From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50951) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XuPCN-0002tJ-Rz for qemu-devel@nongnu.org; Fri, 28 Nov 2014 12:19:22 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XuPCH-00027I-N6 for qemu-devel@nongnu.org; Fri, 28 Nov 2014 12:19:15 -0500 Received: from mx1.redhat.com ([209.132.183.28]:33302) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XuPCH-000275-Af for qemu-devel@nongnu.org; Fri, 28 Nov 2014 12:19:09 -0500 Date: Fri, 28 Nov 2014 17:40:23 +0100 From: Kevin Wolf Message-ID: <20141128164023.GH4035@noname.redhat.com> References: <1417183941-26329-1-git-send-email-pbonzini@redhat.com> <1417183941-26329-6-git-send-email-pbonzini@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1417183941-26329-6-git-send-email-pbonzini@redhat.com> Subject: Re: [Qemu-devel] [PATCH 5/7] coroutine: rewrite pool to avoid mutex List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: ming.lei@canonical.com, pl@kamp.de, qemu-devel@nongnu.org, stefanha@redhat.com Am 28.11.2014 um 15:12 hat Paolo Bonzini geschrieben: > I still believe we will end with some kind of coroutine bypass scheme > (even coroutines _do_ allocate an AIOCB, so calling bdrv_aio_readv > directly can help), but hey it cannot hurt to optimize hot code. Not sure if speculations about the future belong into commit messages, but while it may turn out that a bypass is required in the end (I hope it doesn't), the part about AIOCBs is wrong if you really consistently use coroutines all the way down from the device to the block driver. I think Peter picked up all of my patches to actually handle requests this way (i.e. virtio-blk already creates the coroutine). Kevin