[Mesa-dev] [PATCH] gbm/dri: Flush after unmap

[Thomas Hellstrom]

On 03/30/2017 05:48 AM, Michel Dänzer wrote:
> On 30/03/17 12:56 AM, Thomas Hellstrom wrote:
>> On 03/29/2017 02:34 PM, Emil Velikov wrote:
>>> On 29 March 2017 at 13:02, Thomas Hellstrom <thellstrom at vmware.com> wrote:
>>>> On 03/29/2017 01:30 PM, Emil Velikov wrote:
>>>>> On 28 March 2017 at 20:39, Thomas Hellstrom <thellstrom at vmware.com> wrote:
>>>>>> Signed-off-by: Thomas Hellstrom <thellstrom at vmware.com>
>>>>>> ---
>>>>>>  src/gbm/backends/dri/gbm_dri.c | 9 ++++++++-
>>>>>>  1 file changed, 8 insertions(+), 1 deletion(-)
>>>>>>
>>>>>> diff --git a/src/gbm/backends/dri/gbm_dri.c b/src/gbm/backends/dri/gbm_dri.c
>>>>>> index ac7ede8..6c2244c 100644
>>>>>> --- a/src/gbm/backends/dri/gbm_dri.c
>>>>>> +++ b/src/gbm/backends/dri/gbm_dri.c
>>>>>> @@ -243,7 +243,7 @@ struct dri_extension_match {
>>>>>>  };
>>>>>>
>>>>>>  static struct dri_extension_match dri_core_extensions[] = {
>>>>>> -   { __DRI2_FLUSH, 1, offsetof(struct gbm_dri_device, flush) },
>>>>>> +   { __DRI2_FLUSH, 4, offsetof(struct gbm_dri_device, flush) },
>>>>> Currently the classic nouveau, radeon/r200 and i915 drivers do not
>>>>> support v4 of the extension.
>>>>> As-is this will 'break' them... if they ever worked to begin with.
>>>>>
>>>>> One solution is to bail out (return -ENOSYS or similar) in map/unmap
>>>>> API of the when the DRI module is too old.
>>>>> Just some ^^ food for thought.
>>>> Hmm. Is there even a use-case for gbm with those drivers? If so we
>>>> should perhaps make them up-to-date with the flush extension.
>>>>
>>> Of the above:
>>>
>>> - nouveau: Does not support DRI_IMAGE, thus it doesn't work even
>>> before the patch.
>>> - i915: I have some untested ancient patches. Will see if I can rebase
>>> + send out.
>>> - radeons: ??
>>>
>>> If someone reports an issue we can ask them to write/test some code, I guess ;-)
>> Indeed. It looks like gbm is mostly used together with KMS anyway...
> All of the above drivers are KMS based, FWIW.
>
>
Do you think it's worthwhile to have them functioning with GBM?

I can of course condition the flush on version 4 or above if necessary.

/Thomas