drm/ttm/tests: Add tests for ttm_pool

Add KUnit tests that exercise page allocation using page pools
and freeing pages, either by returning them to the pool or
freeing them. Add a basic test for ttm_pool cleanup. Introduce
helpers to create a dummy ttm_buffer_object.
Signed-off-by: Karolina Stolarek <karolina.stolarek@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/427ea373357d0b6cb376c9d7ebc33c930bf1d28a.1691487006.git.karolina.stolarek@intel.comSigned-off-by: Christian König <christian.koenig@amd.com>

drivers/gpu/drm/ttm/tests/Makefile

@@ -2,4 +2,5 @@
 
 obj-$(CONFIG_DRM_TTM_KUNIT_TEST) += \
         ttm_device_test.o \
+        ttm_pool_test.o \
         ttm_kunit_helpers.o

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

@@ -25,6 +25,23 @@ int ttm_device_kunit_init(struct ttm_test_devices *priv,
 }
 EXPORT_SYMBOL_GPL(ttm_device_kunit_init);
 
+struct ttm_buffer_object *ttm_bo_kunit_init(struct kunit *test,
+					    struct ttm_test_devices *devs,
+					    size_t size)
+{
+	struct drm_gem_object gem_obj = { .size = size };
+	struct ttm_buffer_object *bo;
+
+	bo = kunit_kzalloc(test, sizeof(*bo), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, bo);
+
+	bo->base = gem_obj;
+	bo->bdev = devs->ttm_dev;
+
+	return bo;
+}
+EXPORT_SYMBOL_GPL(ttm_bo_kunit_init);
+
 struct ttm_test_devices *ttm_test_devices_basic(struct kunit *test)
 {
 	struct ttm_test_devices *devs;

drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h

@@ -7,6 +7,7 @@
 
 #include <drm/drm_drv.h>
 #include <drm/ttm/ttm_device.h>
+#include <drm/ttm/ttm_bo.h>
 
 #include <drm/drm_kunit_helpers.h>
 #include <kunit/test.h>
@@ -24,6 +25,9 @@ int ttm_device_kunit_init(struct ttm_test_devices *priv,
 			  struct ttm_device *ttm,
 			  bool use_dma_alloc,
 			  bool use_dma32);
+struct ttm_buffer_object *ttm_bo_kunit_init(struct kunit *test,
+					    struct ttm_test_devices *devs,
+					    size_t size);
 
 struct ttm_test_devices *ttm_test_devices_basic(struct kunit *test);
 struct ttm_test_devices *ttm_test_devices_all(struct kunit *test);

