Re: [Qemu-devel] [PATCH 3/3] iothread: delay the context release to finalize

[Peter Xu]

On Mon, Sep 25, 2017 at 01:30:02PM +0800, Fam Zheng wrote:
> On Mon, 09/25 13:23, Peter Xu wrote:
> > On Fri, Sep 22, 2017 at 09:09:22PM +0800, Fam Zheng wrote:
> > > On Fri, 09/22 16:56, Peter Xu wrote:
> > > > When gcontext is used with iothread, the context will be destroyed
> > > > during iothread_stop().  That's not good since sometimes we would like
> > > > to keep the resources until iothread is destroyed, but we may want to
> > > > stop the thread before that point.
> > > 
> > > Would be nice if you can also mention the glib bug that "required" this 
> > > in the
> > > commit message.
> > 
> > I can add it, but I am not sure it's very closely related (and I'm
> > afraid that may confuse more people).  Say, even without that bug, I
> > would still think it not a good idea to free the context in the loop,
> > especially considering that we have the finalize function there.  Thanks,
> 
> It's interesting to know if or not your future change will break without this
> patch, this is especially useful for backport.

I haven't tried to run with iothread and without this patch, but I
think it should fail, so this patch should be needed.

The point is that we should not destroy the context before explicitly
calling remove_fd_in_watch() if the context is running chardevs.
Without this patch, this rule does not satisfy.  And IIUC this rule
comes from the glib bug.

Anyway, I'll mention it in commit message to clarify.

-- 
Peter Xu