drm/ttm: alter cpu_writers to return -EBUSY in ttm_execbuf_util reservations

This is similar to other platforms that don't allow command submission
to buffers locked on the cpu.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Maarten Lankhorst 2012-11-06 14:39:43 +01:00 committed by Dave Airlie
parent 6c1e963cc5
commit 654aa79259
4 changed files with 5 additions and 32 deletions

View File

@ -1053,16 +1053,6 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo,
}
EXPORT_SYMBOL(ttm_bo_mem_space);
int ttm_bo_wait_cpu(struct ttm_buffer_object *bo, bool no_wait)
{
if ((atomic_read(&bo->cpu_writers) > 0) && no_wait)
return -EBUSY;
return wait_event_interruptible(bo->event_queue,
atomic_read(&bo->cpu_writers) == 0);
}
EXPORT_SYMBOL(ttm_bo_wait_cpu);
int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
struct ttm_placement *placement,
bool interruptible, bool no_wait_reserve,
@ -1788,8 +1778,7 @@ EXPORT_SYMBOL(ttm_bo_synccpu_write_grab);
void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo)
{
if (atomic_dec_and_test(&bo->cpu_writers))
wake_up_all(&bo->event_queue);
atomic_dec(&bo->cpu_writers);
}
EXPORT_SYMBOL(ttm_bo_synccpu_write_release);

View File

@ -185,10 +185,7 @@ int ttm_eu_reserve_buffers(struct list_head *list)
ttm_eu_backoff_reservation_locked(list);
spin_unlock(&glob->lru_lock);
ttm_eu_list_ref_sub(list);
ret = ttm_bo_wait_cpu(bo, false);
if (ret)
return ret;
goto retry;
return -EBUSY;
}
}

View File

@ -424,8 +424,9 @@ extern void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev,
* @no_wait: Return immediately if buffer is busy.
*
* Synchronizes a buffer object for CPU RW access. This means
* blocking command submission that affects the buffer and
* waiting for buffer idle. This lock is recursive.
* command submission that affects the buffer will return -EBUSY
* until ttm_bo_synccpu_write_release is called.
*
* Returns
* -EBUSY if the buffer is busy and no_wait is true.
* -ERESTARTSYS if interrupted by a signal.

View File

@ -726,20 +726,6 @@ extern void ttm_bo_mem_put(struct ttm_buffer_object *bo,
extern void ttm_bo_mem_put_locked(struct ttm_buffer_object *bo,
struct ttm_mem_reg *mem);
/**
* ttm_bo_wait_for_cpu
*
* @bo: Pointer to a struct ttm_buffer_object.
* @no_wait: Don't sleep while waiting.
*
* Wait until a buffer object is no longer sync'ed for CPU access.
* Returns:
* -EBUSY: Buffer object was sync'ed for CPU access. (only if no_wait == 1).
* -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
*/
extern int ttm_bo_wait_cpu(struct ttm_buffer_object *bo, bool no_wait);
extern void ttm_bo_global_release(struct drm_global_reference *ref);
extern int ttm_bo_global_init(struct drm_global_reference *ref);