[PATCH 26/29] drm/i915: Extend the priority boosting for the display with a deadline

[Chris Wilson]

For a modeset/pageflip, there is a very precise deadline by which the
frame must be completed in order to hit the vblank and be shown. While
we don't pass along that exact information, we can at least inform the
scheduler that this request-chain needs to be completed asap.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/display/intel_display.c |  7 +++++--
 drivers/gpu/drm/i915/gem/i915_gem_object.h   |  5 +++--
 drivers/gpu/drm/i915/gem/i915_gem_wait.c     | 21 ++++++++++++--------
 3 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 3ac5632478dc..cea47c94ad32 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -13581,7 +13581,8 @@ intel_prepare_plane_fb(struct drm_plane *_plane,
 
 	if (new_plane_state->uapi.fence) { /* explicit fencing */
 		i915_gem_fence_wait_priority(new_plane_state->uapi.fence,
-					     I915_PRIORITY_DISPLAY);
+					     I915_PRIORITY_DISPLAY,
+					     ktime_get() /* next vblank? */);
 		ret = i915_sw_fence_await_dma_fence(&state->commit_ready,
 						    new_plane_state->uapi.fence,
 						    i915_fence_timeout(dev_priv),
@@ -13603,7 +13604,9 @@ intel_prepare_plane_fb(struct drm_plane *_plane,
 	if (ret)
 		return ret;
 
-	i915_gem_object_wait_priority(obj, 0, I915_PRIORITY_DISPLAY);
+	i915_gem_object_wait_priority(obj, 0,
+				      I915_PRIORITY_DISPLAY,
+				      ktime_get() /* next vblank? */);
 	i915_gem_object_flush_frontbuffer(obj, ORIGIN_DIRTYFB);
 
 	if (!new_plane_state->uapi.fence) { /* implicit fencing */
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index 09ccdd9096db..ab091c675eef 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -517,14 +517,15 @@ static inline void __start_cpu_write(struct drm_i915_gem_object *obj)
 		obj->cache_dirty = true;
 }
 
-void i915_gem_fence_wait_priority(struct dma_fence *fence, int prio);
+void i915_gem_fence_wait_priority(struct dma_fence *fence,
+				  int prio, ktime_t deadline);
 
 int i915_gem_object_wait(struct drm_i915_gem_object *obj,
 			 unsigned int flags,
 			 long timeout);
 int i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
 				  unsigned int flags,
-				  int prio);
+				  int prio, ktime_t deadline);
 
 void __i915_gem_object_flush_frontbuffer(struct drm_i915_gem_object *obj,
 					 enum fb_op_origin origin);
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_wait.c b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
index 4d1897c347b9..162f9737965f 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_wait.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
@@ -92,11 +92,14 @@ i915_gem_object_wait_reservation(struct dma_resv *resv,
 	return timeout;
 }
 
-static void fence_set_priority(struct dma_fence *fence, int prio)
+static void
+fence_set_priority(struct dma_fence *fence, int prio, ktime_t deadline)
 {
 	if (dma_fence_is_signaled(fence) || !dma_fence_is_i915(fence))
 		return;
 
+	i915_request_set_deadline(to_request(fence),
+				  i915_sched_to_ticks(deadline));
 	i915_request_set_priority(to_request(fence), prio);
 }
 
@@ -105,7 +108,8 @@ static inline bool __dma_fence_is_chain(const struct dma_fence *fence)
 	return fence->ops == &dma_fence_chain_ops;
 }
 
-void i915_gem_fence_wait_priority(struct dma_fence *fence, int prio)
+void i915_gem_fence_wait_priority(struct dma_fence *fence,
+				  int prio, ktime_t deadline)
 {
 	if (dma_fence_is_signaled(fence))
 		return;
@@ -118,19 +122,19 @@ void i915_gem_fence_wait_priority(struct dma_fence *fence, int prio)
 		int i;
 
 		for (i = 0; i < array->num_fences; i++)
-			fence_set_priority(array->fences[i], prio);
+			fence_set_priority(array->fences[i], prio, deadline);
 	} else if (__dma_fence_is_chain(fence)) {
 		struct dma_fence *iter;
 
 		/* The chain is ordered; if we boost the last, we boost all */
 		dma_fence_chain_for_each(iter, fence) {
 			fence_set_priority(to_dma_fence_chain(iter)->fence,
-					   prio);
+					   prio, deadline);
 			break;
 		}
 		dma_fence_put(iter);
 	} else {
-		fence_set_priority(fence, prio);
+		fence_set_priority(fence, prio, deadline);
 	}
 
 	local_bh_enable(); /* kick the tasklets if queues were reprioritised */
@@ -139,7 +143,8 @@ void i915_gem_fence_wait_priority(struct dma_fence *fence, int prio)
 int
 i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
 			      unsigned int flags,
-			      int prio)
+			      int prio,
+			      ktime_t deadline)
 {
 	struct dma_fence *excl;
 
@@ -154,7 +159,7 @@ i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
 			return ret;
 
 		for (i = 0; i < count; i++) {
-			i915_gem_fence_wait_priority(shared[i], prio);
+			i915_gem_fence_wait_priority(shared[i], prio, deadline);
 			dma_fence_put(shared[i]);
 		}
 
@@ -164,7 +169,7 @@ i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
 	}
 
 	if (excl) {
-		i915_gem_fence_wait_priority(excl, prio);
+		i915_gem_fence_wait_priority(excl, prio, deadline);
 		dma_fence_put(excl);
 	}
 	return 0;
-- 
2.20.1