Re: [Qemu-devel] [Qemu-block] [PATCH v2 11/11] block: Only poll block layer fds in bdrv_aio_poll

["Daniel P. Berrange" <berrange@redhat.com>]

On Fri, Sep 11, 2015 at 11:36:10AM +0200, Alberto Garcia wrote:
> On Fri 11 Sep 2015 11:14:33 AM CEST, Fam Zheng <famz@redhat.com> wrote:
> 
> >> > Another advantage for bdrv_aio_poll() is, in main loop we will not
> >> > need a separate AioContext in changes like:
> >> > 
> >> > http://patchwork.ozlabs.org/patch/514968/
> >> > 
> >> > Because nested aio_poll will automatically be limited to only
> >> > process block layer events. My idea is to eventually let main loop
> >> > use aio_poll
> >> 
> >> That would be a step back.  Using GSource is useful because it lets
> >> you integrate libraries such as GTK+.
> >
> > Can we move GTK to a separate GSource thread?
> 
> I think that GTK should always run in the main thread, or at least the
> one running the default main loop / GMainContext.

In theory GTK can run from a separate thread, but my experiance with
GTK and threads is that you end up in a world of hurt if you try to
anything except use the main thread, so I'd really recommend against
it. Even if you do extensive testing locally, things still break across
different GTK versions people have, so its just not worth the pain.

Regards,
Daniel
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