? Even if with the platform can add this up in the back end, I would think having this on for default fall back function makes it complete.