1 files changed, 371 insertions, 250 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c
index 4bd36a354fbe..11f5f402d22c 100644
--- a/drivers/gpu/drm/radeon/radeon_fence.c
+++ b/drivers/gpu/drm/radeon/radeon_fence.c
@@ -63,98 +63,82 @@ static u32 radeon_fence_read(struct radeon_device *rdev, int ring)
 
 int radeon_fence_emit(struct radeon_device *rdev, struct radeon_fence *fence)
 {
-	unsigned long irq_flags;
-
-	write_lock_irqsave(&rdev->fence_lock, irq_flags);
-	if (fence->emitted) {
-		write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
+	/* we are protected by the ring emission mutex */
+	if (fence->seq && fence->seq < RADEON_FENCE_NOTEMITED_SEQ) {
 		return 0;
 	}
-	fence->seq = atomic_add_return(1, &rdev->fence_drv[fence->ring].seq);
-	if (!rdev->ring[fence->ring].ready)
-		/* FIXME: cp is not running assume everythings is done right
-		 * away
-		 */
-		radeon_fence_write(rdev, fence->seq, fence->ring);
-	else
-		radeon_fence_ring_emit(rdev, fence->ring, fence);
-
+	fence->seq = ++rdev->fence_drv[fence->ring].seq;
+	radeon_fence_ring_emit(rdev, fence->ring, fence);
 	trace_radeon_fence_emit(rdev->ddev, fence->seq);
-	fence->emitted = true;
-	list_move_tail(&fence->list, &rdev->fence_drv[fence->ring].emitted);
-	write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
 	return 0;
 }
 
-static bool radeon_fence_poll_locked(struct radeon_device *rdev, int ring)
+void radeon_fence_process(struct radeon_device *rdev, int ring)
 {
-	struct radeon_fence *fence;
-	struct list_head *i, *n;
-	uint32_t seq;
+	uint64_t seq, last_seq;
+	unsigned count_loop = 0;
 	bool wake = false;
-	unsigned long cjiffies;
 
-	seq = radeon_fence_read(rdev, ring);
-	if (seq != rdev->fence_drv[ring].last_seq) {
-		rdev->fence_drv[ring].last_seq = seq;
-		rdev->fence_drv[ring].last_jiffies = jiffies;
-		rdev->fence_drv[ring].last_timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
-	} else {
-		cjiffies = jiffies;
-		if (time_after(cjiffies, rdev->fence_drv[ring].last_jiffies)) {
-			cjiffies -= rdev->fence_drv[ring].last_jiffies;
-			if (time_after(rdev->fence_drv[ring].last_timeout, cjiffies)) {
-				/* update the timeout */
-				rdev->fence_drv[ring].last_timeout -= cjiffies;
-			} else {
-				/* the 500ms timeout is elapsed we should test
-				 * for GPU lockup
-				 */
-				rdev->fence_drv[ring].last_timeout = 1;
-			}
-		} else {
-			/* wrap around update last jiffies, we will just wait
-			 * a little longer
-			 */
-			rdev->fence_drv[ring].last_jiffies = cjiffies;
+	/* Note there is a scenario here for an infinite loop but it's
+	 * very unlikely to happen. For it to happen, the current polling
+	 * process need to be interrupted by another process and another
+	 * process needs to update the last_seq btw the atomic read and
+	 * xchg of the current process.
+	 *
+	 * More over for this to go in infinite loop there need to be
+	 * continuously new fence signaled ie radeon_fence_read needs
+	 * to return a different value each time for both the currently
+	 * polling process and the other process that xchg the last_seq
+	 * btw atomic read and xchg of the current process. And the
+	 * value the other process set as last seq must be higher than
+	 * the seq value we just read. Which means that current process
+	 * need to be interrupted after radeon_fence_read and before
+	 * atomic xchg.
+	 *
+	 * To be even more safe we count the number of time we loop and
+	 * we bail after 10 loop just accepting the fact that we might
+	 * have temporarly set the last_seq not to the true real last
+	 * seq but to an older one.
+	 */
+	last_seq = atomic64_read(&rdev->fence_drv[ring].last_seq);
+	do {
+		seq = radeon_fence_read(rdev, ring);
+		seq |= last_seq & 0xffffffff00000000LL;
+		if (seq < last_seq) {
+			seq += 0x100000000LL;
 		}
-		return false;
-	}
-	n = NULL;
-	list_for_each(i, &rdev->fence_drv[ring].emitted) {
-		fence = list_entry(i, struct radeon_fence, list);
-		if (fence->seq == seq) {
-			n = i;
+
+		if (seq == last_seq) {
 			break;
 		}
-	}
-	/* all fence previous to this one are considered as signaled */
-	if (n) {
-		i = n;
-		do {
-			n = i->prev;
-			list_move_tail(i, &rdev->fence_drv[ring].signaled);
-			fence = list_entry(i, struct radeon_fence, list);
-			fence->signaled = true;
-			i = n;
-		} while (i != &rdev->fence_drv[ring].emitted);
+		/* If we loop over we don't want to return without
+		 * checking if a fence is signaled as it means that the
+		 * seq we just read is different from the previous on.
+		 */
 		wake = true;
+		last_seq = seq;
+		if ((count_loop++) > 10) {
+			/* We looped over too many time leave with the
+			 * fact that we might have set an older fence
+			 * seq then the current real last seq as signaled
+			 * by the hw.
+			 */
+			break;
+		}
+	} while (atomic64_xchg(&rdev->fence_drv[ring].last_seq, seq) > seq);
+
+	if (wake) {
+		rdev->fence_drv[ring].last_activity = jiffies;
+		wake_up_all(&rdev->fence_queue);
 	}
-	return wake;
 }
 
