From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40727) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XH8av-0006eV-8n for qemu-devel@nongnu.org; Tue, 12 Aug 2014 05:42:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XH8ao-0002wh-Rv for qemu-devel@nongnu.org; Tue, 12 Aug 2014 05:42:17 -0400 Received: from mx1.redhat.com ([209.132.183.28]:19130) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XH8ao-0002wQ-LX for qemu-devel@nongnu.org; Tue, 12 Aug 2014 05:42:10 -0400 Date: Tue, 12 Aug 2014 10:36:32 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20140812093632.GD2384@work-vm> References: <1407767399-3030-1-git-send-email-dgilbert@redhat.com> <1407767399-3030-7-git-send-email-dgilbert@redhat.com> <047A6D07C7C75B4D95D277304F90FDF22198BEC4@SZXEML506-MBS.china.huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <047A6D07C7C75B4D95D277304F90FDF22198BEC4@SZXEML506-MBS.china.huawei.com> Subject: Re: [Qemu-devel] ????: [PATCH v2 06/43] Return path: socket_writev_buffer:?Block even on non-blocking fd's List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "chenliang (T)" Cc: "qemu-devel@nongnu.org" * chenliang (T) (chenliang88@huawei.com) wrote: > > From: "Dr. David Alan Gilbert" > > The return path uses a non-blocking fd so as not to block waiting for the (possibly broken) destination to finish returning a message, however we still want outbound data to behave in the same way and block. > > Signed-off-by: Dr. David Alan Gilbert > > Hi David > It is confusing why don't use blocking fd? I want to make sure that if the destination guest hung during sending a return path command, that the source wouldn't block the main thread (in which I'm currently processing the RP commands). Paolo made a suggestion to move the RP processing to a separate thread, which would also avoid the problem, and I'll be trying that. Dave > Best regards -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK