From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 27 Feb 2008 08:37:14 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [RFC][PATCH] radix-tree based page_cgroup. [7/7] per cpu fast lookup Message-Id: <20080227083714.fbe34483.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <44c63dc40802260526x3283baf2tb4ab71b384a4ab58@mail.gmail.com> References: <20080225120758.27648297.kamezawa.hiroyu@jp.fujitsu.com> <20080225121849.191ac900.kamezawa.hiroyu@jp.fujitsu.com> <44c63dc40802260526x3283baf2tb4ab71b384a4ab58@mail.gmail.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: minchan Kim Cc: "balbir@linux.vnet.ibm.com" , "hugh@veritas.com" , "yamamoto@valinux.co.jp" , taka@valinux.co.jp, Andi Kleen , "nickpiggin@yahoo.com.au" , "linux-mm@kvack.org" List-ID: On Tue, 26 Feb 2008 22:26:40 +0900 "minchan Kim" wrote: > > -struct page_cgroup *get_page_cgroup(struct page *page, gfp_t gfpmask) > > +struct page_cgroup *__get_page_cgroup(struct page *page, gfp_t gfpmask) > > { > > struct page_cgroup_root *root; > > struct page_cgroup *pc, *base_addr; > > @@ -96,8 +110,14 @@ retry: > > pc = radix_tree_lookup(&root->root_node, idx); > > rcu_read_unlock(); > > > > + if (pc) { > > + if (!in_interrupt()) > > + save_result(pc, idx); > > + } > > + > > I didn't look through mem_control's patches yet. > Please understand me if my question might be foolish. > > why do you prevent when it happen in interrupt context ? > Do you have any reason ? > looking up isn't done under irq disable but under preempt disable. Thanks, -Kame -- 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