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To: Harry Yoo Cc: bpf , linux-mm , Vlastimil Babka , Shakeel Butt , Michal Hocko , Sebastian Sewior , Andrii Nakryiko , Kumar Kartikeya Dwivedi , Andrew Morton , Peter Zijlstra , Steven Rostedt , Johannes Weiner Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 0EEB0140012 X-Stat-Signature: mzsrgegcy6dy34bw51ocoyz85uzf9dsx X-Rspam-User: X-HE-Tag: 1757984415-591956 X-HE-Meta: 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 SvqrJveB XCN848SW61YSDwrJHCjgzfO8x2CRQ+5hU0kcnf0YMHSRAMDo0mgVEEbuaJJhBomV1CMC97bFt7Dg3ptNOzPXyJiBOZY00VX9TlH9BFoEn6t9+9e3N5Qrl79XZWxIo2EFw26+ynmmgc+OV6omMd3wAdgUa6iabdZ2uDvASMTy5+i1jmPYEkKxukHYEdUuoHkcynbHUAMYt8KpccStIIzhLEGaKu2vIONX9MLCbQwykagw3bOLY2nGfsuIVgYlwDgdrqHC41R/Z2qYk9eUd1eeaBxrqAF4IfBzbK0GR7Wknmql9pN8A+9yYfGm97q1/b7pe97DdJodSMmY4Kunyg7pI28phWJLmrLe5vX0cLtXlrh9OpiScWhnVeQJfkRQivVfMPPLtWXUFnTHjEPbCTi39CPP66+SkgwHNBEEbZRIk8dhX3a/lWMSgfOKtThSe4NLsqk7uEhigYOphxQs= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Sep 15, 2025 at 5:53=E2=80=AFAM Harry Yoo wr= ote: > > > if (unlikely(!node_match(slab, node))) { > > /* > > * same as above but node_match() being false already > > - * implies node !=3D NUMA_NO_NODE > > + * implies node !=3D NUMA_NO_NODE. > > + * Reentrant slub cannot take locks necessary to > > + * deactivate_slab, hence ignore node preference. > > nit: the comment is obsolte? Ohh. Sorry. I clearly remember fixing this comment per your feedback. Not sure how I lost this hunk. > Per previous discussion there were two points. > Maybe something like this? > > /* > * We don't strictly honor pfmemalloc and NUMA preferences when > * !allow_spin because: > * > * 1. Most kmalloc() users allocate objects on the local node, > * so kmalloc_nolock() tries not to interfere with them by > * deactivating the cpu slab. > * > * 2. Deactivating due to NUMA or pfmemalloc mismatch may cause > * unnecessary slab allocations even when n->partial list is not empty= . > */ > > ...or if you don't feel like it's not worth documenting, > just removing the misleading comment is fine. The above reads great to me. Will send a follow up patch in a minute to fold in or keep it separate.