@@ -311,20 +311,33 @@ static void spin_unlock_wait(spinlock_t *lock)
spin_unlock_irq(lock);
}
+static void active_flush(struct i915_active *ref,
+ struct i915_active_fence *active)
+{
+ struct dma_fence *fence;
+
+ fence = xchg(__active_fence_slot(active), NULL);
+ if (!fence)
+ return;
+
+ spin_lock_irq(fence->lock);
+ __list_del_entry(&active->cb.node);
+ spin_unlock_irq(fence->lock); /* serialise with fence->cb_list */
+ atomic_dec(&ref->count);
+
+ GEM_BUG_ON(!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags));
+}
+
void i915_active_unlock_wait(struct i915_active *ref)
{
if (i915_active_acquire_if_busy(ref)) {
struct active_node *it, *n;
+ /* Wait for all active callbacks */
rcu_read_lock();
- rbtree_postorder_for_each_entry_safe(it, n, &ref->tree, node) {
- struct dma_fence *f;
-
- /* Wait for all active callbacks */
- f = rcu_dereference(it->base.fence);
- if (f)
- spin_unlock_wait(f->lock);
- }
+ active_flush(ref, &ref->excl);
+ rbtree_postorder_for_each_entry_safe(it, n, &ref->tree, node)
+ active_flush(ref, &it->base);
rcu_read_unlock();
i915_active_release(ref);
Due to the ordering of cmpxchg()/dma_fence_signal() inside node_retire(), we must also use the xchg() as our primary memory barrier to flush the outstanding callbacks after expected completion of the i915_active. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/selftests/i915_active.c | 29 ++++++++++++++------ 1 file changed, 21 insertions(+), 8 deletions(-)