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

+// SPDX-License-Identifier: GPL-2.0 AND MIT
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+#include <linux/mm.h>
+
+#include <drm/ttm/ttm_tt.h>
+#include <drm/ttm/ttm_pool.h>
+
+#include "ttm_kunit_helpers.h"
+
+struct ttm_pool_test_case {
+	const char *description;
+	unsigned int order;
+	bool use_dma_alloc;
+};
+
+struct ttm_pool_test_priv {
+	struct ttm_test_devices *devs;
+
+	/* Used to create mock ttm_tts */
+	struct ttm_buffer_object *mock_bo;
+};
+
+static struct ttm_operation_ctx simple_ctx = {
+	.interruptible = true,
+	.no_wait_gpu = false,
+};
+
+static int ttm_pool_test_init(struct kunit *test)
+{
+	struct ttm_pool_test_priv *priv;
+
+	priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, priv);
+
+	priv->devs = ttm_test_devices_basic(test);
+	test->priv = priv;
+
+	return 0;
+}
+
+static void ttm_pool_test_fini(struct kunit *test)
+{
+	struct ttm_pool_test_priv *priv = test->priv;
+
+	ttm_test_devices_put(test, priv->devs);
+}
+
+static struct ttm_tt *ttm_tt_kunit_init(struct kunit *test,
+					uint32_t page_flags,
+					enum ttm_caching caching,
+					size_t size)
+{
+	struct ttm_pool_test_priv *priv = test->priv;
+	struct ttm_buffer_object *bo;
+	struct ttm_tt *tt;
+	int err;
+
+	bo = ttm_bo_kunit_init(test, priv->devs, size);
+	KUNIT_ASSERT_NOT_NULL(test, bo);
+	priv->mock_bo = bo;
+
+	tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	err = ttm_tt_init(tt, priv->mock_bo, page_flags, caching, 0);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	return tt;
+}
+
+static struct ttm_pool *ttm_pool_pre_populated(struct kunit *test,
+					       size_t size,
+					       enum ttm_caching caching)
+{
+	struct ttm_pool_test_priv *priv = test->priv;
+	struct ttm_test_devices *devs = priv->devs;
+	struct ttm_pool *pool;
+	struct ttm_tt *tt;
+	unsigned long order = __fls(size / PAGE_SIZE);
+	int err;
+
+	tt = ttm_tt_kunit_init(test, order, caching, size);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	pool = kunit_kzalloc(test, sizeof(*pool), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, pool);
+
+	ttm_pool_init(pool, devs->dev, NUMA_NO_NODE, true, false);
+
+	err = ttm_pool_alloc(pool, tt, &simple_ctx);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	ttm_pool_free(pool, tt);
+	ttm_tt_fini(tt);
+
+	return pool;
+}
+
+static const struct ttm_pool_test_case ttm_pool_basic_cases[] = {
+	{
+		.description = "One page",
+		.order = 0,
+	},
+	{
+		.description = "More than one page",
+		.order = 2,
+	},
+	{
+		.description = "Above the allocation limit",
+		.order = MAX_ORDER + 1,
+	},
+	{
+		.description = "One page, with coherent DMA mappings enabled",
+		.order = 0,
+		.use_dma_alloc = true,
+	},
+	{
+		.description = "Above the allocation limit, with coherent DMA mappings enabled",
+		.order = MAX_ORDER + 1,
+		.use_dma_alloc = true,
+	},
+};
+
+static void ttm_pool_alloc_case_desc(const struct ttm_pool_test_case *t,
+				     char *desc)
+{
+	strscpy(desc, t->description, KUNIT_PARAM_DESC_SIZE);
+}
+
+KUNIT_ARRAY_PARAM(ttm_pool_alloc_basic, ttm_pool_basic_cases,
+		  ttm_pool_alloc_case_desc);
+
+static void ttm_pool_alloc_basic(struct kunit *test)
+{
+	struct ttm_pool_test_priv *priv = test->priv;
+	struct ttm_test_devices *devs = priv->devs;
+	const struct ttm_pool_test_case *params = test->param_value;
+	struct ttm_tt *tt;
+	struct ttm_pool *pool;
+	struct page *fst_page, *last_page;
+	enum ttm_caching caching = ttm_uncached;
+	unsigned int expected_num_pages = 1 << params->order;
+	size_t size = expected_num_pages * PAGE_SIZE;
+	int err;
+
+	tt = ttm_tt_kunit_init(test, 0, caching, size);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	pool = kunit_kzalloc(test, sizeof(*pool), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, pool);
+
+	ttm_pool_init(pool, devs->dev, NUMA_NO_NODE, params->use_dma_alloc,
+		      false);
+
+	KUNIT_ASSERT_PTR_EQ(test, pool->dev, devs->dev);
+	KUNIT_ASSERT_EQ(test, pool->nid, NUMA_NO_NODE);
