Re: [PATCH v3 1/4] drm/ttm/tests: Add tests for ttm_resource and ttm_sys_man

[Karolina Stolarek <karolina.stolarek@xxxxxxxxx>]

On 18.09.2023 13:48, Karolina Stolarek wrote:
> On 12.09.2023 14:54, Christian König wrote:
> > Am 12.09.23 um 13:49 schrieb Karolina Stolarek:
> > > Test initialization of ttm_resource using different memory domains.
> > > Add tests for a system memory manager and functions that can be
> > > tested without a fully-featured resource manager. Update
> > > ttm_bo_kunit_init() to initialize BO's kref and reservation object.
> > > Export ttm_resource_alloc symbol for test purposes only.
> > >
> > > Signed-off-by: Karolina Stolarek <karolina.stolarek@xxxxxxxxx>
> > > ---
> > >   drivers/gpu/drm/ttm/tests/Makefile            |   1 +
> > >   drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c |  23 ++
> > >   drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h |   4 +
> > >   drivers/gpu/drm/ttm/tests/ttm_resource_test.c | 335 ++++++++++++++++++
> > >   drivers/gpu/drm/ttm/ttm_resource.c            |   3 +
> > >   5 files changed, 366 insertions(+)
> > >   create mode 100644 drivers/gpu/drm/ttm/tests/ttm_resource_test.c
> > >
> > > diff --git a/drivers/gpu/drm/ttm/tests/Makefile 
> > > b/drivers/gpu/drm/ttm/tests/Makefile
> > > index ec87c4fc1ad5..c92fe2052ef6 100644
> > > --- a/drivers/gpu/drm/ttm/tests/Makefile
> > > +++ b/drivers/gpu/drm/ttm/tests/Makefile
> > > @@ -3,4 +3,5 @@
> > >   obj-$(CONFIG_DRM_TTM_KUNIT_TEST) += \
> > >           ttm_device_test.o \
> > >           ttm_pool_test.o \
> > > +        ttm_resource_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 81661d8827aa..eccc59b981f8 100644
> > > --- a/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c
> > > +++ b/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c
> > > @@ -38,10 +38,33 @@ struct ttm_buffer_object 
> > > *ttm_bo_kunit_init(struct kunit *test,
> > >       bo->base = gem_obj;
> > >       bo->bdev = devs->ttm_dev;
> > > +    kref_init(&bo->kref);
> > > +
> > > +    dma_resv_init(&bo->base._resv);
> > > +    bo->base.resv = &bo->base._resv;
> > > +
> >
> > I'm really wondering if we shouldn't now initialize the GEM object 
> > properly?
> >
> > That would also initialize the reservation object if I remember 
> > correctly.
>
> Do you mean by using drm_gem_object_init()?

I tried initializing bo.base with drm_gem_object_init() and it's looking 
good, but one check in that function makes testing of "Misaligned size" 
subtest of ttm_tt_init_basic impossible:

BUG_ON((size & (PAGE_SIZE - 1)) != 0);

I wanted to test if ttm_tt_init properly calculates the number of pages, 
but it looks like in the normal circuimstances it already gets a GEM 
object of a size that is page-aligned. Would you prefer to write this 
subtest as a separate test with a dummy misaligned GEM object, or to 
delete this subtest altogether?

Many thanks,
Karolina

> > The solution with EXPORT_SYMBOL_FOR_TESTS_ONLY looks really nice I 
> > think and apart from that I can't see anything obviously wrong either, 
> > but I only skimmed over the code.
>
> I'm also glad with EXPORT_SYMBOL_FOR_TESTS_ONLY solution, it's much 
> better now. Right, you can take a closer look at the next version. I'll 
> try to get an actual GEM object here, if you think that's feasible.
>
> All the best,
> Karolina
>
> > Regards,
> > Christian.
> >
> > >       return bo;
> > >   }
> > >   EXPORT_SYMBOL_GPL(ttm_bo_kunit_init);
> > > +struct ttm_place *ttm_place_kunit_init(struct kunit *test,
> > > +                       uint32_t mem_type, uint32_t flags,
> > > +                       size_t size)
> > > +{
> > > +    struct ttm_place *place;
> > > +
> > > +    place = kunit_kzalloc(test, sizeof(*place), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, place);
> > > +
> > > +    place->mem_type = mem_type;
> > > +    place->flags = flags;
> > > +    place->fpfn = size >> PAGE_SHIFT;
> > > +    place->lpfn = place->fpfn + (size >> PAGE_SHIFT);
> > > +
> > > +    return place;
> > > +}
> > > +EXPORT_SYMBOL_GPL(ttm_place_kunit_init);
> > > +
> > >   struct ttm_test_devices *ttm_test_devices_basic(struct kunit *test)
> > >   {
> > >       struct ttm_test_devices *devs;
> > > diff --git a/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h 
> > > b/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h
> > > index e261e3660d0b..f38140f93c05 100644
> > > --- a/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h
> > > +++ b/drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.h
> > > @@ -8,6 +8,7 @@
> > >   #include <drm/drm_drv.h>
> > >   #include <drm/ttm/ttm_device.h>
> > >   #include <drm/ttm/ttm_bo.h>
> > > +#include <drm/ttm/ttm_placement.h>
> > >   #include <drm/drm_kunit_helpers.h>
> > >   #include <kunit/test.h>
> > > @@ -28,6 +29,9 @@ int ttm_device_kunit_init(struct ttm_test_devices 
> > > *priv,
> > >   struct ttm_buffer_object *ttm_bo_kunit_init(struct kunit *test,
> > >                           struct ttm_test_devices *devs,
> > >                           size_t size);
> > > +struct ttm_place *ttm_place_kunit_init(struct kunit *test,
> > > +                       uint32_t mem_type, uint32_t flags,
> > > +                       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);
> > > diff --git a/drivers/gpu/drm/ttm/tests/ttm_resource_test.c 
> > > b/drivers/gpu/drm/ttm/tests/ttm_resource_test.c
> > > new file mode 100644
> > > index 000000000000..851cdc43dc37
> > > --- /dev/null
> > > +++ b/drivers/gpu/drm/ttm/tests/ttm_resource_test.c
> > > @@ -0,0 +1,335 @@
> > > +// SPDX-License-Identifier: GPL-2.0 AND MIT
> > > +/*
> > > + * Copyright © 2023 Intel Corporation
> > > + */
> > > +#include <drm/ttm/ttm_resource.h>
> > > +
> > > +#include "ttm_kunit_helpers.h"
> > > +
> > > +#define RES_SIZE        SZ_4K
> > > +#define TTM_PRIV_DUMMY_REG    (TTM_NUM_MEM_TYPES - 1)
> > > +
> > > +struct ttm_resource_test_case {
> > > +    const char *description;
> > > +    uint32_t mem_type;
> > > +    uint32_t flags;
> > > +};
> > > +
> > > +struct ttm_resource_test_priv {
> > > +    struct ttm_test_devices *devs;
> > > +    struct ttm_buffer_object *bo;
> > > +    struct ttm_place *place;
> > > +};
> > > +
> > > +static const struct ttm_resource_manager_func 
> > > ttm_resource_manager_mock_funcs = { };
> > > +
> > > +static int ttm_resource_test_init(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv;
> > > +
> > > +    priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, priv);
> > > +
> > > +    priv->devs = ttm_test_devices_all(test);
> > > +    KUNIT_ASSERT_NOT_NULL(test, priv->devs);
> > > +
> > > +    test->priv = priv;
> > > +
> > > +    return 0;
> > > +}
> > > +
> > > +static void ttm_resource_test_fini(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +
> > > +    ttm_test_devices_put(test, priv->devs);
> > > +}
> > > +
> > > +static void ttm_init_test_mocks(struct kunit *test,
> > > +                struct ttm_resource_test_priv *priv,
> > > +                uint32_t mem_type, uint32_t flags)
> > > +{
> > > +    size_t size = RES_SIZE;
> > > +
