On Mon 06-12-21 16:19:12, Kirill Tkhai wrote: > On 06.12.2021 13:45, David Hildenbrand wrote: > >> This doesn't seen complete. Slab shrinkers are used in the reclaim > >> context. Previously offline nodes could be onlined later and this would > >> lead to NULL ptr because there is no hook to allocate new shrinker > >> infos. This would be also really impractical because this would have to > >> update all existing memcgs... > > > > Instead of going through the trouble of updating... > > > > ... maybe just keep for_each_node() and check if the target node is > > offline. If it's offline, just allocate from the first online node. > > After all, we're not using __GFP_THISNODE, so there are no guarantees > > either way ... > > Hm, can't we add shrinker maps allocation to __try_online_node() in addition > to this patch? Either that or through hotplug notifier (which would be a better solution). But allocating a new shrinker map for each memcg would have to be done as has been mentioned earlier. -- Michal Hocko SUSE Labs
