On 2018/08/16 19:03, Michal Hocko wrote:
> The code is quite subtle and we have a bad history of copying stuff
> without rethinking whether the code still is needed. Which is sad and a
> clear sign that the code is too complex. I cannot say this change
> doesn't have any subtle side effects but it makes the intention clear at
> least so I _think_ it is good to go. If we find some unintended side
> effects we should simply rethink the whole reset zonelist thing.
Does this change affect
/*
* This is not a __GFP_THISNODE allocation, so a truncated nodemask in
* the page allocator means a mempolicy is in effect. Cpuset policy
* is enforced in get_page_from_freelist().
*/
if (oc->nodemask &&
!nodes_subset(node_states[N_MEMORY], *oc->nodemask)) {
oc->totalpages = total_swap_pages;
for_each_node_mask(nid, *oc->nodemask)
oc->totalpages += node_spanned_pages(nid);
return CONSTRAINT_MEMORY_POLICY;
}
in constrained_alloc() called from
/*
* Check if there were limitations on the allocation (only relevant for
* NUMA and memcg) that may require different handling.
*/
constraint = constrained_alloc(oc);
if (constraint != CONSTRAINT_MEMORY_POLICY)
oc->nodemask = NULL;
in out_of_memory() ?
