#include "drmP.h"
-static int drm_lock_transfer(drm_device_t * dev,
- __volatile__ unsigned int *lock,
- unsigned int context);
static int drm_notifier(void *priv);
/**
* Lock ioctl.
*
* \param inode device inode.
- * \param filp file pointer.
+ * \param file_priv DRM file private.
* \param cmd command.
* \param arg user argument, pointing to a drm_lock structure.
* \return zero on success or negative number on failure.
*
* Add the current task to the lock wait queue, and attempt to take to lock.
*/
-int drm_lock(struct inode *inode, struct file *filp,
- unsigned int cmd, unsigned long arg)
+int drm_lock(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
- drm_file_t *priv = filp->private_data;
- drm_device_t *dev = priv->head->dev;
DECLARE_WAITQUEUE(entry, current);
- drm_lock_t lock;
+ struct drm_lock *lock = data;
int ret = 0;
- ++priv->lock_count;
+ ++file_priv->lock_count;
- if (copy_from_user(&lock, (drm_lock_t __user *) arg, sizeof(lock)))
- return -EFAULT;
-
- if (lock.context == DRM_KERNEL_CONTEXT) {
+ if (lock->context == DRM_KERNEL_CONTEXT) {
DRM_ERROR("Process %d using kernel context %d\n",
- current->pid, lock.context);
+ task_pid_nr(current), lock->context);
return -EINVAL;
}
DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n",
- lock.context, current->pid,
- dev->lock.hw_lock->lock, lock.flags);
+ lock->context, task_pid_nr(current),
+ dev->lock.hw_lock->lock, lock->flags);
if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE))
- if (lock.context < 0)
+ if (lock->context < 0)
return -EINVAL;
add_wait_queue(&dev->lock.lock_queue, &entry);
+ spin_lock(&dev->lock.spinlock);
+ dev->lock.user_waiters++;
+ spin_unlock(&dev->lock.spinlock);
for (;;) {
__set_current_state(TASK_INTERRUPTIBLE);
if (!dev->lock.hw_lock) {
ret = -EINTR;
break;
}
- if (drm_lock_take(&dev->lock.hw_lock->lock, lock.context)) {
- dev->lock.filp = filp;
+ if (drm_lock_take(&dev->lock, lock->context)) {
+ dev->lock.file_priv = file_priv;
dev->lock.lock_time = jiffies;
atomic_inc(&dev->counts[_DRM_STAT_LOCKS]);
break; /* Got lock */
break;
}
}
+ spin_lock(&dev->lock.spinlock);
+ dev->lock.user_waiters--;
+ spin_unlock(&dev->lock.spinlock);
__set_current_state(TASK_RUNNING);
remove_wait_queue(&dev->lock.lock_queue, &entry);
- DRM_DEBUG("%d %s\n", lock.context, ret ? "interrupted" : "has lock");
- if (ret)
- return ret;
+ DRM_DEBUG("%d %s\n", lock->context,
+ ret ? "interrupted" : "has lock");
+ if (ret) return ret;
sigemptyset(&dev->sigmask);
sigaddset(&dev->sigmask, SIGSTOP);
sigaddset(&dev->sigmask, SIGTSTP);
sigaddset(&dev->sigmask, SIGTTIN);
sigaddset(&dev->sigmask, SIGTTOU);
- dev->sigdata.context = lock.context;
+ dev->sigdata.context = lock->context;
dev->sigdata.lock = dev->lock.hw_lock;
block_all_signals(drm_notifier, &dev->sigdata, &dev->sigmask);
- if (dev->driver->dma_ready && (lock.flags & _DRM_LOCK_READY))
+ if (dev->driver->dma_ready && (lock->flags & _DRM_LOCK_READY))
dev->driver->dma_ready(dev);
- if (dev->driver->dma_quiescent && (lock.flags & _DRM_LOCK_QUIESCENT)) {
+ if (dev->driver->dma_quiescent && (lock->flags & _DRM_LOCK_QUIESCENT))
+ {
if (dev->driver->dma_quiescent(dev)) {
- DRM_DEBUG("%d waiting for DMA quiescent\n", lock.context);
- return DRM_ERR(EBUSY);
+ DRM_DEBUG("%d waiting for DMA quiescent\n",
+ lock->context);
+ return -EBUSY;
}
}
- /* dev->driver->kernel_context_switch isn't used by any of the x86
- * drivers but is used by the Sparc driver.
- */
if (dev->driver->kernel_context_switch &&
- dev->last_context != lock.context) {
+ dev->last_context != lock->context) {
dev->driver->kernel_context_switch(dev, dev->last_context,
- lock.context);
+ lock->context);
}
+
return 0;
}
* Unlock ioctl.
*
* \param inode device inode.
- * \param filp file pointer.
+ * \param file_priv DRM file private.
* \param cmd command.
* \param arg user argument, pointing to a drm_lock structure.
* \return zero on success or negative number on failure.
*
* Transfer and free the lock.
*/
-int drm_unlock(struct inode *inode, struct file *filp,
- unsigned int cmd, unsigned long arg)
+int drm_unlock(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
- drm_file_t *priv = filp->private_data;
- drm_device_t *dev = priv->head->dev;
- drm_lock_t lock;
+ struct drm_lock *lock = data;
unsigned long irqflags;
- if (copy_from_user(&lock, (drm_lock_t __user *) arg, sizeof(lock)))
- return -EFAULT;
-
- if (lock.context == DRM_KERNEL_CONTEXT) {
+ if (lock->context == DRM_KERNEL_CONTEXT) {
DRM_ERROR("Process %d using kernel context %d\n",
- current->pid, lock.context);
+ task_pid_nr(current), lock->context);
return -EINVAL;
}
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");
+ if (drm_lock_free(&dev->lock,lock->context)) {
+ /* FIXME: Should really bail out here. */
}
}
*
* Attempt to mark the lock as held by the given context, via the \p cmpxchg instruction.
