Merge tag 'linux-kselftest-kunit-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull more Kunit updates from Shuah Khan:

 - add Kunit to kernel_init() and remove KUnit from init calls entirely.

   This addresses the concern that Kunit would not work correctly during
   late init phase.

 - add a linker section where KUnit can put references to its test
   suites.

   This is the first step in transitioning to dispatching all KUnit
   tests from a centralized executor rather than having each as its own
   separate late_initcall.

 - add a centralized executor to dispatch tests rather than relying on
   late_initcall to schedule each test suite separately. Centralized
   execution is for built-in tests only; modules will execute tests when
   loaded.

 - convert bitfield test to use KUnit framework

 - Documentation updates for naming guidelines and how
   kunit_test_suite() works.

 - add test plan to KUnit TAP format

* tag 'linux-kselftest-kunit-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  lib: kunit: Fix compilation test when using TEST_BIT_FIELD_COMPILE
  lib: kunit: add bitfield test conversion to KUnit
  Documentation: kunit: add a brief blurb about kunit_test_suite
  kunit: test: add test plan to KUnit TAP format
  init: main: add KUnit to kernel init
  kunit: test: create a single centralized executor for all tests
  vmlinux.lds.h: add linker section for KUnit test suites
  Documentation: kunit: Add naming guidelines

6 files changed, 101 insertions, 73 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 279926f5f843..66d44d35cc97 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2063,13 +2063,6 @@ config TEST_BITMAP
 
 	  If unsure, say N.
 
-config TEST_BITFIELD
-	tristate "Test bitfield functions at runtime"
-	help
-	  Enable this option to test the bitfield functions at boot.
-
-	  If unsure, say N.
-
 config TEST_UUID
 	tristate "Test functions located in the uuid module at runtime"
 
@@ -2219,6 +2212,22 @@ config TEST_SYSCTL
 
 	  If unsure, say N.
 
+config BITFIELD_KUNIT
+	tristate "KUnit test bitfield functions at runtime"
+	depends on KUNIT
+	help
+	  Enable this option to test the bitfield functions at boot.
+
+	  KUnit tests run during boot and output the results to the debug log
+	  in TAP format (http://testanything.org/). Only useful for kernel devs
+	  running the KUnit test harness, and not intended for inclusion into a
+	  production build.
+
+	  For more information on KUnit and unit tests in general please refer
+	  to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+	  If unsure, say N.
+
 config SYSCTL_KUNIT_TEST
 	tristate "KUnit test for sysctl" if !KUNIT_ALL_TESTS
 	depends on KUNIT
diff --git a/lib/Makefile b/lib/Makefile
index 1c7577b2e86a..ce45af50983a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -87,7 +87,6 @@ obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o
 obj-$(CONFIG_TEST_PRINTF) += test_printf.o
 obj-$(CONFIG_TEST_BITMAP) += test_bitmap.o
 obj-$(CONFIG_TEST_STRSCPY) += test_strscpy.o
-obj-$(CONFIG_TEST_BITFIELD) += test_bitfield.o
 obj-$(CONFIG_TEST_UUID) += test_uuid.o
 obj-$(CONFIG_TEST_XARRAY) += test_xarray.o
 obj-$(CONFIG_TEST_PARMAN) += test_parman.o
@@ -349,6 +348,7 @@ obj-$(CONFIG_OBJAGG) += objagg.o
 obj-$(CONFIG_PLDMFW) += pldmfw/
 
 # KUnit tests
+obj-$(CONFIG_BITFIELD_KUNIT) += bitfield_kunit.o
 obj-$(CONFIG_LIST_KUNIT_TEST) += list-test.o
 obj-$(CONFIG_LINEAR_RANGES_TEST) += test_linear_ranges.o
 obj-$(CONFIG_BITS_TEST) += test_bits.o
diff --git a/lib/test_bitfield.c b/lib/bitfield_kunit.c
index 5b8f4108662d..1473d8b4bf0f 100644
--- a/lib/test_bitfield.c
+++ b/lib/bitfield_kunit.c
@@ -5,8 +5,7 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#include <linux/kernel.h>
-#include <linux/module.h>
+#include <kunit/test.h>
 #include <linux/bitfield.h>
 