> > > +    /* Make sure we have what we need for a good BO mock */
> > > +    KUNIT_ASSERT_NOT_NULL(test, priv->devs->ttm_dev);
> > > +
> > > +    priv->bo = ttm_bo_kunit_init(test, priv->devs, size);
> > > +    priv->place = ttm_place_kunit_init(test, mem_type, flags, size);
> > > +}
> > > +
> > > +static void ttm_init_test_manager(struct kunit *test,
> > > +                  struct ttm_resource_test_priv *priv,
> > > +                  uint32_t mem_type)
> > > +{
> > > +    struct ttm_device *ttm_dev = priv->devs->ttm_dev;
> > > +    struct ttm_resource_manager *man;
> > > +    size_t size = SZ_16K;
> > > +
> > > +    man = kunit_kzalloc(test, sizeof(*man), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, man);
> > > +
> > > +    man->use_tt = false;
> > > +    man->func = &ttm_resource_manager_mock_funcs;
> > > +
> > > +    ttm_resource_manager_init(man, ttm_dev, size);
> > > +    ttm_set_driver_manager(ttm_dev, mem_type, man);
> > > +    ttm_resource_manager_set_used(man, true);
> > > +}
> > > +
> > > +static const struct ttm_resource_test_case ttm_resource_cases[] = {
> > > +    {
> > > +        .description = "Init resource in TTM_PL_SYSTEM",
> > > +        .mem_type = TTM_PL_SYSTEM,
> > > +    },
> > > +    {
> > > +        .description = "Init resource in TTM_PL_VRAM",
> > > +        .mem_type = TTM_PL_VRAM,
> > > +    },
> > > +    {
> > > +        .description = "Init resource in a private placement",
> > > +        .mem_type = TTM_PRIV_DUMMY_REG,
> > > +    },
> > > +    {
> > > +        .description = "Init resource in TTM_PL_SYSTEM, set 
> > > placement flags",
> > > +        .mem_type = TTM_PL_SYSTEM,
> > > +        .flags = TTM_PL_FLAG_TOPDOWN,
> > > +    },
> > > +};
> > > +
> > > +static void ttm_resource_case_desc(const struct 
> > > ttm_resource_test_case *t, char *desc)
> > > +{
> > > +    strscpy(desc, t->description, KUNIT_PARAM_DESC_SIZE);
> > > +}
> > > +
> > > +KUNIT_ARRAY_PARAM(ttm_resource, ttm_resource_cases, 
> > > ttm_resource_case_desc);
> > > +
> > > +static void ttm_resource_init_basic(struct kunit *test)
> > > +{
> > > +    const struct ttm_resource_test_case *params = test->param_value;
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +    struct ttm_resource *res;
> > > +    struct ttm_buffer_object *bo;
> > > +    struct ttm_place *place;
> > > +    struct ttm_resource_manager *man;
> > > +    uint64_t expected_usage;
> > > +
> > > +    ttm_init_test_mocks(test, priv, params->mem_type, params->flags);
> > > +    bo = priv->bo;
> > > +    place = priv->place;
> > > +
> > > +    if (params->mem_type > TTM_PL_SYSTEM)
> > > +        ttm_init_test_manager(test, priv, params->mem_type);
> > > +
> > > +    res = kunit_kzalloc(test, sizeof(*res), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, res);
> > > +
> > > +    man = ttm_manager_type(priv->devs->ttm_dev, place->mem_type);
> > > +    expected_usage = man->usage + RES_SIZE;
> > > +
> > > +    KUNIT_ASSERT_TRUE(test, list_empty(&man->lru[bo->priority]));
> > > +
> > > +    ttm_resource_init(bo, place, res);
> > > +
> > > +    KUNIT_ASSERT_EQ(test, res->start, 0);
> > > +    KUNIT_ASSERT_EQ(test, res->size, RES_SIZE);
> > > +    KUNIT_ASSERT_EQ(test, res->mem_type, place->mem_type);
> > > +    KUNIT_ASSERT_EQ(test, res->placement, place->flags);
> > > +    KUNIT_ASSERT_PTR_EQ(test, res->bo, bo);
> > > +
> > > +    KUNIT_ASSERT_NULL(test, res->bus.addr);
> > > +    KUNIT_ASSERT_EQ(test, res->bus.offset, 0);
> > > +    KUNIT_ASSERT_FALSE(test, res->bus.is_iomem);
> > > +    KUNIT_ASSERT_EQ(test, res->bus.caching, ttm_cached);
> > > +    KUNIT_ASSERT_EQ(test, man->usage, expected_usage);
> > > +
> > > +    KUNIT_ASSERT_TRUE(test, list_is_singular(&man->lru[bo->priority]));
> > > +
> > > +    ttm_resource_fini(man, res);