 static void radeon_fence_destroy(struct kref *kref)
 {
-	unsigned long irq_flags;
-        struct radeon_fence *fence;
+	struct radeon_fence *fence;
 
 	fence = container_of(kref, struct radeon_fence, kref);
-	write_lock_irqsave(&fence->rdev->fence_lock, irq_flags);
-	list_del(&fence->list);
-	fence->emitted = false;
-	write_unlock_irqrestore(&fence->rdev->fence_lock, irq_flags);
-	if (fence->semaphore)
-		radeon_semaphore_free(fence->rdev, fence->semaphore);
+	fence->seq = RADEON_FENCE_NOTEMITED_SEQ;
 	kfree(fence);
 }
 
@@ -162,171 +146,342 @@ int radeon_fence_create(struct radeon_device *rdev,
 			struct radeon_fence **fence,
 			int ring)
 {
-	unsigned long irq_flags;
-
 	*fence = kmalloc(sizeof(struct radeon_fence), GFP_KERNEL);
 	if ((*fence) == NULL) {
 		return -ENOMEM;
 	}
 	kref_init(&((*fence)->kref));
 	(*fence)->rdev = rdev;
-	(*fence)->emitted = false;
-	(*fence)->signaled = false;
-	(*fence)->seq = 0;
+	(*fence)->seq = RADEON_FENCE_NOTEMITED_SEQ;
 	(*fence)->ring = ring;
-	(*fence)->semaphore = NULL;
-	INIT_LIST_HEAD(&(*fence)->list);
-
-	write_lock_irqsave(&rdev->fence_lock, irq_flags);
-	list_add_tail(&(*fence)->list, &rdev->fence_drv[ring].created);
-	write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
 	return 0;
 }
 
