From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 11 Sep 2008 20:20:02 +0900 From: KAMEZAWA Hiroyuki Subject: [RFC] [PATCH 7/9] memcg: charge likely success Message-Id: <20080911202002.d644bc59.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20080911200855.94d33d3b.kamezawa.hiroyu@jp.fujitsu.com> References: <20080911200855.94d33d3b.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: KAMEZAWA Hiroyuki Cc: balbir@linux.vnet.ibm.com, "xemul@openvz.org" , "hugh@veritas.com" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, menage@google.com List-ID: In fast path, res_counter_charge() will success. This annotation 'unlikely' works very well to make footprint shorter. (And you can see the benefit of this by some benchmarks.) Signed-off-by: KAMEZAWA Hiroyuki Index: mmtom-2.6.27-rc5+/mm/memcontrol.c =================================================================== --- mmtom-2.6.27-rc5+.orig/mm/memcontrol.c +++ mmtom-2.6.27-rc5+/mm/memcontrol.c @@ -683,7 +683,7 @@ static int mem_cgroup_charge_common(stru css_get(&memcg->css); } - while (res_counter_charge(&mem->res, PAGE_SIZE)) { + while (unlikely(res_counter_charge(&mem->res, PAGE_SIZE))) { if (!(gfp_mask & __GFP_WAIT)) goto out; -- 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/ . Don't email: email@kvack.org