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Date: Thu, 28 Sep 2017 10:43:27 +0800
From: Peter Xu <peterx@redhat.com>
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Subject: Re: [Qemu-devel] A glib warning encountered with internal iothread
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Fam Zheng <famz@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, QEMU Devel Mailing List <qemu-devel@nongnu.org>

On Wed, Sep 27, 2017 at 03:14:40PM +0200, Paolo Bonzini wrote:
> On 27/09/2017 14:36, Fam Zheng wrote:
> > On Wed, 09/27 13:17, Stefan Hajnoczi wrote:
> >> On Tue, Sep 26, 2017 at 07:13:43PM +0800, Fam Zheng wrote:
> >>> On Tue, 09/26 17:11, Peter Xu wrote:
> >>>  void aio_context_unref(AioContext *ctx)
> >>>  {
> >>> +    assert(ctx->refcnt > 0);
> >>> +    if (--ctx->refcnt == 0) {
> >>> +        aio_set_event_notifier(ctx, &ctx->notifier, false, NULL, NULL);
> >>> +    }
> >>
> >> This isn't a general solution because Linux AIO also has a file
> >> descriptor that is removed in aio_ctx_finalize().
> > 
> > Right. Another option is to move everything in aio_context_finalize() into the
> > "if (--ctx->refcnt == 0) { ... }" block, before calling g_source_unref().
> 
> I think I prefer Stefan's solution.  If the GSource has been ref'ed
> independent of the AioContext object, it may be a problem to free it early.

Stefan's patch works for me.  I'll put Stefan's patch into iothread
series and repost soon.

Thanks Stefan (and all)!

-- 
Peter Xu