diff mbox series

[v2,2/2] string: Convert helpers selftest to KUnit

Message ID 20240301002650.1544829-2-keescook@chromium.org (mailing list archive)
State Superseded
Commit 64ae6a89e8681cc3e7f0286fb2d3e15a4ddb8377
Headers show
Series string: Convert selftests to KUnit | expand

Commit Message

Kees Cook March 1, 2024, 12:26 a.m. UTC 
Convert test-string_helpers.c to KUnit so it can be easily run with
everything else.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
Cc: Andy Shevchenko <andy@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: linux-hardening@vger.kernel.org
---
 MAINTAINERS                                   |   2 +-
 lib/Kconfig.debug                             |   6 +-
 lib/Makefile                                  |   2 +-
 ...tring_helpers.c => string_helpers_kunit.c} | 177 ++++++++++--------
 4 files changed, 103 insertions(+), 84 deletions(-)
 rename lib/{test-string_helpers.c => string_helpers_kunit.c} (78%)

Comments

Andy Shevchenko March 1, 2024, 11:20 a.m. UTC | #1 
On Fri, Mar 1, 2024 at 2:26 AM Kees Cook <keescook@chromium.org> wrote:
>
> Convert test-string_helpers.c to KUnit so it can be easily run with
> everything else.

...

> -#include <linux/array_size.h>
>  #include <linux/init.h>
> +#include <kunit/test.h>

I know the order is broken here, but don't make it worse, please. And
stick with one schema where to put kunit/test.h always before
everything else and somewhere else (like always after linux/*).

> +#include <linux/array_size.h>
>  #include <linux/kernel.h>
>  #include <linux/slab.h>
>  #include <linux/module.h>

...

> +static void test_string_check_buf(struct kunit *test,
> +                                 const char *name, unsigned int flags,
> +                                 char *in, size_t p,
> +                                 char *out_real, size_t q_real,
> +                                 char *out_test, size_t q_test)
>  {
> -       if (q_real == q_test && !memcmp(out_test, out_real, q_test))
> -               return true;
> +       int result;
> +
> +       KUNIT_EXPECT_EQ(test, q_real, q_test);

This needs a message.

> +       result = memcmp(out_test, out_real, q_test);

> +       KUNIT_EXPECT_EQ(test, 0, result);

Why do we need this assertion? We have a dump below to show what's wrong.

> +       if (q_real == q_test && result == 0)
> +               return;

I'm not sure this is an equivalent change. IIRC KUnit assertions do
not continue on failure. (Long time last time I run KUnit test)

>
>         pr_warn("Test '%s' failed: flags = %#x\n", name, flags);
>
> @@ -28,8 +37,6 @@ static __init bool test_string_check_buf(const char *name, unsigned int flags,
>                        out_test, q_test, true);
>         print_hex_dump(KERN_WARNING, "Got: ", DUMP_PREFIX_NONE, 16, 1,
>                        out_real, q_real, true);
> -
> -       return false;
>  }

...

> +static void
> +test_string_escape_overflow(struct kunit *test,
> +                           const char *in, int p, unsigned int flags, const char *esc,
>                             int q_test, const char *name)
>  {
>         int q_real;
>
>         q_real = string_escape_mem(in, p, NULL, 0, flags, esc);
> -       if (q_real != q_test)
> -               pr_warn("Test '%s' failed: flags = %#x, osz = 0, expected %d, got %d\n",
> -                       name, flags, q_test, q_real);
> +       KUNIT_EXPECT_EQ(test, q_real, q_test);

You killed the message, not good.

>  }

...

> +#define test_string_get_size_one(size, blk_size, exp_result10, exp_result2)      \
> +       do {                                                                     \
> +               BUILD_BUG_ON(sizeof(exp_result10) >= string_get_size_maxbuf);    \
> +               BUILD_BUG_ON(sizeof(exp_result2) >= string_get_size_maxbuf);     \

No analogous assertions in KUnit?

> +               __test_string_get_size(test, (size), (blk_size), (exp_result10), \
> +                                      (exp_result2));                           \
>         } while (0)

...

>  {
> -       if (!memcmp(res, exp, strlen(exp) + 1))
> +       int result = memcmp(res, exp, strlen(exp) + 1);

> +       KUNIT_EXPECT_EQ(test, 0, result);

As per above, what's the added value of this assertion?

