diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2009-02-19 14:48:22 +0000 |
|---|---|---|
| committer | Dave Airlie <airlied@linux.ie> | 2009-02-25 14:45:50 +1000 |
| commit | b3f5e7329df1a508ac58ebe7509fb7a47b9eab6a (patch) | |
| tree | 26053313cadc6914662e88de0af2e2fe04d80913 /drivers/gpu/drm/drm_irq.c | |
| parent | 7bec756c74b1a5079d5074144bb77a6b3e7d7783 (diff) | |
| download | lwn-b3f5e7329df1a508ac58ebe7509fb7a47b9eab6a.tar.gz lwn-b3f5e7329df1a508ac58ebe7509fb7a47b9eab6a.zip | |
drm: Correct unbalanced drm_vblank_put() during mode setting.
The first time we install a mode, the vblank will be disabled for a pipe
and so drm_vblank_get() in drm_vblank_pre_modeset() will fail. As we
unconditionally call drm_vblank_put() afterwards, the vblank reference
counter becomes unbalanced.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>
Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
| -rw-r--r-- | drivers/gpu/drm/drm_irq.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 3795dbc0f50c..93e677a481f5 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -435,6 +435,8 @@ EXPORT_SYMBOL(drm_vblank_get); */ void drm_vblank_put(struct drm_device *dev, int crtc) { + BUG_ON (atomic_read (&dev->vblank_refcount[crtc]) == 0); + /* Last user schedules interrupt disable */ if (atomic_dec_and_test(&dev->vblank_refcount[crtc])) mod_timer(&dev->vblank_disable_timer, jiffies + 5*DRM_HZ); @@ -460,8 +462,9 @@ void drm_vblank_pre_modeset(struct drm_device *dev, int crtc) * so that interrupts remain enabled in the interim. */ if (!dev->vblank_inmodeset[crtc]) { - dev->vblank_inmodeset[crtc] = 1; - drm_vblank_get(dev, crtc); + dev->vblank_inmodeset[crtc] = 0x1; + if (drm_vblank_get(dev, crtc) == 0) + dev->vblank_inmodeset[crtc] |= 0x2; } } EXPORT_SYMBOL(drm_vblank_pre_modeset); @@ -473,9 +476,12 @@ void drm_vblank_post_modeset(struct drm_device *dev, int crtc) if (dev->vblank_inmodeset[crtc]) { spin_lock_irqsave(&dev->vbl_lock, irqflags); dev->vblank_disable_allowed = 1; - dev->vblank_inmodeset[crtc] = 0; spin_unlock_irqrestore(&dev->vbl_lock, irqflags); - drm_vblank_put(dev, crtc); + + if (dev->vblank_inmodeset[crtc] & 0x2) + drm_vblank_put(dev, crtc); + + dev->vblank_inmodeset[crtc] = 0; } } EXPORT_SYMBOL(drm_vblank_post_modeset); |