From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55125) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yxt6B-0005OU-6D for qemu-devel@nongnu.org; Thu, 28 May 2015 04:23:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yxt69-00045y-PX for qemu-devel@nongnu.org; Thu, 28 May 2015 04:23:31 -0400 Message-ID: <5566D076.8010807@redhat.com> Date: Thu, 28 May 2015 10:23:18 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1432190583-10518-1-git-send-email-famz@redhat.com> <1432190583-10518-2-git-send-email-famz@redhat.com> <20150526142210.GI24077@noname.str.redhat.com> <55648220.1030206@redhat.com> <20150527090745.GA4669@noname.str.redhat.com> <55659372.9060804@redhat.com> <20150527101016.GB4669@noname.str.redhat.com> <55659FCC.2030704@redhat.com> <20150528024950.GC22609@dhcp-14-238.nay.redhat.com> In-Reply-To: <20150528024950.GC22609@dhcp-14-238.nay.redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v6 01/13] block: Add op blocker type "device IO" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng Cc: Kevin Wolf , qemu-block@nongnu.org, qemu-devel@nongnu.org, jcody@redhat.com, armbru@redhat.com, Max Reitz , Stefan Hajnoczi , amit.shah@redhat.com On 28/05/2015 04:49, Fam Zheng wrote: > > On a second thought, although in this series, we only need to modify > virtio-{scsi,blk}, Wen pointed out that mirror job also wants this during > completion (because bdrv_swap is in a BH after the job coroutine returns). Mirror needs to pause/resume the source. It doesn't need to handle pause/resume of the target, does it? > So, in order for the solution to be general, and complete, this nofitier list > approach relies on the listening devices to do the right thing, which requires > modifying all of them, and is harder to maintain. Isn't it only devices that use aio_set_event_notifier for their ioeventfd? Paolo