From: Christoph Hellwig <hch@lst.de>
To: Avi Kivity <avi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] barriers: block layer preparations
Date: Tue, 5 May 2009 22:57:16 +0200 [thread overview]
Message-ID: <20090505205716.GA24320@lst.de> (raw)
In-Reply-To: <4A00446B.7070404@redhat.com>
On Tue, May 05, 2009 at 04:51:39PM +0300, Avi Kivity wrote:
> >+ qcow_aio_write_cb, acb, 2);
> >
>
> 2?
Typo.
> An alternative approach is to add a new op, bdrv_aio_barrier(),
> submitted immediately after the write. It's probably more complicated
> overall.
Yeah, it sounds more complicated to implement to me.
> A barrier for read can be meaningful if the guest wishes to read a
> known-to-be-stable write. I don't think any guest can make use of this
> though.
I don't know of any storage standard having anything like this or any
OS taking advantage of it. I'd be happy to review anything like that,
though.
next prev parent reply other threads:[~2009-05-05 20:57 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-05 12:08 [Qemu-devel] [PATCH 0/3] write barrier support Christoph Hellwig
2009-05-05 12:08 ` [Qemu-devel] barriers: block layer preparations Christoph Hellwig
2009-05-05 13:51 ` Avi Kivity
2009-05-05 15:38 ` Jamie Lokier
2009-05-05 15:49 ` Avi Kivity
2009-05-05 16:00 ` Jamie Lokier
2009-05-05 20:57 ` Christoph Hellwig [this message]
2009-05-05 22:49 ` Jamie Lokier
2009-05-05 12:08 ` [Qemu-devel] [PATCH 2/3] barriers: block-raw-posix barrier support Christoph Hellwig
2009-05-05 12:33 ` Jamie Lokier
2009-05-05 13:29 ` Christoph Hellwig
2009-05-05 16:00 ` Jamie Lokier
2009-05-05 12:09 ` [Qemu-devel] [PATCH 3/3] barriers: virtio Christoph Hellwig
2009-05-05 13:53 ` [Qemu-devel] [PATCH 0/3] write barrier support Avi Kivity
2009-05-05 21:00 ` Christoph Hellwig
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