Commit 4741526b authored by Mel Gorman's avatar Mel Gorman Committed by Linus Torvalds

mm, page_alloc: restore the original nodemask if the fast path allocation failed

The page allocator fast path uses either the requested nodemask or
cpuset_current_mems_allowed if cpusets are enabled.  If the allocation
context allows watermarks to be ignored then it can also ignore memory
policies.  However, on entering the allocator slowpath the nodemask may
still be cpuset_current_mems_allowed and the policies are enforced.
This patch resets the nodemask appropriately before entering the
slowpath.

Link: http://lkml.kernel.org/r/20160504143628.GU2858@techsingularity.netSigned-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarMel Gorman <mgorman@techsingularity.net>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 4e611801
...@@ -3636,6 +3636,12 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, ...@@ -3636,6 +3636,12 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
alloc_mask = memalloc_noio_flags(gfp_mask); alloc_mask = memalloc_noio_flags(gfp_mask);
ac.spread_dirty_pages = false; ac.spread_dirty_pages = false;
/*
* Restore the original nodemask if it was potentially replaced with
* &cpuset_current_mems_allowed to optimize the fast-path attempt.
*/
if (cpusets_enabled())
ac.nodemask = nodemask;
page = __alloc_pages_slowpath(alloc_mask, order, &ac); page = __alloc_pages_slowpath(alloc_mask, order, &ac);
no_zone: no_zone:
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment