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=1792706591; b=qcrUCcUbDydYzzW4tJyS1bAxr+wTkGR7YH6Ffnmmp1Me2P1xgJmZv0/z9ZfzaPLa7q4v uNemu+Ct7gpe61ojz2vYeUeV2NLIEsiuX15582twjf6G1nyk1JZER+HoEmks7vNzZR2Rw j6MpgiCfOSnAR2oo4tIBfTnfiCKmV6kcworfi+g6r9QanfuqzHxPuewpdff0NN5Kx1Jht EAdRGSLLc2veM8a0YwX0EJOCVetqTRPM+ZSEmqtzwTEi20YmMcCS7IUzxk0RAIqRg5cGw 13VZDXGkB9cQqlYCYnNMZ7phGaCSe+OfPS8gs7CRTWW9CWdaJPvdydeavakQnliou8A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792706591; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-Id:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=6rnjSAKXETk7IX9Iz0xmxItZgkiiI1JWLFVu97pY++w=; b=tlEmPwCsMDaNfZypAyh2i5alFqYlIWeKc52dBWqNhtLh44l0sm7k6GH7u1zh+vhNOqcL 0r+EfOpXGe9IaZvF3VV6xlXYtuSMH9nHhiKZHvm0mhq7u4IFvM9BFfdf/V/bQavFf68vs iL42PVnORcIxkgq+zqk5NVoNLQeJW0cvx4iLShuWeH7EKGScqKgmjv/PTs7ceVWy3m2/g q9KrUtram1HXlnepOnbAWdacZ5e07Ziry2MbUxwdUTIVuljALj3dqgOpptPkXSnXE3JBp SzpznhBjjGrOetaIrNTVyBXbu7ZnjwHFqwkiK+9IttCr9mmEjA625KZc0b64sbMLsLQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="j2p2p/pm"; 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 AE8BA606A321 for ; Thu, 22 Oct 2026 22:03:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=j2p2p/pm Received: by smtp.kernel.org (Postfix) with ESMTPSA id ABC181F01829; Thu, 22 Oct 2026 22:03:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792706590; bh=6rnjSAKXETk7IX9Iz0xmxItZgkiiI1JWLFVu97pY++w=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=j2p2p/pmAqoVZ9r4zJMNX8O3DdOIzV9h7PhopbCDJwq1qoaD4iCS+CfXSKD3vtVTj JceEjLIXTrqQwfGz7D6OV2HQLza5sBt/admhX8WvGgvwRKU5sfwq0TXG/vAr/IDt4W WOwwwb6vKeOL2lM3wnKJOsJg3NKKVA9a8g1n1nhlrcufg/HWcggaQYwJBbVOPimOXT YmwqVVcfqhYAYqFEFRHuQboNPPy+//tTTii//TlKPYnsD6aUlQ6wRqF0b/CmIa2Xc/ NlyVIsNLZK/5GrFzcaKzJpGLhPnd88AjqbVdrW81DqoaV+NlP9juzpINfC0V2z2U/Z c7y/W0QErFFQA== From: "Barry Song (Xiaomi)" To: akpm@linux-foundation.org, linux-mm@kvack.org Cc: hui.zhu@linux.dev, axelrasmussen@google.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, david@kernel.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, ljs@kernel.org, mhocko@kernel.org, qi.zheng@linux.dev, ryncsn@gmail.com, shakeel.butt@linux.dev, weixugc@google.com, yuanchu@google.com, zhuhui@kylinos.cn, baoquan.he@linux.dev, liuxiang.277@bytedance.com, wangzicheng@honor.com, lianux.mm@gmail.com, kasong@tencent.com, liam@infradead.org, surenb@google.com, mhocko@suse.com, rppt@kernel.org, zhangbo56@xiaomi.com, lyugaofei@xiaomi.com, ridong.chen@linux.dev, kunwu.chan@gmail.com Subject: [RFC PATCH v5 11/14] mm/mglru: Reduce LRU lock contention by shrinking folio batches in inc_min_seq Date: Fri, 23 Oct 2026 06:02:00 +0800 Message-Id: <20261022220203.91911-12-baohua@kernel.org> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-Reply-To: <20261022220203.91911-1-baohua@kernel.org> References: <20261022220203.91911-1-baohua@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Reduce the number of folios moved from the oldest generation to the second-oldest generation in each batch. This shortens the time the lruvec lock is held, allowing concurrent LRU operations to make progress and significantly reducing LRU lock contention. Signed-off-by: Barry Song (Xiaomi) --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index e8eeeeb76282..555359cc0368 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4051,7 +4051,7 @@ static inline void flush_lru_batch(struct list_head *head, struct list_head **ba static bool inc_min_seq(struct lruvec *lruvec, int type, int swappiness) { int zone; - int remaining = MAX_LRU_BATCH; + int remaining = MIN_LRU_BATCH; struct lru_gen_folio *lrugen = &lruvec->lrugen; int hist = lru_hist_from_seq(lrugen->min_seq[type]); int new_gen, old_gen = lru_gen_from_seq(lrugen->min_seq[type]); -- 2.34.1