> +       if (!result)
>                 return;

...

> @@ -590,65 +604,68 @@ static void __init test_string_upper_lower(void)
>         for (i = 0; i < ARRAY_SIZE(strings_upper); i++) {
>                 const char *s = strings_upper[i].in;
>                 int len = strlen(strings_upper[i].in) + 1;
> +               int result;
>
>                 dst = kmalloc(len, GFP_KERNEL);
> -               if (!dst)
> -                       return;
> +               KUNIT_ASSERT_NOT_NULL(test, dst);
>
>                 string_upper(dst, s);
> -               if (memcmp(dst, strings_upper[i].out, len)) {
> +               result = memcmp(dst, strings_upper[i].out, len);
> +               KUNIT_EXPECT_EQ(test, 0, result);

Ditto.

> +               if (result)
>                         pr_warn("Test 'string_upper' failed : expected %s, got %s!\n",
>                                 strings_upper[i].out, dst);
> -                       kfree(dst);
> -                       return;
> -               }
>                 kfree(dst);
>         }
>
>         for (i = 0; i < ARRAY_SIZE(strings_lower); i++) {
>                 const char *s = strings_lower[i].in;
>                 int len = strlen(strings_lower[i].in) + 1;
> +               int result;
>
>                 dst = kmalloc(len, GFP_KERNEL);
> -               if (!dst)
> -                       return;
> +               KUNIT_ASSERT_NOT_NULL(test, dst);
>
>                 string_lower(dst, s);
> -               if (memcmp(dst, strings_lower[i].out, len)) {
> +               result = memcmp(dst, strings_lower[i].out, len);
> +               KUNIT_EXPECT_EQ(test, 0, result);

Ditto.

> +               if (result)
>                         pr_warn("Test 'string_lower failed : : expected %s, got %s!\n",
>                                 strings_lower[i].out, dst);
> -                       kfree(dst);
> -                       return;
> -               }
>                 kfree(dst);
>         }
>  }
Kees Cook March 1, 2024, 8:29 p.m. UTC | #2 
On Fri, Mar 01, 2024 at 01:20:41PM +0200, Andy Shevchenko wrote:
> On Fri, Mar 1, 2024 at 2:26 AM Kees Cook <keescook@chromium.org> wrote:
> >
> > Convert test-string_helpers.c to KUnit so it can be easily run with
> > everything else.
> 
> ...
> 
> > -#include <linux/array_size.h>
> >  #include <linux/init.h>
> > +#include <kunit/test.h>
> 
> I know the order is broken here, but don't make it worse, please. And
> stick with one schema where to put kunit/test.h always before
> everything else and somewhere else (like always after linux/*).

Fixed.

> 
> > +#include <linux/array_size.h>
> >  #include <linux/kernel.h>
> >  #include <linux/slab.h>
> >  #include <linux/module.h>
> 
> ...
> 
> > +static void test_string_check_buf(struct kunit *test,
> > +                                 const char *name, unsigned int flags,
> > +                                 char *in, size_t p,
> > +                                 char *out_real, size_t q_real,
> > +                                 char *out_test, size_t q_test)
> >  {
> > -       if (q_real == q_test && !memcmp(out_test, out_real, q_test))
> > -               return true;
> > +       int result;
> > +
> > +       KUNIT_EXPECT_EQ(test, q_real, q_test);
> 
> This needs a message.
> 
> > +       result = memcmp(out_test, out_real, q_test);
> 
> > +       KUNIT_EXPECT_EQ(test, 0, result);
> 
> Why do we need this assertion? We have a dump below to show what's wrong.

I've improved this all around with ...STREQ and ...MEMEQ calls, and
added _MSG versions where needed to retain the prior reported test
context.

> ...
> 
> > +#define test_string_get_size_one(size, blk_size, exp_result10, exp_result2)      \
> > +       do {                                                                     \
> > +               BUILD_BUG_ON(sizeof(exp_result10) >= string_get_size_maxbuf);    \
> > +               BUILD_BUG_ON(sizeof(exp_result2) >= string_get_size_maxbuf);     \
> 
> No analogous assertions in KUnit?

