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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 92B05C44507 for ; Tue, 14 Jul 2026 01:11:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A97216B0088; Mon, 13 Jul 2026 21:11:09 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A46356B008A; Mon, 13 Jul 2026 21:11:09 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 936926B008C; Mon, 13 Jul 2026 21:11:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 6BBA46B0088 for ; Mon, 13 Jul 2026 21:11:09 -0400 (EDT) Received: from smtpin13.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay07.hostedemail.com (Postfix) with ESMTP id E6B5C160226 for ; Tue, 14 Jul 2026 01:11:08 +0000 (UTC) X-FDA: 84985603416.13.94A7484 Received: from out-181.mta1.migadu.com (out-181.mta1.migadu.com [95.215.58.181]) by imf13.hostedemail.com (Postfix) with ESMTP id 89AD820006 for ; Tue, 14 Jul 2026 01:11:06 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=g1eB9y3B; spf=pass (imf13.hostedemail.com: domain of ridong.chen@linux.dev designates 95.215.58.181 as permitted sender) smtp.mailfrom=ridong.chen@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1783991467; b=W+Tg7BrwSyPVq+bM5ITNWSBUA2+Dk4b3oheF8etwTcNIK1OMWSL5cM8YHQXfEPjleBVKev rwW0JKW/Kztx15PSztUsTzd7GWKATANHiA8hlg9x+62+RfBt3uGA3RRVBE7aELMPcjSRs4 qsw/u3J+HiUXGRltWeRFKEdzbWZqycQ= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=g1eB9y3B; spf=pass (imf13.hostedemail.com: domain of ridong.chen@linux.dev designates 95.215.58.181 as permitted sender) smtp.mailfrom=ridong.chen@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1783991467; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=QBTuxEtzTYLRVryCNC/UKY74wgwZyisDAh2aK7ZURZk=; b=QTUGyLsmkEYSBqM4wMC/e/9kX47BwsxFQ/c1GDZkHIgtYUyP9m8zyKM5fq8ep6jYu28E4m ThSpKMh5FARwr1+4s1LY6AaU5cUAlQ32HyU0uuMQUs7iSM2ZJJQxAE4K4cWJE5Si17Pn+y ll6qZNqepkNowdP+/BLz95PtKU6rGbY= Message-ID: <9117db4b-2a7b-41f3-b5e7-db9d6343bc83@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1783991464; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=QBTuxEtzTYLRVryCNC/UKY74wgwZyisDAh2aK7ZURZk=; b=g1eB9y3BOcZwZblAVHaos/wcXy3DKhqfRLmswKAnzYIj7k5fLSyUOp11oj4sbNwb7qZf5D OVQeC6Z25fjQDNt934i+E6iM8eKME7IJcaZ32EqXAi0m56nj+UtEEi9MO7YgS4MX3WZ9ml YHKg9phMJ74p6SrUNcGJpNitn9lZTMc= Date: Tue, 14 Jul 2026 09:10:46 +0800 MIME-Version: 1.0 Subject: Re: [PATCH 2/2] mm: vmscan: fix node reclaim ignoring swappiness parameter To: Barry Song Cc: Andrew Morton , Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Chris Li , Kairui Song , David Hildenbrand , Yuanchu Xie , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Ridong Chen References: <20260711091157.306070-1-ridong.chen@linux.dev> <20260711091157.306070-3-ridong.chen@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Ridong Chen In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 89AD820006 X-Stat-Signature: pwa4snr6aqgfhbqfyxgrjqd48djyue1y X-HE-Tag: 1783991466-841802 X-HE-Meta: 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 0cFJc0wr fh12S+ct2uXjcHKRACASV6HxAvl8+J6n24QrLbH3L2ajt8EUepSmSq6JZbld9+qpSVh5mSPodRzXxWMtEV7CnpJNx1neFkSeJmnWwQ+VwxrnM/3Q2Inddn6oLR0FbStb8FjBLfepNHGRNhZrrhZlywDDh9qjmpleaYKr6y5Zslp3V4vepfzkBstMr720JVaK6ic7QgqqGuMXqR2AluLfwHqbvTPefrZ1Ckyby/YSdD3qe1VXZ+UytN3KaBbJnrW8h3ce5Ny1toSA4XyhcsnxZfZqwSn+tyJStb68/ Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 7/13/2026 11:16 PM, Barry Song wrote: > On Sat, Jul 11, 2026 at 5:12 PM Ridong Chen wrote: >> >> From: Ridong Chen >> >> sc_swappiness() had two separate definitions depending on >> CONFIG_MEMCG. The !CONFIG_MEMCG variant simply returned >> vm_swappiness, ignoring the proactive_swappiness value passed >> through scan_control. This caused the swappiness parameter >> written to /sys/devices/system/node/nodeX/reclaim to have no >> effect when CONFIG_MEMCG is disabled. >> >> Fix this by consolidating sc_swappiness() into a single definition >> that checks sc->proactive_swappiness first, then falls back to >> mem_cgroup_swappiness() which already handles both CONFIG_MEMCG >> and !CONFIG_MEMCG. >> >> Before fix (swappiness=max ignored, mostly file pages reclaimed): >> >> # cat /proc/sys/vm/swappiness >> 60 >> # cat /proc/vmstat | grep pgsteal >> pgsteal_kswapd 0 >> pgsteal_direct 0 >> pgsteal_khugepaged 0 >> pgsteal_proactive 1840 >> pgsteal_anon 25 >> pgsteal_file 1815 >> # echo "64M swappiness=max" > /sys/devices/system/node/node0/reclaim >> # cat /proc/vmstat | grep pgsteal >> pgsteal_kswapd 0 >> pgsteal_direct 0 >> pgsteal_khugepaged 0 >> pgsteal_proactive 18013 >> pgsteal_anon 337 >> pgsteal_file 17676 >> >> After fix (swappiness=max honored, anon pages reclaimed as expected): >> >> # cat /proc/vmstat | grep pgsteal >> pgsteal_kswapd 0 >> pgsteal_direct 0 >> pgsteal_khugepaged 0 >> pgsteal_proactive 0 >> pgsteal_anon 0 >> pgsteal_file 0 >> # echo "64M swappiness=max" > /sys/devices/system/node/node0/reclaim >> # cat /proc/vmstat | grep pgsteal >> pgsteal_kswapd 0 >> pgsteal_direct 0 >> pgsteal_khugepaged 0 >> pgsteal_proactive 16283 >> pgsteal_anon 16283 >> pgsteal_file 0 >> >> Fixes: 68cd9050d871 ("mm: add swappiness= arg to memory.reclaim") >> Signed-off-by: Ridong Chen > > Reviewed-by: Barry Song > > As pointed out by Johannes, the Fixes tag should be > b980077899ea. Hi Johannes and Barry, Thank you for your review. You are right, will update it. -- Best regards Ridong