diff options
Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
| -rw-r--r-- | drivers/gpu/drm/drm_irq.c | 31 |
1 files changed, 15 insertions, 16 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index cb3794a00f9..44a5d0ad8b7 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -110,10 +110,7 @@ static void vblank_disable_and_save(struct drm_device *dev, int crtc) /* Prevent vblank irq processing while disabling vblank irqs, * so no updates of timestamps or count can happen after we've * disabled. Needed to prevent races in case of delayed irq's. - * Disable preemption, so vblank_time_lock is held as short as - * possible, even under a kernel with PREEMPT_RT patches. */ - preempt_disable(); spin_lock_irqsave(&dev->vblank_time_lock, irqflags); dev->driver->disable_vblank(dev, crtc); @@ -164,7 +161,6 @@ static void vblank_disable_and_save(struct drm_device *dev, int crtc) clear_vblank_timestamps(dev, crtc); spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags); - preempt_enable(); } static void vblank_disable_fn(unsigned long arg) @@ -407,13 +403,16 @@ int drm_irq_uninstall(struct drm_device *dev) /* * Wake up any waiters so they don't hang. */ - spin_lock_irqsave(&dev->vbl_lock, irqflags); - for (i = 0; i < dev->num_crtcs; i++) { - DRM_WAKEUP(&dev->vbl_queue[i]); - dev->vblank_enabled[i] = 0; - dev->last_vblank[i] = dev->driver->get_vblank_counter(dev, i); + if (dev->num_crtcs) { + spin_lock_irqsave(&dev->vbl_lock, irqflags); + for (i = 0; i < dev->num_crtcs; i++) { + DRM_WAKEUP(&dev->vbl_queue[i]); + dev->vblank_enabled[i] = 0; + dev->last_vblank[i] = + dev->driver->get_vblank_counter(dev, i); + } + spin_unlock_irqrestore(&dev->vbl_lock, irqflags); } - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); if (!irq_enabled) return -EINVAL; @@ -886,10 +885,6 @@ int drm_vblank_get(struct drm_device *dev, int crtc) spin_lock_irqsave(&dev->vbl_lock, irqflags); /* Going from 0->1 means we have to enable interrupts again */ if (atomic_add_return(1, &dev->vblank_refcount[crtc]) == 1) { - /* Disable preemption while holding vblank_time_lock. Do - * it explicitely to guard against PREEMPT_RT kernel. - */ - preempt_disable(); spin_lock_irqsave(&dev->vblank_time_lock, irqflags2); if (!dev->vblank_enabled[crtc]) { /* Enable vblank irqs under vblank_time_lock protection. @@ -909,7 +904,6 @@ int drm_vblank_get(struct drm_device *dev, int crtc) } } spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags2); - preempt_enable(); } else { if (!dev->vblank_enabled[crtc]) { atomic_dec(&dev->vblank_refcount[crtc]); @@ -1125,6 +1119,7 @@ static int drm_queue_vblank_event(struct drm_device *dev, int pipe, trace_drm_vblank_event_delivered(current->pid, pipe, vblwait->request.sequence); } else { + /* drm_handle_vblank_events will call drm_vblank_put */ list_add_tail(&e->base.link, &dev->vblank_event_list); vblwait->reply.sequence = vblwait->request.sequence; } @@ -1205,8 +1200,12 @@ int drm_wait_vblank(struct drm_device *dev, void *data, goto done; } - if (flags & _DRM_VBLANK_EVENT) + if (flags & _DRM_VBLANK_EVENT) { + /* must hold on to the vblank ref until the event fires + * drm_vblank_put will be called asynchronously + */ return drm_queue_vblank_event(dev, crtc, vblwait, file_priv); + } if ((flags & _DRM_VBLANK_NEXTONMISS) && (seq - vblwait->request.sequence) <= (1<<23)) { |