From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: RCU red-black tree (was: Re: [PATCH 4/6] kvm tools: Add rwlock wrapper) Date: Tue, 31 May 2011 17:25:39 +0200 Message-ID: <20110531152539.GA22353@elte.hu> References: <20110529170104.GA17189@Krystal> <1306691292.14564.12.camel@lappy> <20110530025414.GA25865@Krystal> <1306735631.14564.34.camel@lappy> <20110530173844.GA13361@Krystal> <1306777969.15912.3.camel@lappy> <20110530185757.GA13903@Krystal> <1306847114.25406.9.camel@lappy> <20110531130923.GA13888@elte.hu> <1306848006.25406.11.camel@lappy> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Mathieu Desnoyers , Pekka Enberg , Avi Kivity , john@jfloren.net, kvm@vger.kernel.org, asias.hejun@gmail.com, gorcunov@gmail.com, prasadjoshi124@gmail.com, "Paul E. McKenney" , Phil Howard , rp@svcs.cs.pdx.edu To: Sasha Levin Return-path: Received: from mx2.mail.elte.hu ([157.181.151.9]:47355 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755762Ab1EaPZy (ORCPT ); Tue, 31 May 2011 11:25:54 -0400 Content-Disposition: inline In-Reply-To: <1306848006.25406.11.camel@lappy> Sender: kvm-owner@vger.kernel.org List-ID: * Sasha Levin wrote: > On Tue, 2011-05-31 at 15:09 +0200, Ingo Molnar wrote: > > * Sasha Levin wrote: > > > > > I've started working on converting our MMIO code to use RCU rbtree. > > > > Well, why would we want to switch the MMIO code away from the brlock > > right now? mmio tree reconfigurations are very, very rare. > > > > Won't something like the qcow cache be more suitable for that? That > > has both frequent read and write activities. > > We don't have a qcow cache at the moment :) Wasnt one in the works by Prasad? > It was either the MMIO or the ioport tree. We don't have to pull > them into our master tree either - it's mostly a proof of concept > I'm doing on a separate tree. Sure. Thanks, Ingo