Merge tag 'linux-kselftest-kunit-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull Kunit updates from Shuah Khan:

 - documentation update and fix to kunit_tool to parse diagnostic
   messages correctly from David Gow

 - Support for Parameterized Testing and fs/ext4 test updates to use
   KUnit parameterized testing feature from Arpitha Raghunandan

 - Helper to derive file names depending on --build_dir argument from
   Andy Shevchenko

* tag 'linux-kselftest-kunit-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  fs: ext4: Modify inode-test.c to use KUnit parameterized testing feature
  kunit: Support for Parameterized Testing
  kunit: kunit_tool: Correctly parse diagnostic messages
  Documentation: kunit: provide guidance for testing many inputs
  kunit: Introduce get_file_path() helper

1 files changed, 51 insertions, 0 deletions

diff --git a/include/kunit/test.h b/include/kunit/test.h
index df60be7e22ca..49601c4b98b8 100644
--- a/include/kunit/test.h
+++ b/include/kunit/test.h
@@ -94,6 +94,9 @@ struct kunit;
 /* Size of log associated with test. */
 #define KUNIT_LOG_SIZE	512
 
+/* Maximum size of parameter description string. */
+#define KUNIT_PARAM_DESC_SIZE 128
+
 /*
  * TAP specifies subtest stream indentation of 4 spaces, 8 spaces for a
  * sub-subtest.  See the "Subtests" section in
@@ -107,6 +110,7 @@ struct kunit;
  *
  * @run_case: the function representing the actual test case.
  * @name:     the name of the test case.
+ * @generate_params: the generator function for parameterized tests.
  *
  * A test case is a function with the signature,
  * ``void (*)(struct kunit *)``
@@ -141,6 +145,7 @@ struct kunit;
 struct kunit_case {
 	void (*run_case)(struct kunit *test);
 	const char *name;
+	const void* (*generate_params)(const void *prev, char *desc);
 
 	/* private: internal use only. */
 	bool success;
@@ -164,6 +169,27 @@ static inline char *kunit_status_to_string(bool status)
 #define KUNIT_CASE(test_name) { .run_case = test_name, .name = #test_name }
 
 /**
+ * KUNIT_CASE_PARAM - A helper for creation a parameterized &struct kunit_case
+ *
+ * @test_name: a reference to a test case function.
+ * @gen_params: a reference to a parameter generator function.
+ *
+ * The generator function::
+ *
+ *	const void* gen_params(const void *prev, char *desc)
+ *
+ * is used to lazily generate a series of arbitrarily typed values that fit into
+ * a void*. The argument @prev is the previously returned value, which should be
+ * used to derive the next value; @prev is set to NULL on the initial generator
+ * call. When no more values are available, the generator must return NULL.
+ * Optionally write a string into @desc (size of KUNIT_PARAM_DESC_SIZE)
+ * describing the parameter.
+ */
+#define KUNIT_CASE_PARAM(test_name, gen_params)			\
+		{ .run_case = test_name, .name = #test_name,	\
+		  .generate_params = gen_params }
+
+/**
  * struct kunit_suite - describes a related collection of &struct kunit_case
  *
  * @name:	the name of the test. Purely informational.
@@ -208,6 +234,10 @@ struct kunit {
 	const char *name; /* Read only after initialization! */
 	char *log; /* Points at case log after initialization */
 	struct kunit_try_catch try_catch;
+	/* param_value is the current parameter value for a test case. */
+	const void *param_value;
+	/* param_index stores the index of the parameter in parameterized tests. */
+	int param_index;
 	/*
 	 * success starts as true, and may only be set to false during a
 	 * test case; thus, it is safe to update this across multiple
@@ -1742,4 +1772,25 @@ do {									       \
 						fmt,			       \
 						##__VA_ARGS__)
 
+/**
+ * KUNIT_ARRAY_PARAM() - Define test parameter generator from an array.
+ * @name:  prefix for the test parameter generator function.
+ * @array: array of test parameters.
+ * @get_desc: function to convert param to description; NULL to use default
+ *
+ * Define function @name_gen_params which uses @array to generate parameters.
+ */
+#define KUNIT_ARRAY_PARAM(name, array, get_desc)						\
+	static const void *name##_gen_params(const void *prev, char *desc)			\
+	{											\
+		typeof((array)[0]) *__next = prev ? ((typeof(__next)) prev) + 1 : (array);	\
+		if (__next - (array) < ARRAY_SIZE((array))) {					\
+			void (*__get_desc)(typeof(__next), char *) = get_desc;			\
+			if (__get_desc)								\
+				__get_desc(__next, desc);					\
+			return __next;								\
+		}										\
+		return NULL;									\
+	}
+
 #endif /* _KUNIT_TEST_H */