It's designed for runtime testing. This is fine as-is for compile-time
asserts.

Thanks for the reviews!

-Kees
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 9f1f68cccd6a..f3f26d2d4ffb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8978,7 +8978,7 @@  F:	include/linux/string_helpers.h
 F:	lib/string.c
 F:	lib/string_kunit.c
 F:	lib/string_helpers.c
-F:	lib/test-string_helpers.c
+F:	lib/string_helpers_kunit.c
 F:	scripts/coccinelle/api/string_choices.cocci
 
 GENERIC UIO DRIVER FOR PCI DEVICES
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 406cdf353488..5429e6f170f3 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2357,8 +2357,10 @@  config STRING_KUNIT_TEST
 	depends on KUNIT
 	default KUNIT_ALL_TESTS
 
-config TEST_STRING_HELPERS
-	tristate "Test functions located in the string_helpers module at runtime"
+config STRING_HELPERS_KUNIT_TEST
+	tristate "KUnit test string helpers at runtime" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
 
 config TEST_KSTRTOX
 	tristate "Test kstrto*() family of functions at runtime"
diff --git a/lib/Makefile b/lib/Makefile
index 946277c37831..97c42e38046f 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -51,7 +51,7 @@  obj-y += bcd.o sort.o parser.o debug_locks.o random32.o \
 	 generic-radix-tree.o bitmap-str.o
 obj-$(CONFIG_STRING_KUNIT_TEST) += string_kunit.o
 obj-y += string_helpers.o
-obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o
+obj-$(CONFIG_STRING_HELPERS_KUNIT_TEST) += string_helpers_kunit.o
 obj-y += hexdump.o
 obj-$(CONFIG_TEST_HEXDUMP) += test_hexdump.o
 obj-y += kstrtox.o
diff --git a/lib/test-string_helpers.c b/lib/string_helpers_kunit.c
similarity index 78%
rename from lib/test-string_helpers.c
rename to lib/string_helpers_kunit.c
index dce67698297b..1fed4fa38f97 100644
--- a/lib/test-string_helpers.c
+++ b/lib/string_helpers_kunit.c
@@ -3,8 +3,9 @@ 
  */
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#include <linux/array_size.h>
 #include <linux/init.h>
+#include <kunit/test.h>
+#include <linux/array_size.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/module.h>
@@ -12,13 +13,21 @@ 
 #include <linux/string.h>
 #include <linux/string_helpers.h>
 
-static __init bool test_string_check_buf(const char *name, unsigned int flags,
-					 char *in, size_t p,
-					 char *out_real, size_t q_real,
-					 char *out_test, size_t q_test)
+static void test_string_check_buf(struct kunit *test,
+				  const char *name, unsigned int flags,
+				  char *in, size_t p,
+				  char *out_real, size_t q_real,
+				  char *out_test, size_t q_test)
 {
-	if (q_real == q_test && !memcmp(out_test, out_real, q_test))
-		return true;
+	int result;
+
+	KUNIT_EXPECT_EQ(test, q_real, q_test);
+
+	result = memcmp(out_test, out_real, q_test);
+	KUNIT_EXPECT_EQ(test, 0, result);
+
+	if (q_real == q_test && result == 0)
+		return;
 
 	pr_warn("Test '%s' failed: flags = %#x\n", name, flags);
 
@@ -28,8 +37,6 @@  static __init bool test_string_check_buf(const char *name, unsigned int flags,
 		       out_test, q_test, true);
 	print_hex_dump(KERN_WARNING, "Got: ", DUMP_PREFIX_NONE, 16, 1,
 		       out_real, q_real, true);
-
-	return false;
 }
 
 struct test_string {
@@ -38,7 +45,7 @@  struct test_string {
 	unsigned int flags;
 };
 
-static const struct test_string strings[] __initconst = {
+static const struct test_string strings[] = {
 	{
 		.in = "\\f\\ \\n\\r\\t\\v",
 		.out = "\f\\ \n\r\t\v",
@@ -61,8 +68,9 @@  static const struct test_string strings[] __initconst = {
 	},
 };
 
