From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <44D7E7DF.1080106@yahoo.com.au> Date: Tue, 08 Aug 2006 11:24:47 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: 2.6.18-rc3-mm2: rcu radix tree patches break page migration References: In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: npiggin@suse.de, linux-mm@kvack.org, Lee Schermerhorn List-ID: Christoph Lameter wrote: > If I take the following patches out then page migration works reliably > again. Otherwise page migration may result in weird values in the > page struct. Reproduce by trying to migrate the executable pages > of a running process. This usually creates enough races to break things. > AFAIK the current radix tree rcu patches do not change the behavior > of the tree_lock at all. > > radix-tree-rcu-lockless-readside.patch > redo-radix-tree-fixes.patch > adix-tree-rcu-lockless-readside-update.patch > radix-tree-rcu-lockless-readside-semicolon.patch > adix-tree-rcu-lockless-readside-update-tidy.patch > adix-tree-rcu-lockless-readside-fix-2.patch > > Output in one failure scenario (after migrating the memory of cron back > and forth between nodes): Yeah Lee noticed this as well... Question: can you replace the lookup_slot with a regular lookup, then replace the pointer switch with a radix_tree_delete + radix_tree_insert and see if that works? Thanks, Nick -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com -- 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