drm/ttm/tests: Add test cases dependent on fence signaling

Add test cases that check how the state of dma fences in BO's
reservation object influence the ttm_bo_validation() flow. Do similar
tests for resource manager's move fence.
Signed-off-by: Karolina Stolarek <karolina.stolarek@intel.com>
Reviewed-by: Somalapuram, Amaranath <asomalap@amd.com>
Tested-by: Somalapuram, Amaranath <asomalap@amd.com>
Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/068791a27abd05bf2605f23cc31864a22c20b308.1718192625.git.karolina.stolarek@intel.com

drivers/gpu/drm/ttm/tests/ttm_bo_validate_test.c

@@ -2,6 +2,8 @@
 /*
  * Copyright © 2023 Intel Corporation
  */
+#include <linux/delay.h>
+#include <linux/kthread.h>
 
 #include <drm/ttm/ttm_resource.h>
 #include <drm/ttm/ttm_placement.h>
@@ -13,11 +15,14 @@
 #define BO_SIZE		SZ_4K
 #define MANAGER_SIZE	SZ_1M
 
+static struct spinlock fence_lock;
+
 struct ttm_bo_validate_test_case {
 	const char *description;
 	enum ttm_bo_type bo_type;
 	u32 mem_type;
 	bool with_ttm;
+	bool no_gpu_wait;
 };
 
 static struct ttm_placement *ttm_placement_kunit_init(struct kunit *test,
@@ -35,6 +40,43 @@ static struct ttm_placement *ttm_placement_kunit_init(struct kunit *test,
 	return placement;
 }
 
+static const char *fence_name(struct dma_fence *f)
+{
+	return "ttm-bo-validate-fence";
+}
+
+static const struct dma_fence_ops fence_ops = {
+	.get_driver_name = fence_name,
+	.get_timeline_name = fence_name,
+};
+
+static struct dma_fence *alloc_mock_fence(struct kunit *test)
+{
+	struct dma_fence *fence;
+
+	fence = kunit_kzalloc(test, sizeof(*fence), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, fence);
+
+	dma_fence_init(fence, &fence_ops, &fence_lock, 0, 0);
+
+	return fence;
+}
+
+static void dma_resv_kunit_active_fence_init(struct kunit *test,
+					     struct dma_resv *resv,
+					     enum dma_resv_usage usage)
+{
+	struct dma_fence *fence;
+
+	fence = alloc_mock_fence(test);
+	dma_fence_enable_sw_signaling(fence);
+
+	dma_resv_lock(resv, NULL);
+	dma_resv_reserve_fences(resv, 1);
+	dma_resv_add_fence(resv, fence, usage);
+	dma_resv_unlock(resv);
+}
+
 static void ttm_bo_validate_case_desc(const struct ttm_bo_validate_test_case *t,
 				      char *desc)
 {
@@ -459,6 +501,262 @@ static void ttm_bo_validate_multihop(struct kunit *test)
 	ttm_mock_manager_fini(priv->ttm_dev, tmp_mem);
 }
 
