Commit 54992762 authored Jan 07, 2009 by KOSAKI Motohiro Committed by Linus Torvalds Jan 08, 2009

memcg: add null check to page_cgroup_zoneinfo()



If CONFIG_CGROUP_MEM_RES_CTLR_SWAP=y, page_cgroup::mem_cgroup can be NULL.
Therefore null checking is better.

A later patch uses this function.

Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent eeee9a8c

mm/memcontrol.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -231,6 +231,9 @@ page_cgroup_zoneinfo(struct page_cgroup *pc)
		int nid = page_cgroup_nid(pc);
		int zid = page_cgroup_zid(pc);

		if (!mem)
		return NULL;

		return mem_cgroup_zoneinfo(mem, nid, zid);
		}