mm, mempolicy: migrate_to_node should only migrate to node
migrate_to_node() is intended to migrate a page from one source node to
a target node.
Today, migrate_to_node() could end up migrating to any node, not only
the target node. This is because the page migration allocator,
new_node_page() does not pass __GFP_THISNODE to
alloc_pages_exact_node(). This causes the target node to be preferred
but allows fallback to any other node in order of affinity.
Prevent this by allocating with __GFP_THISNODE. If memory is not
available, -ENOMEM will be returned as appropriate.
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 4721046..69d05ac 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -945,7 +945,8 @@
return alloc_huge_page_node(page_hstate(compound_head(page)),
node);
else
- return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE, 0);
+ return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE |
+ __GFP_THISNODE, 0);
}
/*