-bool radeon_fence_signaled(struct radeon_fence *fence)
+static bool radeon_fence_seq_signaled(struct radeon_device *rdev,
+				      u64 seq, unsigned ring)
 {
-	unsigned long irq_flags;
-	bool signaled = false;
-
-	if (!fence)
+	if (atomic64_read(&rdev->fence_drv[ring].last_seq) >= seq) {
 		return true;
-
-	if (fence->rdev->gpu_lockup)
+	}
+	/* poll new last sequence at least once */
+	radeon_fence_process(rdev, ring);
+	if (atomic64_read(&rdev->fence_drv[ring].last_seq) >= seq) {
 		return true;
+	}
+	return false;
+}
 
-	write_lock_irqsave(&fence->rdev->fence_lock, irq_flags);
-	signaled = fence->signaled;
-	/* if we are shuting down report all fence as signaled */
-	if (fence->rdev->shutdown) {
-		signaled = true;
+bool radeon_fence_signaled(struct radeon_fence *fence)
+{
+	if (!fence) {
+		return true;
 	}
-	if (!fence->emitted) {
+	if (fence->seq == RADEON_FENCE_NOTEMITED_SEQ) {
 		WARN(1, "Querying an unemitted fence : %p !\n", fence);
-		signaled = true;
+		return true;
 	}
-	if (!signaled) {
-		radeon_fence_poll_locked(fence->rdev, fence->ring);
-		signaled = fence->signaled;
+	if (fence->seq == RADEON_FENCE_SIGNALED_SEQ) {
+		return true;
+	}
+	if (radeon_fence_seq_signaled(fence->rdev, fence->seq, fence->ring)) {
+		fence->seq = RADEON_FENCE_SIGNALED_SEQ;
+		return true;
 	}
-	write_unlock_irqrestore(&fence->rdev->fence_lock, irq_flags);
-	return signaled;
+	return false;
+}
+
+static int radeon_fence_wait_seq(struct radeon_device *rdev, u64 target_seq,
+				 unsigned ring, bool intr, bool lock_ring)
+{
+	unsigned long timeout, last_activity;
+	uint64_t seq;
+	unsigned i;
+	bool signaled;
+	int r;
+
+	while (target_seq > atomic64_read(&rdev->fence_drv[ring].last_seq)) {
+		if (!rdev->ring[ring].ready) {
+			return -EBUSY;
+		}
+
+		timeout = jiffies - RADEON_FENCE_JIFFIES_TIMEOUT;
+		if (time_after(rdev->fence_drv[ring].last_activity, timeout)) {
+			/* the normal case, timeout is somewhere before last_activity */
+			timeout = rdev->fence_drv[ring].last_activity - timeout;
+		} else {
+			/* either jiffies wrapped around, or no fence was signaled in the last 500ms
+			 * anyway we will just wait for the minimum amount and then check for a lockup
+			 */
+			timeout = 1;
+		}
+		seq = atomic64_read(&rdev->fence_drv[ring].last_seq);
+		/* Save current last activity valuee, used to check for GPU lockups */
+		last_activity = rdev->fence_drv[ring].last_activity;
+
+		trace_radeon_fence_wait_begin(rdev->ddev, seq);
+		radeon_irq_kms_sw_irq_get(rdev, ring);
+		if (intr) {
+			r = wait_event_interruptible_timeout(rdev->fence_queue,
+				(signaled = radeon_fence_seq_signaled(rdev, target_seq, ring)),
+				timeout);
+                } else {
+			r = wait_event_timeout(rdev->fence_queue,
+				(signaled = radeon_fence_seq_signaled(rdev, target_seq, ring)),
+				timeout);
+		}
+		radeon_irq_kms_sw_irq_put(rdev, ring);
+		if (unlikely(r < 0)) {
+			return r;
+		}
+		trace_radeon_fence_wait_end(rdev->ddev, seq);
+
+		if (unlikely(!signaled)) {
+			/* we were interrupted for some reason and fence
+			 * isn't signaled yet, resume waiting */
+			if (r) {
+				continue;
+			}
+
+			/* check if sequence value has changed since last_activity */
+			if (seq != atomic64_read(&rdev->fence_drv[ring].last_seq)) {
+				continue;
+			}
+
+			if (lock_ring) {
+				mutex_lock(&rdev->ring_lock);
+			}
+
+			/* test if somebody else has already decided that this is a lockup */
+			if (last_activity != rdev->fence_drv[ring].last_activity) {
+				if (lock_ring) {
+					mutex_unlock(&rdev->ring_lock);
+				}
+				continue;
+			}
+
+			if (radeon_ring_is_lockup(rdev, ring, &rdev->ring[ring])) {
+				/* good news we believe it's a lockup */
+				dev_warn(rdev->dev, "GPU lockup (waiting for 0x%016llx last fence id 0x%016llx)\n",
+					 target_seq, seq);
+
+				/* change last activity so nobody else think there is a lockup */
+				for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+					rdev->fence_drv[i].last_activity = jiffies;
+				}
+
+				/* mark the ring as not ready any more */
+				rdev->ring[ring].ready = false;
+				if (lock_ring) {
+					mutex_unlock(&rdev->ring_lock);
+				}
+				return -EDEADLK;
+			}
+
+			if (lock_ring) {
+				mutex_unlock(&rdev->ring_lock);
+			}
+		}
+	}
+	return 0;
 }
 