 #define CHECK_ENC_GET_U(tp, v, field, res) do {				\
@@ -14,13 +13,11 @@
 			u##tp _res;					\
 									\
 			_res = u##tp##_encode_bits(v, field);		\
-			if (_res != res) {				\
-				pr_warn("u" #tp "_encode_bits(" #v ", " #field ") is 0x%llx != " #res "\n",\
-					(u64)_res);			\
-				return -EINVAL;				\
-			}						\
-			if (u##tp##_get_bits(_res, field) != v)		\
-				return -EINVAL;				\
+			KUNIT_ASSERT_FALSE_MSG(context, _res != res,	\
+				       "u" #tp "_encode_bits(" #v ", " #field ") is 0x%llx != " #res "\n",	\
+				       (u64)_res);			\
+			KUNIT_ASSERT_FALSE(context,			\
+				   u##tp##_get_bits(_res, field) != v);	\
 		}							\
 	} while (0)
 
@@ -29,14 +26,13 @@
 			__le##tp _res;					\
 									\
 			_res = le##tp##_encode_bits(v, field);		\
-			if (_res != cpu_to_le##tp(res)) {		\
-				pr_warn("le" #tp "_encode_bits(" #v ", " #field ") is 0x%llx != 0x%llx\n",\
-					(u64)le##tp##_to_cpu(_res),	\
-					(u64)(res));			\
-				return -EINVAL;				\
-			}						\
-			if (le##tp##_get_bits(_res, field) != v)	\
-				return -EINVAL;				\
+			KUNIT_ASSERT_FALSE_MSG(context,			\
+				       _res != cpu_to_le##tp(res),	\
+				       "le" #tp "_encode_bits(" #v ", " #field ") is 0x%llx != 0x%llx",\
+				       (u64)le##tp##_to_cpu(_res),	\
+				       (u64)(res));			\
+			KUNIT_ASSERT_FALSE(context,			\
+				   le##tp##_get_bits(_res, field) != v);\
 		}							\
 	} while (0)
 
@@ -45,14 +41,13 @@
 			__be##tp _res;					\
 									\
 			_res = be##tp##_encode_bits(v, field);		\
-			if (_res != cpu_to_be##tp(res)) {		\
-				pr_warn("be" #tp "_encode_bits(" #v ", " #field ") is 0x%llx != 0x%llx\n",\
-					(u64)be##tp##_to_cpu(_res),	\
-					(u64)(res));			\
-				return -EINVAL;				\
-			}						\
-			if (be##tp##_get_bits(_res, field) != v)	\
-				return -EINVAL;				\
+			KUNIT_ASSERT_FALSE_MSG(context,			\
+				       _res != cpu_to_be##tp(res),	\
+				       "be" #tp "_encode_bits(" #v ", " #field ") is 0x%llx != 0x%llx",	\
+				       (u64)be##tp##_to_cpu(_res),	\
+				       (u64)(res));			\
+			KUNIT_ASSERT_FALSE(context,			\
+				   be##tp##_get_bits(_res, field) != v);\
 		}							\
 	} while (0)
 
@@ -62,7 +57,7 @@
 		CHECK_ENC_GET_BE(tp, v, field, res);			\
 	} while (0)
 
-static int test_constants(void)
+static void __init test_bitfields_constants(struct kunit *context)
 {
 	/*
 	 * NOTE
@@ -95,19 +90,17 @@ static int test_constants(void)
 	CHECK_ENC_GET(64,  7, 0x00f0000000000000ull, 0x0070000000000000ull);
 	CHECK_ENC_GET(64, 14, 0x0f00000000000000ull, 0x0e00000000000000ull);
 	CHECK_ENC_GET(64, 15, 0xf000000000000000ull, 0xf000000000000000ull);
-
-	return 0;
 }
 
 #define CHECK(tp, mask) do {						\
 		u64 v;							\
 									\
 		for (v = 0; v < 1 << hweight32(mask); v++)		\
-			if (tp##_encode_bits(v, mask) != v << __ffs64(mask)) \
-				return -EINVAL;				\
+			KUNIT_ASSERT_FALSE(context,			\
+				tp##_encode_bits(v, mask) != v << __ffs64(mask));\
 	} while (0)
 
-static int test_variables(void)
+static void __init test_bitfields_variables(struct kunit *context)
 {
 	CHECK(u8, 0x0f);
 	CHECK(u8, 0xf0);
@@ -130,39 +123,32 @@ static int test_variables(void)
 	CHECK(u64, 0x000000007f000000ull);
 	CHECK(u64, 0x0000000018000000ull);
 	CHECK(u64, 0x0000001f8000000ull);
-
-	return 0;
 }
 
