From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60360) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cEZ4o-0007VN-W0 for qemu-devel@nongnu.org; Wed, 07 Dec 2016 05:03:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cEZ4o-0001Zo-1t for qemu-devel@nongnu.org; Wed, 07 Dec 2016 05:03:50 -0500 Date: Wed, 7 Dec 2016 18:03:39 +0800 From: Fam Zheng Message-ID: <20161207100339.GB2286@lemon> References: <87oa0q1t21.fsf@dusky.pond.sub.org> <20161207025457.GB30227@lemon> <20161207094832.GA4773@noname.str.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161207094832.GA4773@noname.str.redhat.com> Subject: Re: [Qemu-devel] [Qemu-block] Meeting notes on -blockdev, dynamic backend reconfiguration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: Markus Armbruster , qemu-devel@nongnu.org, qemu-block@nongnu.org On Wed, 12/07 10:48, Kevin Wolf wrote: > > If so I think there is no race to worry about, mirror-filter should go > > away only after a QMP command. > > Currently, a mirror job goes away whenever it is done. This is not > directly tied to a QMP command. Ah right, block-job-complete is only "start to complete" and the job goes away at some later point. I thought this is "the" QMP command but it is not. > > Of course, in the new job API we want an explicit job-delete, so in > that case it wouldn't happen, but we need to keep the old case for > compatibility. Another possibility is to add a placeholder node in the right location first then fill in the actual throttling node once created. QMP owns the placeholder node so it won't suddenly vanish when mirror job goes away. Fam