 int radeon_fence_wait(struct radeon_fence *fence, bool intr)
 {
-	struct radeon_device *rdev;
-	unsigned long irq_flags, timeout;
-	u32 seq;
 	int r;
 
 	if (fence == NULL) {
 		WARN(1, "Querying an invalid fence : %p !\n", fence);
-		return 0;
+		return -EINVAL;
 	}
-	rdev = fence->rdev;
-	if (radeon_fence_signaled(fence)) {
-		return 0;
+
+	r = radeon_fence_wait_seq(fence->rdev, fence->seq,
+				  fence->ring, intr, true);
+	if (r) {
+		return r;
 	}
-	timeout = rdev->fence_drv[fence->ring].last_timeout;
-retry:
-	/* save current sequence used to check for GPU lockup */
-	seq = rdev->fence_drv[fence->ring].last_seq;
-	trace_radeon_fence_wait_begin(rdev->ddev, seq);
-	if (intr) {
-		radeon_irq_kms_sw_irq_get(rdev, fence->ring);
-		r = wait_event_interruptible_timeout(rdev->fence_drv[fence->ring].queue,
-				radeon_fence_signaled(fence), timeout);
-		radeon_irq_kms_sw_irq_put(rdev, fence->ring);
-		if (unlikely(r < 0)) {
-			return r;
+	fence->seq = RADEON_FENCE_SIGNALED_SEQ;
+	return 0;
+}
+
+bool radeon_fence_any_seq_signaled(struct radeon_device *rdev, u64 *seq)
+{
+	unsigned i;
+
+	for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+		if (seq[i] && radeon_fence_seq_signaled(rdev, seq[i], i)) {
+			return true;
 		}
-	} else {
-		radeon_irq_kms_sw_irq_get(rdev, fence->ring);
-		r = wait_event_timeout(rdev->fence_drv[fence->ring].queue,
-			 radeon_fence_signaled(fence), timeout);
-		radeon_irq_kms_sw_irq_put(rdev, fence->ring);
 	}
-	trace_radeon_fence_wait_end(rdev->ddev, seq);
-	if (unlikely(!radeon_fence_signaled(fence))) {
-		/* we were interrupted for some reason and fence isn't
-		 * isn't signaled yet, resume wait
-		 */
-		if (r) {
-			timeout = r;
-			goto retry;
+	return false;
+}
+
+static int radeon_fence_wait_any_seq(struct radeon_device *rdev,
+				     u64 *target_seq, bool intr)
+{
+	unsigned long timeout, last_activity, tmp;
+	unsigned i, ring = RADEON_NUM_RINGS;
+	bool signaled;
+	int r;
+
+	for (i = 0, last_activity = 0; i < RADEON_NUM_RINGS; ++i) {
+		if (!target_seq[i]) {
+			continue;
+		}
+
+		/* use the most recent one as indicator */
+		if (time_after(rdev->fence_drv[i].last_activity, last_activity)) {
+			last_activity = rdev->fence_drv[i].last_activity;
 		}
-		/* don't protect read access to rdev->fence_drv[t].last_seq
-		 * if we experiencing a lockup the value doesn't change
+
+		/* For lockup detection just pick the lowest ring we are
+		 * actively waiting for
 		 */
-		if (seq == rdev->fence_drv[fence->ring].last_seq &&
-		    radeon_gpu_is_lockup(rdev, &rdev->ring[fence->ring])) {
-			/* good news we believe it's a lockup */
-			printk(KERN_WARNING "GPU lockup (waiting for 0x%08X last fence id 0x%08X)\n",
-			     fence->seq, seq);
-			/* FIXME: what should we do ? marking everyone
-			 * as signaled for now
+		if (i < ring) {
+			ring = i;
+		}
+	}
+
+	/* nothing to wait for ? */
+	if (ring == RADEON_NUM_RINGS) {
+		return 0;
