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 9904EE810DA for ; Wed, 27 Sep 2023 12:08:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231504AbjI0MIc (ORCPT ); Wed, 27 Sep 2023 08:08:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49648 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229901AbjI0MIb (ORCPT ); Wed, 27 Sep 2023 08:08:31 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3C9CBE for ; Wed, 27 Sep 2023 05:08:28 -0700 (PDT) Received: from dggpemm100001.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Rwb1F64NszrT7R; Wed, 27 Sep 2023 20:06:09 +0800 (CST) Received: from [10.174.177.243] (10.174.177.243) by dggpemm100001.china.huawei.com (7.185.36.93) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Wed, 27 Sep 2023 20:08:25 +0800 Message-ID: Date: Wed, 27 Sep 2023 20:08:24 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH -next 8/9] mm: page_alloc: use a folio in free_pages_prepare() Content-Language: en-US From: Kefeng Wang To: David Hildenbrand , Andrew Morton CC: Mike Rapoport , Matthew Wilcox , , , , Zi Yan References: <20230926005254.2861577-1-wangkefeng.wang@huawei.com> <20230926005254.2861577-9-wangkefeng.wang@huawei.com> <75d28233-c8bd-4528-a775-8ccdc7fc3e26@huawei.com> In-Reply-To: <75d28233-c8bd-4528-a775-8ccdc7fc3e26@huawei.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.177.243] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm100001.china.huawei.com (7.185.36.93) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi David and all, On 2023/9/26 17:39, Kefeng Wang wrote: > > > On 2023/9/26 15:49, David Hildenbrand wrote: >> On 26.09.23 02:52, Kefeng Wang wrote: >>> The page should not a tail page in free_pages_prepare(), let's use >>> a folio in free_pages_prepare() to save several compound_head() calls. >>> >>> Signed-off-by: Kefeng Wang >>> --- >>>   mm/page_alloc.c | 15 ++++++++------- >>>   1 file changed, 8 insertions(+), 7 deletions(-) >>> >>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >>> index 06be8821d833..a888b9d57751 100644 >>> --- a/mm/page_alloc.c >>> +++ b/mm/page_alloc.c >>> @@ -1070,6 +1070,7 @@ static __always_inline bool >>> free_pages_prepare(struct page *page, >>>               unsigned int order, fpi_t fpi_flags) >>>   { >>>       int bad = 0; >>> +    struct folio *folio = page_folio(page); >> >> We might have higher-order pages here that are not folios (not >> compound pages). It looks a bit like this function really shouldn't be >> working with folios in the generic way, for that reason. >> >> Wrong level of abstraction in that function. > > Thanks for your point this, also the change also looks unnecessary too, > the main purpose to use a folio in this function is prepared for > converting page_cpupid_reset_last() to folio, as the higher-order pages > the next patch is not right, I will reconsider it. > As David mentioned，free_pages_prepare should not use folio, I won't to convert page_cpupid_reset_last(), that is, only the first 7 patches are reserved, any comments about the above patches, many thanks.