-static void __init test_string_unescape(const char *name, unsigned int flags,
-					bool inplace)
+static void test_string_unescape(struct kunit *test,
+				 const char *name, unsigned int flags,
+				 bool inplace)
 {
 	int q_real = 256;
 	char *in = kmalloc(q_real, GFP_KERNEL);
@@ -104,7 +112,7 @@  static void __init test_string_unescape(const char *name, unsigned int flags,
 		q_real = string_unescape(in, out_real, q_real, flags);
 	}
 
-	test_string_check_buf(name, flags, in, p - 1, out_real, q_real,
+	test_string_check_buf(test, name, flags, in, p - 1, out_real, q_real,
 			      out_test, q_test);
 out:
 	kfree(out_real);
@@ -124,7 +132,7 @@  struct test_string_2 {
 };
 
 #define	TEST_STRING_2_DICT_0		NULL
-static const struct test_string_2 escape0[] __initconst = {{
+static const struct test_string_2 escape0[] = {{
 	.in = "\f\\ \n\r\t\v",
 	.s1 = {{
 		.out = "\\f\\ \\n\\r\\t\\v",
@@ -222,7 +230,7 @@  static const struct test_string_2 escape0[] __initconst = {{
 }};
 
 #define	TEST_STRING_2_DICT_1		"b\\ \t\r\xCF"
-static const struct test_string_2 escape1[] __initconst = {{
+static const struct test_string_2 escape1[] = {{
 	.in = "\f\\ \n\r\t\v",
 	.s1 = {{
 		.out = "\f\\134\\040\n\\015\\011\v",
@@ -359,7 +367,7 @@  static const struct test_string_2 escape1[] __initconst = {{
 	/* terminator */
 }};
 
-static const struct test_string strings_upper[] __initconst = {
+static const struct test_string strings_upper[] = {
 	{
 		.in = "abcdefgh1234567890test",
 		.out = "ABCDEFGH1234567890TEST",
@@ -370,7 +378,7 @@  static const struct test_string strings_upper[] __initconst = {
 	},
 };
 
-static const struct test_string strings_lower[] __initconst = {
+static const struct test_string strings_lower[] = {
 	{
 		.in = "ABCDEFGH1234567890TEST",
 		.out = "abcdefgh1234567890test",
@@ -381,8 +389,8 @@  static const struct test_string strings_lower[] __initconst = {
 	},
 };
 
-static __init const char *test_string_find_match(const struct test_string_2 *s2,
-						 unsigned int flags)
+static const char *test_string_find_match(const struct test_string_2 *s2,
+					  unsigned int flags)
 {
 	const struct test_string_1 *s1 = s2->s1;
 	unsigned int i;
@@ -403,21 +411,20 @@  static __init const char *test_string_find_match(const struct test_string_2 *s2,
 	return NULL;
 }
 
-static __init void
-test_string_escape_overflow(const char *in, int p, unsigned int flags, const char *esc,
+static void
+test_string_escape_overflow(struct kunit *test,
+			    const char *in, int p, unsigned int flags, const char *esc,
 			    int q_test, const char *name)
 {
 	int q_real;
 
 	q_real = string_escape_mem(in, p, NULL, 0, flags, esc);
-	if (q_real != q_test)
-		pr_warn("Test '%s' failed: flags = %#x, osz = 0, expected %d, got %d\n",
-			name, flags, q_test, q_real);
+	KUNIT_EXPECT_EQ(test, q_real, q_test);
 }
 
-static __init void test_string_escape(const char *name,
-				      const struct test_string_2 *s2,
-				      unsigned int flags, const char *esc)
+static void test_string_escape(struct kunit *test, const char *name,
+			       const struct test_string_2 *s2,
+			       unsigned int flags, const char *esc)
 {
 	size_t out_size = 512;
 	char *out_test = kmalloc(out_size, GFP_KERNEL);
@@ -463,10 +470,10 @@  static __init void test_string_escape(const char *name,
 
 	q_real = string_escape_mem(in, p, out_real, out_size, flags, esc);
 
-	test_string_check_buf(name, flags, in, p, out_real, q_real, out_test,
+	test_string_check_buf(test, name, flags, in, p, out_real, q_real, out_test,
 			      q_test);
 
-	test_string_escape_overflow(in, p, flags, esc, q_test, name);
+	test_string_escape_overflow(test, in, p, flags, esc, q_test, name);
 
 out:
 	kfree(in);
@@ -475,22 +482,26 @@  static __init void test_string_escape(const char *name,
 }
 
 #define string_get_size_maxbuf 16
-#define test_string_get_size_one(size, blk_size, exp_result10, exp_result2)    \
-	do {                                                                   \
-		BUILD_BUG_ON(sizeof(exp_result10) >= string_get_size_maxbuf);  \
-		BUILD_BUG_ON(sizeof(exp_result2) >= string_get_size_maxbuf);   \
-		__test_string_get_size((size), (blk_size), (exp_result10),     \
-				       (exp_result2));                         \
+#define test_string_get_size_one(size, blk_size, exp_result10, exp_result2)      \
+	do {                                                                     \
+		BUILD_BUG_ON(sizeof(exp_result10) >= string_get_size_maxbuf);    \
+		BUILD_BUG_ON(sizeof(exp_result2) >= string_get_size_maxbuf);     \
+		__test_string_get_size(test, (size), (blk_size), (exp_result10), \
+				       (exp_result2));                           \
 	} while (0)
 
 
-static __init void test_string_get_size_check(const char *units,
-					      const char *exp,
-					      char *res,
-					      const u64 size,
-					      const u64 blk_size)
+static void test_string_get_size_check(struct kunit *test,
+				       const char *units,
+				       const char *exp,
+				       char *res,
+				       const u64 size,
+				       const u64 blk_size)
 {
-	if (!memcmp(res, exp, strlen(exp) + 1))
+	int result = memcmp(res, exp, strlen(exp) + 1);
+
+	KUNIT_EXPECT_EQ(test, 0, result);
+	if (!result)
 		return;
 
 	res[string_get_size_maxbuf - 1] = '\0';
@@ -501,7 +512,7 @@  static __init void test_string_get_size_check(const char *units,
 	pr_warn("expected: '%s', got '%s'\n", exp, res);
 }
 
-static __init void __strchrcut(char *dst, const char *src, const char *cut)
+static void __strchrcut(char *dst, const char *src, const char *cut)
 {
 	const char *from = src;
 	size_t len;
@@ -515,11 +526,12 @@  static __init void __strchrcut(char *dst, const char *src, const char *cut)
 	*dst = '\0';
 }
 
-static __init void __test_string_get_size_one(const u64 size, const u64 blk_size,
-					      const char *exp_result10,
-					      const char *exp_result2,
-					      enum string_size_units units,
-					      const char *cut)
+static void __test_string_get_size_one(struct kunit *test,
+				       const u64 size, const u64 blk_size,
+				       const char *exp_result10,
+				       const char *exp_result2,
+				       enum string_size_units units,
+				       const char *cut)
 {
 	char buf10[string_get_size_maxbuf];
 	char buf2[string_get_size_maxbuf];
@@ -537,13 +549,14 @@  static __init void __test_string_get_size_one(const u64 size, const u64 blk_size
 	string_get_size(size, blk_size, STRING_UNITS_10 | units, buf10, sizeof(buf10));
 	string_get_size(size, blk_size, STRING_UNITS_2 | units, buf2, sizeof(buf2));
 
-	test_string_get_size_check(prefix10, exp10, buf10, size, blk_size);
-	test_string_get_size_check(prefix2, exp2, buf2, size, blk_size);
+	test_string_get_size_check(test, prefix10, exp10, buf10, size, blk_size);
+	test_string_get_size_check(test, prefix2, exp2, buf2, size, blk_size);
 }
 
-static __init void __test_string_get_size(const u64 size, const u64 blk_size,
-					  const char *exp_result10,
-					  const char *exp_result2)
+static void __test_string_get_size(struct kunit *test,
+				   const u64 size, const u64 blk_size,
+				   const char *exp_result10,
+				   const char *exp_result2)
 {
 	struct {
 		enum string_size_units units;
@@ -557,12 +570,13 @@  static __init void __test_string_get_size(const u64 size, const u64 blk_size,
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(get_size_test_cases); i++)
-		__test_string_get_size_one(size, blk_size, exp_result10, exp_result2,
+		__test_string_get_size_one(test, size, blk_size,
+					   exp_result10, exp_result2,
 					   get_size_test_cases[i].units,
 					   get_size_test_cases[i].cut);
 }
 
-static __init void test_string_get_size(void)
+static void test_get_size(struct kunit *test)
 {
 	/* small values */
 	test_string_get_size_one(0, 512, "0 B", "0 B");
@@ -582,7 +596,7 @@  static __init void test_string_get_size(void)
 	test_string_get_size_one(4096, U64_MAX, "75.6 ZB", "64.0 ZiB");
 }
 
-static void __init test_string_upper_lower(void)
+static void test_upper_lower(struct kunit *test)
 {
 	char *dst;
 	int i;
@@ -590,65 +604,68 @@  static void __init test_string_upper_lower(void)
 	for (i = 0; i < ARRAY_SIZE(strings_upper); i++) {
 		const char *s = strings_upper[i].in;
 		int len = strlen(strings_upper[i].in) + 1;
+		int result;
 
 		dst = kmalloc(len, GFP_KERNEL);
-		if (!dst)
-			return;
+		KUNIT_ASSERT_NOT_NULL(test, dst);
 
 		string_upper(dst, s);
-		if (memcmp(dst, strings_upper[i].out, len)) {
+		result = memcmp(dst, strings_upper[i].out, len);
+		KUNIT_EXPECT_EQ(test, 0, result);
+		if (result)
 			pr_warn("Test 'string_upper' failed : expected %s, got %s!\n",
 				strings_upper[i].out, dst);
-			kfree(dst);
-			return;
-		}
 		kfree(dst);
 	}
 
 	for (i = 0; i < ARRAY_SIZE(strings_lower); i++) {
 		const char *s = strings_lower[i].in;
 		int len = strlen(strings_lower[i].in) + 1;
+		int result;
 
 		dst = kmalloc(len, GFP_KERNEL);
-		if (!dst)
-			return;
+		KUNIT_ASSERT_NOT_NULL(test, dst);
 
 		string_lower(dst, s);
-		if (memcmp(dst, strings_lower[i].out, len)) {
+		result = memcmp(dst, strings_lower[i].out, len);
+		KUNIT_EXPECT_EQ(test, 0, result);
+		if (result)
 			pr_warn("Test 'string_lower failed : : expected %s, got %s!\n",
 				strings_lower[i].out, dst);
-			kfree(dst);
-			return;
-		}
 		kfree(dst);
 	}
 }
 
-static int __init test_string_helpers_init(void)
+static void test_unescape(struct kunit *test)
 {
 	unsigned int i;
 
-	pr_info("Running tests...\n");
 	for (i = 0; i < UNESCAPE_ALL_MASK + 1; i++)
-		test_string_unescape("unescape", i, false);
-	test_string_unescape("unescape inplace",
+		test_string_unescape(test, "unescape", i, false);
+	test_string_unescape(test, "unescape inplace",
 			     get_random_u32_below(UNESCAPE_ALL_MASK + 1), true);
 
 	/* Without dictionary */
 	for (i = 0; i < ESCAPE_ALL_MASK + 1; i++)
-		test_string_escape("escape 0", escape0, i, TEST_STRING_2_DICT_0);
+		test_string_escape(test, "escape 0", escape0, i, TEST_STRING_2_DICT_0);
 
 	/* With dictionary */
 	for (i = 0; i < ESCAPE_ALL_MASK + 1; i++)
-		test_string_escape("escape 1", escape1, i, TEST_STRING_2_DICT_1);
+		test_string_escape(test, "escape 1", escape1, i, TEST_STRING_2_DICT_1);
+}
 
-	/* Test string_get_size() */
-	test_string_get_size();
+static struct kunit_case string_helpers_test_cases[] = {
+	KUNIT_CASE(test_get_size),
+	KUNIT_CASE(test_upper_lower),
+	KUNIT_CASE(test_unescape),
+	{}
+};
 
-	/* Test string upper(), string_lower() */
-	test_string_upper_lower();
+static struct kunit_suite string_helpers_test_suite = {
+	.name = "string_helpers",
+	.test_cases = string_helpers_test_cases,
+};
+
+kunit_test_suites(&string_helpers_test_suite);
 
-	return -EINVAL;
-}
-module_init(test_string_helpers_init);
 MODULE_LICENSE("Dual BSD/GPL");