+	}
+
+	while (!radeon_fence_any_seq_signaled(rdev, target_seq)) {
+		timeout = jiffies - RADEON_FENCE_JIFFIES_TIMEOUT;
+		if (time_after(last_activity, timeout)) {
+			/* the normal case, timeout is somewhere before last_activity */
+			timeout = last_activity - timeout;
+		} else {
+			/* either jiffies wrapped around, or no fence was signaled in the last 500ms
+			 * anyway we will just wait for the minimum amount and then check for a lockup
 			 */
-			rdev->gpu_lockup = true;
-			r = radeon_gpu_reset(rdev);
-			if (r)
-				return r;
-			radeon_fence_write(rdev, fence->seq, fence->ring);
-			rdev->gpu_lockup = false;
+			timeout = 1;
+		}
+
+		trace_radeon_fence_wait_begin(rdev->ddev, target_seq[ring]);
+		for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+			if (target_seq[i]) {
+				radeon_irq_kms_sw_irq_get(rdev, i);
+			}
+		}
+		if (intr) {
+			r = wait_event_interruptible_timeout(rdev->fence_queue,
+				(signaled = radeon_fence_any_seq_signaled(rdev, target_seq)),
+				timeout);
+		} else {
+			r = wait_event_timeout(rdev->fence_queue,
+				(signaled = radeon_fence_any_seq_signaled(rdev, target_seq)),
+				timeout);
+		}
+		for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+			if (target_seq[i]) {
+				radeon_irq_kms_sw_irq_put(rdev, i);
+			}
+		}
+		if (unlikely(r < 0)) {
+			return r;
+		}
+		trace_radeon_fence_wait_end(rdev->ddev, target_seq[ring]);
+
+		if (unlikely(!signaled)) {
+			/* we were interrupted for some reason and fence
+			 * isn't signaled yet, resume waiting */
+			if (r) {
+				continue;
+			}
+
+			mutex_lock(&rdev->ring_lock);
+			for (i = 0, tmp = 0; i < RADEON_NUM_RINGS; ++i) {
+				if (time_after(rdev->fence_drv[i].last_activity, tmp)) {
+					tmp = rdev->fence_drv[i].last_activity;
+				}
+			}
+			/* test if somebody else has already decided that this is a lockup */
+			if (last_activity != tmp) {
+				last_activity = tmp;
+				mutex_unlock(&rdev->ring_lock);
+				continue;
+			}
+
+			if (radeon_ring_is_lockup(rdev, ring, &rdev->ring[ring])) {
+				/* good news we believe it's a lockup */
+				dev_warn(rdev->dev, "GPU lockup (waiting for 0x%016llx)\n",
+					 target_seq[ring]);
+
+				/* change last activity so nobody else think there is a lockup */
+				for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+					rdev->fence_drv[i].last_activity = jiffies;
+				}
+
+				/* mark the ring as not ready any more */
+				rdev->ring[ring].ready = false;
+				mutex_unlock(&rdev->ring_lock);
+				return -EDEADLK;
+			}
+			mutex_unlock(&rdev->ring_lock);
 		}
-		timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
-		write_lock_irqsave(&rdev->fence_lock, irq_flags);
-		rdev->fence_drv[fence->ring].last_timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
-		rdev->fence_drv[fence->ring].last_jiffies = jiffies;
-		write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
-		goto retry;
 	}
 	return 0;
 }
 
