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> > > void *kmem_cache_alloc(struct kmem_cache *s, gfp_t flags) __assume_slab_alignment __malloc; > > > +void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > > > + gfp_t gfpflags) __assume_slab_alignment __malloc; > > > > I'm not a big fan of this patch: I don't see why preparing the lru > > infrastructure has to be integrated that deep into the slab code. > > > > Why can't kmem_cache_alloc_lru() be a simple wrapper like (pseudo-code): > > void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > > gfp_t gfpflags) { > > if (necessarily) > > prepare_lru_infra(); > > return kmem_cache_alloc(); > > } > > Hi Roman, > > Actually, it can. But there is going to be some redundant code similar > like memcg_slab_pre_alloc_hook() does to detect the necessity of > prepare_lru_infra() in the new scheme of kmem_cache_alloc_lru(). > I just want to reduce the redundant overhead. Is this about getting a memcg pointer? I doubt it's a good reason to make changes all over the slab code. Another option to consider adding a new gfp flag. Vlastimil, what do you think? Thanks!