As you're probably aware, my plan is to get rid of SLOB and SLAB, leaving only SLUB going forward. The removal of SLOB seems to be going well, there were no objections to the deprecation and I've posted v1 of the removal itself [1] so it could be in -next soon. The immediate benefit of that is that we can allow kfree() (and kfree_rcu()) to free objects from kmem_cache_alloc() - something that IIRC at least xfs people wanted in the past, and SLOB was incompatible with that. For SLAB removal I haven't yet heard any objections (but also didn't deprecate it yet) but if there are any users due to particular workloads doing better with SLAB than SLUB, we can discuss why those would regress and what can be done about that in SLUB. Once we have just one slab allocator in the kernel, we can take a closer look at what the users are missing from it that forces them to create own allocators (e.g. BPF), and could be considered to be added as a generic implementation to SLUB. Thanks, Vlastimil [1] https://lore.kernel.org/all/20230310103210.22372-1-vbabka@xxxxxxx/
