[Mesa-dev] [PATCH] vulkan/wsi: Avoid waiting indefinitely for present completion in x11_manage_fifo_queues().

[Henri Verbeet]

On 24 October 2017 at 20:31, Emil Velikov <emil.l.velikov at gmail.com> wrote:
> On 17 October 2017 at 15:18, Henri Verbeet <hverbeet at gmail.com> wrote:
>> Note that the usage of xcb_poll_for_special_event() requires a version
>> of libxcb that includes commit fad81b63422105f9345215ab2716c4b804ec7986
>> to work properly.
>>
> What should we expect if we're using xcb w/o said commit? It's worth
> mentioning in the commit message.

For reference, https://cgit.freedesktop.org/xcb/libxcb/commit/?id=fad81b63422105f9345215ab2716c4b804ec7986

What happens without that commit is that xcb_poll_for_special_event()
will fail to read the event, effectively preventing any subsequent
presents. That's obviously bad. As mentioned in the libxcb commit, a
similar issue exists for x11_acquire_next_image_poll_x11() with a
timeout, although I suppose that scenario is less common.

> it seems like there's no release with the commit, should we bribe Uli
> to roll one ;-)
>
Probably.