On Tue, Apr 14, 2015 at 08:22:20PM +0200, Mario Kleiner wrote:
On 04/05/2015 05:40 PM, Chris Wilson wrote:
Avoid adding to the waitqueue and reprobing the current vblank if the caller is only querying the current vblank sequence and timestamp and so we would return immediately.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Daniel Vetter daniel@ffwll.ch Cc: Michel Dänzer michel@daenzer.net Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Cc: Dave Airlie airlied@redhat.com, Cc: Mario Kleiner mario.kleiner.de@gmail.com
drivers/gpu/drm/drm_irq.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 6f5dc18779e2..ba80b51b4b00 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -1617,14 +1617,16 @@ int drm_wait_vblank(struct drm_device *dev, void *data, vblwait->request.sequence = seq + 1; }
- DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
vblwait->request.sequence, crtc);- vblank->last_wait = vblwait->request.sequence;
- DRM_WAIT_ON(ret, vblank->queue, 3 * HZ,
(((drm_vblank_count(dev, crtc) -vblwait->request.sequence) <= (1 << 23)) ||!vblank->enabled ||!dev->irq_enabled));
if (vblwait->request.sequence != seq) {
DRM_DEBUG("waiting on vblank count %d, crtc %d\n",vblwait->request.sequence, crtc);vblank->last_wait = vblwait->request.sequence;DRM_WAIT_ON(ret, vblank->queue, 3 * HZ,(((drm_vblank_count(dev, crtc) -vblwait->request.sequence) <= (1 << 23)) ||!vblank->enabled ||!dev->irq_enabled));}
if (ret != -EINTR) { struct timeval now;
It would be good to have some DRM_DEBUG output for the skip-the-wait case as well, so one can still follow from dmesg output when a client does a drmWaitVblank call even if it is only a query.
We still have DRM_DEBUG("returning %d to client"), as well as the drmIoctl:DRM_DEBUG(ioctl->name), is that not sufficient? -Chris