From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792832509; b=EyFe+sKU8eLMr/xoLeRHVoAqfOFOrJD5z1LQmKMZtkN+b9bokZlckaFnBrJmfHMhc+5p iISo6oLzVhNBgzdFRlD9Cwd8MntbZTjYZ1lyZRf3SJv37UEgKpb+KY6JIfko5Z/L/TK+w cpH+aP/JVu5+xGmFV1R/t0kMHtegV8mvE4cJ5Oy9zRpTHESHTwPJKDKzJDoIxdxuGf/+x bpLUasz3RfnnYwsdZRgiJZyicNPec5jDPs2RlTJfq1ywUIcAcI+YUISSlZSJBBdOhBwc3 CkEUzywnKWZEF4RAZB2kT5b8CUsWnpeljih6Vhdd9aiJXz5L2Ywnn9YWh1FqMvLTSiA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792832509; h=Received:DKIM-Signature:Date:To:From:Subject:Message-Id; bh=eHjkpEr9oLlcclPn1thOraO4+8omjU4rLZkEzk9l+nE=; b=vgX7zYWQGkZMPENfoQMbjm5D6WGeqkCqPNDV8KqeL5lCgC2dk5CwwRq39EeWDL+wckRv XYwMpyJxxMxcSuhYbZg2u99vFtQRlFPzmn8dMsJejKcyk6LVAIEzAA5D9RANItLsQcKmf Dr+T6/2XXNWVsEuUhzBIx7bP59kGsIWYr3qTZqiUhbCJ2mc2plxzO5bCmrpa6fgt0zVwK SeOaVpaOrBp0QH+4C5iOieOkX3ACPev+BoN1HCHxDaXDBKHGNvgt7NFZgkC/DvenEzOJ7 H+axebypB/zmbmB/7SA6qUgzV6l5EyQJZN4hwAXZiYRQ24LG9VISnsRH2mSXwTj9/og== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linux-foundation.org header.i=@linux-foundation.org header.a=rsa-sha256 header.s=korg header.b=CucWtMqV; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 89CC8606A322; Sat, 24 Oct 2026 09:01:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux-foundation.org header.i=@linux-foundation.org header.a=rsa-sha256 header.s=korg header.b=CucWtMqV Received: by smtp.kernel.org (Postfix) with ESMTPSA id 556541F01825; Sat, 24 Oct 2026 09:01:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1792832509; bh=eHjkpEr9oLlcclPn1thOraO4+8omjU4rLZkEzk9l+nE=; h=Date:To:From:Subject; b=CucWtMqVgipwE1vW2WtIdXEaF/9S6oS2QDjkBa50BLW6k6P/esxGB3guXpfxutXmW aYU930sSzS9yj5plnP3p9TMaWQYrNIFMvbBmDw64SQEgtaNtF8T2BeIORuUGIhe6NC 6bKJMbyuCbwG1Qw2eBtXET4a2qdY1IoPbT8a/L+0= Date: Sat, 24 Oct 2026 02:01:48 -0700 To: mm-commits@vger.kernel.org,yuanchu@google.com,weixugc@google.com,stable@vger.kernel.org,shakeel.butt@linux.dev,roman.gushchin@linux.dev,ridong.chen@linux.dev,qi.zheng@linux.dev,mhocko@kernel.org,ljs@kernel.org,kasong@tencent.com,hannes@cmpxchg.org,david@kernel.org,dave@stgolabs.net,baoquan.he@linux.dev,baolin.wang@linux.alibaba.com,baohua@kernel.org,axelrasmussen@google.com,yanglincheng@kylinos.cn,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-vmscan-dont-count-per-node-proactive-reclaim-as-memory-pressure.patch removed from -mm tree Message-Id: <20261024090149.556541F01825@smtp.kernel.org> X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list The quilt patch titled Subject: mm: vmscan: don't count per-node proactive reclaim as memory pressure has been removed from the -mm tree. Its filename was mm-vmscan-dont-count-per-node-proactive-reclaim-as-memory-pressure.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Vernon Yang Subject: mm: vmscan: don't count per-node proactive reclaim as memory pressure Date: Mon, 12 Oct 2026 10:29:17 +0800 When the cgroup has no memory pressure at all, writing to /sys/devices/system/nodeX/reclaim triggers proactive reclaim on NUMA node, causing increase in the writer cgroup's memory PSI. Due to this reclaim is performed in the context of the write(), accounted as memory pressure on the writer, like commit e22c6ed90aa9 ("mm: memcontrol: don't count limit-setting reclaim as memory pressure"). This is unexpected, the similar scenarios (e.g. senpai) will continue to occur, only this time it is for the /sys/devices/system/nodeX/reclaim knob. The Documentation/ABI/stable/sysfs-devices-node documentation also notes that "This interface is equivalent to the memcg variant." This patch unifies the semantics of the memcg and node interfaces: per-node proactive reclaim is no longer counted as memory pressure, and the per-node proactive reclaim interface no longer produces phantom pressure. I ran demo[1] that performs per-node proactive reclaim 10000 times in qemu, writer cgroup memory.pressure as follows: without patch: some avg10=31.53 avg60=13.42 avg300=3.31 total=10602985 full avg10=31.53 avg60=13.42 avg300=3.31 total=10602985 with patch: some avg10=9.59 avg60=3.41 avg300=0.81 total=2686221 full avg10=9.59 avg60=3.41 avg300=0.81 total=2686221 Link: https://lore.kernel.org/20261012022917.1102467-1-vernon2gm@gmail.com Link: https://github.com/vernon2gh/app_and_module/tree/main/reclaim_node_psi [1] Fixes: b980077899ea ("mm: introduce per-node proactive reclaim interface") Signed-off-by: Vernon Yang Signed-off-by: Andrew Morton Reviewed-by: Baolin Wang Reviewed-by: Barry Song Reviewed-by: Ridong Chen Acked-by: Davidlohr Bueso Cc: David Hildenbrand Cc: Kairui Song Cc: Qi Zheng Cc: Shakeel Butt Cc: Axel Rasmussen Cc: Yuanchu Xie Cc: Wei Xu Cc: Baoquan He Cc: Johannes Weiner Cc: Michal Hocko Cc: Lorenzo Stoakes Cc: Roman Gushchin Cc: --- mm/vmscan.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/mm/vmscan.c~mm-vmscan-dont-count-per-node-proactive-reclaim-as-memory-pressure +++ a/mm/vmscan.c @@ -7998,7 +7998,8 @@ static unsigned long __node_reclaim(stru sc->gfp_mask); cond_resched(); - psi_memstall_enter(&pflags); + if (!sc->proactive) + psi_memstall_enter(&pflags); delayacct_freepages_start(); fs_reclaim_acquire(sc->gfp_mask); /* @@ -8015,7 +8016,8 @@ static unsigned long __node_reclaim(stru memalloc_noreclaim_restore(noreclaim_flag); fs_reclaim_release(sc->gfp_mask); delayacct_freepages_end(); - psi_memstall_leave(&pflags); + if (!sc->proactive) + psi_memstall_leave(&pflags); trace_mm_vmscan_node_reclaim_end(sc->nr_reclaimed, NULL); _ Patches currently in -mm which might be from yanglincheng@kylinos.cn are