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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE2A3C433EF for ; Mon, 28 Mar 2022 07:23:56 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2C49C8D0002; Mon, 28 Mar 2022 03:23:56 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 274928D0001; Mon, 28 Mar 2022 03:23:56 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 13C1B8D0002; Mon, 28 Mar 2022 03:23:56 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id 02C858D0001 for ; Mon, 28 Mar 2022 03:23:55 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id B33D822A80 for ; Mon, 28 Mar 2022 07:23:55 +0000 (UTC) X-FDA: 79292955588.15.7974634 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by imf18.hostedemail.com (Postfix) with ESMTP id B25671C0032 for ; Mon, 28 Mar 2022 07:23:54 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.56]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4KRkh80r80z1GD2V; Mon, 28 Mar 2022 15:23:36 +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 15.1.2308.21; Mon, 28 Mar 2022 15:23:50 +0800 Subject: Re: [PATCH 2/2] mm/vmscan: make sure wakeup_kswapd with managed zone To: "Huang, Ying" , Wei Yang CC: , , , References: <20220327024101.10378-1-richard.weiyang@gmail.com> <20220327024101.10378-2-richard.weiyang@gmail.com> <8735j2opd9.fsf@yhuang6-desk2.ccr.corp.intel.com> From: Miaohe Lin Message-ID: <8ff6f619-e04a-d785-fa9a-6822c04d4ee1@huawei.com> Date: Mon, 28 Mar 2022 15:23:49 +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: <8735j2opd9.fsf@yhuang6-desk2.ccr.corp.intel.com> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.177.76] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: B25671C0032 X-Stat-Signature: g6u37tmb7tky4krw8mtnreyb6wru7h5u X-Rspam-User: Authentication-Results: imf18.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf18.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com X-HE-Tag: 1648452234-420686 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 2022/3/28 9:08, Huang, Ying wrote: > Hi, Wei, > > Wei Yang writes: > >> wakeup_kswapd() only wake up kswapd when the zone is managed. >> >> For two callers of wakeup_kswapd(), they are node perspective. >> >> * wake_all_kswapds >> * numamigrate_isolate_page >> >> If we picked up a !managed zone, this is not we expected. >> >> This patch makes sure we pick up a managed zone for wakeup_kswapd(). >> >> Signed-off-by: Wei Yang >> --- >> mm/migrate.c | 2 +- >> mm/page_alloc.c | 2 ++ >> 2 files changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/mm/migrate.c b/mm/migrate.c >> index 3d60823afd2d..c4b654c0bdf0 100644 >> --- a/mm/migrate.c >> +++ b/mm/migrate.c >> @@ -2046,7 +2046,7 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page) >> if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING)) >> return 0; >> for (z = pgdat->nr_zones - 1; z >= 0; z--) { >> - if (populated_zone(pgdat->node_zones + z)) >> + if (managed_zone(pgdat->node_zones + z)) > > This looks good to me! Thanks! It seems that we can replace > populated_zone() in migrate_balanced_pgdat() too. Right? This patch looks good to me too. Thanks! BTW: This makes me remember the bewilderment when I read the relevant code. It's very kind of you if you could tell me the difference between managed_zone and populated_zone. IIUC, when the caller relies on the activity from buddy system, managed_zone should always be used. I think there're many places like compaction need to use managed_zone but populated_zone is used now. They might need to change to use managed_zone too. Or am I miss something? Many Thanks. :) > >> break; >> } >> wakeup_kswapd(pgdat->node_zones + z, 0, order, ZONE_MOVABLE); >> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >> index 4c0c4ef94ba0..6656c2d06e01 100644 >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -4674,6 +4674,8 @@ static void wake_all_kswapds(unsigned int order, gfp_t gfp_mask, >> >> for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, highest_zoneidx, >> ac->nodemask) { >> + if (!managed_zone(zone)) >> + continue; >> if (last_pgdat != zone->zone_pgdat) >> wakeup_kswapd(zone, gfp_mask, order, highest_zoneidx); >> last_pgdat = zone->zone_pgdat; > > Best Regards, > Huang, Ying > > . >