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Date: Wed, 28 Sep 2011 10:00:44 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] event_notifier: move to top-level directory
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Avi Kivity <avi@redhat.com>

On 09/28/2011 09:52 AM, Jan Kiszka wrote:
> >  You can probably assume that qemu_notify_event (and dually the read in
> >  the main loop) are resp. write/read memory barriers.  Or even full.
> >
> >  If we switch entirely to GSources, it would be nice to use them.  But
> >  since we aren't, and our main loop functionality is quite different from
> >  glib's (it doesn't rely on abstractions for file descriptors, for
> >  example), it is just a painful incomplete transition to use glib's idle
> >  sources to do the exact same thing that is done by bottom halves (which
> >  are already in our toolbox).
>
> BTW, I just wondered if there is anything conceptually preventing to
> skip this ping pong between AIO thread and main loop and just run the
> completion over the former context (under global lock protection of course).

Would be a good idea, but it would require some refactoring because 
tools do not have a global lock.

Paolo