From 0a756853586ce185ee1bb9ccbe5ec03e103e594f Mon Sep 17 00:00:00 2001 From: Brendan Higgins Date: Mon, 23 Sep 2019 02:02:32 -0700 Subject: [PATCH] kunit: test: add test resource management API Create a common API for test managed resources like memory and test objects. A lot of times a test will want to set up infrastructure to be used in test cases; this could be anything from just wanting to allocate some memory to setting up a driver stack; this defines facilities for creating "test resources" which are managed by the test infrastructure and are automatically cleaned up at the conclusion of the test. Signed-off-by: Brendan Higgins Reviewed-by: Greg Kroah-Hartman Reviewed-by: Logan Gunthorpe Reviewed-by: Stephen Boyd Signed-off-by: Shuah Khan --- include/kunit/test.h | 187 +++++++++++++++++++++++++++++++++++++++++++ lib/kunit/test.c | 163 +++++++++++++++++++++++++++++++++++++ 2 files changed, 350 insertions(+) diff --git a/include/kunit/test.h b/include/kunit/test.h index e30d1bf2fb68..6781c756f11b 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -9,8 +9,72 @@ #ifndef _KUNIT_TEST_H #define _KUNIT_TEST_H +#include #include +struct kunit_resource; + +typedef int (*kunit_resource_init_t)(struct kunit_resource *, void *); +typedef void (*kunit_resource_free_t)(struct kunit_resource *); + +/** + * struct kunit_resource - represents a *test managed resource* + * @allocation: for the user to store arbitrary data. + * @free: a user supplied function to free the resource. Populated by + * kunit_alloc_resource(). + * + * Represents a *test managed resource*, a resource which will automatically be + * cleaned up at the end of a test case. + * + * Example: + * + * .. code-block:: c + * + * struct kunit_kmalloc_params { + * size_t size; + * gfp_t gfp; + * }; + * + * static int kunit_kmalloc_init(struct kunit_resource *res, void *context) + * { + * struct kunit_kmalloc_params *params = context; + * res->allocation = kmalloc(params->size, params->gfp); + * + * if (!res->allocation) + * return -ENOMEM; + * + * return 0; + * } + * + * static void kunit_kmalloc_free(struct kunit_resource *res) + * { + * kfree(res->allocation); + * } + * + * void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp) + * { + * struct kunit_kmalloc_params params; + * struct kunit_resource *res; + * + * params.size = size; + * params.gfp = gfp; + * + * res = kunit_alloc_resource(test, kunit_kmalloc_init, + * kunit_kmalloc_free, ¶ms); + * if (res) + * return res->allocation; + * + * return NULL; + * } + */ +struct kunit_resource { + void *allocation; + kunit_resource_free_t free; + + /* private: internal use only. */ + struct list_head node; +}; + struct kunit; /** @@ -114,6 +178,13 @@ struct kunit { * with the test case have terminated. */ bool success; /* Read only after test_case finishes! */ + spinlock_t lock; /* Guards all mutable test state. */ + /* + * Because resources is a list that may be updated multiple times (with + * new resources) from any thread associated with a test case, we must + * protect it with some type of lock. + */ + struct list_head resources; /* Protected by lock. */ }; void kunit_init_test(struct kunit *test, const char *name); @@ -147,6 +218,122 @@ int kunit_run_tests(struct kunit_suite *suite); } \ late_initcall(kunit_suite_init##suite) +/* + * Like kunit_alloc_resource() below, but returns the struct kunit_resource + * object that contains the allocation. This is mostly for testing purposes. + */ +struct kunit_resource *kunit_alloc_and_get_resource(struct kunit *test, + kunit_resource_init_t init, + kunit_resource_free_t free, + gfp_t internal_gfp, + void *context); + +/** + * kunit_alloc_resource() - Allocates a *test managed resource*. + * @test: The test context object. + * @init: a user supplied function to initialize the resource. + * @free: a user supplied function