-int radeon_fence_wait_next(struct radeon_device *rdev, int ring)
+int radeon_fence_wait_any(struct radeon_device *rdev,
+			  struct radeon_fence **fences,
+			  bool intr)
 {
-	unsigned long irq_flags;
-	struct radeon_fence *fence;
+	uint64_t seq[RADEON_NUM_RINGS];
+	unsigned i;
 	int r;
 
-	if (rdev->gpu_lockup) {
-		return 0;
+	for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+		seq[i] = 0;
+
+		if (!fences[i]) {
+			continue;
+		}
+
+		if (fences[i]->seq == RADEON_FENCE_SIGNALED_SEQ) {
+			/* something was allready signaled */
+			return 0;
+		}
+
+		if (fences[i]->seq < RADEON_FENCE_NOTEMITED_SEQ) {
+			seq[i] = fences[i]->seq;
+		}
 	}
-	write_lock_irqsave(&rdev->fence_lock, irq_flags);
-	if (list_empty(&rdev->fence_drv[ring].emitted)) {
-		write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
-		return 0;
+
+	r = radeon_fence_wait_any_seq(rdev, seq, intr);
+	if (r) {
+		return r;
 	}
-	fence = list_entry(rdev->fence_drv[ring].emitted.next,
-			   struct radeon_fence, list);
-	radeon_fence_ref(fence);
-	write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
-	r = radeon_fence_wait(fence, false);
-	radeon_fence_unref(&fence);
-	return r;
+	return 0;
 }
 
-int radeon_fence_wait_last(struct radeon_device *rdev, int ring)
+int radeon_fence_wait_next_locked(struct radeon_device *rdev, int ring)
 {
-	unsigned long irq_flags;
-	struct radeon_fence *fence;
-	int r;
-
-	if (rdev->gpu_lockup) {
-		return 0;
+	uint64_t seq;
+
+	/* We are not protected by ring lock when reading current seq but
+	 * it's ok as worst case is we return to early while we could have
+	 * wait.
+	 */
+	seq = atomic64_read(&rdev->fence_drv[ring].last_seq) + 1ULL;
+	if (seq >= rdev->fence_drv[ring].seq) {
+		/* nothing to wait for, last_seq is
+		   already the last emited fence */
+		return -ENOENT;
 	}
-	write_lock_irqsave(&rdev->fence_lock, irq_flags);
-	if (list_empty(&rdev->fence_drv[ring].emitted)) {
-		write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
-		return 0;
-	}
-	fence = list_entry(rdev->fence_drv[ring].emitted.prev,
-			   struct radeon_fence, list);
-	radeon_fence_ref(fence);
-	write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
-	r = radeon_fence_wait(fence, false);
-	radeon_fence_unref(&fence);
-	return r;
+	return radeon_fence_wait_seq(rdev, seq, ring, false, false);
+}
+
+int radeon_fence_wait_empty_locked(struct radeon_device *rdev, int ring)
+{
+	/* We are not protected by ring lock when reading current seq
+	 * but it's ok as wait empty is call from place where no more
+	 * activity can be scheduled so there won't be concurrent access
+	 * to seq value.
+	 */
+	return radeon_fence_wait_seq(rdev, rdev->fence_drv[ring].seq,
+				     ring, false, false);
 }
 
 struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence)
@@ -345,49 +500,27 @@ void radeon_fence_unref(struct radeon_fence **fence)
 	}
 }
 
