[Mesa-dev] [PATCH 1/5] glx/dri3: Fix glXWaitForSbcOML() to handle targetSBC==0 correctly.

[Mario Kleiner]

On 12/04/2014 11:48 AM, Axel Davy wrote:
> Le 04/12/2014 11:44, Axel Davy a écrit :
>> On 02/12/2014 20:53, Mario Kleiner wrote :
>>> targetSBC == 0 is a special case, which asks the function
>>> to block until all pending OpenGL bufferswap requests have
>>> completed.
>>>
>>> Currently the function just falls through for targetSBC == 0,
>>> returning bogus results.
>>>
>>> This breaks applications originally written and tested against
>>> DRI2 which also rely on this not regressing under DRI3/Present,
>>> e.g., Neuro-Science software like Psychtoolbox-3.
>>>
>>> This patch fixes the problem.
>>>
>>> Cc: "10.3 10.4" <mesa-stable at lists.freedesktop.org>
>>> Signed-off-by: Mario Kleiner <mario.kleiner.de at gmail.com>
>>> ---
>>>   src/glx/dri3_glx.c | 3 ++-
>>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/src/glx/dri3_glx.c b/src/glx/dri3_glx.c
>>> index a9ff73b..b4ac278 100644
>>> --- a/src/glx/dri3_glx.c
>>> +++ b/src/glx/dri3_glx.c
>>> @@ -529,7 +529,8 @@ dri3_wait_for_sbc(__GLXDRIdrawable *pdraw, 
>>> int64_t target_sbc, int64_t *ust,
>>>   {
>>>      struct dri3_drawable *priv = (struct dri3_drawable *) pdraw;
>>>   -   while (priv->recv_sbc < target_sbc) {
>>> +   while ((target_sbc != 0 && priv->recv_sbc < target_sbc) ||
>>> +          (target_sbc == 0 && priv->recv_sbc < priv->send_sbc)) {
>>>         if (!dri3_wait_for_event(pdraw))
>>>            return 0;
>>>      }
>> Looks good to me.
>>
>> Reviewed-by: Axel Davy <axel.davy at ens.fr>
>> _______________________________________________
>>
> Just an additional thought:
>
> it would probably better to do instead:
>
> if (!target_sbc)
>     target_sbc = priv->send_sbc;

Yep. Will change it. Will also make the other suggested changes for the 
other patches and then send out a new series.

thanks,
-mario