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=1792706544; b=CcsST/ZA0kMZsvjp2cRiiNdJ0sEmYS/k8AAxtToUb4nSJxiIm+XSxLlHuESFvCFwN2W0 4JTPDTh7qFc2XX2NBWQiQofdeze4+LRAHmdGsiyntovHUwlBwv8LtWbd9n+ExXb8sGyTa l3Ka4edBS2/+6mqnuIbWGgAJixTP9Zeu8vPWQTl+yz3OzWyogf3tNhpAUAFyeuXq9cYYc BXOy1Zzv/8WUG4RfpIDsWLWtf7NldXX+Y5dZENuk9BdqI9osWFjk3B370hi1IZxoreSAP Ilf7yTfW0qGOjCo5C8v3Kde/sJ2qlYE534aYCCo0BOHWBjPp20SDz4bB8otRzi2sb/Q== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792706544; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-Id:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=gMfZkTuxTlSsyjGjWesRKoIv1NGikpPcCvSdfeM0NJ4=; b=2zBcGMQUoUN8fDWsCK85IK+gCbkokN6//p+/n2gvonHXORgr6dRqWHKQYfoE5dccCIZW srXgYWmQqVU/bjDOTjrVypw8IBopQExO69trtDIUkmB6cc8xZ1XiVwPPxQpOy128+QPy1 pk/J3XH/ua0TRJjqw7ZlPkYFc2Pcw0PixLTyurmr1mc1pNua/ZbVnxkhU0CcOtn/h9Iva zYEizsE5tvyBNQAFA8gvV7Vut04PNsHHt30290dGUhhWgJM84ZGlFOiEo5ChTtqpIIAdM FKxEg6gA+7izKINhQ0HM72LKaP5T7M7xFkPDy3r07GNfXFsBy8KycsFPAFtOcBgSBIA== 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=QalWKvm9; 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 A7F7A606A31A for ; Thu, 22 Oct 2026 22:02:23 +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=QalWKvm9 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 55F4E1F01829; Thu, 22 Oct 2026 22:02:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792706543; bh=gMfZkTuxTlSsyjGjWesRKoIv1NGikpPcCvSdfeM0NJ4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=QalWKvm9yD1uCCEOxwkWey6CoBh/gYh5acwDeOHUfnTQ7/a0vUVmFkvY5YJqvPjXW aAgY1vj5U5/2x3/Skt7zY1VWidrutMaLTlfd1Cma5Fl77gRlmFuKM6A9dkP6CLGkhK bSZPuu2rrY2Y9SgASUkV+/6SBBEWZxTbNVVuw2YLntddNjrDshQ3jmuDTBQMAB9efQ /s6limoyz5jeP0AWECMIvqTnWQ+OCEuMjQPFC3lVkCxqGbCMK7t4RxjJzn61VpVSJW FTQ84P0+/uL8G1/OAqOLx+dmbHf8vaFMGq4S/Te5jPxcweB093N0PDvTok1EZIKPcO 2wuqwGj4UOCHg== 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 02/14] mm/mglru: extract lruvec_populated_min_seq() helper Date: Fri, 23 Oct 2026 06:01:51 +0800 Message-Id: <20261022220203.91911-3-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 From: Kairui Song The search for the oldest populated generation of a type, previously embedded in try_to_inc_min_seq(), is extracted into the new lruvec_populated_min_seq() helper. It returns the oldest populated seq of a given type, bounded by the given max_seq so the search never goes beyond it. No functional change. Signed-off-by: Kairui Song Signed-off-by: Barry Song (Xiaomi) --- mm/vmscan.c | 43 +++++++++++++++++++++++++++++-------------- 1 file changed, 29 insertions(+), 14 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 3be0d6c04a82..500ef23949fd 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4131,30 +4131,45 @@ static bool inc_min_seq(struct lruvec *lruvec, int type, int swappiness) return true; } +/* Similar to lruvec_evictable_size, return the oldest populated seq of the type */ +static unsigned long lruvec_populated_min_seq(struct lruvec *lruvec, int type, + unsigned long max_seq) +{ + int gen, zone; + unsigned long min_seq; + struct lru_gen_folio *lrugen = &lruvec->lrugen; + + lockdep_assert_held(&lruvec->lru_lock); + + min_seq = READ_ONCE(lrugen->min_seq[type]); + while (min_seq <= max_seq) { + gen = lru_gen_from_seq(min_seq); + for (zone = 0; zone < MAX_NR_ZONES; zone++) { + if (!list_empty(&lrugen->folios[gen][type][zone])) + return min_seq; + } + min_seq++; + } + + return max_seq; +} + static void try_to_inc_min_seq(struct lruvec *lruvec, int swappiness) { - int gen, type, zone; + int type; bool seq_inc_flag = false; struct lru_gen_folio *lrugen = &lruvec->lrugen; DEFINE_MIN_SEQ(lruvec); + unsigned long seq; VM_WARN_ON_ONCE(!seq_is_valid(lruvec)); - /* find the oldest populated generation */ + /* Requires at least MIN_NR_GENS gens for basic functionality */ + seq = lrugen->max_seq - MIN_NR_GENS; for_each_evictable_type(type, swappiness) { - while (min_seq[type] + MIN_NR_GENS <= lrugen->max_seq) { - gen = lru_gen_from_seq(min_seq[type]); - - for (zone = 0; zone < MAX_NR_ZONES; zone++) { - if (!list_empty(&lrugen->folios[gen][type][zone])) - goto next; - } - - min_seq[type]++; + min_seq[type] = lruvec_populated_min_seq(lruvec, type, seq + 1); + if (min_seq[type] > lrugen->min_seq[type]) seq_inc_flag = true; - } -next: - ; } /* -- 2.34.1