+static const struct ttm_bo_validate_test_case ttm_bo_no_placement_cases[] = {
+	{
+		.description = "Buffer object in system domain, no page vector",
+	},
+	{
+		.description = "Buffer object in system domain with an existing page vector",
+		.with_ttm = true,
+	},
+};
+
+KUNIT_ARRAY_PARAM(ttm_bo_no_placement, ttm_bo_no_placement_cases,
+		  ttm_bo_validate_case_desc);
+
+static void ttm_bo_validate_no_placement_signaled(struct kunit *test)
+{
+	const struct ttm_bo_validate_test_case *params = test->param_value;
+	enum ttm_bo_type bo_type = ttm_bo_type_device;
+	struct ttm_test_devices *priv = test->priv;
+	u32 size = ALIGN(BO_SIZE, PAGE_SIZE);
+	struct ttm_operation_ctx ctx = { };
+	u32 mem_type = TTM_PL_SYSTEM;
+	struct ttm_resource_manager *man;
+	struct ttm_placement *placement;
+	struct ttm_buffer_object *bo;
+	struct ttm_place *place;
+	struct ttm_tt *old_tt;
+	u32 flags;
+	int err;
+
+	place = ttm_place_kunit_init(test, mem_type, 0);
+	man = ttm_manager_type(priv->ttm_dev, mem_type);
+
+	bo = ttm_bo_kunit_init(test, test->priv, size, NULL);
+	bo->type = bo_type;
+
+	if (params->with_ttm) {
+		old_tt = priv->ttm_dev->funcs->ttm_tt_create(bo, 0);
+		ttm_pool_alloc(&priv->ttm_dev->pool, old_tt, &ctx);
+		bo->ttm = old_tt;
+	}
+
+	err = ttm_resource_alloc(bo, place, &bo->resource);
+	KUNIT_EXPECT_EQ(test, err, 0);
+	KUNIT_ASSERT_EQ(test, man->usage, size);
+
+	placement = kunit_kzalloc(test, sizeof(*placement), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, placement);
+
+	ttm_bo_reserve(bo, false, false, NULL);
+	err = ttm_bo_validate(bo, placement, &ctx);
+	ttm_bo_unreserve(bo);
+
+	KUNIT_EXPECT_EQ(test, err, 0);
+	KUNIT_ASSERT_EQ(test, man->usage, 0);
+	KUNIT_ASSERT_NOT_NULL(test, bo->ttm);
+	KUNIT_EXPECT_EQ(test, ctx.bytes_moved, 0);
+
+	if (params->with_ttm) {
+		flags = bo->ttm->page_flags;
+
+		KUNIT_ASSERT_PTR_EQ(test, bo->ttm, old_tt);
+		KUNIT_ASSERT_FALSE(test, flags & TTM_TT_FLAG_PRIV_POPULATED);
+		KUNIT_ASSERT_TRUE(test, flags & TTM_TT_FLAG_ZERO_ALLOC);
+	}
+
+	ttm_bo_put(bo);
+}
+
+static int threaded_dma_resv_signal(void *arg)
+{
+	struct ttm_buffer_object *bo = arg;
+	struct dma_resv *resv = bo->base.resv;
+	struct dma_resv_iter cursor;
+	struct dma_fence *fence;
+
+	dma_resv_iter_begin(&cursor, resv, DMA_RESV_USAGE_BOOKKEEP);
+	dma_resv_for_each_fence_unlocked(&cursor, fence) {
+		dma_fence_signal(fence);
+	}
+	dma_resv_iter_end(&cursor);
+
+	return 0;
+}
+
+static void ttm_bo_validate_no_placement_not_signaled(struct kunit *test)
+{
+	const struct ttm_bo_validate_test_case *params = test->param_value;
+	enum dma_resv_usage usage = DMA_RESV_USAGE_BOOKKEEP;
+	u32 size = ALIGN(BO_SIZE, PAGE_SIZE);
+	struct ttm_operation_ctx ctx = { };
+	u32 mem_type = TTM_PL_SYSTEM;
+	struct ttm_placement *placement;
+	struct ttm_buffer_object *bo;
+	struct task_struct *task;
+	struct ttm_place *place;
+	int err;
+
+	place = ttm_place_kunit_init(test, mem_type, 0);
