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 6078DC4453D for ; Thu, 23 Jul 2026 02:59:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3FB9E6B00BA; Wed, 22 Jul 2026 22:59:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3AB576B00BB; Wed, 22 Jul 2026 22:59:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2743E6B00BC; Wed, 22 Jul 2026 22:59:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id E99476B00BA for ; Wed, 22 Jul 2026 22:59:38 -0400 (EDT) Received: from smtpin29.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 5741540376 for ; Thu, 23 Jul 2026 02:59:38 +0000 (UTC) X-FDA: 85018536036.29.3AB3508 Received: from out-183.mta0.migadu.com (out-183.mta0.migadu.com [91.218.175.183]) by imf12.hostedemail.com (Postfix) with ESMTP id 8CB5840005 for ; Thu, 23 Jul 2026 02:59:36 +0000 (UTC) Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=SQEcIDr2; spf=pass (imf12.hostedemail.com: domain of ridong.chen@linux.dev designates 91.218.175.183 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=1784775576; b=Sq9pJvgAuAbErWl8xpw63AcrPVp9TX8OLNq7jEOmaBJwmSeW+2wDlnKD/69vB2RJ0YjQyn ThYT8kEEJipHkB/yckD38HN6yyShUmtK+h5XIjsaLIjCTavT+laRAhtekj/wdu20m3CiFh JYgk00YnXatKEHnszGJQrCXeMg4kAzA= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=SQEcIDr2; spf=pass (imf12.hostedemail.com: domain of ridong.chen@linux.dev designates 91.218.175.183 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=1784775576; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Z8OTpiatQBHFhVb1kcbCtXbO04T0mIjzVEpsj33f5I8=; b=6xGKh3SO+dCrT9wkBq8JtlSsAFyYhtAWb17DzvKU9sCtjbGfYRE1xVVbAxSh26m6O9ftpI 0uUN20Y2vxqHejWvj+DmotvSp3Hvm2pSnQwxFsI8KJEKDTmNVn/ABDYS+PhJXLtcrB6jhv cr6lacQo8WqLAzwZipn/dYj6iuwhndg= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1784775574; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Z8OTpiatQBHFhVb1kcbCtXbO04T0mIjzVEpsj33f5I8=; b=SQEcIDr2tw82PVukVDpkp/Udjvjce6EtsKMOY+rD1choFe5zG8AMa9uPXyGTujI7GyimE0 zWgRQLzJkCQL4sc59iUPNdKFMOrAi9rGiiIVEIp7O+pl4ZlC0t6ixczeZXmcKnwoD1jEOB xBeJ1h+TgFRmmV58WTgs2bIwHG3nJ1Q= From: Ridong To: Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Andrew Morton , Chris Li , Kairui Song Cc: Muchun Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Youngjun Park , David Hildenbrand , Qi Zheng , Lorenzo Stoakes , Axel Rasmussen , Yuanchu Xie , Wei Xu , Davidlohr Bueso , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Song Hu , Ridong Chen , Ridong Chen , stable@vger.kernel.org Subject: [PATCH -v3 2/2] mm: vmscan: fix node reclaim ignoring swappiness parameter Date: Thu, 23 Jul 2026 10:58:58 +0800 Message-Id: <20260723025858.1956584-3-ridong.chen@linux.dev> In-Reply-To: <20260723025858.1956584-1-ridong.chen@linux.dev> References: <20260723025858.1956584-1-ridong.chen@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 8CB5840005 X-Stat-Signature: r7cj9yaa163rda7o5jqogfyp9pjgrusa X-Rspam-User: X-HE-Tag: 1784775576-189518 X-HE-Meta: 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 A9FKwURF zlUxGT8+9frrcrBST3z7Mlp32ezvwnuJiy4mIFa8q2qcVLWowspiObNIE1XbllWzRNbjPN9Hq3x9COks535s3srVTUknaTiGmrRFy+HWzSKDwX3IRFeKn8ADz3thvVQNBs2EE4yyPfb4VgxryDnEoK+nV4jLp0Z8bKkC66W2JRgP9C1SWcY/MWmrf9Ma2Ovqy4fYsqRIbKqzdOe4yXUwEw2NA2Vs6+O0TuKfOJrLymrE/gziy51e6O3r/HC8SyMkpwTQ9HTtoAQWQt0vyqvBjb7jZqqjAG0X8Fh5SHRLy7yG/xZNW8Uhzr4YeSA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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 Cc: stable@vger.kernel.org # 6.17+ Fixes: b980077899ea ("mm: introduce per-node proactive reclaim interface") Acked-by: Johannes Weiner Reviewed-by: Barry Song Acked-by: Qi Zheng Tested-by: Song Hu Reviewed-by: Song Hu Signed-off-by: Ridong Chen --- mm/vmscan.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 06e103f9781e..155167b3614b 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -199,6 +199,13 @@ struct scan_control { */ int vm_swappiness = 60; +static int sc_swappiness(struct scan_control *sc, struct mem_cgroup *memcg) +{ + if (sc->proactive && sc->proactive_swappiness) + return *sc->proactive_swappiness; + return mem_cgroup_swappiness(memcg); +} + #ifdef CONFIG_MEMCG /* Returns true for reclaim through cgroup limits or cgroup interfaces. */ @@ -239,13 +246,6 @@ static bool writeback_throttling_sane(struct scan_control *sc) #endif return false; } - -static int sc_swappiness(struct scan_control *sc, struct mem_cgroup *memcg) -{ - if (sc->proactive && sc->proactive_swappiness) - return *sc->proactive_swappiness; - return mem_cgroup_swappiness(memcg); -} #else static bool cgroup_reclaim(struct scan_control *sc) { @@ -261,11 +261,6 @@ static bool writeback_throttling_sane(struct scan_control *sc) { return true; } - -static int sc_swappiness(struct scan_control *sc, struct mem_cgroup *memcg) -{ - return READ_ONCE(vm_swappiness); -} #endif static void set_task_reclaim_state(struct task_struct *task, -- 2.34.1