[Linux-kernel-mentees] [PATCH v2] lib: Convert test_printf.c to KUnit

[Petr Mladek]

On Thu 2020-10-22 20:43:49, Arpitha Raghunandan wrote:
> Convert test lib/test_printf.c to KUnit. More information about

> Converted test success:
>     # Subtest: printf-kunit-test
>     1..1
>     ok 1 - selftest
> ok 1 - printf-kunit-test
> 
> Converted test failure:
>     # Subtest: printf-kunit-test
>     1..1
>     # selftest: EXPECTATION FAILED at lib/printf_kunit.c:82
> vsnprintf(buf, 256, "%pi4|%pI4", ...) wrote
> '127.000.000.001|127.0.0.1', expected '127-000.000.001|127.0.0.1'
>     # selftest: EXPECTATION FAILED at lib/printf_kunit.c:82
> vsnprintf(buf, 5, "%pi4|%pI4", ...) wrote '127.', expected '127-'
>     # selftest: EXPECTATION FAILED at lib/printf_kunit.c:118
> kvasprintf(..., "%pi4|%pI4", ...) returned
> '127.000.000.001|127.0.0.1', expected '127-000.000.001|127.0.0.1'
>     not ok 1 - selftest

I agree with others that there should be more KUNIT_CASEs.

> not ok 1 - printf-kunit-test

> --- a/lib/test_printf.c
> +++ b/lib/printf_kunit.c

There is no standard at the moment. I see struct kunit_source defined,
for example, in the following files:

*test*.c:

      drivers/base/power/qos-test.c:
      drivers/base/test/property-entry-test.c:
      drivers/thunderbolt/test.c:
      fs/ext4/inode-test.c:
      kernel/kcsan/kcsan-test.c:
      kernel/sysctl-test.c:
      lib/kunit/string-stream-test.c:
      lib/list-test.c:
      lib/test_bits.c:
      lib/test_kasan.c:
      lib/test_linear_ranges.c:
      net/mptcp/crypto_test.c:
      net/mptcp/token_test.c:
      security/apparmor/policy_unpack_test.c:

kunit-*-test.c:

       lib/kunit/kunit-example-test.c:
       lib/kunit/kunit-test.c:

*_kunit.c

      lib/bitfield_kunit.c:

Please, either unify names of all the above modules or keep test_printf.c



> @@ -5,6 +5,7 @@
>  
>  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>  
> +#include <kunit/test.h>
>  #include <linux/init.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
> @@ -30,64 +31,57 @@
>  #define PAD_SIZE 16
>  #define FILL_CHAR '$'
>  
> -static unsigned total_tests __initdata;
> -static unsigned failed_tests __initdata;
>  static char *test_buffer __initdata;
>  static char *alloced_buffer __initdata;
> +struct kunit *kunittest;

This should be static variable.

>  
> -static int __printf(4, 0) __init
> +static void __printf(4, 0) __init
>  do_test(int bufsize, const char *expect, int elen,
>  	const char *fmt, va_list ap)
>  {
>  	va_list aq;
>  	int ret, written;
>  

> @@ -696,8 +684,9 @@ test_pointer(void)
>  	fwnode_pointer();
>  }
>  
> -static void __init selftest(void)
> +static void __init selftest(struct kunit *ktest)

>  {
> +	kunittest = ktest;
>  	alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL);

The allocation and freeing should be done by the init,exit
callbacs in struct kunit_testsuite. For example, see
lib/kunit/kunit-test.c

This function can then be removed. The particular tests will
be called via more KUNIT_CASE() entries.

>  	if (!alloced_buffer)
>  		return;
> @@ -711,6 +700,17 @@ static void __init selftest(void)
>  	kfree(alloced_buffer);
>  }
>  
> -KSTM_MODULE_LOADERS(test_printf);
> +static struct kunit_case printf_test_cases[] = {
> +	KUNIT_CASE(selftest),
> +	{}
> +};
> +
> +static struct kunit_suite printf_test_suite = {
> +	.name = "printf-kunit-test",

Please, use:

	.name = "printf"

The fact that it is kunit-test should be clear from the context.

> +	.test_cases = printf_test_cases,
> +};
> +
> +kunit_test_suite(printf_test_suite);
> +

Best Regards,
Petr