Commit af4a6621 authored Mar 23, 2011 by Johannes Weiner Committed by Linus Torvalds Mar 23, 2011

memcg: remove NULL check from lookup_page_cgroup() result



The page_cgroup array is set up before even fork is initialized.  I
seriously doubt that this code executes before the array is alloc'd.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent c14f35c7

mm/memcontrol.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -2369,10 +2369,7 @@ static int mem_cgroup_charge_common(struct page page, struct mm_struct mm,
		}

		pc = lookup_page_cgroup(page);
		/* can happen at boot */
		if (unlikely(!pc))
		return 0;
		prefetchw(pc);
		BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */

		ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, oom, page_size);
		if (ret \|\| !mem)