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From: Muchun Song In-Reply-To: <20260520053123.2709959-2-shakeel.butt@linux.dev> Date: Wed, 20 May 2026 14:13:47 +0800 Cc: Andrew Morton , Johannes Weiner , Michal Hocko , Roman Gushchin , Qi Zheng , Alexandre Ghiti , Joshua Hahn , Harry Yoo , Meta kernel team , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel test robot Content-Transfer-Encoding: 7bit Message-Id: <0B4974B5-FB9B-47CD-956A-B13BCF278163@linux.dev> References: <20260520053123.2709959-1-shakeel.butt@linux.dev> <20260520053123.2709959-2-shakeel.butt@linux.dev> To: Shakeel Butt X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 42E271C0006 X-Rspam-User: X-Stat-Signature: czx6rf8rx3okg36wjxxe9fdbns78wyg9 X-HE-Tag: 1779257690-499829 X-HE-Meta: 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 DdjSDPOX QUj9PCC2/dsvJEYcob9WQnWI5eR+oWSIbtseGIw3SSf1pa9fV+SaPNywBOa9tzRg95O+o14AvCnfJnYwiwzX8r3Z8cQ1hifkk9JU26WABNd/BEtROaSj6DEhHjUN0DFUIuTTw4Chm7jHOjVkACZGyi6NWdfz/0mbvBEBOVgH/YyJjvJldu2V3TcPpCT3BPhYU/X0nP6yjN9zXuinhqm2NafHilDsRPmS4LQVM1ypVTPa36QXaKxle4/XHvF8a9zIg1in2LOoN1xxNShPZI+n13nsBW7FuqZugvo0U2va85wArWeVAQdSKu7kIT5EoEQBcLzapN7tpmCeDqiRABCgdHu7oIHu4704a0CU5nPgKvVYEpV81z++Nm3nNl5YhC8QHnaXKRfw+6/GYq51Yjm8w7BbmtZ9NqsKIIog7 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On May 20, 2026, at 13:31, Shakeel Butt wrote: > > The struct obj_stock_pcp stores a pointer to pglist_data for the slab > stats cached on the cpu. On 64-bit machines, this costs 8 bytes. The > pointer is not strictly required: NODE_DATA() can recover it from the > node id. Replace cached_pgdat with int16_t node_id and use NUMA_NO_NODE > as the "no stats cached" sentinel. > > At the moment all the archs limit MAX_NUMNODES to 1024 so int16_t is > plenty; a BUILD_BUG_ON() makes sure we notice if that ever changes. > > Signed-off-by: Shakeel Butt > Tested-by: kernel test robot Acked-by: Muchun Song Thanks.