From mboxrd@z Thu Jan 1 00:00:00 1970 From: kamezawa.hiroyu@jp.fujitsu.com Message-ID: <20398498.1206029708926.kamezawa.hiroyu@jp.fujitsu.com> Date: Fri, 21 Mar 2008 01:15:08 +0900 (JST) Subject: Re: Re: Re: Re: [PATCH 7/7] memcg: freeing page_cgroup at suitable chance In-Reply-To: <1206029390.8514.403.camel@twins> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-2022-jp" Content-Transfer-Encoding: 7bit References: <1206029390.8514.403.camel@twins> <22163671.1206024572593.kamezawa.hiroyu@jp.fujitsu.com> <1205999706.8514.394.camel@twins> <20080314185954.5cd51ff6.kamezawa.hiroyu@jp.fujitsu.com> <20080314192253.edb38762.kamezawa.hiroyu@jp.fujitsu.com> <1205962399.6437.30.camel@lappy> <20080320140703.935073df.kamezawa.hiroyu@jp.fujitsu.com> <2248236.1206029072224.kamezawa.hiroyu@jp.fujitsu.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Peter Zijlstra Cc: kamezawa.hiroyu@jp.fujitsu.com, linux-mm@kvack.org, balbir@linux.vnet.ibm.com, xemul@openvz.org, hugh@veritas.com List-ID: >> When we free entries of [pfn, pfn + 1 << order), [pfn, pfn + 1 << order) >> is in freelist and we have zone->lock. Lookup against [pfn, pfn + 1 << orde r) >> cannot happen against freed pages. >> Then, looking up and freeing an idx cannot happen at the same time. >> >> radix_tree_lookup() can look up wrong entry in this case ? > >You're right, my bad. > your text was very much help for understanding my own codes again... I'll add enough texts. It seems this use of radix-tree is tricky. 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