> > > +}
> > > +
> > > +static void ttm_resource_init_pinned(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +    struct ttm_resource *res;
> > > +    struct ttm_buffer_object *bo;
> > > +    struct ttm_place *place;
> > > +    struct ttm_resource_manager *man;
> > > +
> > > +    ttm_init_test_mocks(test, priv, TTM_PL_SYSTEM, 0);
> > > +    bo = priv->bo;
> > > +    place = priv->place;
> > > +
> > > +    man = ttm_manager_type(priv->devs->ttm_dev, place->mem_type);
> > > +
> > > +    res = kunit_kzalloc(test, sizeof(*res), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, res);
> > > +    KUNIT_ASSERT_TRUE(test, list_empty(&bo->bdev->pinned));
> > > +
> > > +    dma_resv_lock(bo->base.resv, NULL);
> > > +    ttm_bo_pin(bo);
> > > +    ttm_resource_init(bo, place, res);
> > > +    KUNIT_ASSERT_TRUE(test, list_is_singular(&bo->bdev->pinned));
> > > +
> > > +    ttm_bo_unpin(bo);
> > > +    ttm_resource_fini(man, res);
> > > +    dma_resv_unlock(bo->base.resv);
> > > +
> > > +    KUNIT_ASSERT_TRUE(test, list_empty(&bo->bdev->pinned));
> > > +}
> > > +
> > > +static void ttm_resource_fini_basic(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +    struct ttm_resource *res;
> > > +    struct ttm_buffer_object *bo;
> > > +    struct ttm_place *place;
> > > +    struct ttm_resource_manager *man;
> > > +
> > > +    ttm_init_test_mocks(test, priv, TTM_PL_SYSTEM, 0);
> > > +    bo = priv->bo;
> > > +    place = priv->place;
> > > +
> > > +    man = ttm_manager_type(priv->devs->ttm_dev, place->mem_type);
> > > +
> > > +    res = kunit_kzalloc(test, sizeof(*res), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, res);
> > > +
> > > +    ttm_resource_init(bo, place, res);
> > > +    ttm_resource_fini(man, res);
> > > +
> > > +    KUNIT_ASSERT_TRUE(test, list_empty(&res->lru));
> > > +    KUNIT_ASSERT_EQ(test, man->usage, 0);
> > > +}
> > > +
> > > +static void ttm_resource_manager_init_basic(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +    struct ttm_resource_manager *man;
> > > +    size_t size = SZ_16K;
> > > +
> > > +    man = kunit_kzalloc(test, sizeof(*man), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, man);
> > > +
> > > +    ttm_resource_manager_init(man, priv->devs->ttm_dev, size);
> > > +
> > > +    KUNIT_ASSERT_PTR_EQ(test, man->bdev, priv->devs->ttm_dev);
> > > +    KUNIT_ASSERT_EQ(test, man->size, size);
> > > +    KUNIT_ASSERT_EQ(test, man->usage, 0);
> > > +    KUNIT_ASSERT_NULL(test, man->move);
> > > +    KUNIT_ASSERT_NOT_NULL(test, &man->move_lock);
> > > +
> > > +    for (int i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
> > > +        KUNIT_ASSERT_TRUE(test, list_empty(&man->lru[i]));
> > > +}
> > > +
> > > +static void ttm_resource_manager_usage_basic(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +    struct ttm_resource *res;
> > > +    struct ttm_buffer_object *bo;
> > > +    struct ttm_place *place;
> > > +    struct ttm_resource_manager *man;
> > > +    uint64_t actual_usage;
> > > +
> > > +    ttm_init_test_mocks(test, priv, TTM_PL_SYSTEM, 
> > > TTM_PL_FLAG_TOPDOWN);
> > > +    bo = priv->bo;
> > > +    place = priv->place;
> > > +
> > > +    res = kunit_kzalloc(test, sizeof(*res), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, res);
> > > +
> > > +    man = ttm_manager_type(priv->devs->ttm_dev, place->mem_type);
> > > +
> > > +    ttm_resource_init(bo, place, res);
> > > +    actual_usage = ttm_resource_manager_usage(man);
> > > +
> > > +    KUNIT_ASSERT_EQ(test, actual_usage, RES_SIZE);
> > > +
> > > +    ttm_resource_fini(man, res);
> > > +}
> > > +
> > > +static void ttm_resource_manager_set_used_basic(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +    struct ttm_resource_manager *man;
