From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt1-f179.google.com (mail-qt1-f179.google.com [209.85.160.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 07171311C09 for ; Fri, 9 Jan 2026 16:08:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767974912; cv=none; b=MEYjKZ2PDsWujhSVzg6c2EnWA56Nv1vzXUh4r+pmPBuUJ1o6SlEhf7eAQ0gQ1PMZEtSz2nXvHgp3NYw0vO7lY6M62iA6K47gEi4GjeU8Gocqcg/OAcDZ8vmt7k///ijAhZTd5T24wYRvTf07qCMq/afqNhbEJ3wrfPTeAVljHsw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767974912; c=relaxed/simple; bh=dDdBteoNYUbTfJwW87hxXDzBER4RJ3dbkkyRnQ02yRQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rngNrdqmNxgIz0M/J0DHq5ZHCCxFyStBQ8rZVXlURiOD/4MCeUEpjV7rxhJK5X0/quoLC32UOQl+5WYhwL6FQ9FW6VGjOZ0+E5UML1qiIH80JZzXYGtWFaaLPhxA/Q1Wb6+z/xxfyfgMFyh/thtxUHXWQ0B6sRVhBfBwMLJuULk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=gourry.net; spf=pass smtp.mailfrom=gourry.net; dkim=pass (2048-bit key) header.d=gourry.net header.i=@gourry.net header.b=R5ww8e+U; arc=none smtp.client-ip=209.85.160.179 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=gourry.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gourry.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gourry.net header.i=@gourry.net header.b="R5ww8e+U" Received: by mail-qt1-f179.google.com with SMTP id d75a77b69052e-4ee1939e70bso44918821cf.3 for ; Fri, 09 Jan 2026 08:08:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gourry.net; s=google; t=1767974908; x=1768579708; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=V4vHEUNRYMXphH1rfrlOiSS0TJwDxNN0hMRXL63E6jo=; b=R5ww8e+UZ+9lm7KN5g63LME5bLx8Y5/4fUTKwLy+EED6VZhApFnMLxtn9wbi7qzSau EFPBKB3aoPjkF+zNjPsTyl2vaZ7hXh7gObBZZqgEAIoW3XaumXpa525HRGyos07tPEve hbBQTaYhRvcFLEfkOEm7zqoX2EOZBaXFwfnWlwldbT0rwl2NY3TkUYagcWVm0bKvv4i6 z7CtBhiGsOKjgMRBy+unfOYQRGLcr7WXuND0Ln4aByAPMRln/8dYogt4SDe266IRf/2p XgswHnnpv2WF03zbzqr558zx6YZEsFcLv/4swSgap2Y1X/aViMxEAYH0zW9Ivod8mbu7 w3+Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767974908; x=1768579708; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=V4vHEUNRYMXphH1rfrlOiSS0TJwDxNN0hMRXL63E6jo=; b=TvtT4tvi1Lt9vxgtwaYVqyOTLmN7XXoEy9eU33G2zQTRljxenamH/DmZOn0t1K8XBW 87l05wLt/8fs+C3mbg8P2oTlAyQ+ybcSGuwdu619iOfDXpY30Ge+w2aRUUmtkC+5uYs/ LLJ169Cl7+xuGyocvN0hwtHxGE4+okYsdyg80e5/m+0IAItPAcxQZ5pCMyuN/FYvp+DL Zt5Ix2hesagL5YBPXGSd0VaKQtBY+WDYWYwdt+7R4PXBNbfew8G0F39Df52o52R9No0e +djbAABzvvm8wPdAZOiM+yqtFGTo5PJRqcQi822HRgPp4NjdYAPg9r+aLnqeGVrN3BBl 2toQ== X-Forwarded-Encrypted: i=1; AJvYcCULpazDV3k/HO4xrJBg2mXYZ5xQaH4CMa6j1Xcm+Hp7YlWYGw5R+9Vu00nJ/6IuRM0uFtgVc+UMmwLjNeQ=@vger.kernel.org X-Gm-Message-State: AOJu0YyQkCOwbgoSNH7r65CoJTH9zJDwXAmixD4rKWVzIH4txaZF5xZd aKHfB5xcenRcw5D4Q8NPpIXwYq80kGFCl/uLFfuwOadEsErCgI5lfVT4nH+C7uMRXOM= X-Gm-Gg: AY/fxX4fJfY8l766QOMqlTciTPnY+ag6znDBAUbUFFdP83MdIUsVDDgoTjbqxa2p3l2 q5czrY3h8wMJmS4IgPHvmMuYPZ6mOq/vdhFXg00/uswC1+C4EfopRk+I4z1lg5cdLfYCjigpj6s zJjs4R/9y2NjUXugPOIFQpqbxC48PS9qYXs1gkL6C7XOPMFBMxmg7hBcTgWyUxTUkLgDDbM0t7E /DY5D+q/lS2SbN8D4AZjKTLNoxHetwwjGerzTN7TgwSThT/EBfNHCrWzJlpZ0N9e0ZUwEF8YqJF nKxE0c91Y7hPwZ9Gopm0RHXdt7AMPQqJSTq89b9vsY9ALh2/fe6cfXEU/kNandz/RLTIn0hMDK5 IDwvkKQryy/vujmHBcic+H7ylxCoG3mrbUZ29UeY9NQnAl5uuY390zJnYE2L/R6+SM/ibo/GtyH LbvvW5WCWGXbAC7JPhkcuZenMQiCjOXG+65QMtLj/9sLuMHOxoZSsRLsrhCV5D5tM/2dnArw== X-Google-Smtp-Source: AGHT+IEdvXZpwW/0Rj/zKD9Q0FT8JfSOnFbEdErwx/lCsZ0mgwmxjheOk0MqApSu4txhmwbpb7cX6Q== X-Received: by 2002:ac8:580f:0:b0:4ee:1db1:a60f with SMTP id d75a77b69052e-4ffb47d6537mr154025831cf.16.1767974908465; Fri, 09 Jan 2026 08:08:28 -0800 (PST) Received: from gourry-fedora-PF4VCD3F (pool-96-255-20-138.washdc.ftas.verizon.net. [96.255.20.138]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-4ffb75d7916sm57189031cf.7.2026.01.09.08.08.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 09 Jan 2026 08:08:27 -0800 (PST) Date: Fri, 9 Jan 2026 11:07:52 -0500 From: Gregory Price To: Akinobu Mita Cc: linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, hannes@cmpxchg.org, david@kernel.org, mhocko@kernel.org, zhengqi.arch@bytedance.com, shakeel.butt@linux.dev, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, bingjiao@google.com Subject: Re: [PATCH v3 3/3] mm/vmscan: don't demote if there is not enough free memory in the lower memory tier Message-ID: References: <20260108101535.50696-1-akinobu.mita@gmail.com> <20260108101535.50696-4-akinobu.mita@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260108101535.50696-4-akinobu.mita@gmail.com> > + for_each_node_mask(nid, allowed_mask) { > + int z; > + struct zone *zone; > + struct pglist_data *pgdat = NODE_DATA(nid); > + > + for_each_managed_zone_pgdat(zone, pgdat, z, MAX_NR_ZONES - 1) { > + if (zone_watermark_ok(zone, 0, min_wmark_pages(zone), > + ZONE_MOVABLE, 0)) Why does this only check zone movable? Also, would this also limit pressure-signal to invoke reclaim when there is still swap space available? Should demotion not be a pressure source for triggering harder reclaim? ~Gregory