From: Paolo Bonzini <pbonzini@redhat.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Christoph Hellwig <chellwig@redhat.com>,
Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
Rusty Russell <rusty@rustcorp.com.au>,
qemu-devel <qemu-devel@nongnu.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Hannes Reinecke <hare@suse.de>,
Linux Virtualization <virtualization@lists.linux-foundation.org>
Subject: Re: [Qemu-devel] virtio scsi host draft specification, v3
Date: Wed, 29 Jun 2011 10:23:26 +0200 [thread overview]
Message-ID: <4E0AE0FE.2090905@redhat.com> (raw)
In-Reply-To: <20110612075140.GB11941@redhat.com>
On 06/12/2011 09:51 AM, Michael S. Tsirkin wrote:
>> >
>> > If a device uses more than one queue it is the responsibility of the
>> > device to ensure strict request ordering.
> Maybe I misunderstand - how can this be the responsibility of
> the device if the device does not get the information about
> the original ordering of the requests?
>
> For example, if the driver is crazy enough to put
> all write requests on one queue and all barriers
> on another one, how is the device supposed to ensure
> ordering?
I agree here, in fact I misread Hannes's comment as "if a driver uses
more than one queue it is responsibility of the driver to ensure strict
request ordering". If you send requests to different queues, you know
that those requests are independent. I don't think anything else is
feasible in the virtio framework.
Paolo
next prev parent reply other threads:[~2011-06-29 8:23 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-07 13:43 [Qemu-devel] virtio scsi host draft specification, v3 Paolo Bonzini
2011-06-08 23:28 ` Rusty Russell
2011-06-09 6:59 ` Paolo Bonzini
2011-06-10 11:33 ` Rusty Russell
2011-06-10 12:14 ` Stefan Hajnoczi
2011-06-10 12:22 ` Paolo Bonzini
2011-06-10 12:55 ` Hannes Reinecke
2011-06-10 14:35 ` Paolo Bonzini
2011-06-14 8:39 ` Hannes Reinecke
2011-06-14 15:53 ` Stefan Hajnoczi
2011-06-29 8:33 ` Paolo Bonzini
2011-06-29 9:39 ` Stefan Hajnoczi
2011-06-29 10:07 ` Christoph Hellwig
2011-06-29 10:23 ` Hannes Reinecke
2011-06-29 10:27 ` Christoph Hellwig
2011-07-01 6:41 ` Paolo Bonzini
2011-07-01 7:14 ` Hannes Reinecke
2011-07-01 8:35 ` Paolo Bonzini
2011-07-04 13:38 ` Hai Dong,Li
2011-07-04 14:22 ` Stefan Hajnoczi
2011-06-12 7:51 ` Michael S. Tsirkin
2011-06-14 15:30 ` Hannes Reinecke
2011-06-29 10:00 ` Christoph Hellwig
2011-06-29 8:23 ` Paolo Bonzini [this message]
2011-06-29 8:46 ` Michael S. Tsirkin
2011-06-29 10:03 ` Christoph Hellwig
2011-06-29 10:06 ` Paolo Bonzini
2011-06-29 10:31 ` Michael S. Tsirkin
2011-06-29 10:35 ` Paolo Bonzini
2011-06-29 10:01 ` Christoph Hellwig
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4E0AE0FE.2090905@redhat.com \
--to=pbonzini@redhat.com \
--cc=chellwig@redhat.com \
--cc=hare@suse.de \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mst@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=rusty@rustcorp.com.au \
--cc=stefanha@linux.vnet.ibm.com \
--cc=virtualization@lists.linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).