to free the resource. + * @internal_gfp: gfp to use for internal allocations, if unsure, use GFP_KERNEL + * @context: for the user to pass in arbitrary data to the init function. + * + * Allocates a *test managed resource*, a resource which will automatically be + * cleaned up at the end of a test case. See &struct kunit_resource for an + * example. + * + * NOTE: KUnit needs to allocate memory for each kunit_resource object. You must + * specify an @internal_gfp that is compatible with the use context of your + * resource. + */ +static inline void *kunit_alloc_resource(struct kunit *test, + kunit_resource_init_t init, + kunit_resource_free_t free, + gfp_t internal_gfp, + void *context) +{ + struct kunit_resource *res; + + res = kunit_alloc_and_get_resource(test, init, free, internal_gfp, + context); + + if (res) + return res->allocation; + + return NULL; +} + +typedef bool (*kunit_resource_match_t)(struct kunit *test, + const void *res, + void *match_data); + +/** + * kunit_resource_instance_match() - Match a resource with the same instance. + * @test: Test case to which the resource belongs. + * @res: The data stored in kunit_resource->allocation. + * @match_data: The resource pointer to match against. + * + * An instance of kunit_resource_match_t that matches a resource whose + * allocation matches @match_data. + */ +static inline bool kunit_resource_instance_match(struct kunit *test, + const void *res, + void *match_data) +{ + return res == match_data; +} + +/** + * kunit_resource_destroy() - Find a kunit_resource and destroy it. + * @test: Test case to which the resource belongs. + * @match: Match function. Returns whether a given resource matches @match_data. + * @free: Must match free on the kunit_resource to free. + * @match_data: Data passed into @match. + * + * Free the latest kunit_resource of @test for which @free matches the + * kunit_resource_free_t associated with the resource and for which @match + * returns true. + * + * RETURNS: + * 0 if kunit_resource is found and freed, -ENOENT if not found. + */ +int kunit_resource_destroy(struct kunit *test, + kunit_resource_match_t match, + kunit_resource_free_t free, + void *match_data); + +/** + * kunit_kmalloc() - Like kmalloc() except the allocation is *test managed*. + * @test: The test context object. + * @size: The size in bytes of the desired memory. + * @gfp: flags passed to underlying kmalloc(). + * + * Just like `kmalloc(...)`, except the allocation is managed by the test case + * and is automatically cleaned up after the test case concludes. See &struct + * kunit_resource for more information. + */ +void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp); + +/** + * kunit_kfree() - Like kfree except for allocations managed by KUnit. + * @test: The test case to which the resource belongs. + * @ptr: The memory allocation to free. + */ +void kunit_kfree(struct kunit *test, const void *ptr); + +/** + * kunit_kzalloc() - Just like kunit_kmalloc(), but zeroes the allocation. + * @test: The test context object. + * @size: The size in bytes of the desired memory. + * @gfp: flags passed to underlying kmalloc(). + * + * See kzalloc() and kunit_kmalloc() for more information. + */ +static inline void *kunit_kzalloc(struct kunit *test, size_t size, gfp_t gfp) +{ + return kunit_kmalloc(test, size, gfp | __GFP_ZERO); +} + +void kunit_cleanup(struct kunit *test); + void __printf(3, 4) kunit_printk(const char *level, const struct kunit *test, const char *fmt, ...); diff --git a/lib/kunit/test.c b/lib/kunit/test.c index d3dda359f99b..68b1037ab74d 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -122,6 +122,8 @@ static void kunit_print_test_case_ok_not_ok(struct kunit_case *test_case, void kunit_init_test(struct kunit *test, const char *name) { + spin_lock_init(&test->lock); + INIT_LIST_HEAD(&test->resources); test->name = name; test->success = true; } @@ -153,6 +155,8 @@ static void kunit_run_case(struct kunit_suite *suite, if (suite->exit) suite->exit(&test); + kunit_cleanup(&test); + test_case->success = test.success; } @@ -173,6 +177,165 @@ int kunit_run_tests(struct kunit_suite *suite) return 0; } +struct kunit_resource *kunit_alloc_and_get_resource(struct kunit *test, + kunit_resource_init_t init, + kunit_resource_free_t free, + gfp_t internal_gfp, + void *context) +{ + struct kunit_resource *res; + int ret; + + res = kzalloc(sizeof(*res), internal_gfp); + if (!res) + return NULL; + + ret = init(res, context); + if (ret) + return NULL; + + res->free = free; + spin_lock(&test->lock); + list_add_tail(&res->node, &test->resources); + spin_unlock(&test->lock); + + return res; +} + +static void kunit_resource_free(struct kunit *test, struct kunit_resource *res) +{ + res->free(res); + kfree(res); +} + +static struct kunit_resource *kunit_resource_find(struct kunit *test, + kunit_resource_match_t match, + kunit_resource_free_t free, + void *match_data) +{ + struct kunit_resource *resource; + + lockdep_assert_held(&test->lock); + + list_for_each_entry_reverse(resource, &test->resources, node) { + if (resource->free != free) + continue; + if (match(test, resource->allocation, match_data)) + return resource; + } + + return NULL; +} + +static struct kunit_resource *kunit_resource_remove( + struct kunit *test, + kunit_resource_match_t match, + kunit_resource_free_t free, + void *match_data) +{ + struct kunit_resource *resource; + + spin_lock(&test->lock); + resource = kunit_resource_find(test, match, free, match_data); + if (resource) + list_del(&resource->node); + spin_unlock(&test->lock); + + return resource; +} + +int kunit_resource_destroy(struct kunit *test, + kunit_resource_match_t match, + kunit_resource_free_t free, + void *match_data) +{ + struct kunit_resource *resource; + + resource = kunit_resource_remove(test, match, free, match_data); + + if (!resource) + return -ENOENT; + + kunit_resource_free(test, resource); + return 0; +} + +struct kunit_kmalloc_params { + size_t size; + gfp_t gfp; +}; + +static int kunit_kmalloc_init(struct kunit_resource *res, void *context) +{ + struct kunit_kmalloc_params *params = context; + + res->allocation = kmalloc(params->size, params->gfp); + if (!res->allocation) + return -ENOMEM; + + return 0; +} + +static void kunit_kmalloc_free(struct kunit_resource *res) +{ + kfree(res->allocation); +} + +void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp) +{ + struct kunit_kmalloc_params params = { + .size = size, + .gfp = gfp + }; + + return kunit_alloc_resource(test, + kunit_kmalloc_init, + kunit_kmalloc_free, + gfp, + ¶ms); +} + +void kunit_kfree(struct kunit *test, const void *ptr) +{ + int rc; + + rc = kunit_resource_destroy(test, + kunit_resource_instance_match, + kunit_kmalloc_free, + (void *)ptr); + + WARN_ON(rc); +} + +void kunit_cleanup(struct kunit *test) +{ + struct kunit_resource *resource; + + /* + * test->resources is a stack - each allocation must be freed in the + * reverse order from which it was added since one resource may depend + * on another for its entire lifetime. + * Also, we cannot use the normal list_for_each constructs, even the + * safe ones because *arbitrary* nodes may be deleted when + * kunit_resource_free is called; the list_for_each_safe variants only + * protect against the current node being deleted, not the next. + */ + while (true) { + spin_lock(&test->lock); + if (list_empty(&test->resources)) { + spin_unlock(&test->lock); + break; + } + resource = list_last_entry(&test->resources, + struct kunit_resource, + node); + list_del(&resource->node); + spin_unlock(&test->lock); + + kunit_resource_free(test, resource); + } +} + void kunit_printk(const char *level, const struct kunit *test, const char *fmt, ...)