On Tue 16-02-21 12:34:41, Muchun Song wrote: > On Tue, Feb 16, 2021 at 3:39 AM Michal Hocko <mhocko@xxxxxxxx> wrote: [...] > > > Using GFP_KERNEL will also use the current task cpuset to allocate > > > memory. Do we have an interface to ignore current task cpuset？If not, > > > WQ may be the only option and it also will not limit the context of > > > put_page. Right? > > > > Well, GFP_KERNEL is constrained to the task cpuset only if the said > > cpuset is hardwalled IIRC. But I do not see why this is a problem. > > I mean that if there are more than one node in the system, > but the current task cpuset only allows one node. How would that cpuset get a huge pages from a node which is not part of the cpuset? Well, that would be possible if the cpuset was dynamic but I am not sure that such a configuration would be very sensible along with hardwall setup. > If current > node has no memory and other nodes have enough memory. > We can fail to allocate vmemmap pages. But actually it is > suitable to allocate vmemmap pages from other nodes. > Right? Falling back to a different node would be very suboptimal because then you would have vmemmap back by remote pages. We do not want that. -- Michal Hocko SUSE Labs