+
+	bo = ttm_bo_kunit_init(test, test->priv, size, NULL);
+	bo->type = params->bo_type;
+
+	err = ttm_resource_alloc(bo, place, &bo->resource);
+	KUNIT_EXPECT_EQ(test, err, 0);
+
+	placement = kunit_kzalloc(test, sizeof(*placement), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, placement);
+
+	/* Create an active fence to simulate a non-idle resv object */
+	spin_lock_init(&fence_lock);
+	dma_resv_kunit_active_fence_init(test, bo->base.resv, usage);
+
+	task = kthread_create(threaded_dma_resv_signal, bo, "dma-resv-signal");
+	if (IS_ERR(task))
+		KUNIT_FAIL(test, "Couldn't create dma resv signal task\n");
+
+	wake_up_process(task);
+	ttm_bo_reserve(bo, false, false, NULL);
+	err = ttm_bo_validate(bo, placement, &ctx);
+	ttm_bo_unreserve(bo);
+
+	KUNIT_EXPECT_EQ(test, err, 0);
+	KUNIT_ASSERT_NOT_NULL(test, bo->ttm);
+	KUNIT_ASSERT_NULL(test, bo->resource);
+	KUNIT_ASSERT_NULL(test, bo->bulk_move);
+	KUNIT_EXPECT_EQ(test, ctx.bytes_moved, 0);
+
+	if (bo->type != ttm_bo_type_sg)
+		KUNIT_ASSERT_PTR_EQ(test, bo->base.resv, &bo->base._resv);
+
+	/* Make sure we have an idle object at this point */
+	dma_resv_wait_timeout(bo->base.resv, usage, false, MAX_SCHEDULE_TIMEOUT);
+
+	ttm_bo_put(bo);
+}
+
+static void ttm_bo_validate_move_fence_signaled(struct kunit *test)
+{
+	enum ttm_bo_type bo_type = ttm_bo_type_device;
+	struct ttm_test_devices *priv = test->priv;
+	u32 size = ALIGN(BO_SIZE, PAGE_SIZE);
+	struct ttm_operation_ctx ctx = { };
+	u32 mem_type = TTM_PL_SYSTEM;
+	struct ttm_resource_manager *man;
+	struct ttm_placement *placement;
+	struct ttm_buffer_object *bo;
+	struct ttm_place *place;
+	int err;
+
+	man = ttm_manager_type(priv->ttm_dev, mem_type);
+	man->move = dma_fence_get_stub();
+
+	bo = ttm_bo_kunit_init(test, test->priv, size, NULL);
+	bo->type = bo_type;
+
+	place = ttm_place_kunit_init(test, mem_type, 0);
+	placement = ttm_placement_kunit_init(test, place, 1);
+
+	ttm_bo_reserve(bo, false, false, NULL);
+	err = ttm_bo_validate(bo, placement, &ctx);
+	ttm_bo_unreserve(bo);
+
+	KUNIT_EXPECT_EQ(test, err, 0);
+	KUNIT_EXPECT_EQ(test, bo->resource->mem_type, mem_type);
+	KUNIT_EXPECT_EQ(test, ctx.bytes_moved, size);
+
+	ttm_bo_put(bo);
+	dma_fence_put(man->move);
+}
+
+static const struct ttm_bo_validate_test_case ttm_bo_validate_wait_cases[] = {
+	{
+		.description = "Waits for GPU",
+		.no_gpu_wait = false,
+	},
+	{
+		.description = "Tries to lock straight away",
+		.no_gpu_wait = true,
+	},
+};
+
+KUNIT_ARRAY_PARAM(ttm_bo_validate_wait, ttm_bo_validate_wait_cases,
+		  ttm_bo_validate_case_desc);
+
+static int threaded_fence_signal(void *arg)
+{
+	struct dma_fence *fence = arg;
+
+	msleep(20);
+
+	return dma_fence_signal(fence);
+}
+
+static void ttm_bo_validate_move_fence_not_signaled(struct kunit *test)
+{
+	const struct ttm_bo_validate_test_case *params = test->param_value;
+	struct ttm_operation_ctx ctx_init = { },
