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 D92AEC3F6B0 for ; Thu, 25 Aug 2022 00:49:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231389AbiHYAtS (ORCPT ); Wed, 24 Aug 2022 20:49:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46450 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231349AbiHYAtQ (ORCPT ); Wed, 24 Aug 2022 20:49:16 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A3B1915EA; Wed, 24 Aug 2022 17:49:15 -0700 (PDT) Received: from dggpemm500022.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4MCkn960jfznTfr; Thu, 25 Aug 2022 08:46:53 +0800 (CST) Received: from dggpemm500014.china.huawei.com (7.185.36.153) by dggpemm500022.china.huawei.com (7.185.36.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 25 Aug 2022 08:49:13 +0800 Received: from [10.174.178.120] (10.174.178.120) by dggpemm500014.china.huawei.com (7.185.36.153) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 25 Aug 2022 08:49:12 +0800 Message-ID: Date: Thu, 25 Aug 2022 08:49:12 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.1.2 CC: , , , , , , , , , , , , , , , Subject: Re: [PATCH v2 1/2] mm: Cap zone movable's min wmark to small value Content-Language: en-US To: , References: <20220819093025.105403-1-mawupeng1@huawei.com> <20220819093025.105403-2-mawupeng1@huawei.com> <96433a14-1d2c-739d-95fb-3e3339200dcf@redhat.com> From: mawupeng In-Reply-To: <96433a14-1d2c-739d-95fb-3e3339200dcf@redhat.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.178.120] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpemm500014.china.huawei.com (7.185.36.153) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/8/24 16:10, David Hildenbrand wrote: > On 19.08.22 11:30, Wupeng Ma wrote: >> From: Ma Wupeng >> >> Since min_free_kbytes is based on gfp_zone(GFP_USER) which does not include >> zone movable. However zone movable will get its min share in >> __setup_per_zone_wmarks() which does not make any sense. >> >> And like highmem pages, __GFP_HIGH and PF_MEMALLOC allocations usually >> don't need movable pages, so there is no need to assign min pages for zone >> movable. >> >> Let's cap pages_min for zone movable to a small value here just link >> highmem pages. >> >> Signed-off-by: Ma Wupeng >> --- >> mm/page_alloc.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >> index e5486d47406e..ff644205370f 100644 >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -8638,7 +8638,7 @@ static void __setup_per_zone_wmarks(void) >> >> /* Calculate total number of !ZONE_HIGHMEM pages */ >> for_each_zone(zone) { >> - if (!is_highmem(zone)) >> + if (!is_highmem(zone) && zone_idx(zone) != ZONE_MOVABLE) >> lowmem_pages += zone_managed_pages(zone); >> } >> >> @@ -8648,7 +8648,7 @@ static void __setup_per_zone_wmarks(void) >> spin_lock_irqsave(&zone->lock, flags); >> tmp = (u64)pages_min * zone_managed_pages(zone); >> do_div(tmp, lowmem_pages); >> - if (is_highmem(zone)) { >> + if (is_highmem(zone) || zone_idx(zone) == ZONE_MOVABLE) { >> /* >> * __GFP_HIGH and PF_MEMALLOC allocations usually don't >> * need highmem pages, so cap pages_min to a small > > This kind-off makes sense to me, but I'm not completely sure about all > implications. We most certainly should update the comment as well. Yes, we should certainly do this. Thanks for reviewing. >