Re: [PATCH v3] lib: Convert test_printf.c to KUnit

[Andy Shevchenko]

On Tue, Nov 03, 2020 at 04:40:49PM +0530, Arpitha Raghunandan wrote:
> Convert test lib/test_printf.c to KUnit. More information about
> KUnit can be found at:
> https://www.kernel.org/doc/html/latest/dev-tools/kunit/index.html.
> KUnit provides a common framework for unit tests in the kernel.
> KUnit and kselftest are standardizing around KTAP, converting this
> test to KUnit makes this test output in KTAP which we are trying to
> make the standard test result format for the kernel. More about
> the KTAP format can be found at:
> https://lore.kernel.org/linux-kselftest/CY4PR13MB1175B804E31E502221BC8163FD830@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/.
> I ran both the original and converted tests as is to produce the
> output for success of the test in the two cases. I also ran these
> tests with a small modification to show the difference in the output
> for failure of the test in both cases. The modification I made is:
> - test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr);
> + test("127-000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr);
> 
> Original test success:
> [    0.540860] test_printf: loaded.
> [    0.540863] test_printf: random seed = 0x5c46c33837bc0619
> [    0.541022] test_printf: all 388 tests passed
> 
> Original test failure:
> [    0.537980] test_printf: loaded.
> [    0.537983] test_printf: random seed = 0x1bc1efd881954afb
> [    0.538029] test_printf: vsnprintf(buf, 256, "%pi4|%pI4", ...) wrote '127.000.000.001|127.0.0.1', expected '127-000.000.001|127.0.0.1'
> [    0.538030] test_printf: kvasprintf(..., "%pi4|%pI4", ...) returned '127.000.000.001|127.0.0.1', expected '127-000.000.001|127.0.0.1'
> [    0.538124] test_printf: failed 2 out of 388 tests
> [    0.538125] test_printf: random seed used was 0x1bc1efd881954afb
> 
> Converted test success:
>     # Subtest: printf
>     1..25
>     ok 1 - test_basic
>     ok 2 - test_number
>     ok 3 - test_string
>     ok 4 - plain
>     ok 5 - null_pointer
>     ok 6 - error_pointer
>     ok 7 - invalid_pointer
>     ok 8 - symbol_ptr
>     ok 9 - kernel_ptr
>     ok 10 - struct_resource
>     ok 11 - addr
>     ok 12 - escaped_str
>     ok 13 - hex_string
>     ok 14 - mac
>     ok 15 - ip
>     ok 16 - uuid
>     ok 17 - dentry
>     ok 18 - struct_va_format
>     ok 19 - time_and_date
>     ok 20 - struct_clk
>     ok 21 - bitmap
>     ok 22 - netdev_features
>     ok 23 - flags
>     ok 24 - errptr
>     ok 25 - fwnode_pointer
> ok 1 - printf
> 
> Converted test failure:
>     # Subtest: printf
>     1..25
>     ok 1 - test_basic
>     ok 2 - test_number
>     ok 3 - test_string
>     ok 4 - plain
>     ok 5 - null_pointer
>     ok 6 - error_pointer
>     ok 7 - invalid_pointer
>     ok 8 - symbol_ptr
>     ok 9 - kernel_ptr
>     ok 10 - struct_resource
>     ok 11 - addr
>     ok 12 - escaped_str
>     ok 13 - hex_string
>     ok 14 - mac
>     # ip: 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'
>     # ip: EXPECTATION FAILED at lib/printf_kunit.c:124
> kvasprintf(..., "%pi4|%pI4", ...) returned '127.000.000.001|127.0.0.1', expected '127-000.000.001|127.0.0.1'
>     not ok 15 - ip
>     ok 16 - uuid
>     ok 17 - dentry
>     ok 18 - struct_va_format
>     ok 19 - time_and_date
>     ok 20 - struct_clk
>     ok 21 - bitmap
>     ok 22 - netdev_features
>     ok 23 - flags
>     ok 24 - errptr
>     ok 25 - fwnode_pointer
> not ok 1 - printf

Better, indeed.

But can be this improved to have a cumulative statistics, like showing only
number of total, succeeded, failed with details of the latter ones?

> This patch is based on top of Andy's series that renames KUnit based
> tests in lib/ and Ramsus' series on deterministic random testing.

For the reference:
https://lore.kernel.org/linux-kselftest/20201016110836.52613-1-andriy.shevchenko@xxxxxxxxxxxxxxx/

...

> -static void __init
> -test_string(void)
> +static void
> +test_string(struct kunit *ktest)

I guess no need anymore to keep them on two lines, just combine to one line.

-- 
With Best Regards,
Andy Shevchenko