-void radeon_fence_process(struct radeon_device *rdev, int ring)
-{
-	unsigned long irq_flags;
-	bool wake;
-
-	write_lock_irqsave(&rdev->fence_lock, irq_flags);
-	wake = radeon_fence_poll_locked(rdev, ring);
-	write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
-	if (wake) {
-		wake_up_all(&rdev->fence_drv[ring].queue);
-	}
-}
-
-int radeon_fence_count_emitted(struct radeon_device *rdev, int ring)
+unsigned radeon_fence_count_emitted(struct radeon_device *rdev, int ring)
 {
-	unsigned long irq_flags;
-	int not_processed = 0;
-
-	read_lock_irqsave(&rdev->fence_lock, irq_flags);
-	if (!rdev->fence_drv[ring].initialized) {
-		read_unlock_irqrestore(&rdev->fence_lock, irq_flags);
-		return 0;
+	uint64_t emitted;
+
+	/* We are not protected by ring lock when reading the last sequence
+	 * but it's ok to report slightly wrong fence count here.
+	 */
+	radeon_fence_process(rdev, ring);
+	emitted = rdev->fence_drv[ring].seq - atomic64_read(&rdev->fence_drv[ring].last_seq);
+	/* to avoid 32bits warp around */
+	if (emitted > 0x10000000) {
+		emitted = 0x10000000;
 	}
-
-	if (!list_empty(&rdev->fence_drv[ring].emitted)) {
-		struct list_head *ptr;
-		list_for_each(ptr, &rdev->fence_drv[ring].emitted) {
-			/* count up to 3, that's enought info */
-			if (++not_processed >= 3)
-				break;
-		}
-	}
-	read_unlock_irqrestore(&rdev->fence_lock, irq_flags);
-	return not_processed;
+	return (unsigned)emitted;
 }
 
 int radeon_fence_driver_start_ring(struct radeon_device *rdev, int ring)
 {
-	unsigned long irq_flags;
 	uint64_t index;
 	int r;
 
-	write_lock_irqsave(&rdev->fence_lock, irq_flags);
 	radeon_scratch_free(rdev, rdev->fence_drv[ring].scratch_reg);
 	if (rdev->wb.use_event) {
 		rdev->fence_drv[ring].scratch_reg = 0;
@@ -396,7 +529,6 @@ int radeon_fence_driver_start_ring(struct radeon_device *rdev, int ring)
 		r = radeon_scratch_get(rdev, &rdev->fence_drv[ring].scratch_reg);
 		if (r) {
 			dev_err(rdev->dev, "fence failed to get scratch register\n");
-			write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
 			return r;
 		}
 		index = RADEON_WB_SCRATCH_OFFSET +
@@ -405,11 +537,10 @@ int radeon_fence_driver_start_ring(struct radeon_device *rdev, int ring)
 	}
 	rdev->fence_drv[ring].cpu_addr = &rdev->wb.wb[index/4];
 	rdev->fence_drv[ring].gpu_addr = rdev->wb.gpu_addr + index;
-	radeon_fence_write(rdev, atomic_read(&rdev->fence_drv[ring].seq), ring);
+	radeon_fence_write(rdev, rdev->fence_drv[ring].seq, ring);
 	rdev->fence_drv[ring].initialized = true;
-	DRM_INFO("fence driver on ring %d use gpu addr 0x%08Lx and cpu addr 0x%p\n",
+	dev_info(rdev->dev, "fence driver on ring %d use gpu addr 0x%016llx and cpu addr 0x%p\n",
 		 ring, rdev->fence_drv[ring].gpu_addr, rdev->fence_drv[ring].cpu_addr);
-	write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
 	return 0;
 }
 