-static int __init test_bitfields(void)
-{
-	int ret = test_constants();
-
-	if (ret) {
-		pr_warn("constant tests failed!\n");
-		return ret;
-	}
-
-	ret = test_variables();
-	if (ret) {
-		pr_warn("variable tests failed!\n");
-		return ret;
-	}
-
 #ifdef TEST_BITFIELD_COMPILE
+static void __init test_bitfields_compile(struct kunit *context)
+{
 	/* these should fail compilation */
 	CHECK_ENC_GET(16, 16, 0x0f00, 0x1000);
 	u32_encode_bits(7, 0x06000000);
 
 	/* this should at least give a warning */
 	u16_encode_bits(0, 0x60000);
+}
 #endif
 
-	pr_info("tests passed\n");
+static struct kunit_case __refdata bitfields_test_cases[] = {
+	KUNIT_CASE(test_bitfields_constants),
+	KUNIT_CASE(test_bitfields_variables),
+	{}
+};
 
-	return 0;
-}
-module_init(test_bitfields)
+static struct kunit_suite bitfields_test_suite = {
+	.name = "bitfields",
+	.test_cases = bitfields_test_cases,
+};
+
+kunit_test_suites(&bitfields_test_suite);
 
 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
 MODULE_LICENSE("GPL");
diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile
index 724b94311ca3..c49f4ffb6273 100644
--- a/lib/kunit/Makefile
+++ b/lib/kunit/Makefile
@@ -3,7 +3,8 @@ obj-$(CONFIG_KUNIT) +=			kunit.o
 kunit-objs +=				test.o \
 					string-stream.o \
 					assert.o \
-					try-catch.o
+					try-catch.o \
+					executor.o
 
 ifeq ($(CONFIG_KUNIT_DEBUGFS),y)
 kunit-objs +=				debugfs.o
diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
new file mode 100644
index 000000000000..a95742a4ece7
--- /dev/null
+++ b/lib/kunit/executor.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <kunit/test.h>
+
+/*
+ * These symbols point to the .kunit_test_suites section and are defined in
+ * include/asm-generic/vmlinux.lds.h, and consequently must be extern.
+ */
+extern struct kunit_suite * const * const __kunit_suites_start[];
+extern struct kunit_suite * const * const __kunit_suites_end[];
+
+#if IS_BUILTIN(CONFIG_KUNIT)
+
+static void kunit_print_tap_header(void)
+{
+	struct kunit_suite * const * const *suites, * const *subsuite;
+	int num_of_suites = 0;
+
+	for (suites = __kunit_suites_start;
+	     suites < __kunit_suites_end;
+	     suites++)
+		for (subsuite = *suites; *subsuite != NULL; subsuite++)
+			num_of_suites++;
+
+	pr_info("TAP version 14\n");
+	pr_info("1..%d\n", num_of_suites);
+}
+
+int kunit_run_all_tests(void)
+{
+	struct kunit_suite * const * const *suites;
+
+	kunit_print_tap_header();
+
+	for (suites = __kunit_suites_start;
+	     suites < __kunit_suites_end;
+	     suites++)
+			__kunit_test_suites_init(*suites);
+
+	return 0;
+}
+
+#endif /* IS_BUILTIN(CONFIG_KUNIT) */
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index dcc35fd30d95..750704abe89a 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -16,16 +16,6 @@
 #include "string-stream.h"
 #include "try-catch-impl.h"
 
-static void kunit_print_tap_version(void)
-{
-	static bool kunit_has_printed_tap_version;
-
-	if (!kunit_has_printed_tap_version) {
-		pr_info("TAP version 14\n");
-		kunit_has_printed_tap_version = true;
-	}
-}
-
 /*
  * Append formatted message to log, size of which is limited to
  * KUNIT_LOG_SIZE bytes (including null terminating byte).
@@ -65,7 +55,6 @@ EXPORT_SYMBOL_GPL(kunit_suite_num_test_cases);
 
 static void kunit_print_subtest_start(struct kunit_suite *suite)
 {
-	kunit_print_tap_version();
 	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "# Subtest: %s",
 		  suite->name);
 	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "1..%zd",
@@ -381,7 +370,7 @@ static void kunit_init_suite(struct kunit_suite *suite)
 	kunit_debugfs_create_suite(suite);
 }
 
-int __kunit_test_suites_init(struct kunit_suite **suites)
+int __kunit_test_suites_init(struct kunit_suite * const * const suites)
 {
 	unsigned int i;