From: "Christian König" <christian.koenig@amd.com>
To: Karolina Stolarek <karolina.stolarek@intel.com>,
dri-devel@lists.freedesktop.org
Cc: "Thomas Hellström" <thomas.hellstrom@linux.intel.com>,
"Mauro Carvalho Chehab" <mauro.chehab@linux.intel.com>,
"Shuah Khan" <shuah@kernel.org>,
"Andi Shyti" <andi.shyti@linux.intel.com>,
"Nirmoy Das" <nirmoy.das@intel.com>
Subject: Re: [RFC v2 3/3] drm/ttm/tests: Add tests for ttm_pool
Date: Thu, 29 Jun 2023 11:17:03 +0200 [thread overview]
Message-ID: <a33ea1c3-cf7f-8e8f-0ece-4b2ef299f444@amd.com> (raw)
In-Reply-To: <c7c9cdc9f14a3f14efb6cede88a1007c550ffd68.1687779215.git.karolina.stolarek@intel.com>
Am 27.06.23 um 10:32 schrieb Karolina Stolarek:
> 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>
> ---
> drivers/gpu/drm/ttm/tests/Makefile | 1 +
> drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c | 29 ++
> drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h | 5 +
> drivers/gpu/drm/ttm/tests/ttm_pool_test.c | 406 ++++++++++++++++++
> 4 files changed, 441 insertions(+)
> create mode 100644 drivers/gpu/drm/ttm/tests/ttm_pool_test.c
>
> diff --git a/drivers/gpu/drm/ttm/tests/Makefile b/drivers/gpu/drm/ttm/tests/Makefile
> index 7917805f37af..ec87c4fc1ad5 100644
> --- a/drivers/gpu/drm/ttm/tests/Makefile
> +++ b/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
> diff --git a/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c b/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c
> index d03db0405484..6ccd3e858397 100644
> --- a/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c
> +++ b/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c
> @@ -26,6 +26,35 @@ int ttm_kunit_helper_alloc_device(struct kunit *test,
> }
> EXPORT_SYMBOL_GPL(ttm_kunit_helper_alloc_device);
>
> +struct ttm_buffer_object *ttm_kunit_helper_ttm_bo_init(struct kunit *test,
> + size_t size)
> +{
> + struct ttm_test_devices_priv *priv = test->priv;
> + struct drm_gem_object *gem_obj;
> + struct ttm_buffer_object *bo;
> +
> + gem_obj = kunit_kzalloc(test, sizeof(*gem_obj), GFP_KERNEL);
> + KUNIT_ASSERT_NOT_NULL(test, gem_obj);
> +
> + drm_gem_private_object_init(priv->drm, gem_obj, size);
> +
> + bo = kunit_kzalloc(test, sizeof(*bo), GFP_KERNEL);
> + KUNIT_ASSERT_NOT_NULL(test, bo);
> +
> + bo->sg = NULL;
> + bo->base = *gem_obj;
Hui? Why that hack? That is clearly leaking the gem object.
Apart from that looks really good to me,
Christian.
> +
> + return bo;
> +}
> +EXPORT_SYMBOL_GPL(ttm_kunit_helper_ttm_bo_init);
> +
> +void ttm_kunit_helper_ttm_bo_fini(struct ttm_buffer_object *bo)
> +{
> + drm_gem_object_release(&bo->base);
> + ttm_bo_put(bo);
> +}
> +EXPORT_SYMBOL_GPL(ttm_kunit_helper_ttm_bo_fini);
> +
> int ttm_test_devices_init(struct kunit *test)
> {
> struct ttm_test_devices_priv *priv;
> diff --git a/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h b/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h
> index 69fb03b9c4d2..abb8279f18c7 100644
> --- a/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h
> +++ b/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>
> @@ -23,6 +24,10 @@ int ttm_kunit_helper_alloc_device(struct kunit *test,
> bool use_dma_alloc,
> bool use_dma32);
>
> +struct ttm_buffer_object *ttm_kunit_helper_ttm_bo_init(struct kunit *test,
> + size_t size);
> +void ttm_kunit_helper_ttm_bo_fini(struct ttm_buffer_object *bo);
> +
> int ttm_test_devices_init(struct kunit *test);
> void ttm_test_devices_fini(struct kunit *test);
>
> diff --git a/drivers/gpu/drm/ttm/tests/ttm_pool_test.c b/drivers/gpu/drm/ttm/tests/ttm_pool_test.c
> new file mode 100644
> index 000000000000..0bc6415c3067
> --- /dev/null
> +++ b/drivers/gpu/drm/ttm/tests/ttm_pool_test.c
> @@ -0,0 +1,406 @@
> +// 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;
> +};
> +
> +static struct ttm_operation_ctx simple_ctx = {
> + .interruptible = true,
> + .no_wait_gpu = false,
> +};
> +
> +static struct ttm_tt *mock_ttm_tt_init(struct kunit *test,
> + uint32_t page_flags,
> + enum ttm_caching caching,
> + size_t size)
> +{
> + struct ttm_tt *tt;
> + struct ttm_buffer_object *bo;
> + int err;
> +
> + bo = ttm_kunit_helper_ttm_bo_init(test, size);
> + KUNIT_ASSERT_NOT_NULL(test, bo);
> +
> + tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
> + KUNIT_ASSERT_NOT_NULL(test, tt);
> +
> + err = ttm_tt_init(tt, bo, page_flags, caching, 0);
> + KUNIT_ASSERT_EQ(test, err, 0);
> +
> + /* We don't need this BO later, release it */
> + ttm_kunit_helper_ttm_bo_fini(bo);
> +
> + return tt;
> +}
> +
> +static struct ttm_pool *ttm_pool_pre_populated(struct kunit *test,
> + size_t size,
> + enum ttm_caching caching)
> +{
> + struct ttm_test_devices_priv *priv = test->priv;
> + struct ttm_pool *pool;
> + struct ttm_tt *tt;
> + int err;
> + unsigned long order = __fls(size / PAGE_SIZE);
> +
> + tt = mock_ttm_tt_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, priv->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_test_devices_priv *priv = test->priv;
> + const struct ttm_pool_test_case *params = test->param_value;
> + struct ttm_tt *tt;
> + struct ttm_pool *pool;
> + struct page *fst_page, *last_page;
> + int err;
> + enum ttm_caching caching = ttm_uncached;
> + unsigned int expected_num_pages = 1 << params->order;
> + size_t size = expected_num_pages * PAGE_SIZE;
> +
> + tt = mock_ttm_tt_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, priv->dev, NUMA_NO_NODE, params->use_dma_alloc,
> + false);
> +
> + KUNIT_ASSERT_PTR_EQ(test, pool->dev, priv->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_test_devices_priv *priv = test->priv;
> + 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;
> + int err;
> + enum ttm_caching caching = ttm_uncached;
> + unsigned int expected_num_pages = 1 << params->order;
> + size_t size = expected_num_pages * PAGE_SIZE;
> +
> + tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
> + KUNIT_ASSERT_NOT_NULL(test, tt);
> +
> + bo = ttm_kunit_helper_ttm_bo_init(test, 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, priv->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 = mock_ttm_tt_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;
> + int err;
> + enum ttm_caching tt_caching = ttm_uncached;
> + enum ttm_caching pool_caching = ttm_cached;
> + size_t size = PAGE_SIZE;
> + unsigned int order = 0;
> +
> + 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 = mock_ttm_tt_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;
> + int err;
> + enum ttm_caching caching = ttm_uncached;
> + unsigned int order = 2;
> + size_t fst_size = (1 << order) * PAGE_SIZE;
> + size_t snd_size = PAGE_SIZE;
> +
> + pool = ttm_pool_pre_populated(test, fst_size, caching);
> +
> + pt_pool = &pool->caching[caching].orders[order];
> + pt_tt = &pool->caching[caching].orders[0];
> +
> + tt = mock_ttm_tt_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_test_devices_priv *priv = test->priv;
> + 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 = mock_ttm_tt_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, priv->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_test_devices_priv *priv = test->priv;
> + 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 = mock_ttm_tt_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, priv->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_test_devices_init,
> + .exit = ttm_test_devices_fini,
> + .test_cases = ttm_pool_test_cases,
> +};
> +
> +kunit_test_suites(&ttm_pool_test_suite);
> +
> +MODULE_LICENSE("GPL");
next prev parent reply other threads:[~2023-06-29 9:17 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-27 8:32 [RFC v2 0/3] Introduce KUnit tests for TTM subsystem Karolina Stolarek
2023-06-27 8:32 ` [RFC v2 1/3] drm/ttm: Introduce KUnit tests Karolina Stolarek
2023-06-29 7:50 ` Christian König
2023-06-29 10:05 ` Karolina Stolarek
2023-06-30 11:09 ` Karolina Stolarek
2023-06-30 11:18 ` Christian König
2023-06-30 12:35 ` Karolina Stolarek
2023-06-27 8:32 ` [RFC v2 2/3] drm/ttm/tests: Add tests for ttm_device Karolina Stolarek
2023-06-29 9:14 ` Christian König
2023-06-29 10:09 ` Karolina Stolarek
2023-06-27 8:32 ` [RFC v2 3/3] drm/ttm/tests: Add tests for ttm_pool Karolina Stolarek
2023-06-29 9:17 ` Christian König [this message]
2023-06-29 10:19 ` Karolina Stolarek
2023-06-29 7:39 ` [RFC v2 0/3] Introduce KUnit tests for TTM subsystem Christian König
2023-06-29 7:42 ` Karolina Stolarek
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