1 files changed, 28 insertions, 26 deletions

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index dcaa85a91090..e5a55801f753 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -51,7 +51,6 @@ struct execute_cb {
 static struct i915_global_request {
 	struct i915_global base;
 	struct kmem_cache *slab_requests;
-	struct kmem_cache *slab_dependencies;
 	struct kmem_cache *slab_execute_cbs;
 } global;
 
@@ -203,6 +202,19 @@ static void free_capture_list(struct i915_request *request)
 	}
 }
 
+static void __i915_request_fill(struct i915_request *rq, u8 val)
+{
+	void *vaddr = rq->ring->vaddr;
+	u32 head;
+
+	head = rq->infix;
+	if (rq->postfix < head) {
+		memset(vaddr + head, val, rq->ring->size - head);
+		head = 0;
+	}
+	memset(vaddr + head, val, rq->postfix - head);
+}
+
 static void remove_from_engine(struct i915_request *rq)
 {
 	struct intel_engine_cs *engine, *locked;
@@ -247,6 +259,9 @@ bool i915_request_retire(struct i915_request *rq)
 	 */
 	GEM_BUG_ON(!list_is_first(&rq->link,
 				  &i915_request_timeline(rq)->requests));
+	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+		/* Poison before we release our space in the ring */
+		__i915_request_fill(rq, POISON_FREE);
 	rq->ring->head = rq->postfix;
 
 	/*
@@ -903,6 +918,12 @@ emit_semaphore_wait(struct i915_request *to,
 		    struct i915_request *from,
 		    gfp_t gfp)
 {
+	if (!intel_context_use_semaphores(to->context))
+		goto await_fence;
+
+	if (!rcu_access_pointer(from->hwsp_cacheline))
+		goto await_fence;
+
 	/* Just emit the first semaphore we see as request space is limited. */
 	if (already_busywaiting(to) & from->engine->mask)
 		goto await_fence;
@@ -948,12 +969,8 @@ i915_request_await_request(struct i915_request *to, struct i915_request *from)
 		ret = i915_sw_fence_await_sw_fence_gfp(&to->submit,
 						       &from->submit,
 						       I915_FENCE_GFP);
-	else if (intel_context_use_semaphores(to->context))
-		ret = emit_semaphore_wait(to, from, I915_FENCE_GFP);
 	else
-		ret = i915_sw_fence_await_dma_fence(&to->submit,
-						    &from->fence, 0,
-						    I915_FENCE_GFP);
+		ret = emit_semaphore_wait(to, from, I915_FENCE_GFP);
 	if (ret < 0)
 		return ret;
 
@@ -1052,6 +1069,8 @@ __i915_request_await_execution(struct i915_request *to,
 {
 	int err;
 
+	GEM_BUG_ON(intel_context_is_barrier(from->context));
+
 	/* Submit both requests at the same time */
 	err = __await_execution(to, from, hook, I915_FENCE_GFP);
 	if (err)
@@ -1192,9 +1211,6 @@ i915_request_await_object(struct i915_request *to,
 
 void i915_request_skip(struct i915_request *rq, int error)
 {
-	void *vaddr = rq->ring->vaddr;
-	u32 head;
-
 	GEM_BUG_ON(!IS_ERR_VALUE((long)error));
 	dma_fence_set_error(&rq->fence, error);
 
@@ -1206,12 +1222,7 @@ void i915_request_skip(struct i915_request *rq, int error)
 	 * context, clear out all the user operations leaving the
 	 * breadcrumb at the end (so we get the fence notifications).
 	 */
-	head = rq->infix;
-	if (rq->postfix < head) {
-		memset(vaddr + head, 0, rq->ring->size - head);
-		head = 0;
-	}
-	memset(vaddr + head, 0, rq->postfix - head);
+	__i915_request_fill(rq, 0);
 	rq->infix = rq->postfix;
 }
 
@@ -1586,6 +1597,8 @@ long i915_request_wait(struct i915_request *rq,
 			break;
 		}
 
+		intel_engine_flush_submission(rq->engine);
+
 		if (signal_pending_state(state, current)) {
 			timeout = -ERESTARTSYS;
 			break;
@@ -1596,7 +1609,6 @@ long i915_request_wait(struct i915_request *rq,
 			break;
 		}
 
-		intel_engine_flush_submission(rq->engine);
 		timeout = io_schedule_timeout(timeout);
 	}
 	__set_current_state(TASK_RUNNING);
@@ -1616,14 +1628,12 @@ out:
 
 static void i915_global_request_shrink(void)
 {
-	kmem_cache_shrink(global.slab_dependencies);
 	kmem_cache_shrink(global.slab_execute_cbs);
 	kmem_cache_shrink(global.slab_requests);
 }
 
 static void i915_global_request_exit(void)
 {
-	kmem_cache_destroy(global.slab_dependencies);
 	kmem_cache_destroy(global.slab_execute_cbs);
 	kmem_cache_destroy(global.slab_requests);
 }
@@ -1653,17 +1663,9 @@ int __init i915_global_request_init(void)
 	if (!global.slab_execute_cbs)
 		goto err_requests;
 
-	global.slab_dependencies = KMEM_CACHE(i915_dependency,
-					      SLAB_HWCACHE_ALIGN |
-					      SLAB_RECLAIM_ACCOUNT);
-	if (!global.slab_dependencies)
-		goto err_execute_cbs;
-
 	i915_global_register(&global.base);
 	return 0;
 
-err_execute_cbs:
-	kmem_cache_destroy(global.slab_execute_cbs);
 err_requests:
 	kmem_cache_destroy(global.slab_requests);
 	return -ENOMEM;