Fix race between page flip job submission and completion. We invoke page_flip callback to submit page flip job to GPU first and then set pflip_status. If GPU fires page flip done irq in between, its handler won't see the correct pflip_status thus will refuse to notify the job completion. The job will eventually times out.
Reverse the order of calling page_flip and setting pflip_status to fix the race.
Signed-off-by: Yu Zhao yuzhao@google.com --- drivers/gpu/drm/amd/amdgpu/amdgpu_display.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c index 686a26de50f9..e309d26170db 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c @@ -105,11 +105,11 @@ static void amdgpu_display_flip_work_func(struct work_struct *__work) /* We borrow the event spin lock for protecting flip_status */ spin_lock_irqsave(&crtc->dev->event_lock, flags);
+ /* Set the flip status */ + amdgpu_crtc->pflip_status = AMDGPU_FLIP_SUBMITTED; /* Do the flip (mmio) */ adev->mode_info.funcs->page_flip(adev, work->crtc_id, work->base, work->async);
- /* Set the flip status */ - amdgpu_crtc->pflip_status = AMDGPU_FLIP_SUBMITTED; spin_unlock_irqrestore(&crtc->dev->event_lock, flags);