Hardware can't handle seqno wrapping so all previous requests need to
be retired before seqno can wrap. As this can fail, make seqno
allocation explicit by introducing i915_gem_alloc_seqno()
Signed-off-by: Mika Kuoppala <mika.kuoppala at intel.com>
---
drivers/gpu/drm/i915/i915_drv.h | 1 +
drivers/gpu/drm/i915/i915_gem.c | 51 +++++++++++++++++++++++++++++++++++++++
2 files changed, 52 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index f511fa2..598f3b8 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1387,6 +1387,7 @@ i915_seqno_passed(uint32_t seq1, uint32_t seq2)
return (int32_t)(seq1 - seq2) >= 0;
}
+int i915_gem_alloc_seqno(struct intel_ring_buffer *ring, u32 *seqno);
u32 i915_gem_next_request_seqno(struct intel_ring_buffer *ring);
int __must_check i915_gem_object_get_fence(struct drm_i915_gem_object *obj);
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 7e17382..a637d5d 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1933,6 +1933,34 @@ i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj)
WARN_ON(i915_verify_lists(dev));
}
+static int
+i915_gem_handle_seqno_wrap(struct drm_device *dev)
+{
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ struct intel_ring_buffer *ring;
+ int ret;
+ int i;
+
+ /* The GPU can not handle its semaphore value wrapping,
+ + * so every billion or so execbuffers, we need to stall
+ * the GPU in order to reset the counters.
+ */
+
+ ret = i915_gpu_idle(dev);
+ if (ret)
+ return ret;
+
+ i915_gem_retire_requests(dev);
+
+ for_each_ring(ring, dev_priv, i) {
+ int j;
+ for (j = 0; j < ARRAY_SIZE(ring->sync_seqno); j++)
+ BUG_ON(ring->sync_seqno[j]);
+ }
+
+ return 0;
+}
+
static u32
i915_gem_get_seqno(struct drm_device *dev)
{
@@ -1956,6 +1984,29 @@ i915_gem_next_request_seqno(struct intel_ring_buffer *ring)
}
int
+i915_gem_alloc_seqno(struct intel_ring_buffer *ring, u32 *seqno)
+{
+ drm_i915_private_t *dev_priv = ring->dev->dev_private;
+ int ret;
+
+ /* reserve 0 for non-seqno */
+ if (unlikely(dev_priv->next_seqno == ~0)) {
+ ret = i915_gem_handle_seqno_wrap(ring->dev);
+ if (ret)
+ return ret;
+
+ dev_priv->next_seqno = 1;
+ }
+
+ dev_priv->next_seqno++;
+
+ if (seqno)
+ *seqno = i915_gem_next_request_seqno(ring);
+
+ return 0;
+}
+
+int
i915_add_request(struct intel_ring_buffer *ring,
struct drm_file *file,
u32 *out_seqno)
--
1.7.9.5
