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5y03yVLhZABFrKxPiedoWW/TSPLMWZFqtpM/QXNewnH2O5MKcMy4stptRNn1zMnOZWzL7WXs773 jziY4sgJsQEyjxKxAle+0gTAaO/g8/6jdCYyTjtsCzuavyZVWhN+SGuPrfQzTVH4QW8+BybqkZ0 vrSAuG7SBAErI2iUjOj9/9f14bG+mfbCuQrWPpf0H1HB8Zhsz0MgctTrLwSlFvrbghPvKS5zdjw Z9ZaC00cy9I3cwCeIR2weriMTIwksU4kTJteAcKqllWC56lGBYc= X-Proofpoint-ORIG-GUID: hVbPXHv0_SekAZQqxyqoleiO4qcmtTtn X-Proofpoint-GUID: hVbPXHv0_SekAZQqxyqoleiO4qcmtTtn X-Authority-Analysis: v=2.4 cv=SJ1PlevH c=1 sm=1 tr=0 ts=6902bb35 b=1 cx=c_pps a=e1sVV491RgrpLwSTMOnk8w==:117 a=e1sVV491RgrpLwSTMOnk8w==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=xqWC_Br6kY4A:10 a=kj9zAlcOel0A:10 a=x6icFKpwvdMA:10 a=GoEa3M9JfhUA:10 a=VkNPw1HP01LnGYTKEx00:22 a=pZ1mN9JGy3zALVz29ZkA:9 a=CjuIK1q_8ugA:10 cc=ntf awl=host:13657 On Wed, Oct 29, 2025 at 07:45:32PM +0100, Andrey Ryabinin wrote: > > > On 10/27/25 1:28 PM, Harry Yoo wrote: > > > > > +#ifdef CONFIG_SLAB_OBJ_EXT > > + > > +/* > > + * Check if memory cgroup or memory allocation profiling is enabled. > > + * If enabled, SLUB tries to reduce memory overhead of accounting > > + * slab objects. If neither is enabled when this function is called, > > + * the optimization is simply skipped to avoid affecting caches that do not > > + * need slabobj_ext metadata. > > + * > > + * However, this may disable optimization when memory cgroup or memory > > + * allocation profiling is used, but slabs are created too early > > + * even before those subsystems are initialized. > > + */ > > +static inline bool need_slab_obj_exts(struct kmem_cache *s) > > +{ > > + if (!mem_cgroup_disabled() && (s->flags & SLAB_ACCOUNT)) > > Shouldn't this be !memcg_kmem_online() check? > In case of disabled kmem accounting via 'cgroup.memory=nokmem' Good catch. Will fix, thanks! > > + return true; > > + > > + if (mem_alloc_profiling_enabled()) > > + return true; > > + > > + return false; > > +} > > + -- Cheers, Harry / Hyeonggon