*/
-int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context)
+int drm_lock_take(struct drm_lock_data *lock_data,
+ unsigned int context)
{
unsigned int old, new, prev;
+ volatile unsigned int *lock = &lock_data->hw_lock->lock;
+ spin_lock(&lock_data->spinlock);
do {
old = *lock;
if (old & _DRM_LOCK_HELD)
new = old | _DRM_LOCK_CONT;
- else
- new = context | _DRM_LOCK_HELD;
+ else {
+ new = context | _DRM_LOCK_HELD |
+ ((lock_data->user_waiters + lock_data->kernel_waiters > 1) ?
+ _DRM_LOCK_CONT : 0);
+ }
prev = cmpxchg(lock, old, new);
} while (prev != old);
+ spin_unlock(&lock_data->spinlock);
+
if (_DRM_LOCKING_CONTEXT(old) == context) {
if (old & _DRM_LOCK_HELD) {
if (context != DRM_KERNEL_CONTEXT) {
return 0;
}
}
- if (new == (context | _DRM_LOCK_HELD)) {
+
+ if ((_DRM_LOCKING_CONTEXT(new)) == context && (new & _DRM_LOCK_HELD)) {
/* Have lock */
return 1;
}
* Resets the lock file pointer.
* Marks the lock as held by the given context, via the \p cmpxchg instruction.
*/
-static int drm_lock_transfer(drm_device_t * dev,
- __volatile__ unsigned int *lock,
+static int drm_lock_transfer(struct drm_lock_data *lock_data,
unsigned int context)
{
unsigned int old, new, prev;
+ volatile unsigned int *lock = &lock_data->hw_lock->lock;
- dev->lock.filp = NULL;
+ lock_data->file_priv = NULL;
do {
old = *lock;
new = context | _DRM_LOCK_HELD;
* Marks the lock as not held, via the \p cmpxchg instruction. Wakes any task
* waiting on the lock queue.
*/
-int drm_lock_free(drm_device_t * dev,
- __volatile__ unsigned int *lock, unsigned int context)
+int drm_lock_free(struct drm_lock_data *lock_data, unsigned int context)
{
unsigned int old, new, prev;
+ volatile unsigned int *lock = &lock_data->hw_lock->lock;
+
+ spin_lock(&lock_data->spinlock);
+ if (lock_data->kernel_waiters != 0) {
+ drm_lock_transfer(lock_data, 0);
+ lock_data->idle_has_lock = 1;
+ spin_unlock(&lock_data->spinlock);
+ return 1;
+ }
+ spin_unlock(&lock_data->spinlock);
- 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));
return 1;
}
- wake_up_interruptible(&dev->lock.lock_queue);
+ wake_up_interruptible(&lock_data->lock_queue);
return 0;
}
*/
static int drm_notifier(void *priv)
{
- drm_sigdata_t *s = (drm_sigdata_t *) priv;
+ struct drm_sigdata *s = (struct drm_sigdata *) priv;
unsigned int old, new, prev;
/* Allow signal delivery if lock isn't held */
} while (prev != old);
return 0;
}
+
+/**
+ * This function returns immediately and takes the hw lock
+ * with the kernel context if it is free, otherwise it gets the highest priority when and if
+ * it is eventually released.
+ *
+ * This guarantees that the kernel will _eventually_ have the lock _unless_ it is held
+ * by a blocked process. (In the latter case an explicit wait for the hardware lock would cause
+ * a deadlock, which is why the "idlelock" was invented).
+ *
+ * This should be sufficient to wait for GPU idle without
+ * having to worry about starvation.
+ */
+
+void drm_idlelock_take(struct drm_lock_data *lock_data)
+{
+ int ret = 0;
+
+ spin_lock(&lock_data->spinlock);
+ lock_data->kernel_waiters++;
+ if (!lock_data->idle_has_lock) {
+
+ spin_unlock(&lock_data->spinlock);
+ ret = drm_lock_take(lock_data, DRM_KERNEL_CONTEXT);
+ spin_lock(&lock_data->spinlock);
+
+ if (ret == 1)
+ lock_data->idle_has_lock = 1;
+ }
+ spin_unlock(&lock_data->spinlock);
+}
+EXPORT_SYMBOL(drm_idlelock_take);
+
+void drm_idlelock_release(struct drm_lock_data *lock_data)
+{
+ unsigned int old, prev;
+ volatile unsigned int *lock = &lock_data->hw_lock->lock;
+
+ spin_lock(&lock_data->spinlock);
+ if (--lock_data->kernel_waiters == 0) {
+ if (lock_data->idle_has_lock) {
+ do {
+ old = *lock;
+ prev = cmpxchg(lock, old, DRM_KERNEL_CONTEXT);
+ } while (prev != old);
+ wake_up_interruptible(&lock_data->lock_queue);
+ lock_data->idle_has_lock = 0;
+ }
+ }
+ spin_unlock(&lock_data->spinlock);
+}
+EXPORT_SYMBOL(drm_idlelock_release);
+
+
+int drm_i_have_hw_lock(struct drm_device *dev, struct drm_file *file_priv)
+{
+ return (file_priv->lock_count && dev->lock.hw_lock &&
+ _DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) &&
+ dev->lock.file_priv == file_priv);
+}
+
+EXPORT_SYMBOL(drm_i_have_hw_lock);
projects / linux-2.6-omap-h63xx.git / blobdiff