ksm: cond_resched in unstable tree
KSM needs a cond_resched() for CONFIG_PREEMPT_NONE, in its unbounded
search of the unstable tree. The stable tree cases already have one,
and originally there was one down inside get_user_pages();
but I missed it when I converted to follow_page() instead.
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Acked-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/ksm.c b/mm/ksm.c
index bef1af4..5575f86 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1012,6 +1012,7 @@
struct rmap_item *tree_rmap_item;
int ret;
+ cond_resched();
tree_rmap_item = rb_entry(*new, struct rmap_item, node);
page2[0] = get_mergeable_page(tree_rmap_item);
if (!page2[0])