From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH v7 16/46] virtio_blk: v1.0 support Date: Mon, 1 Dec 2014 14:51:26 +0200 Message-ID: <20141201125126.GB18106@redhat.com> References: <1417359787-10138-1-git-send-email-mst@redhat.com> <1417359787-10138-17-git-send-email-mst@redhat.com> <20141201091641.3085e682@thinkpad-w530> <20141201092658.GC15607@redhat.com> <20141201123315.1b95d06f.cornelia.huck@de.ibm.com> <20141201114645.GA17505@redhat.com> <20141201130258.6f01c1e3.cornelia.huck@de.ibm.com> <20141201123455.GA17958@redhat.com> <20141201134036.726e7386.cornelia.huck@de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20141201134036.726e7386.cornelia.huck@de.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Cornelia Huck Cc: thuth@linux.vnet.ibm.com, rusty@au1.ibm.com, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, David Hildenbrand , pbonzini@redhat.com, David Miller List-Id: linux-api@vger.kernel.org On Mon, Dec 01, 2014 at 01:40:36PM +0100, Cornelia Huck wrote: > On Mon, 1 Dec 2014 14:34:55 +0200 > "Michael S. Tsirkin" wrote: > > > On Mon, Dec 01, 2014 at 01:02:58PM +0100, Cornelia Huck wrote: > > > On Mon, 1 Dec 2014 13:46:45 +0200 > > > "Michael S. Tsirkin" wrote: > > > > > > > On Mon, Dec 01, 2014 at 12:33:15PM +0100, Cornelia Huck wrote: > > > > > On Mon, 1 Dec 2014 11:26:58 +0200 > > > > > "Michael S. Tsirkin" wrote: > > > > > > > > > > > For some places on data path, it might be worth it > > > > > > to cache the correct value e.g. as part of device > > > > > > structure. This replaces a branch with a memory load, > > > > > > so the gain would have to be measured, best done > > > > > > separately? > > > > > > > > > > I think we'll want to do some measuring once the basic structure is > > > > > in place anyway. > > > > > > > > What's meant by in place here? > > > > > > That this patchset is ready :) > > > > Also it's ready to the level where benchmarking is possible, right? I > > don't think you should wait until we finish polishing up commit > > messages. > > My point is that I haven't even found time yet to test this > thouroughly :( If my experience shows anything, it's unlikely we'll get appropriate testing without code being upstream first. That's why I pushed on with sparse tagging btw. This way we can be reasonably sure we didn't miss some path. -- MST