From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 20 Mar 2008 14:09:43 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH 5/7] radix-tree page cgroup Message-Id: <20080320140943.6d879380.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20080320134513.3e4d45f1.kamezawa.hiroyu@jp.fujitsu.com> References: <20080314185954.5cd51ff6.kamezawa.hiroyu@jp.fujitsu.com> <20080314191733.eff648f8.kamezawa.hiroyu@jp.fujitsu.com> <1205961066.6437.10.camel@lappy> <20080320134513.3e4d45f1.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: Peter Zijlstra , "linux-mm@kvack.org" , "balbir@linux.vnet.ibm.com" , xemul@openvz.org, "hugh@veritas.com" List-ID: On Thu, 20 Mar 2008 13:45:13 +0900 KAMEZAWA Hiroyuki wrote: > > > > + base_pfn = idx << PCGRP_SHIFT; > > > +retry: > > > + error = 0; > > > + rcu_read_lock(); > > > + head = radix_tree_lookup(&root->root_node, idx); > > > + rcu_read_unlock(); > > > > This looks iffy, who protects head here? > > > > In this patch, a routine for freeing "head" is not included. > Then....Hmm.....rcu_read_xxx is not required...I'll remove it. > I'll check the whole logic around here again. > Sorry, I was confused...for radix-tree, ruc_xxx is necessary. Regards, -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