+	KUNIT_ASSERT_EQ(test, pool->use_dma_alloc, params->use_dma_alloc);
+
+	err = ttm_pool_alloc(pool, tt, &simple_ctx);
+	KUNIT_ASSERT_EQ(test, err, 0);
+	KUNIT_ASSERT_EQ(test, tt->num_pages, expected_num_pages);
+
+	fst_page = tt->pages[0];
+	last_page = tt->pages[tt->num_pages - 1];
+
+	if (params->order <= MAX_ORDER) {
+		if (params->use_dma_alloc) {
+			KUNIT_ASSERT_NOT_NULL(test, (void *)fst_page->private);
+			KUNIT_ASSERT_NOT_NULL(test, (void *)last_page->private);
+		} else {
+			KUNIT_ASSERT_EQ(test, fst_page->private, params->order);
+		}
+	} else {
+		if (params->use_dma_alloc) {
+			KUNIT_ASSERT_NOT_NULL(test, (void *)fst_page->private);
+			KUNIT_ASSERT_NULL(test, (void *)last_page->private);
+		} else {
+			/*
+			 * We expect to alloc one big block, followed by
+			 * order 0 blocks
+			 */
+			KUNIT_ASSERT_EQ(test, fst_page->private,
+					min_t(unsigned int, MAX_ORDER,
+					      params->order));
+			KUNIT_ASSERT_EQ(test, last_page->private, 0);
+		}
+	}
+
+	ttm_pool_free(pool, tt);
+	ttm_tt_fini(tt);
+	ttm_pool_fini(pool);
+}
+
+static void ttm_pool_alloc_basic_dma_addr(struct kunit *test)
+{
+	struct ttm_pool_test_priv *priv = test->priv;
+	struct ttm_test_devices *devs = priv->devs;
+	const struct ttm_pool_test_case *params = test->param_value;
+	struct ttm_tt *tt;
+	struct ttm_pool *pool;
+	struct ttm_buffer_object *bo;
+	dma_addr_t dma1, dma2;
+	enum ttm_caching caching = ttm_uncached;
+	unsigned int expected_num_pages = 1 << params->order;
+	size_t size = expected_num_pages * PAGE_SIZE;
+	int err;
+
+	tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	bo = ttm_bo_kunit_init(test, devs, size);
+	KUNIT_ASSERT_NOT_NULL(test, bo);
+
+	err = ttm_sg_tt_init(tt, bo, 0, caching);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	pool = kunit_kzalloc(test, sizeof(*pool), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, pool);
+
+	ttm_pool_init(pool, devs->dev, NUMA_NO_NODE, true, false);
+
+	err = ttm_pool_alloc(pool, tt, &simple_ctx);
+	KUNIT_ASSERT_EQ(test, err, 0);
+	KUNIT_ASSERT_EQ(test, tt->num_pages, expected_num_pages);
+
+	dma1 = tt->dma_address[0];
+	dma2 = tt->dma_address[tt->num_pages - 1];
+
+	KUNIT_ASSERT_NOT_NULL(test, (void *)dma1);
+	KUNIT_ASSERT_NOT_NULL(test, (void *)dma2);
+
+	ttm_pool_free(pool, tt);
+	ttm_tt_fini(tt);
+	ttm_pool_fini(pool);
+}
+
+static void ttm_pool_alloc_order_caching_match(struct kunit *test)
+{
+	struct ttm_tt *tt;
+	struct ttm_pool *pool;
+	struct ttm_pool_type *pt;
+	enum ttm_caching caching = ttm_uncached;
+	unsigned int order = 0;
+	size_t size = PAGE_SIZE;
+	int err;
+
+	pool = ttm_pool_pre_populated(test, size, caching);
+
+	pt = &pool->caching[caching].orders[order];
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt->pages));
+
+	tt = ttm_tt_kunit_init(test, 0, caching, size);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	err = ttm_pool_alloc(pool, tt, &simple_ctx);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	KUNIT_ASSERT_TRUE(test, list_empty(&pt->pages));
+
+	ttm_pool_free(pool, tt);
+	ttm_tt_fini(tt);
+	ttm_pool_fini(pool);
+}
+
+static void ttm_pool_alloc_caching_mismatch(struct kunit *test)
+{
+	struct ttm_tt *tt;
+	struct ttm_pool *pool;
+	struct ttm_pool_type *pt_pool, *pt_tt;
+	enum ttm_caching tt_caching = ttm_uncached;
+	enum ttm_caching pool_caching = ttm_cached;
+	size_t size = PAGE_SIZE;
+	unsigned int order = 0;
+	int err;
+
+	pool = ttm_pool_pre_populated(test, size, pool_caching);
+
+	pt_pool = &pool->caching[pool_caching].orders[order];
+	pt_tt = &pool->caching[tt_caching].orders[order];
+
+	tt = ttm_tt_kunit_init(test, 0, tt_caching, size);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt_pool->pages));
+	KUNIT_ASSERT_TRUE(test, list_empty(&pt_tt->pages));
+
+	err = ttm_pool_alloc(pool, tt, &simple_ctx);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	ttm_pool_free(pool, tt);
+	ttm_tt_fini(tt);
+
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt_pool->pages));
