From dc1336ff4fe08ae7cfe8301bfd7f0b2cfd31d20a Mon Sep 17 00:00:00 2001 From: Jesse Barnes Date: Tue, 6 Jan 2009 10:21:24 -0800 Subject: [PATCH] drm/i915: set vblank enabled flag correctly across IRQ install/uninstall In the absence of kernel mode setting, many drivers disable IRQs across VT switch. The core DRM vblank code is missing a check for this case however; even after IRQ disable, the vblank code will still have the vblank_enabled flag set, so unless we track the fact that they're disabled at IRQ uninstall time, when we VT switch back in we won't actually re-enable them, which means any apps waiting on vblank before the switch will hang. This patch does that and also adds a sanity check to the wait condition to look for the irq_enabled flag in general, as well as adding a wakeup to the IRQ uninstall path. Fixes fdo bug #18879 with compiz hangs at VT switch. Signed-off-by: Jesse Barnes Signed-off-by: Eric Anholt Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_irq.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 724e505873c..477caa1b1e4 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -267,7 +267,8 @@ EXPORT_SYMBOL(drm_irq_install); */ int drm_irq_uninstall(struct drm_device * dev) { - int irq_enabled; + unsigned long irqflags; + int irq_enabled, i; if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) return -EINVAL; @@ -277,6 +278,16 @@ int drm_irq_uninstall(struct drm_device * dev) dev->irq_enabled = 0; mutex_unlock(&dev->struct_mutex); + /* + * 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; + } + spin_unlock_irqrestore(&dev->vbl_lock, irqflags); + if (!irq_enabled) return -EINVAL; @@ -652,8 +663,9 @@ int drm_wait_vblank(struct drm_device *dev, void *data, vblwait->request.sequence, crtc); dev->last_vblank_wait[crtc] = vblwait->request.sequence; DRM_WAIT_ON(ret, dev->vbl_queue[crtc], 3 * DRM_HZ, - ((drm_vblank_count(dev, crtc) - - vblwait->request.sequence) <= (1 << 23))); + (((drm_vblank_count(dev, crtc) - + vblwait->request.sequence) <= (1 << 23)) || + !dev->irq_enabled)); if (ret != -EINTR) { struct timeval now; -- 2.41.1