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From: Qi Zheng In-Reply-To: <20260522011908.1669332-2-shakeel.butt@linux.dev> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Queue-Id: C33B4140005 X-Rspamd-Server: rspam03 X-Stat-Signature: kzay9dwpzz6gwt5jp8cfm1domkjpgdhb X-HE-Tag: 1779416867-987896 X-HE-Meta: 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 v6wbDhF0 TlbqFC/NyWC2Tb3D2r1r432gwSswX9KItA28xQtFy7AQA5kLxiJBxnK1P9QQYhQl1uZQAhharUtACOA3CaCWoLi+AIzpvCx+iCFGY1HbqkXfWTWvpSJM7/S4OynSdo91yOZDVf/DGj+R/bxFfmy+3CpbF4N6xRTdhDNWhzvewkrn8GcWYoCNkJfEOwNELWP/+miK6adohjCBmo25N85/A7I2nrLY1UklrWYqoAbz2tsfKhWh9j3IxDBqtcGlfZ5bUSr2EYaOWN0yJGQzRyC5qZQ/0gqOrBukunnQZjIlMHj4mC03m+nKfRWqG9Da0vl4PtcBQ4PRYocQ5wB2+9dRXrlr6e0oG7C0DI0TDmcYgJEtJ9IPJ/Of6uupnew== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 5/22/26 9:19 AM, 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. > > Fixes: 01b9da291c49 ("mm: memcontrol: convert objcg to be per-memcg per-node type") > Tested-by: kernel test robot > Signed-off-by: Shakeel Butt > Acked-by: Muchun Song > Reviewed-by: Harry Yoo (Oracle) > --- > > Changes since v1: > - Added tags in the commit message > > mm/memcontrol.c | 26 +++++++++++++++++++------- > 1 file changed, 19 insertions(+), 7 deletions(-) > Acked-by: Qi Zheng Thanks!