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[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-cxl@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