> > > +
> > > +    man = ttm_manager_type(priv->devs->ttm_dev, TTM_PL_SYSTEM);
> > > +    KUNIT_ASSERT_TRUE(test, man->use_type);
> > > +
> > > +    ttm_resource_manager_set_used(man, false);
> > > +    KUNIT_ASSERT_FALSE(test, man->use_type);
> > > +}
> > > +
> > > +static void ttm_sys_man_alloc_basic(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +    struct ttm_resource_manager *man;
> > > +    struct ttm_buffer_object *bo;
> > > +    struct ttm_place *place;
> > > +    struct ttm_resource *res;
> > > +    uint32_t mem_type = TTM_PL_SYSTEM;
> > > +    int ret;
> > > +
> > > +    ttm_init_test_mocks(test, priv, mem_type, 0);
> > > +    bo = priv->bo;
> > > +    place = priv->place;
> > > +
> > > +    man = ttm_manager_type(priv->devs->ttm_dev, mem_type);
> > > +    ret = man->func->alloc(man, bo, place, &res);
> > > +
> > > +    KUNIT_ASSERT_EQ(test, ret, 0);
> > > +    KUNIT_ASSERT_EQ(test, res->size, RES_SIZE);
> > > +    KUNIT_ASSERT_EQ(test, res->mem_type, mem_type);
> > > +    KUNIT_ASSERT_PTR_EQ(test, res->bo, bo);
> > > +
> > > +    ttm_resource_fini(man, res);
> > > +}
> > > +
> > > +static void ttm_sys_man_free_basic(struct kunit *test)
> > > +{
> > > +    struct ttm_resource_test_priv *priv = test->priv;
> > > +    struct ttm_resource_manager *man;
> > > +    struct ttm_buffer_object *bo;
> > > +    struct ttm_place *place;
> > > +    struct ttm_resource *res;
> > > +    uint32_t mem_type = TTM_PL_SYSTEM;
> > > +
> > > +    ttm_init_test_mocks(test, priv, mem_type, 0);
> > > +    bo = priv->bo;
> > > +    place = priv->place;
> > > +
> > > +    res = kunit_kzalloc(test, sizeof(*res), GFP_KERNEL);
> > > +    KUNIT_ASSERT_NOT_NULL(test, res);
> > > +
> > > +    ttm_resource_alloc(bo, place, &res);
> > > +
> > > +    man = ttm_manager_type(priv->devs->ttm_dev, mem_type);
> > > +    man->func->free(man, res);
> > > +
> > > +    KUNIT_ASSERT_TRUE(test, list_empty(&man->lru[bo->priority]));
> > > +    KUNIT_ASSERT_EQ(test, man->usage, 0);
> > > +}
> > > +
> > > +static struct kunit_case ttm_resource_test_cases[] = {
> > > +    KUNIT_CASE_PARAM(ttm_resource_init_basic, ttm_resource_gen_params),
> > > +    KUNIT_CASE(ttm_resource_init_pinned),
> > > +    KUNIT_CASE(ttm_resource_fini_basic),
> > > +    KUNIT_CASE(ttm_resource_manager_init_basic),
> > > +    KUNIT_CASE(ttm_resource_manager_usage_basic),
> > > +    KUNIT_CASE(ttm_resource_manager_set_used_basic),
> > > +    KUNIT_CASE(ttm_sys_man_alloc_basic),
> > > +    KUNIT_CASE(ttm_sys_man_free_basic),
> > > +    {}
> > > +};
> > > +
> > > +static struct kunit_suite ttm_resource_test_suite = {
> > > +    .name = "ttm_resource",
> > > +    .init = ttm_resource_test_init,
> > > +    .exit = ttm_resource_test_fini,
> > > +    .test_cases = ttm_resource_test_cases,
> > > +};
> > > +
> > > +kunit_test_suites(&ttm_resource_test_suite);
> > > +
> > > +MODULE_LICENSE("GPL");
> > > diff --git a/drivers/gpu/drm/ttm/ttm_resource.c 
> > > b/drivers/gpu/drm/ttm/ttm_resource.c
> > > index 46ff9c75bb12..02b96d23fdb9 100644
> > > --- a/drivers/gpu/drm/ttm/ttm_resource.c
> > > +++ b/drivers/gpu/drm/ttm/ttm_resource.c
> > > @@ -30,6 +30,8 @@
> > >   #include <drm/ttm/ttm_placement.h>
> > >   #include <drm/ttm/ttm_resource.h>
> > > +#include <drm/drm_util.h>
> > > +
> > >   /**
> > >    * ttm_lru_bulk_move_init - initialize a bulk move structure
> > >    * @bulk: the structure to init
> > > @@ -240,6 +242,7 @@ int ttm_resource_alloc(struct ttm_buffer_object *bo,
> > >       spin_unlock(&bo->bdev->lru_lock);
> > >       return 0;
> > >   }
> > > +EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_resource_alloc);
> > >   void ttm_resource_free(struct ttm_buffer_object *bo, struct 
> > > ttm_resource **res)
> > >   {