On Mon 22-03-21 15:42:27, Michal Hocko wrote: [...] > Besides that the changelog doesn't really say anything about changed > user visible behavior change. Now if somebody decreases the GB huge pool > from the userspace the real effect on the freed up memory will be > postponed to some later time. That "later" is unpredictable as it > depends on WQ utilization. We definitely need some sort of > wait_for_inflight pages. One way to do that would be to have a dedicated > WQ and schedule a sync work item after the pool has been shrunk and wait > for that item. Scratch that. It is not really clear from the patch context but after looking at the resulting code set_max_huge_pages will use the blockable update_and_free_page so we should be fine. Sorry about the noise! -- Michal Hocko SUSE Labs
