diff options
Diffstat (limited to 'linux-core/drm_lock.c')
| -rw-r--r-- | linux-core/drm_lock.c | 96 |
1 files changed, 86 insertions, 10 deletions
diff --git a/linux-core/drm_lock.c b/linux-core/drm_lock.c index a268d8ee..d11c570e 100644 --- a/linux-core/drm_lock.c +++ b/linux-core/drm_lock.c @@ -35,9 +35,12 @@ #include "drmP.h" +#if 0 static int drm_lock_transfer(drm_device_t * dev, __volatile__ unsigned int *lock, unsigned int context); +#endif + static int drm_notifier(void *priv); /** @@ -104,7 +107,7 @@ int drm_lock(struct inode *inode, struct file *filp, __set_current_state(TASK_RUNNING); remove_wait_queue(&dev->lock.lock_queue, &entry); - DRM_DEBUG( "%d %s\n", lock.context, ret ? "interrupted" : "has lock" ); + DRM_DEBUG( "%d %s\n", lock.context, ret ? "interrupted" : "has lock" ); if (ret) return ret; sigemptyset(&dev->sigmask); @@ -152,6 +155,7 @@ int drm_unlock(struct inode *inode, struct file *filp, drm_file_t *priv = filp->private_data; drm_device_t *dev = priv->head->dev; drm_lock_t lock; + unsigned long irqflags; if (copy_from_user(&lock, (drm_lock_t __user *) arg, sizeof(lock))) return -EFAULT; @@ -162,6 +166,16 @@ int drm_unlock(struct inode *inode, struct file *filp, return -EINVAL; } + spin_lock_irqsave(&dev->tasklet_lock, irqflags); + + if (dev->locked_tasklet_func) { + dev->locked_tasklet_func(dev); + + dev->locked_tasklet_func = NULL; + } + + spin_unlock_irqrestore(&dev->tasklet_lock, irqflags); + atomic_inc(&dev->counts[_DRM_STAT_UNLOCKS]); /* kernel_context_switch isn't used by any of the x86 drm @@ -170,12 +184,9 @@ int drm_unlock(struct inode *inode, struct file *filp, if (dev->driver->kernel_context_switch_unlock) dev->driver->kernel_context_switch_unlock(dev); else { - drm_lock_transfer(dev, &dev->lock.hw_lock->lock, - DRM_KERNEL_CONTEXT); - if (drm_lock_free(dev, &dev->lock.hw_lock->lock, - DRM_KERNEL_CONTEXT)) { - DRM_ERROR("\n"); + lock.context)) { + /* FIXME: Should really bail out here. */ } } @@ -201,7 +212,7 @@ int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context) if (old & _DRM_LOCK_HELD) new = old | _DRM_LOCK_CONT; else - new = context | _DRM_LOCK_HELD; + new = context | _DRM_LOCK_HELD | _DRM_LOCK_CONT; prev = cmpxchg(lock, old, new); } while (prev != old); if (_DRM_LOCKING_CONTEXT(old) == context) { @@ -213,13 +224,14 @@ int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context) return 0; } } - if (new == (context | _DRM_LOCK_HELD)) { + if (new == (context | _DRM_LOCK_HELD | _DRM_LOCK_CONT)) { /* Have lock */ return 1; } return 0; } +#if 0 /** * This takes a lock forcibly and hands it to context. Should ONLY be used * inside *_unlock to give lock to kernel before calling *_dma_schedule. @@ -246,6 +258,7 @@ static int drm_lock_transfer(drm_device_t * dev, } while (prev != old); return 1; } +#endif /** * Free lock. @@ -263,12 +276,12 @@ int drm_lock_free(drm_device_t * dev, { unsigned int old, new, prev; - dev->lock.filp = NULL; do { old = *lock; - new = 0; + new = _DRM_LOCKING_CONTEXT(old); prev = cmpxchg(lock, old, new); } while (prev != old); + if (_DRM_LOCK_IS_HELD(old) && _DRM_LOCKING_CONTEXT(old) != context) { DRM_ERROR("%d freed heavyweight lock held by %d\n", context, _DRM_LOCKING_CONTEXT(old)); @@ -308,3 +321,66 @@ static int drm_notifier(void *priv) } while (prev != old); return 0; } + +/* + * Can be used by drivers to take the hardware lock if necessary. + * (Waiting for idle before reclaiming buffers etc.) + */ + +int drm_i_have_hw_lock(struct file *filp) +{ + DRM_DEVICE; + + return (priv->lock_count && dev->lock.hw_lock && + _DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) && + dev->lock.filp == filp); +} + +EXPORT_SYMBOL(drm_i_have_hw_lock); + +int drm_kernel_take_hw_lock(struct file *filp) +{ + DRM_DEVICE; + + int ret = 0; + unsigned long _end = jiffies + 3*DRM_HZ; + + if (!drm_i_have_hw_lock(filp)) { + + DECLARE_WAITQUEUE(entry, current); + + add_wait_queue(&dev->lock.lock_queue, &entry); + for (;;) { + __set_current_state(TASK_INTERRUPTIBLE); + if (!dev->lock.hw_lock) { + /* Device has been unregistered */ + ret = -EINTR; + break; + } + if (drm_lock_take(&dev->lock.hw_lock->lock, + DRM_KERNEL_CONTEXT)) { + dev->lock.filp = filp; + dev->lock.lock_time = jiffies; + atomic_inc(&dev->counts[_DRM_STAT_LOCKS]); + break; /* Got lock */ + } + /* Contention */ + if (time_after_eq(jiffies,_end)) { + ret = -EBUSY; + break; + } + + schedule_timeout(1); + if (signal_pending(current)) { + ret = -ERESTARTSYS; + break; + } + } + __set_current_state(TASK_RUNNING); + remove_wait_queue(&dev->lock.lock_queue, &entry); + } + return ret; +} + +EXPORT_SYMBOL(drm_kernel_take_hw_lock); + |