From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:50868) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TRQuZ-0007DH-Gw for qemu-devel@nongnu.org; Thu, 25 Oct 2012 13:08:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TRQuX-0007aW-UH for qemu-devel@nongnu.org; Thu, 25 Oct 2012 13:08:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:11146) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TRQuX-0007aM-M4 for qemu-devel@nongnu.org; Thu, 25 Oct 2012 13:08:01 -0400 Message-ID: <508971E2.9050309@redhat.com> Date: Thu, 25 Oct 2012 19:07:46 +0200 From: Avi Kivity MIME-Version: 1.0 References: <1350897839-29593-1-git-send-email-pingfank@linux.vnet.ibm.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [patch v4 00/16] push mmio dispatch out of big lock List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: Liu Ping Fan , Stefan Hajnoczi , Marcelo Tosatti , qemu-devel@nongnu.org, Anthony Liguori , Jan Kiszka , Paolo Bonzini On 10/25/2012 04:04 PM, Peter Maydell wrote: > On 22 October 2012 10:23, Liu Ping Fan wrote: >> v1: >> https://lists.gnu.org/archive/html/qemu-devel/2012-07/msg03312.html >> >> v2: >> http://lists.gnu.org/archive/html/qemu-devel/2012-08/msg01275.html >> >> v3: >> http://lists.nongnu.org/archive/html/qemu-devel/2012-09/msg01474.html > > Is there a clear up to date description somewhere of the design and > locking strategy here somewhere? I'd rather not have to try to > reconstitute it by reading the whole patchset... It was described somewhere in a document by Marcelo and myself. Basically the goal is to arrive at address_space_write(): rcu_read_lock() mr = lookup() mr->ref() rcu_read_unlock() mr->dispatch() mr->unref() This is the same strategy used in many places in the kernel. -- error compiling committee.c: too many arguments to function