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt_tt->pages));
+
+	ttm_pool_fini(pool);
+}
+
+static void ttm_pool_alloc_order_mismatch(struct kunit *test)
+{
+	struct ttm_tt *tt;
+	struct ttm_pool *pool;
+	struct ttm_pool_type *pt_pool, *pt_tt;
+	enum ttm_caching caching = ttm_uncached;
+	unsigned int order = 2;
+	size_t fst_size = (1 << order) * PAGE_SIZE;
+	size_t snd_size = PAGE_SIZE;
+	int err;
+
+	pool = ttm_pool_pre_populated(test, fst_size, caching);
+
+	pt_pool = &pool->caching[caching].orders[order];
+	pt_tt = &pool->caching[caching].orders[0];
+
+	tt = ttm_tt_kunit_init(test, 0, caching, snd_size);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt_pool->pages));
+	KUNIT_ASSERT_TRUE(test, list_empty(&pt_tt->pages));
+
+	err = ttm_pool_alloc(pool, tt, &simple_ctx);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	ttm_pool_free(pool, tt);
+	ttm_tt_fini(tt);
+
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt_pool->pages));
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt_tt->pages));
+
+	ttm_pool_fini(pool);
+}
+
+static void ttm_pool_free_dma_alloc(struct kunit *test)
+{
+	struct ttm_pool_test_priv *priv = test->priv;
+	struct ttm_test_devices *devs = priv->devs;
+	struct ttm_tt *tt;
+	struct ttm_pool *pool;
+	struct ttm_pool_type *pt;
+	enum ttm_caching caching = ttm_uncached;
+	unsigned int order = 2;
+	size_t size = (1 << order) * PAGE_SIZE;
+
+	tt = ttm_tt_kunit_init(test, 0, caching, size);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	pool = kunit_kzalloc(test, sizeof(*pool), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, pool);
+
+	ttm_pool_init(pool, devs->dev, NUMA_NO_NODE, true, false);
+	ttm_pool_alloc(pool, tt, &simple_ctx);
+
+	pt = &pool->caching[caching].orders[order];
+	KUNIT_ASSERT_TRUE(test, list_empty(&pt->pages));
+
+	ttm_pool_free(pool, tt);
+	ttm_tt_fini(tt);
+
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt->pages));
+
+	ttm_pool_fini(pool);
+}
+
+static void ttm_pool_free_no_dma_alloc(struct kunit *test)
+{
+	struct ttm_pool_test_priv *priv = test->priv;
+	struct ttm_test_devices *devs = priv->devs;
+	struct ttm_tt *tt;
+	struct ttm_pool *pool;
+	struct ttm_pool_type *pt;
+	enum ttm_caching caching = ttm_uncached;
+	unsigned int order = 2;
+	size_t size = (1 << order) * PAGE_SIZE;
+
+	tt = ttm_tt_kunit_init(test, 0, caching, size);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	pool = kunit_kzalloc(test, sizeof(*pool), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, pool);
+
+	ttm_pool_init(pool, devs->dev, NUMA_NO_NODE, false, false);
+	ttm_pool_alloc(pool, tt, &simple_ctx);
+
+	pt = &pool->caching[caching].orders[order];
+	KUNIT_ASSERT_TRUE(test, list_is_singular(&pt->pages));
+
+	ttm_pool_free(pool, tt);
+	ttm_tt_fini(tt);
+
+	KUNIT_ASSERT_TRUE(test, list_is_singular(&pt->pages));
+
+	ttm_pool_fini(pool);
+}
+
+static void ttm_pool_fini_basic(struct kunit *test)
+{
+	struct ttm_pool *pool;
+	struct ttm_pool_type *pt;
+	enum ttm_caching caching = ttm_uncached;
+	unsigned int order = 0;
+	size_t size = PAGE_SIZE;
+
+	pool = ttm_pool_pre_populated(test, size, caching);
+	pt = &pool->caching[caching].orders[order];
+
+	KUNIT_ASSERT_FALSE(test, list_empty(&pt->pages));
+
+	ttm_pool_fini(pool);
+
+	KUNIT_ASSERT_TRUE(test, list_empty(&pt->pages));
+}
+
+static struct kunit_case ttm_pool_test_cases[] = {
+	KUNIT_CASE_PARAM(ttm_pool_alloc_basic, ttm_pool_alloc_basic_gen_params),
+	KUNIT_CASE_PARAM(ttm_pool_alloc_basic_dma_addr,
+			 ttm_pool_alloc_basic_gen_params),
+	KUNIT_CASE(ttm_pool_alloc_order_caching_match),
+	KUNIT_CASE(ttm_pool_alloc_caching_mismatch),
+	KUNIT_CASE(ttm_pool_alloc_order_mismatch),
+	KUNIT_CASE(ttm_pool_free_dma_alloc),
+	KUNIT_CASE(ttm_pool_free_no_dma_alloc),
+	KUNIT_CASE(ttm_pool_fini_basic),
+	{}
+};
+
+static struct kunit_suite ttm_pool_test_suite = {
+	.name = "ttm_pool",
+	.init = ttm_pool_test_init,
+	.exit = ttm_pool_test_fini,
+	.test_cases = ttm_pool_test_cases,
+};
+
+kunit_test_suites(&ttm_pool_test_suite);
+
+MODULE_LICENSE("GPL");