+				 ctx_val  = { .no_wait_gpu = params->no_gpu_wait };
+	u32 fst_mem = TTM_PL_VRAM, snd_mem = TTM_PL_VRAM + 1;
+	struct ttm_placement *placement_init, *placement_val;
+	enum ttm_bo_type bo_type = ttm_bo_type_device;
+	struct ttm_test_devices *priv = test->priv;
+	u32 size = ALIGN(BO_SIZE, PAGE_SIZE);
+	struct ttm_place *init_place, places[2];
+	struct ttm_resource_manager *man;
+	struct ttm_buffer_object *bo;
+	struct task_struct *task;
+	int err;
+
+	init_place = ttm_place_kunit_init(test, TTM_PL_SYSTEM, 0);
+	placement_init = ttm_placement_kunit_init(test, init_place, 1);
+
+	bo = kunit_kzalloc(test, sizeof(*bo), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, bo);
+
+	drm_gem_private_object_init(priv->drm, &bo->base, size);
+
+	err = ttm_bo_init_reserved(priv->ttm_dev, bo, bo_type, placement_init,
+				   PAGE_SIZE, &ctx_init, NULL, NULL,
+				   &dummy_ttm_bo_destroy);
+	KUNIT_EXPECT_EQ(test, err, 0);
+
+	ttm_mock_manager_init(priv->ttm_dev, fst_mem, MANAGER_SIZE);
+	ttm_mock_manager_init(priv->ttm_dev, snd_mem, MANAGER_SIZE);
+
+	places[0] = (struct ttm_place){ .mem_type = fst_mem, .flags = TTM_PL_FLAG_DESIRED };
+	places[1] = (struct ttm_place){ .mem_type = snd_mem, .flags = TTM_PL_FLAG_FALLBACK };
+	placement_val = ttm_placement_kunit_init(test, places, 2);
+
+	spin_lock_init(&fence_lock);
+	man = ttm_manager_type(priv->ttm_dev, fst_mem);
+	man->move = alloc_mock_fence(test);
+
+	task = kthread_create(threaded_fence_signal, man->move, "move-fence-signal");
+	if (IS_ERR(task))
+		KUNIT_FAIL(test, "Couldn't create move fence signal task\n");
+
+	wake_up_process(task);
+	err = ttm_bo_validate(bo, placement_val, &ctx_val);
+	dma_resv_unlock(bo->base.resv);
+
+	dma_fence_wait_timeout(man->move, false, MAX_SCHEDULE_TIMEOUT);
+
+	KUNIT_EXPECT_EQ(test, err, 0);
+	KUNIT_EXPECT_EQ(test, ctx_val.bytes_moved, size);
+
+	if (params->no_gpu_wait)
+		KUNIT_EXPECT_EQ(test, bo->resource->mem_type, snd_mem);
+	else
+		KUNIT_EXPECT_EQ(test, bo->resource->mem_type, fst_mem);
+
+	ttm_bo_put(bo);
+	ttm_mock_manager_fini(priv->ttm_dev, fst_mem);
+	ttm_mock_manager_fini(priv->ttm_dev, snd_mem);
+}
+
 static struct kunit_case ttm_bo_validate_test_cases[] = {
 	KUNIT_CASE_PARAM(ttm_bo_init_reserved_sys_man, ttm_bo_types_gen_params),
 	KUNIT_CASE_PARAM(ttm_bo_init_reserved_mock_man, ttm_bo_types_gen_params),
@@ -471,6 +769,13 @@ static struct kunit_case ttm_bo_validate_test_cases[] = {
 	KUNIT_CASE(ttm_bo_validate_pinned),
 	KUNIT_CASE(ttm_bo_validate_busy_placement),
 	KUNIT_CASE_PARAM(ttm_bo_validate_multihop, ttm_bo_types_gen_params),
+	KUNIT_CASE_PARAM(ttm_bo_validate_no_placement_signaled,
+			 ttm_bo_no_placement_gen_params),
+	KUNIT_CASE_PARAM(ttm_bo_validate_no_placement_not_signaled,
+			 ttm_bo_types_gen_params),
+	KUNIT_CASE(ttm_bo_validate_move_fence_signaled),
+	KUNIT_CASE_PARAM(ttm_bo_validate_move_fence_not_signaled,
+			 ttm_bo_validate_wait_gen_params),
 	{}
 };