On Tue, Jun 01, 2021 at 11:47:13AM +0200, Michal Hocko wrote: > While you are touching this and want to drill all the way down then it > would be reasonable to drop pgdat resize locks as well. > It is only used in the early boot code and we have one executing thread > context per numa node during the deferred initialization. I haven't > checked all potential side effects the lock might have but it sounds > like there is quite some clean up potential over there. I am not sure about that. True is that deferred_init_memmap() gets executed on numa-thread so it's not a problem for itself, but we also have deferred_grow_zone(). It might be that while deferred_init_memmap() is running, we also have calls to deferred_grow_zone() for the same node and that would cause some trouble wrt. first_deferred_pfn. I need to double check it, but IIRC, that is the case. -- Oscar Salvador SUSE L3
