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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C208EC433EF for ; Fri, 10 Jun 2022 07:09:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346411AbiFJHJo (ORCPT ); Fri, 10 Jun 2022 03:09:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44478 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346369AbiFJHJi (ORCPT ); Fri, 10 Jun 2022 03:09:38 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D8E832239C for ; Fri, 10 Jun 2022 00:09:38 -0700 (PDT) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4LKBp571kXzRhWY; Fri, 10 Jun 2022 15:06:21 +0800 (CST) Received: from [10.174.177.76] (10.174.177.76) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 10 Jun 2022 15:09:35 +0800 Subject: Re: [v3 PATCH 1/7] mm: khugepaged: check THP flag in hugepage_vma_check() To: Yang Shi CC: , , , , , References: <20220606214414.736109-1-shy828301@gmail.com> <20220606214414.736109-2-shy828301@gmail.com> From: Miaohe Lin Message-ID: <85932a40-a05b-3610-5836-aab36d2664f0@huawei.com> Date: Fri, 10 Jun 2022 15:09:35 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20220606214414.736109-2-shy828301@gmail.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.177.76] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/6/7 5:44, Yang Shi wrote: > Currently the THP flag check in hugepage_vma_check() will fallthrough if > the flag is NEVER and VM_HUGEPAGE is set. This is not a problem for now > since all the callers have the flag checked before or can't be invoked if > the flag is NEVER. > > However, the following patch will call hugepage_vma_check() in more > places, for example, page fault, so this flag must be checked in > hugepge_vma_check(). > > Signed-off-by: Yang Shi Reviewed-by: Miaohe Lin Thanks! > --- > mm/khugepaged.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index 671ac7800e53..84b9cf4b9be9 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -458,6 +458,9 @@ bool hugepage_vma_check(struct vm_area_struct *vma, > if (shmem_file(vma->vm_file)) > return shmem_huge_enabled(vma); > > + if (!khugepaged_enabled()) > + return false; > + > /* THP settings require madvise. */ > if (!(vm_flags & VM_HUGEPAGE) && !khugepaged_always()) > return false; >