From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id C2B568D0039 for ; Thu, 3 Feb 2011 09:12:42 -0500 (EST) Date: Thu, 3 Feb 2011 15:12:30 +0100 From: Johannes Weiner Subject: [patch rfc] memcg: remove NULL check from lookup_page_cgroup() result Message-ID: <20110203141230.GG2286@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: KAMEZAWA Hiroyuki , Daisuke Nishimura , Balbir Singh , linux-mm@kvack.org, linux-kernel@vger.kernel.org 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 --- mm/memcontrol.c | 5 +---- 1 files changed, 1 insertions(+), 4 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index a145c9e..6abaa10 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2343,10 +2343,7 @@ 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) -- 1.7.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org