[PATCH 5/5] drm/radeon: rework page flip handling v3

[Christian König]

Am 03.06.2014 15:31, schrieb Alex Deucher:
> On Wed, May 28, 2014 at 2:56 AM, Michel Dänzer <michel at daenzer.net> wrote:
>> On 27.05.2014 23:49, Christian König wrote:
>>> From: Christian König <christian.koenig at amd.com>
>>>
>>> Instead of trying to flip inside the vblank period when
>>> the buffer is idle, offload blocking for idle to a kernel
>>> thread and program the flip directly into the hardware.
>>>
>>> v2: add error handling, fix EBUSY handling
>>> v3: add proper exclusive_lock handling
>> [...]
>>
>>> +     /* update crtc fb */
>>> +     crtc->primary->fb = fb;
>>> +
>>> +     /* We borrow the event spin lock for protecting flip_work */
>>> +     spin_lock_irqsave(&crtc->dev->event_lock, flags);
>>> +
>>> +     if (radeon_crtc->flip_work) {
>>> +             DRM_DEBUG_DRIVER("flip queue: crtc already busy\n");
>>> +             spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
>>> +             drm_gem_object_unreference_unlocked(&work->old_rbo->gem_base);
>>> +             radeon_fence_unref(&work->fence);
>>> +             kfree(work);
>>> +             return -EBUSY;
>>> +     }
>> If we return -EBUSY, we shouldn't change crtc->primary->fb, should we? I
>> wonder if crtc->primary->fb shouldn't be changed in
>> radeon_flip_work_func(), when we're sure we can actually flip.
> How about this?

Looks good to me. Reviewed-by: Christian König <christian.koenig at amd.com>

>
> Alex