From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:48209) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S4Yw2-0008WL-RD for qemu-devel@nongnu.org; Mon, 05 Mar 2012 09:30:52 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1S4Yw1-0006V0-04 for qemu-devel@nongnu.org; Mon, 05 Mar 2012 09:30:46 -0500 Received: from thoth.sbs.de ([192.35.17.2]:23906) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S4Yw0-0006UY-LZ for qemu-devel@nongnu.org; Mon, 05 Mar 2012 09:30:44 -0500 Message-ID: <4F54CE10.4040407@siemens.com> Date: Mon, 05 Mar 2012 15:30:40 +0100 From: Jan Kiszka MIME-Version: 1.0 References: <1330936455-23802-1-git-send-email-pbonzini@redhat.com> <4F548263.1070905@siemens.com> <4F54CC8A.5010509@redhat.com> In-Reply-To: <4F54CC8A.5010509@redhat.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH] fix select(2) race between main_loop_wait and qemu_aio_wait List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Avi Kivity Cc: "anthony@codemonkey.ws" , Paolo Bonzini , "qemu-devel@nongnu.org" , "kvm@vger.kernel.org" , "laurent@vivier.eu" On 2012-03-05 15:24, Avi Kivity wrote: >> Long-term, I'd like to cut out certain file descriptors from the main >> loop and process them completely in separate threads (for separate >> locking, prioritization etc.). Dunno how NBD works, but maybe it should >> be reworked like this already. > > Ideally qemu_set_fd_handler2() should be made thread local, and each > device thread would run a copy of the main loop, just working on > different data. qemu_set_fd_handler2 may not only be called over an iothread. Rather, we need an object and associated lock that is related to the io-path (i.e. frontend device + backend driver). That object has to be passed to services like qemu_set_fd_handler2. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux