[PATCH v4 0/3] printf: convert self-test to KUnit

[PATCH v4 0/3] printf: convert self-test to KUnit

[Tamir Duberstein]

This is one of just 3 remaining "Test Module" kselftests (the others
being bitmap and scanf), the rest having been converted to KUnit.

I tested this using:

$ tools/testing/kunit/kunit.py run --arch arm64 --make_options LLVM=1 printf

I have also sent out a series converting scanf[0].

Link: https://lore.kernel.org/all/20250204-scanf-kunit-convert-v3-0-386d7c3ee714@gmail.com/T/#u [0]

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
Changes in v4:
- Add patch "implicate test line in failure messages".
- Rebase on linux-next, move scanf_kunit.c into lib/tests/.
- Link to v3: https://lore.kernel.org/r/20250210-printf-kunit-convert-v3-0-ee6ac5500f5e@gmail.com

Changes in v3:
- Remove extraneous trailing newlines from failure messages.
- Replace `pr_warn` with `kunit_warn`.
- Drop arch changes.
- Remove KUnit boilerplate from CONFIG_PRINTF_KUNIT_TEST help text.
- Restore `total_tests` counting.
- Remove tc_fail macro in last patch.
- Link to v2: https://lore.kernel.org/r/20250207-printf-kunit-convert-v2-0-057b23860823@gmail.com

Changes in v2:
- Incorporate code review from prior work[0] by Arpitha Raghunandan.
- Link to v1: https://lore.kernel.org/r/20250204-printf-kunit-convert-v1-0-ecf1b846a4de@gmail.com

Link: https://lore.kernel.org/lkml/20200817043028.76502-1-98.arpi@gmail.com/t/#u [0]

---
Tamir Duberstein (3):
      printf: convert self-test to KUnit
      printf: break kunit into test cases
      printf: implicate test line in failure messages

 Documentation/core-api/printk-formats.rst   |   4 +-
 MAINTAINERS                                 |   2 +-
 lib/Kconfig.debug                           |  12 +-
 lib/Makefile                                |   1 -
 lib/tests/Makefile                          |   1 +
 lib/{test_printf.c => tests/printf_kunit.c} | 437 ++++++++++++----------------
 tools/testing/selftests/lib/config          |   1 -
 tools/testing/selftests/lib/printf.sh       |   4 -
 8 files changed, 200 insertions(+), 262 deletions(-)
---
base-commit: 7b7a883c7f4de1ee5040bd1c32aabaafde54d209
change-id: 20250131-printf-kunit-convert-fd4012aa2ec6

Best regards,
-- 
Tamir Duberstein <tamird@gmail.com>

[PATCH v4 1/3] printf: convert self-test to KUnit

[Tamir Duberstein]

Convert the printf() self-test to a KUnit test.

In the interest of keeping the patch reasonably-sized this doesn't
refactor the tests into proper parameterized tests - it's all one big
test case.

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
 Documentation/core-api/printk-formats.rst   |   4 +-
 MAINTAINERS                                 |   2 +-
 lib/Kconfig.debug                           |  12 +-
 lib/Makefile                                |   1 -
 lib/tests/Makefile                          |   1 +
 lib/{test_printf.c => tests/printf_kunit.c} | 188 +++++++++++++++-------------
 tools/testing/selftests/lib/config          |   1 -
 tools/testing/selftests/lib/printf.sh       |   4 -
 8 files changed, 117 insertions(+), 96 deletions(-)

diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst
index ecccc0473da9..4bdc394e86af 100644
--- a/Documentation/core-api/printk-formats.rst
+++ b/Documentation/core-api/printk-formats.rst
@@ -661,7 +661,7 @@ Do *not* use it from C.
 Thanks
 ======
 
-If you add other %p extensions, please extend <lib/test_printf.c> with
-one or more test cases, if at all feasible.
+If you add other %p extensions, please extend <lib/tests/printf_kunit.c>
+with one or more test cases, if at all feasible.
 
 Thank you for your cooperation and attention.
diff --git a/MAINTAINERS b/MAINTAINERS
index 92fc0eca7061..d85366e22ff6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -25466,8 +25466,8 @@ R:	Sergey Senozhatsky <senozhatsky@chromium.org>
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux.git
 F:	Documentation/core-api/printk-formats.rst
-F:	lib/test_printf.c
 F:	lib/test_scanf.c
+F:	lib/tests/printf_kunit.c
 F:	lib/vsprintf.c
 
 VT1211 HARDWARE MONITOR DRIVER
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 85b95d645b10..0c27745dff56 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2436,6 +2436,15 @@ config ASYNC_RAID6_TEST
 config TEST_HEXDUMP
 	tristate "Test functions located in the hexdump module at runtime"
 
+config PRINTF_KUNIT_TEST
+	tristate "KUnit test printf() family of functions at runtime" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  Enable this option to test the printf functions at runtime.
+
+	  If unsure, say N.
+
 config STRING_KUNIT_TEST
 	tristate "KUnit test string functions at runtime" if !KUNIT_ALL_TESTS
 	depends on KUNIT
@@ -2449,9 +2458,6 @@ config STRING_HELPERS_KUNIT_TEST
 config TEST_KSTRTOX
 	tristate "Test kstrto*() family of functions at runtime"
 
-config TEST_PRINTF
-	tristate "Test printf() family of functions at runtime"
-
 config TEST_SCANF
 	tristate "Test scanf() family of functions at runtime"
 
diff --git a/lib/Makefile b/lib/Makefile
index 961aef91d493..f31e6a3100ba 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -77,7 +77,6 @@ obj-$(CONFIG_TEST_RHASHTABLE) += test_rhashtable.o
 obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_keys.o
 obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o
 obj-$(CONFIG_TEST_DYNAMIC_DEBUG) += test_dynamic_debug.o
-obj-$(CONFIG_TEST_PRINTF) += test_printf.o
 obj-$(CONFIG_TEST_SCANF) += test_scanf.o
 
 obj-$(CONFIG_TEST_BITMAP) += test_bitmap.o
diff --git a/lib/tests/Makefile b/lib/tests/Makefile
index 8961fbcff7a4..183c6a838a5d 100644
--- a/lib/tests/Makefile
+++ b/lib/tests/Makefile
@@ -30,6 +30,7 @@ obj-$(CONFIG_LINEAR_RANGES_TEST) += test_linear_ranges.o
 obj-$(CONFIG_MEMCPY_KUNIT_TEST) += memcpy_kunit.o
 CFLAGS_overflow_kunit.o = $(call cc-disable-warning, tautological-constant-out-of-range-compare)
 obj-$(CONFIG_OVERFLOW_KUNIT_TEST) += overflow_kunit.o
+obj-$(CONFIG_PRINTF_KUNIT_TEST) += printf_kunit.o
 obj-$(CONFIG_SIPHASH_KUNIT_TEST) += siphash_kunit.o
 obj-$(CONFIG_SLUB_KUNIT_TEST) += slub_kunit.o
 obj-$(CONFIG_TEST_SORT) += test_sort.o
diff --git a/lib/test_printf.c b/lib/tests/printf_kunit.c
similarity index 87%
rename from lib/test_printf.c
rename to lib/tests/printf_kunit.c
index 59dbe4f9a4cb..287bbfb61148 100644
--- a/lib/test_printf.c
+++ b/lib/tests/printf_kunit.c
@@ -3,9 +3,7 @@
  * Test cases for printf facility.
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/init.h>
+#include <kunit/test.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/printk.h>
@@ -25,8 +23,6 @@
 
 #include <linux/property.h>
 
-#include "../tools/testing/selftests/kselftest_module.h"
-
 #define BUF_SIZE 256
 #define PAD_SIZE 16
 #define FILL_CHAR '$'
@@ -37,12 +33,17 @@
 	block \
 	__diag_pop();
 
-KSTM_MODULE_GLOBALS();
+static unsigned int total_tests;
+
+static char *test_buffer;
+static char *alloced_buffer;
+
+static struct kunit *kunittest;
 
-static char *test_buffer __initdata;
-static char *alloced_buffer __initdata;
+#define tc_fail(fmt, ...) \
+	KUNIT_FAIL(kunittest, fmt, ##__VA_ARGS__)
 
-static int __printf(4, 0) __init
+static void __printf(4, 0)
 do_test(int bufsize, const char *expect, int elen,
 	const char *fmt, va_list ap)
 {
@@ -57,52 +58,50 @@ do_test(int bufsize, const char *expect, int elen,
 	va_end(aq);
 
 	if (ret != elen) {
-		pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n",
+		tc_fail("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d",
 			bufsize, fmt, ret, elen);
-		return 1;
+		return;
 	}
 
 	if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) {
-		pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer\n", bufsize, fmt);
-		return 1;
+		tc_fail("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer",
+			bufsize, fmt);
+		return;
 	}
 
 	if (!bufsize) {
 		if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_SIZE)) {
-			pr_warn("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer\n",
-				fmt);
-			return 1;
+			tc_fail("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer", fmt);
 		}
-		return 0;
+		return;
 	}
 
 	written = min(bufsize-1, elen);
 	if (test_buffer[written]) {
-		pr_warn("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer\n",
+		tc_fail("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer",
 			bufsize, fmt);
-		return 1;
+		return;
 	}
 
 	if (memchr_inv(test_buffer + written + 1, FILL_CHAR, bufsize - (written + 1))) {
-		pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator\n",
+		tc_fail("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator",
 			bufsize, fmt);
-		return 1;
+		return;
 	}
 
 	if (memchr_inv(test_buffer + bufsize, FILL_CHAR, BUF_SIZE + PAD_SIZE - bufsize)) {
-		pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote beyond buffer\n", bufsize, fmt);
-		return 1;
+		tc_fail("vsnprintf(buf, %d, \"%s\", ...) wrote beyond buffer", bufsize, fmt);
+		return;
 	}
 
 	if (memcmp(test_buffer, expect, written)) {
-		pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n",
+		tc_fail("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'",
 			bufsize, fmt, test_buffer, written, expect);
-		return 1;
+		return;
 	}
-	return 0;
 }
 
-static void __printf(3, 4) __init
+static void __printf(3, 4)
 __test(const char *expect, int elen, const char *fmt, ...)
 {
 	va_list ap;
@@ -110,9 +109,8 @@ __test(const char *expect, int elen, const char *fmt, ...)
 	char *p;
 
 	if (elen >= BUF_SIZE) {
-		pr_err("error in test suite: expected output length %d too long. Format was '%s'.\n",
-		       elen, fmt);
-		failed_tests++;
+		tc_fail("error in test suite: expected output length %d too long. Format was '%s'.",
+			elen, fmt);
 		return;
 	}
 
@@ -124,19 +122,18 @@ __test(const char *expect, int elen, const char *fmt, ...)
 	 * enough and 0), and then we also test that kvasprintf would
 	 * be able to print it as expected.
 	 */
-	failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap);
+	do_test(BUF_SIZE, expect, elen, fmt, ap);
 	rand = get_random_u32_inclusive(1, elen + 1);
 	/* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */
-	failed_tests += do_test(rand, expect, elen, fmt, ap);
-	failed_tests += do_test(0, expect, elen, fmt, ap);
+	do_test(rand, expect, elen, fmt, ap);
+	do_test(0, expect, elen, fmt, ap);
 
 	p = kvasprintf(GFP_KERNEL, fmt, ap);
 	if (p) {
 		total_tests++;
 		if (memcmp(p, expect, elen+1)) {
-			pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n",
+			tc_fail("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'",
 				fmt, p, expect);
-			failed_tests++;
 		}
 		kfree(p);
 	}
@@ -146,7 +143,7 @@ __test(const char *expect, int elen, const char *fmt, ...)
 #define test(expect, fmt, ...)					\
 	__test(expect, strlen(expect), fmt, ##__VA_ARGS__)
 
-static void __init
+static void
 test_basic(void)
 {
 	/* Work around annoying "warning: zero-length gnu_printf format string". */
@@ -158,7 +155,7 @@ test_basic(void)
 	__test("xxx\0yyy", 7, "xxx%cyyy", '\0');
 }
 
-static void __init
+static void
 test_number(void)
 {
 	test("0x1234abcd  ", "%#-12x", 0x1234abcd);
@@ -180,7 +177,7 @@ test_number(void)
 	test("00|0|0|0|0", "%.2d|%.1d|%.0d|%.*d|%1.0d", 0, 0, 0, 0, 0, 0);
 }
 
-static void __init
+static void
 test_string(void)
 {
 	test("", "%s%.0s", "", "123");
@@ -218,7 +215,7 @@ test_string(void)
 #define ZEROS "00000000"	/* hex 32 zero bits */
 #define ONES "ffffffff"		/* hex 32 one bits */
 
-static int __init
+static int
 plain_format(void)
 {
 	char buf[PLAIN_BUF_SIZE];
@@ -230,7 +227,7 @@ plain_format(void)
 		return -1;
 
 	if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) {
-		pr_warn("crng possibly not yet initialized. plain 'p' buffer contains \"%s\"",
+		kunit_warn(kunittest, "crng possibly not yet initialized. plain 'p' buffer contains \"%s\"",
 			PTR_VAL_NO_CRNG);
 		return 0;
 	}
@@ -250,7 +247,7 @@ plain_format(void)
 #define ZEROS ""
 #define ONES ""
 
-static int __init
+static int
 plain_format(void)
 {
 	/* Format is implicitly tested for 32 bit machines by plain_hash() */
@@ -259,7 +256,7 @@ plain_format(void)
 
 #endif	/* BITS_PER_LONG == 64 */
 
-static int __init
+static int
 plain_hash_to_buffer(const void *p, char *buf, size_t len)
 {
 	int nchars;
@@ -270,7 +267,7 @@ plain_hash_to_buffer(const void *p, char *buf, size_t len)
 		return -1;
 
 	if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) {
-		pr_warn("crng possibly not yet initialized. plain 'p' buffer contains \"%s\"",
+		kunit_warn(kunittest, "crng possibly not yet initialized. plain 'p' buffer contains \"%s\"",
 			PTR_VAL_NO_CRNG);
 		return 0;
 	}
@@ -278,7 +275,7 @@ plain_hash_to_buffer(const void *p, char *buf, size_t len)
 	return 0;
 }
 
-static int __init
+static int
 plain_hash(void)
 {
 	char buf[PLAIN_BUF_SIZE];
@@ -298,32 +295,29 @@ plain_hash(void)
  * We can't use test() to test %p because we don't know what output to expect
  * after an address is hashed.
  */
-static void __init
+static void
 plain(void)
 {
 	int err;
 
 	if (no_hash_pointers) {
-		pr_warn("skipping plain 'p' tests");
-		skipped_tests += 2;
+		kunit_warn(kunittest, "skipping plain 'p' tests");
 		return;
 	}
 
 	err = plain_hash();
 	if (err) {
-		pr_warn("plain 'p' does not appear to be hashed\n");
-		failed_tests++;
+		tc_fail("plain 'p' does not appear to be hashed");
 		return;
 	}
 
 	err = plain_format();
 	if (err) {
-		pr_warn("hashing plain 'p' has unexpected format\n");
-		failed_tests++;
+		tc_fail("hashing plain 'p' has unexpected format");
 	}
 }
 
-static void __init
+static void
 test_hashed(const char *fmt, const void *p)
 {
 	char buf[PLAIN_BUF_SIZE];
@@ -343,7 +337,7 @@ test_hashed(const char *fmt, const void *p)
 /*
  * NULL pointers aren't hashed.
  */
-static void __init
+static void
 null_pointer(void)
 {
 	test(ZEROS "00000000", "%p", NULL);
@@ -354,7 +348,7 @@ null_pointer(void)
 /*
  * Error pointers aren't hashed.
  */
-static void __init
+static void
 error_pointer(void)
 {
 	test(ONES "fffffff5", "%p", ERR_PTR(-11));
@@ -364,7 +358,7 @@ error_pointer(void)
 
 #define PTR_INVALID ((void *)0x000000ab)
 
-static void __init
+static void
 invalid_pointer(void)
 {
 	test_hashed("%p", PTR_INVALID);
@@ -372,18 +366,18 @@ invalid_pointer(void)
 	test("(efault)", "%pE", PTR_INVALID);
 }
 
-static void __init
+static void
 symbol_ptr(void)
 {
 }
 
-static void __init
+static void
 kernel_ptr(void)
 {
 	/* We can't test this without access to kptr_restrict. */
 }
 
-static void __init
+static void
 struct_resource(void)
 {
 	struct resource test_resource = {
@@ -432,7 +426,7 @@ struct_resource(void)
 	     "%pR", &test_resource);
 }
 
-static void __init
+static void
 struct_range(void)
 {
 	struct range test_range = DEFINE_RANGE(0xc0ffee00ba5eba11,
@@ -448,17 +442,17 @@ struct_range(void)
 	     "%pra", &test_range);
 }
 
-static void __init
+static void
 addr(void)
 {
 }
 
-static void __init
+static void
 escaped_str(void)
 {
 }
 
-static void __init
+static void
 hex_string(void)
 {
 	const char buf[3] = {0xc0, 0xff, 0xee};
@@ -469,7 +463,7 @@ hex_string(void)
 	     "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf);
 }
 
-static void __init
+static void
 mac(void)
 {
 	const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05};
@@ -481,7 +475,7 @@ mac(void)
 	test("057afcd6482d", "%pmR", addr);
 }
 
-static void __init
+static void
 ip4(void)
 {
 	struct sockaddr_in sa;
@@ -496,19 +490,19 @@ ip4(void)
 	test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa);
 }
 
-static void __init
+static void
 ip6(void)
 {
 }
 
-static void __init
+static void
 ip(void)
 {
 	ip4();
 	ip6();
 }
 
-static void __init
+static void
 uuid(void)
 {
 	const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
@@ -520,7 +514,7 @@ uuid(void)
 	test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid);
 }
 
-static struct dentry test_dentry[4] __initdata = {
+static struct dentry test_dentry[4] = {
 	{ .d_parent = &test_dentry[0],
 	  .d_name = QSTR_INIT(test_dentry[0].d_iname, 3),
 	  .d_iname = "foo" },
@@ -535,7 +529,7 @@ static struct dentry test_dentry[4] __initdata = {
 	  .d_iname = "romeo" },
 };
 
-static void __init
+static void
 dentry(void)
 {
 	test("foo", "%pd", &test_dentry[0]);
@@ -556,12 +550,12 @@ dentry(void)
 	test("  bravo/alfa|  bravo/alfa", "%12pd2|%*pd2", &test_dentry[2], 12, &test_dentry[2]);
 }
 
-static void __init
+static void
 struct_va_format(void)
 {
 }
 
-static void __init
+static void
 time_and_date(void)
 {
 	/* 1543210543 */
@@ -595,12 +589,12 @@ time_and_date(void)
 	test("15:32:23|0119-00-04", "%ptTtrs|%ptTdrs", &t, &t);
 }
 
-static void __init
+static void
 struct_clk(void)
 {
 }
 
-static void __init
+static void
 large_bitmap(void)
 {
 	const int nbits = 1 << 16;
@@ -614,7 +608,7 @@ large_bitmap(void)
 	bitmap_free(bits);
 }
 
-static void __init
+static void
 bitmap(void)
 {
 	DECLARE_BITMAP(bits, 20);
@@ -637,7 +631,7 @@ bitmap(void)
 	large_bitmap();
 }
 
-static void __init
+static void
 netdev_features(void)
 {
 }
@@ -663,7 +657,7 @@ static const struct page_flags_test pft[] = {
 	 "%#x", "kasantag"},
 };
 
-static void __init
+static void
 page_flags_test(int section, int node, int zone, int last_cpupid,
 		int kasan_tag, unsigned long flags, const char *name,
 		char *cmp_buf)
@@ -701,7 +695,7 @@ page_flags_test(int section, int node, int zone, int last_cpupid,
 	test(cmp_buf, "%pGp", &flags);
 }
 
-static void __init
+static void
 flags(void)
 {
 	unsigned long flags;
@@ -749,7 +743,7 @@ flags(void)
 	kfree(cmp_buffer);
 }
 
-static void __init fwnode_pointer(void)
+static void fwnode_pointer(void)
 {
 	const struct software_node first = { .name = "first" };
 	const struct software_node second = { .name = "second", .parent = &first };
@@ -763,7 +757,7 @@ static void __init fwnode_pointer(void)
 
 	rval = software_node_register_node_group(group);
 	if (rval) {
-		pr_warn("cannot register softnodes; rval %d\n", rval);
+		kunit_warn(kunittest, "cannot register softnodes; rval %d", rval);
 		return;
 	}
 
@@ -776,7 +770,7 @@ static void __init fwnode_pointer(void)
 	software_node_unregister_node_group(group);
 }
 
-static void __init fourcc_pointer(void)
+static void fourcc_pointer(void)
 {
 	struct {
 		u32 code;
@@ -793,7 +787,7 @@ static void __init fourcc_pointer(void)
 		test(try[i].str, "%p4cc", &try[i].code);
 }
 
-static void __init
+static void
 errptr(void)
 {
 	test("-1234", "%pe", ERR_PTR(-1234));
@@ -813,7 +807,7 @@ errptr(void)
 #endif
 }
 
-static void __init
+static void
 test_pointer(void)
 {
 	plain();
@@ -842,13 +836,15 @@ test_pointer(void)
 	fourcc_pointer();
 }
 
-static void __init selftest(void)
+static void printf_test(struct kunit *test)
 {
 	alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL);
 	if (!alloced_buffer)
 		return;
 	test_buffer = alloced_buffer + PAD_SIZE;
 
+	kunittest = test;
+
 	test_basic();
 	test_number();
 	test_string();
@@ -857,7 +853,31 @@ static void __init selftest(void)
 	kfree(alloced_buffer);
 }
 
-KSTM_MODULE_LOADERS(test_printf);
+static int printf_suite_init(struct kunit_suite *suite)
+{
+	total_tests = 0;
+	return 0;
+}
+
+static void printf_suite_exit(struct kunit_suite *suite)
+{
+	kunit_info(suite, "ran %u tests", total_tests);
+}
+
+static struct kunit_case printf_test_cases[] = {
+	KUNIT_CASE(printf_test),
+	{}
+};
+
+static struct kunit_suite printf_test_suite = {
+	.name = "printf",
+	.suite_init = printf_suite_init,
+	.suite_exit = printf_suite_exit,
+	.test_cases = printf_test_cases,
+};
+
+kunit_test_suite(printf_test_suite);
+
 MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>");
 MODULE_DESCRIPTION("Test cases for printf facility");
 MODULE_LICENSE("GPL");
diff --git a/tools/testing/selftests/lib/config b/tools/testing/selftests/lib/config
index 306a3d4dca98..f4b4b8822241 100644
--- a/tools/testing/selftests/lib/config
+++ b/tools/testing/selftests/lib/config
@@ -1,4 +1,3 @@
-CONFIG_TEST_PRINTF=m
 CONFIG_TEST_SCANF=m
 CONFIG_TEST_BITMAP=m
 CONFIG_TEST_BITOPS=m
diff --git a/tools/testing/selftests/lib/printf.sh b/tools/testing/selftests/lib/printf.sh
deleted file mode 100755
index 05f4544e87f9..000000000000
--- a/tools/testing/selftests/lib/printf.sh
+++ /dev/null
@@ -1,4 +0,0 @@
-#!/bin/sh
-# SPDX-License-Identifier: GPL-2.0
-# Tests the printf infrastructure using test_printf kernel module.
-$(dirname $0)/../kselftest/module.sh "printf" test_printf

-- 
2.48.1

[PATCH v4 2/3] printf: break kunit into test cases

[Tamir Duberstein]

Move all tests into `printf_test_cases`. This gives us nicer output in
the event of a failure.

Combine `plain_format` and `plain_hash` into `hash_pointer` since
they're testing the same scenario.

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
 lib/tests/printf_kunit.c | 331 +++++++++++++++++------------------------------
 1 file changed, 121 insertions(+), 210 deletions(-)

diff --git a/lib/tests/printf_kunit.c b/lib/tests/printf_kunit.c
index 287bbfb61148..013df6f6dd49 100644
--- a/lib/tests/printf_kunit.c
+++ b/lib/tests/printf_kunit.c
@@ -38,13 +38,8 @@ static unsigned int total_tests;
 static char *test_buffer;
 static char *alloced_buffer;
 
-static struct kunit *kunittest;
-
-#define tc_fail(fmt, ...) \
-	KUNIT_FAIL(kunittest, fmt, ##__VA_ARGS__)
-
-static void __printf(4, 0)
-do_test(int bufsize, const char *expect, int elen,
+static void __printf(5, 0)
+do_test(struct kunit *kunittest, int bufsize, const char *expect, int elen,
 	const char *fmt, va_list ap)
 {
 	va_list aq;
@@ -58,59 +53,64 @@ do_test(int bufsize, const char *expect, int elen,
 	va_end(aq);
 
 	if (ret != elen) {
-		tc_fail("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d",
-			bufsize, fmt, ret, elen);
+		KUNIT_FAIL(kunittest, "vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d",
+			   bufsize, fmt, ret, elen);
 		return;
 	}
 
 	if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) {
-		tc_fail("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer",
-			bufsize, fmt);
+		KUNIT_FAIL(kunittest, "vsnprintf(buf, %d, \"%s\", ...) wrote before buffer",
+			   bufsize, fmt);
 		return;
 	}
 
 	if (!bufsize) {
 		if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_SIZE)) {
-			tc_fail("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer", fmt);
+			KUNIT_FAIL(kunittest, "vsnprintf(buf, 0, \"%s\", ...) wrote to buffer",
+				   fmt);
 		}
 		return;
 	}
 
 	written = min(bufsize-1, elen);
 	if (test_buffer[written]) {
-		tc_fail("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer",
-			bufsize, fmt);
+		KUNIT_FAIL(kunittest,
+			   "vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer",
+			   bufsize, fmt);
 		return;
 	}
 
 	if (memchr_inv(test_buffer + written + 1, FILL_CHAR, bufsize - (written + 1))) {
-		tc_fail("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator",
-			bufsize, fmt);
+		KUNIT_FAIL(kunittest,
+			   "vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator",
+			   bufsize, fmt);
 		return;
 	}
 
 	if (memchr_inv(test_buffer + bufsize, FILL_CHAR, BUF_SIZE + PAD_SIZE - bufsize)) {
-		tc_fail("vsnprintf(buf, %d, \"%s\", ...) wrote beyond buffer", bufsize, fmt);
+		KUNIT_FAIL(kunittest, "vsnprintf(buf, %d, \"%s\", ...) wrote beyond buffer",
+			   bufsize, fmt);
 		return;
 	}
 
 	if (memcmp(test_buffer, expect, written)) {
-		tc_fail("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'",
-			bufsize, fmt, test_buffer, written, expect);
+		KUNIT_FAIL(kunittest, "vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'",
+			   bufsize, fmt, test_buffer, written, expect);
 		return;
 	}
 }
 
-static void __printf(3, 4)
-__test(const char *expect, int elen, const char *fmt, ...)
+static void __printf(4, 0)
+__test(struct kunit *kunittest, const char *expect, int elen, const char *fmt, ...)
 {
 	va_list ap;
 	int rand;
 	char *p;
 
 	if (elen >= BUF_SIZE) {
-		tc_fail("error in test suite: expected output length %d too long. Format was '%s'.",
-			elen, fmt);
+		KUNIT_FAIL(kunittest,
+			   "error in test suite: expected length (%d) >= BUF_SIZE (%d). fmt=\"%s\"",
+			   elen, BUF_SIZE, fmt);
 		return;
 	}
 
@@ -122,18 +122,19 @@ __test(const char *expect, int elen, const char *fmt, ...)
 	 * enough and 0), and then we also test that kvasprintf would
 	 * be able to print it as expected.
 	 */
-	do_test(BUF_SIZE, expect, elen, fmt, ap);
+	do_test(kunittest, BUF_SIZE, expect, elen, fmt, ap);
 	rand = get_random_u32_inclusive(1, elen + 1);
 	/* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */
-	do_test(rand, expect, elen, fmt, ap);
-	do_test(0, expect, elen, fmt, ap);
+	do_test(kunittest, rand, expect, elen, fmt, ap);
+	do_test(kunittest, 0, expect, elen, fmt, ap);
 
 	p = kvasprintf(GFP_KERNEL, fmt, ap);
 	if (p) {
 		total_tests++;
 		if (memcmp(p, expect, elen+1)) {
-			tc_fail("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'",
-				fmt, p, expect);
+			KUNIT_FAIL(kunittest,
+				   "kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'",
+				   fmt, p, expect);
 		}
 		kfree(p);
 	}
@@ -141,10 +142,10 @@ __test(const char *expect, int elen, const char *fmt, ...)
 }
 
 #define test(expect, fmt, ...)					\
-	__test(expect, strlen(expect), fmt, ##__VA_ARGS__)
+	__test(kunittest, expect, strlen(expect), fmt, ##__VA_ARGS__)
 
 static void
-test_basic(void)
+test_basic(struct kunit *kunittest)
 {
 	/* Work around annoying "warning: zero-length gnu_printf format string". */
 	char nul = '\0';
@@ -152,11 +153,11 @@ test_basic(void)
 	test("", &nul);
 	test("100%", "100%%");
 	test("xxx%yyy", "xxx%cyyy", '%');
-	__test("xxx\0yyy", 7, "xxx%cyyy", '\0');
+	__test(kunittest, "xxx\0yyy", 7, "xxx%cyyy", '\0');
 }
 
 static void
-test_number(void)
+test_number(struct kunit *kunittest)
 {
 	test("0x1234abcd  ", "%#-12x", 0x1234abcd);
 	test("  0x1234abcd", "%#12x", 0x1234abcd);
@@ -178,7 +179,7 @@ test_number(void)
 }
 
 static void
-test_string(void)
+test_string(struct kunit *kunittest)
 {
 	test("", "%s%.0s", "", "123");
 	test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456");
@@ -215,29 +216,6 @@ test_string(void)
 #define ZEROS "00000000"	/* hex 32 zero bits */
 #define ONES "ffffffff"		/* hex 32 one bits */
 
-static int
-plain_format(void)
-{
-	char buf[PLAIN_BUF_SIZE];
-	int nchars;
-
-	nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR);
-
-	if (nchars != PTR_WIDTH)
-		return -1;
-
-	if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) {
-		kunit_warn(kunittest, "crng possibly not yet initialized. plain 'p' buffer contains \"%s\"",
-			PTR_VAL_NO_CRNG);
-		return 0;
-	}
-
-	if (strncmp(buf, ZEROS, strlen(ZEROS)) != 0)
-		return -1;
-
-	return 0;
-}
-
 #else
 
 #define PTR_WIDTH 8
@@ -247,89 +225,44 @@ plain_format(void)
 #define ZEROS ""
 #define ONES ""
 
-static int
-plain_format(void)
-{
-	/* Format is implicitly tested for 32 bit machines by plain_hash() */
-	return 0;
-}
-
 #endif	/* BITS_PER_LONG == 64 */
 
-static int
-plain_hash_to_buffer(const void *p, char *buf, size_t len)
+static void
+plain_hash_to_buffer(struct kunit *kunittest, const void *p, char *buf, size_t len)
 {
-	int nchars;
-
-	nchars = snprintf(buf, len, "%p", p);
-
-	if (nchars != PTR_WIDTH)
-		return -1;
+	KUNIT_ASSERT_EQ(kunittest, snprintf(buf, len, "%p", p), PTR_WIDTH);
 
 	if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) {
 		kunit_warn(kunittest, "crng possibly not yet initialized. plain 'p' buffer contains \"%s\"",
 			PTR_VAL_NO_CRNG);
-		return 0;
 	}
-
-	return 0;
 }
 
-static int
-plain_hash(void)
-{
-	char buf[PLAIN_BUF_SIZE];
-	int ret;
-
-	ret = plain_hash_to_buffer(PTR, buf, PLAIN_BUF_SIZE);
-	if (ret)
-		return ret;
-
-	if (strncmp(buf, PTR_STR, PTR_WIDTH) == 0)
-		return -1;
-
-	return 0;
-}
-
-/*
- * We can't use test() to test %p because we don't know what output to expect
- * after an address is hashed.
- */
 static void
-plain(void)
+hash_pointer(struct kunit *kunittest)
 {
-	int err;
+	if (no_hash_pointers)
+		kunit_skip(kunittest, "hash pointers disabled");
 
-	if (no_hash_pointers) {
-		kunit_warn(kunittest, "skipping plain 'p' tests");
-		return;
-	}
+	char buf[PLAIN_BUF_SIZE];
 
-	err = plain_hash();
-	if (err) {
-		tc_fail("plain 'p' does not appear to be hashed");
-		return;
-	}
+	plain_hash_to_buffer(kunittest, PTR, buf, PLAIN_BUF_SIZE);
 
-	err = plain_format();
-	if (err) {
-		tc_fail("hashing plain 'p' has unexpected format");
-	}
+	/*
+	 * We can't use test() to test %p because we don't know what output to expect
+	 * after an address is hashed.
+	 */
+
+	KUNIT_EXPECT_MEMEQ(kunittest, buf, ZEROS, strlen(ZEROS));
+	KUNIT_EXPECT_MEMNEQ(kunittest, buf+strlen(ZEROS), PTR_STR, PTR_WIDTH);
 }
 
 static void
-test_hashed(const char *fmt, const void *p)
+test_hashed(struct kunit *kunittest, const char *fmt, const void *p)
 {
 	char buf[PLAIN_BUF_SIZE];
-	int ret;
 
-	/*
-	 * No need to increase failed test counter since this is assumed
-	 * to be called after plain().
-	 */
-	ret = plain_hash_to_buffer(p, buf, PLAIN_BUF_SIZE);
-	if (ret)
-		return;
+	plain_hash_to_buffer(kunittest, p, buf, PLAIN_BUF_SIZE);
 
 	test(buf, fmt, p);
 }
@@ -338,7 +271,7 @@ test_hashed(const char *fmt, const void *p)
  * NULL pointers aren't hashed.
  */
 static void
-null_pointer(void)
+null_pointer(struct kunit *kunittest)
 {
 	test(ZEROS "00000000", "%p", NULL);
 	test(ZEROS "00000000", "%px", NULL);
@@ -349,7 +282,7 @@ null_pointer(void)
  * Error pointers aren't hashed.
  */
 static void
-error_pointer(void)
+error_pointer(struct kunit *kunittest)
 {
 	test(ONES "fffffff5", "%p", ERR_PTR(-11));
 	test(ONES "fffffff5", "%px", ERR_PTR(-11));
@@ -359,26 +292,26 @@ error_pointer(void)
 #define PTR_INVALID ((void *)0x000000ab)
 
 static void
-invalid_pointer(void)
+invalid_pointer(struct kunit *kunittest)
 {
-	test_hashed("%p", PTR_INVALID);
+	test_hashed(kunittest, "%p", PTR_INVALID);
 	test(ZEROS "000000ab", "%px", PTR_INVALID);
 	test("(efault)", "%pE", PTR_INVALID);
 }
 
 static void
-symbol_ptr(void)
+symbol_ptr(struct kunit *kunittest)
 {
 }
 
 static void
-kernel_ptr(void)
+kernel_ptr(struct kunit *kunittest)
 {
 	/* We can't test this without access to kptr_restrict. */
 }
 
 static void
-struct_resource(void)
+struct_resource(struct kunit *kunittest)
 {
 	struct resource test_resource = {
 		.start = 0xc0ffee00,
@@ -427,7 +360,7 @@ struct_resource(void)
 }
 
 static void
-struct_range(void)
+struct_range(struct kunit *kunittest)
 {
 	struct range test_range = DEFINE_RANGE(0xc0ffee00ba5eba11,
 					       0xc0ffee00ba5eba11);
@@ -443,17 +376,17 @@ struct_range(void)
 }
 
 static void
-addr(void)
+addr(struct kunit *kunittest)
 {
 }
 
 static void
-escaped_str(void)
+escaped_str(struct kunit *kunittest)
 {
 }
 
 static void
-hex_string(void)
+hex_string(struct kunit *kunittest)
 {
 	const char buf[3] = {0xc0, 0xff, 0xee};
 
@@ -464,7 +397,7 @@ hex_string(void)
 }
 
 static void
-mac(void)
+mac(struct kunit *kunittest)
 {
 	const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05};
 
@@ -476,7 +409,7 @@ mac(void)
 }
 
 static void
-ip4(void)
+ip4(struct kunit *kunittest)
 {
 	struct sockaddr_in sa;
 
@@ -491,19 +424,12 @@ ip4(void)
 }
 
 static void
-ip6(void)
+ip6(struct kunit *kunittest)
 {
 }
 
 static void
-ip(void)
-{
-	ip4();
-	ip6();
-}
-
-static void
-uuid(void)
+uuid(struct kunit *kunittest)
 {
 	const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
 			       0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf};
@@ -530,7 +456,7 @@ static struct dentry test_dentry[4] = {
 };
 
 static void
-dentry(void)
+dentry(struct kunit *kunittest)
 {
 	test("foo", "%pd", &test_dentry[0]);
 	test("foo", "%pd2", &test_dentry[0]);
@@ -551,12 +477,12 @@ dentry(void)
 }
 
 static void
-struct_va_format(void)
+struct_va_format(struct kunit *kunittest)
 {
 }
 
 static void
-time_and_date(void)
+time_and_date(struct kunit *kunittest)
 {
 	/* 1543210543 */
 	const struct rtc_time tm = {
@@ -590,12 +516,12 @@ time_and_date(void)
 }
 
 static void
-struct_clk(void)
+struct_clk(struct kunit *kunittest)
 {
 }
 
 static void
-large_bitmap(void)
+large_bitmap(struct kunit *kunittest)
 {
 	const int nbits = 1 << 16;
 	unsigned long *bits = bitmap_zalloc(nbits, GFP_KERNEL);
@@ -609,7 +535,7 @@ large_bitmap(void)
 }
 
 static void
-bitmap(void)
+bitmap(struct kunit *kunittest)
 {
 	DECLARE_BITMAP(bits, 20);
 	const int primes[] = {2,3,5,7,11,13,17,19};
@@ -628,11 +554,11 @@ bitmap(void)
 	test("fffff|fffff", "%20pb|%*pb", bits, 20, bits);
 	test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits);
 
-	large_bitmap();
+	large_bitmap(kunittest);
 }
 
 static void
-netdev_features(void)
+netdev_features(struct kunit *kunittest)
 {
 }
 
@@ -658,8 +584,8 @@ static const struct page_flags_test pft[] = {
 };
 
 static void
-page_flags_test(int section, int node, int zone, int last_cpupid,
-		int kasan_tag, unsigned long flags, const char *name,
+page_flags_test(struct kunit *kunittest, int section, int node, int zone,
+		int last_cpupid, int kasan_tag, unsigned long flags, const char *name,
 		char *cmp_buf)
 {
 	unsigned long values[] = {section, node, zone, last_cpupid, kasan_tag};
@@ -696,25 +622,24 @@ page_flags_test(int section, int node, int zone, int last_cpupid,
 }
 
 static void
-flags(void)
+flags(struct kunit *kunittest)
 {
 	unsigned long flags;
 	char *cmp_buffer;
 	gfp_t gfp;
 
-	cmp_buffer = kmalloc(BUF_SIZE, GFP_KERNEL);
-	if (!cmp_buffer)
-		return;
+	cmp_buffer = kunit_kmalloc(kunittest, BUF_SIZE, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(kunittest, cmp_buffer);
 
 	flags = 0;
-	page_flags_test(0, 0, 0, 0, 0, flags, "", cmp_buffer);
+	page_flags_test(kunittest, 0, 0, 0, 0, 0, flags, "", cmp_buffer);
 
 	flags = 1UL << NR_PAGEFLAGS;
-	page_flags_test(0, 0, 0, 0, 0, flags, "", cmp_buffer);
+	page_flags_test(kunittest, 0, 0, 0, 0, 0, flags, "", cmp_buffer);
 
 	flags |= 1UL << PG_uptodate | 1UL << PG_dirty | 1UL << PG_lru
 		| 1UL << PG_active | 1UL << PG_swapbacked;
-	page_flags_test(1, 1, 1, 0x1fffff, 1, flags,
+	page_flags_test(kunittest, 1, 1, 1, 0x1fffff, 1, flags,
 			"uptodate|dirty|lru|active|swapbacked",
 			cmp_buffer);
 
@@ -739,11 +664,9 @@ flags(void)
 							(unsigned long) gfp);
 	gfp |= __GFP_HIGH;
 	test(cmp_buffer, "%pGg", &gfp);
-
-	kfree(cmp_buffer);
 }
 
-static void fwnode_pointer(void)
+static void fwnode_pointer(struct kunit *kunittest)
 {
 	const struct software_node first = { .name = "first" };
 	const struct software_node second = { .name = "second", .parent = &first };
@@ -757,8 +680,7 @@ static void fwnode_pointer(void)
 
 	rval = software_node_register_node_group(group);
 	if (rval) {
-		kunit_warn(kunittest, "cannot register softnodes; rval %d", rval);
-		return;
+		kunit_skip(kunittest, "cannot register softnodes; rval %d", rval);
 	}
 
 	test(full_name_second, "%pfw", software_node_fwnode(&second));
@@ -770,7 +692,7 @@ static void fwnode_pointer(void)
 	software_node_unregister_node_group(group);
 }
 
-static void fourcc_pointer(void)
+static void fourcc_pointer(struct kunit *kunittest)
 {
 	struct {
 		u32 code;
@@ -788,13 +710,13 @@ static void fourcc_pointer(void)
 }
 
 static void
-errptr(void)
+errptr(struct kunit *kunittest)
 {
 	test("-1234", "%pe", ERR_PTR(-1234));
 
 	/* Check that %pe with a non-ERR_PTR gets treated as ordinary %p. */
 	BUILD_BUG_ON(IS_ERR(PTR));
-	test_hashed("%pe", PTR);
+	test_hashed(kunittest, "%pe", PTR);
 
 #ifdef CONFIG_SYMBOLIC_ERRNAME
 	test("(-ENOTSOCK)", "(%pe)", ERR_PTR(-ENOTSOCK));
@@ -807,65 +729,54 @@ errptr(void)
 #endif
 }
 
-static void
-test_pointer(void)
-{
-	plain();
-	null_pointer();
-	error_pointer();
-	invalid_pointer();
-	symbol_ptr();
-	kernel_ptr();
-	struct_resource();
-	struct_range();
-	addr();
-	escaped_str();
-	hex_string();
-	mac();
-	ip();
-	uuid();
-	dentry();
-	struct_va_format();
-	time_and_date();
-	struct_clk();
-	bitmap();
-	netdev_features();
-	flags();
-	errptr();
-	fwnode_pointer();
-	fourcc_pointer();
-}
-
-static void printf_test(struct kunit *test)
+static int printf_suite_init(struct kunit_suite *suite)
 {
+	total_tests = 0;
+
 	alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL);
 	if (!alloced_buffer)
-		return;
+		return -ENOMEM;
 	test_buffer = alloced_buffer + PAD_SIZE;
 
-	kunittest = test;
-
-	test_basic();
-	test_number();
-	test_string();
-	test_pointer();
-
-	kfree(alloced_buffer);
-}
-
-static int printf_suite_init(struct kunit_suite *suite)
-{
-	total_tests = 0;
 	return 0;
 }
 
 static void printf_suite_exit(struct kunit_suite *suite)
 {
+	kfree(alloced_buffer);
+
 	kunit_info(suite, "ran %u tests", total_tests);
 }
 
 static struct kunit_case printf_test_cases[] = {
-	KUNIT_CASE(printf_test),
+	KUNIT_CASE(test_basic),
+	KUNIT_CASE(test_number),
+	KUNIT_CASE(test_string),
+	KUNIT_CASE(hash_pointer),
+	KUNIT_CASE(null_pointer),
+	KUNIT_CASE(error_pointer),
+	KUNIT_CASE(invalid_pointer),
+	KUNIT_CASE(symbol_ptr),
+	KUNIT_CASE(kernel_ptr),
+	KUNIT_CASE(struct_resource),
+	KUNIT_CASE(struct_range),
+	KUNIT_CASE(addr),
+	KUNIT_CASE(escaped_str),
+	KUNIT_CASE(hex_string),
+	KUNIT_CASE(mac),
+	KUNIT_CASE(ip4),
+	KUNIT_CASE(ip6),
+	KUNIT_CASE(uuid),
+	KUNIT_CASE(dentry),
+	KUNIT_CASE(struct_va_format),
+	KUNIT_CASE(time_and_date),
+	KUNIT_CASE(struct_clk),
+	KUNIT_CASE(bitmap),
+	KUNIT_CASE(netdev_features),
+	KUNIT_CASE(flags),
+	KUNIT_CASE(errptr),
+	KUNIT_CASE(fwnode_pointer),
+	KUNIT_CASE(fourcc_pointer),
 	{}
 };
 

-- 
2.48.1

[PATCH v4 3/3] printf: implicate test line in failure messages

[Tamir Duberstein]

This improves the failure output by pointing to the failing line at the
top level of the test, e.g.:
      # test_number: EXPECTATION FAILED at lib/printf_kunit.c:103
  lib/printf_kunit.c:167: vsnprintf(buf, 256, "%#-12x", ...) wrote '0x1234abcd  ', expected '0x1234abce  '
      # test_number: EXPECTATION FAILED at lib/printf_kunit.c:142
  lib/printf_kunit.c:167: kvasprintf(..., "%#-12x", ...) returned '0x1234abcd  ', expected '0x1234abce  '

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
 lib/tests/printf_kunit.c | 60 ++++++++++++++++++++++++++----------------------
 1 file changed, 33 insertions(+), 27 deletions(-)

diff --git a/lib/tests/printf_kunit.c b/lib/tests/printf_kunit.c
index 013df6f6dd49..aa5011156788 100644
--- a/lib/tests/printf_kunit.c
+++ b/lib/tests/printf_kunit.c
@@ -39,8 +39,8 @@ static char *test_buffer;
 static char *alloced_buffer;
 
 static void __printf(5, 0)
-do_test(struct kunit *kunittest, int bufsize, const char *expect, int elen,
-	const char *fmt, va_list ap)
+do_test(struct kunit *kunittest, const char *file, const int line, int bufsize, const char *expect,
+	int elen, const char *fmt, va_list ap)
 {
 	va_list aq;
 	int ret, written;
@@ -53,21 +53,24 @@ do_test(struct kunit *kunittest, int bufsize, const char *expect, int elen,
 	va_end(aq);
 
 	if (ret != elen) {
-		KUNIT_FAIL(kunittest, "vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d",
-			   bufsize, fmt, ret, elen);
+		KUNIT_FAIL(kunittest,
+			   "%s:%d: vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d",
+			   file, line, bufsize, fmt, ret, elen);
 		return;
 	}
 
 	if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) {
-		KUNIT_FAIL(kunittest, "vsnprintf(buf, %d, \"%s\", ...) wrote before buffer",
-			   bufsize, fmt);
+		KUNIT_FAIL(kunittest,
+			   "%s:%d: vsnprintf(buf, %d, \"%s\", ...) wrote before buffer",
+			   file, line, bufsize, fmt);
 		return;
 	}
 
 	if (!bufsize) {
 		if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_SIZE)) {
-			KUNIT_FAIL(kunittest, "vsnprintf(buf, 0, \"%s\", ...) wrote to buffer",
-				   fmt);
+			KUNIT_FAIL(kunittest,
+				   "%s:%d: vsnprintf(buf, 0, \"%s\", ...) wrote to buffer",
+				   file, line, fmt);
 		}
 		return;
 	}
@@ -75,33 +78,36 @@ do_test(struct kunit *kunittest, int bufsize, const char *expect, int elen,
 	written = min(bufsize-1, elen);
 	if (test_buffer[written]) {
 		KUNIT_FAIL(kunittest,
-			   "vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer",
-			   bufsize, fmt);
+			   "%s:%d: vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer",
+			   file, line, bufsize, fmt);
 		return;
 	}
 
 	if (memchr_inv(test_buffer + written + 1, FILL_CHAR, bufsize - (written + 1))) {
 		KUNIT_FAIL(kunittest,
-			   "vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator",
-			   bufsize, fmt);
+			   "%s:%d: vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator",
+			   file, line, bufsize, fmt);
 		return;
 	}
 
 	if (memchr_inv(test_buffer + bufsize, FILL_CHAR, BUF_SIZE + PAD_SIZE - bufsize)) {
-		KUNIT_FAIL(kunittest, "vsnprintf(buf, %d, \"%s\", ...) wrote beyond buffer",
-			   bufsize, fmt);
+		KUNIT_FAIL(kunittest,
+			   "%s:%d: vsnprintf(buf, %d, \"%s\", ...) wrote beyond buffer",
+			   file, line, bufsize, fmt);
 		return;
 	}
 
 	if (memcmp(test_buffer, expect, written)) {
-		KUNIT_FAIL(kunittest, "vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'",
-			   bufsize, fmt, test_buffer, written, expect);
+		KUNIT_FAIL(kunittest,
+			   "%s:%d: vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'",
+			   file, line, bufsize, fmt, test_buffer, written, expect);
 		return;
 	}
 }
 
-static void __printf(4, 0)
-__test(struct kunit *kunittest, const char *expect, int elen, const char *fmt, ...)
+static void __printf(6, 0)
+__test(struct kunit *kunittest, const char *file, const int line, const char *expect, int elen,
+	const char *fmt, ...)
 {
 	va_list ap;
 	int rand;
@@ -109,8 +115,8 @@ __test(struct kunit *kunittest, const char *expect, int elen, const char *fmt, .
 
 	if (elen >= BUF_SIZE) {
 		KUNIT_FAIL(kunittest,
-			   "error in test suite: expected length (%d) >= BUF_SIZE (%d). fmt=\"%s\"",
-			   elen, BUF_SIZE, fmt);
+			   "%s:%d: error in test suite: expected length (%d) >= BUF_SIZE (%d). fmt=\"%s\"",
+			   file, line, elen, BUF_SIZE, fmt);
 		return;
 	}
 
@@ -122,19 +128,19 @@ __test(struct kunit *kunittest, const char *expect, int elen, const char *fmt, .
 	 * enough and 0), and then we also test that kvasprintf would
 	 * be able to print it as expected.
 	 */
-	do_test(kunittest, BUF_SIZE, expect, elen, fmt, ap);
+	do_test(kunittest, file, line, BUF_SIZE, expect, elen, fmt, ap);
 	rand = get_random_u32_inclusive(1, elen + 1);
 	/* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */
-	do_test(kunittest, rand, expect, elen, fmt, ap);
-	do_test(kunittest, 0, expect, elen, fmt, ap);
+	do_test(kunittest, file, line, rand, expect, elen, fmt, ap);
+	do_test(kunittest, file, line, 0, expect, elen, fmt, ap);
 
 	p = kvasprintf(GFP_KERNEL, fmt, ap);
 	if (p) {
 		total_tests++;
 		if (memcmp(p, expect, elen+1)) {
 			KUNIT_FAIL(kunittest,
-				   "kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'",
-				   fmt, p, expect);
+				   "%s:%d: kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'",
+				   file, line, fmt, p, expect);
 		}
 		kfree(p);
 	}
@@ -142,7 +148,7 @@ __test(struct kunit *kunittest, const char *expect, int elen, const char *fmt, .
 }
 
 #define test(expect, fmt, ...)					\
-	__test(kunittest, expect, strlen(expect), fmt, ##__VA_ARGS__)
+	__test(kunittest, __FILE__, __LINE__, expect, strlen(expect), fmt, ##__VA_ARGS__)
 
 static void
 test_basic(struct kunit *kunittest)
@@ -153,7 +159,7 @@ test_basic(struct kunit *kunittest)
 	test("", &nul);
 	test("100%", "100%%");
 	test("xxx%yyy", "xxx%cyyy", '%');
-	__test(kunittest, "xxx\0yyy", 7, "xxx%cyyy", '\0');
+	__test(kunittest, __FILE__, __LINE__, "xxx\0yyy", 7, "xxx%cyyy", '\0');
 }
 
 static void

-- 
2.48.1

Re: [PATCH v4 3/3] printf: implicate test line in failure messages

[Rasmus Villemoes]

On Fri, 14 Feb 2025 at 22:53, Tamir Duberstein <tamird@gmail.com> wrote:
>
> This improves the failure output by pointing to the failing line at the
> top level of the test, e.g.:
>       # test_number: EXPECTATION FAILED at lib/printf_kunit.c:103
>   lib/printf_kunit.c:167: vsnprintf(buf, 256, "%#-12x", ...) wrote '0x1234abcd  ', expected '0x1234abce  '
>       # test_number: EXPECTATION FAILED at lib/printf_kunit.c:142
>   lib/printf_kunit.c:167: kvasprintf(..., "%#-12x", ...) returned '0x1234abcd  ', expected '0x1234abce  '
>

Actually, I'm not sure that is an improvement as-is, with the two
different line numbers being printed. It takes some thought to
recognize which one is relevant and which one is not.

Can't we have a variant of KUNIT_FAIL that allows one to pass the
file/line info when the caller has better info than the location of
the KUNIT_FAIL itself?

>  static void __printf(5, 0)
> -do_test(struct kunit *kunittest, int bufsize, const char *expect, int elen,
> -       const char *fmt, va_list ap)
> +do_test(struct kunit *kunittest, const char *file, const int line, int bufsize, const char *expect,
> +       int elen, const char *fmt, va_list ap)

This can't be right, the __printf attribute must be updated accordingly.

Rasmus

Re: [PATCH v4 3/3] printf: implicate test line in failure messages

[Tamir Duberstein]

On Wed, Feb 19, 2025 at 3:41 PM Rasmus Villemoes
<linux@rasmusvillemoes.dk> wrote:
>
> On Fri, 14 Feb 2025 at 22:53, Tamir Duberstein <tamird@gmail.com> wrote:
> >
> > This improves the failure output by pointing to the failing line at the
> > top level of the test, e.g.:
> >       # test_number: EXPECTATION FAILED at lib/printf_kunit.c:103
> >   lib/printf_kunit.c:167: vsnprintf(buf, 256, "%#-12x", ...) wrote '0x1234abcd  ', expected '0x1234abce  '
> >       # test_number: EXPECTATION FAILED at lib/printf_kunit.c:142
> >   lib/printf_kunit.c:167: kvasprintf(..., "%#-12x", ...) returned '0x1234abcd  ', expected '0x1234abce  '
> >
>
> Actually, I'm not sure that is an improvement as-is, with the two
> different line numbers being printed. It takes some thought to
> recognize which one is relevant and which one is not.

They're both relevant -- `do_test` does a bunch of checks, so you want
to know which particular check failed, but also which invocation at
the top level resulted in that check failing.

> Can't we have a variant of KUNIT_FAIL that allows one to pass the
> file/line info when the caller has better info than the location of
> the KUNIT_FAIL itself?
>
> >  static void __printf(5, 0)
> > -do_test(struct kunit *kunittest, int bufsize, const char *expect, int elen,
> > -       const char *fmt, va_list ap)
> > +do_test(struct kunit *kunittest, const char *file, const int line, int bufsize, const char *expect,
> > +       int elen, const char *fmt, va_list ap)
>
> This can't be right, the __printf attribute must be updated accordingly.

Good catch. Oddly I'm not able to reproduce any compiler complaints
here, even with the attribute completely removed.