From: Kevin Wolf <kwolf@redhat.com>
To: Christoph Hellwig <hch@lst.de>
Cc: devin122@gmail.com, Stefan Hajnoczi <stefanha@gmail.com>,
Jagane Sundar <jagane@sundar.org>, Dor Laor <dlaor@redhat.com>,
qemu-devel <qemu-devel@nongnu.org>,
Markus Armbruster <armbru@redhat.com>,
Feiran Zheng <famcool@gmail.com>,
Frediano Ziglio <freddy77@gmail.com>,
Jes Sorensen <Jes.Sorensen@redhat.com>,
Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [Qemu-devel] Block layer roadmap
Date: Thu, 28 Jul 2011 14:35:26 +0200 [thread overview]
Message-ID: <4E31578E.2080704@redhat.com> (raw)
In-Reply-To: <20110728120931.GB17045@lst.de>
Am 28.07.2011 14:09, schrieb Christoph Hellwig:
> On Wed, Jul 27, 2011 at 01:37:31PM +0100, Stefan Hajnoczi wrote:
>> Coroutines in the block layer [Kevin]
>> * Programming model to simplify block drivers without blocking QEMU threads
>
> Can anyone explain what the whole point of this is? It really just is
> a bit of syntactic sugar for the current async state machines. What does
> it buy us over going for real threading?
The only current block driver that really does everything in an async
state machine is qed. It's definitely not nice code, and having to
convert all of the other block drivers to this would be a lot of work.
So if it only means that we're making things async that would block the
VCPU until now, isn't that a great improvement already?
The advantage compared to threading is that it allows an easy and
incremental transition.
Kevin
next prev parent reply other threads:[~2011-07-28 12:32 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-27 12:37 [Qemu-devel] Block layer roadmap Stefan Hajnoczi
2011-07-27 12:50 ` Anthony Liguori
2011-07-28 10:05 ` Kevin Wolf
2011-07-28 12:08 ` Christoph Hellwig
2011-07-28 12:29 ` Kevin Wolf
2011-07-28 10:52 ` Stefan Hajnoczi
2011-07-28 12:09 ` Christoph Hellwig
2011-07-28 12:15 ` Frediano Ziglio
2011-07-28 12:16 ` Christoph Hellwig
2011-07-28 12:35 ` Kevin Wolf [this message]
2011-07-28 12:54 ` Stefan Hajnoczi
2011-07-28 13:10 ` Kevin Wolf
2011-07-28 13:11 ` Stefan Hajnoczi
2011-07-28 12:52 ` Anthony Liguori
2011-07-29 12:35 ` Stefan Hajnoczi
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=4E31578E.2080704@redhat.com \
--to=kwolf@redhat.com \
--cc=Jes.Sorensen@redhat.com \
--cc=armbru@redhat.com \
--cc=devin122@gmail.com \
--cc=dlaor@redhat.com \
--cc=famcool@gmail.com \
--cc=freddy77@gmail.com \
--cc=hch@lst.de \
--cc=jagane@sundar.org \
--cc=pbonzini@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@gmail.com \
/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).