From: Li RongQing <roy.qing.li@gmail.com>
Date: Tue, 26 Jul 2016 22:26:53 +0000 (-0700)
Subject: mm: memcontrol: remove BUG_ON in uncharge_list
X-Git-Tag: v4.8-rc1~147^2~4
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=17408d785a2eda374b7e673afe20309687a63f08;p=linux.git

mm: memcontrol: remove BUG_ON in uncharge_list

When calling uncharge_list, if a page is transparent huge we don't need
to BUG_ON about non-transparent huge, since nobody should be able to see
the page at this stage and this page cannot be raced against with a THP
split.

This check became unneeded after 0a31bc97c80c ("mm: memcontrol: rewrite
uncharge API").

[mhocko@suse.com: changelog enhancements]
Link: http://lkml.kernel.org/r/1465369248-13865-1-git-send-email-roy.qing.li@gmail.com
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 1a1a3093a5c9..36d6e324fadc 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5580,7 +5580,6 @@ static void uncharge_list(struct list_head *page_list)
 
 			if (PageTransHuge(page)) {
 				nr_pages <<= compound_order(page);
-				VM_BUG_ON_PAGE(!PageTransHuge(page), page);
 				nr_huge += nr_pages;
 			}
 			if (PageAnon(page))