@@ -418,24 +549,20 @@ static void radeon_fence_driver_init_ring(struct radeon_device *rdev, int ring)
 	rdev->fence_drv[ring].scratch_reg = -1;
 	rdev->fence_drv[ring].cpu_addr = NULL;
 	rdev->fence_drv[ring].gpu_addr = 0;
-	atomic_set(&rdev->fence_drv[ring].seq, 0);
-	INIT_LIST_HEAD(&rdev->fence_drv[ring].created);
-	INIT_LIST_HEAD(&rdev->fence_drv[ring].emitted);
-	INIT_LIST_HEAD(&rdev->fence_drv[ring].signaled);
-	init_waitqueue_head(&rdev->fence_drv[ring].queue);
+	rdev->fence_drv[ring].seq = 0;
+	atomic64_set(&rdev->fence_drv[ring].last_seq, 0);
+	rdev->fence_drv[ring].last_activity = jiffies;
 	rdev->fence_drv[ring].initialized = false;
 }
 
 int radeon_fence_driver_init(struct radeon_device *rdev)
 {
-	unsigned long irq_flags;
 	int ring;
 
-	write_lock_irqsave(&rdev->fence_lock, irq_flags);
+	init_waitqueue_head(&rdev->fence_queue);
 	for (ring = 0; ring < RADEON_NUM_RINGS; ring++) {
 		radeon_fence_driver_init_ring(rdev, ring);
 	}
-	write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
 	if (radeon_debugfs_fence_init(rdev)) {
 		dev_err(rdev->dev, "fence debugfs file creation failed\n");
 	}
@@ -444,19 +571,18 @@ int radeon_fence_driver_init(struct radeon_device *rdev)
 
 void radeon_fence_driver_fini(struct radeon_device *rdev)
 {
-	unsigned long irq_flags;
 	int ring;
 
+	mutex_lock(&rdev->ring_lock);
 	for (ring = 0; ring < RADEON_NUM_RINGS; ring++) {
 		if (!rdev->fence_drv[ring].initialized)
 			continue;
-		radeon_fence_wait_last(rdev, ring);
-		wake_up_all(&rdev->fence_drv[ring].queue);
-		write_lock_irqsave(&rdev->fence_lock, irq_flags);
+		radeon_fence_wait_empty_locked(rdev, ring);
+		wake_up_all(&rdev->fence_queue);
 		radeon_scratch_free(rdev, rdev->fence_drv[ring].scratch_reg);
-		write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
 		rdev->fence_drv[ring].initialized = false;
 	}
+	mutex_unlock(&rdev->ring_lock);
 }
 
 
@@ -469,7 +595,6 @@ static int radeon_debugfs_fence_info(struct seq_file *m, void *data)
 	struct drm_info_node *node = (struct drm_info_node *)m->private;
 	struct drm_device *dev = node->minor->dev;
 	struct radeon_device *rdev = dev->dev_private;
-	struct radeon_fence *fence;
 	int i;
 
 	for (i = 0; i < RADEON_NUM_RINGS; ++i) {
@@ -477,14 +602,10 @@ static int radeon_debugfs_fence_info(struct seq_file *m, void *data)
 			continue;
 
 		seq_printf(m, "--- ring %d ---\n", i);
-		seq_printf(m, "Last signaled fence 0x%08X\n",
-			   radeon_fence_read(rdev, i));
-		if (!list_empty(&rdev->fence_drv[i].emitted)) {
-			fence = list_entry(rdev->fence_drv[i].emitted.prev,
-					   struct radeon_fence, list);
-			seq_printf(m, "Last emitted fence %p with 0x%08X\n",
-				   fence,  fence->seq);
-		}
+		seq_printf(m, "Last signaled fence 0x%016llx\n",
+			   (unsigned long long)atomic64_read(&rdev->fence_drv[i].last_seq));
+		seq_printf(m, "Last emitted  0x%016llx\n",
+			   rdev->fence_drv[i].seq);
 	}
 	return 0;
 }