* Re: [PATCH v2 2/2] lib/math/rational: Add Kunit test cases
2021-05-25 14:42 ` [PATCH v2 2/2] lib/math/rational: Add Kunit test cases Trent Piepho
@ 2021-05-25 16:00 ` Andy Shevchenko
2021-05-25 17:34 ` Daniel Latypov
2021-05-25 21:49 ` Andrew Morton
2 siblings, 0 replies; 10+ messages in thread
From: Andy Shevchenko @ 2021-05-25 16:00 UTC (permalink / raw)
To: Trent Piepho; +Cc: linux-kernel, andy, akpm, oskar, Daniel Latypov
On Tue, May 25, 2021 at 07:42:50AM -0700, Trent Piepho wrote:
> Adds a number of test cases that cover a range of possible code paths.
Good for the starter!
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Trent Piepho <tpiepho@gmail.com>
> ---
> lib/Kconfig.debug | 12 +++++++++
> lib/math/Makefile | 1 +
> lib/math/rational-test.c | 56 ++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 69 insertions(+)
> create mode 100644 lib/math/rational-test.c
>
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 678c13967580..6c0e66a7d416 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2429,6 +2429,18 @@ config BITS_TEST
>
> If unsure, say N.
>
> +config RATIONAL_KUNIT_TEST
> + tristate "KUnit test for rational.c" if !KUNIT_ALL_TESTS
> + depends on KUNIT
> + select RATIONAL
> + default KUNIT_ALL_TESTS
> + help
> + This builds the rational math unit test.
> + 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 TEST_UDELAY
> tristate "udelay test driver"
> help
> diff --git a/lib/math/Makefile b/lib/math/Makefile
> index 7456edb864fc..bfac26ddfc22 100644
> --- a/lib/math/Makefile
> +++ b/lib/math/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_PRIME_NUMBERS) += prime_numbers.o
> obj-$(CONFIG_RATIONAL) += rational.o
>
> obj-$(CONFIG_TEST_DIV64) += test_div64.o
> +obj-$(CONFIG_RATIONAL_KUNIT_TEST) += rational-test.o
> diff --git a/lib/math/rational-test.c b/lib/math/rational-test.c
> new file mode 100644
> index 000000000000..f64166dbe9ea
> --- /dev/null
> +++ b/lib/math/rational-test.c
> @@ -0,0 +1,56 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <kunit/test.h>
> +
> +#include <linux/rational.h>
> +
> +struct rational_test_param {
> + unsigned long num, den;
> + unsigned long max_num, max_den;
> + unsigned long exp_num, exp_den;
> +
> + const char *name;
> +};
> +
> +static const struct rational_test_param test_parameters[] = {
> + { 1230, 10, 100, 20, 100, 1, "Exceeds bounds, semi-convergent term > ½ last term" },
> + { 34567,100, 120, 20, 120, 1, "Exceeds bounds, semi-convergent term < ½ last term" },
> + { 1, 30, 100, 10, 0, 1, "Closest to zero" },
> + { 1, 19, 100, 10, 1, 10, "Closest to smallest non-zero" },
> + { 27,32, 16, 16, 11, 13, "Use convergent" },
> + { 1155, 7735, 255, 255, 33, 221, "Exact answer" },
> + { 87, 32, 70, 32, 68, 25, "Semiconvergent, numerator limit" },
> + { 14533, 4626, 15000, 2400, 7433, 2366, "Semiconvergent, demominator limit" },
> +};
> +
> +static void get_desc(const struct rational_test_param *param, char *desc)
> +{
> + strscpy(desc, param->name, KUNIT_PARAM_DESC_SIZE);
> +}
> +
> +/* Creates function rational_gen_params */
> +KUNIT_ARRAY_PARAM(rational, test_parameters, get_desc);
> +
> +static void rational_test(struct kunit *test)
> +{
> + const struct rational_test_param *param = (const struct rational_test_param *)test->param_value;
> + unsigned long n = 0, d = 0;
> +
> + rational_best_approximation(param->num, param->den, param->max_num, param->max_den, &n, &d);
> + KUNIT_EXPECT_EQ(test, n, param->exp_num);
> + KUNIT_EXPECT_EQ(test, d, param->exp_den);
> +}
> +
> +static struct kunit_case rational_test_cases[] = {
> + KUNIT_CASE_PARAM(rational_test, rational_gen_params),
> + {}
> +};
> +
> +static struct kunit_suite rational_test_suite = {
> + .name = "rational",
> + .test_cases = rational_test_cases,
> +};
> +
> +kunit_test_suites(&rational_test_suite);
> +
> +MODULE_LICENSE("GPL v2");
> --
> 2.26.2
>
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2 2/2] lib/math/rational: Add Kunit test cases
2021-05-25 14:42 ` [PATCH v2 2/2] lib/math/rational: Add Kunit test cases Trent Piepho
2021-05-25 16:00 ` Andy Shevchenko
@ 2021-05-25 17:34 ` Daniel Latypov
2021-05-25 21:09 ` Trent Piepho
2021-05-25 21:49 ` Andrew Morton
2 siblings, 1 reply; 10+ messages in thread
From: Daniel Latypov @ 2021-05-25 17:34 UTC (permalink / raw)
To: Trent Piepho
Cc: Linux Kernel Mailing List, andy, Andrew Morton, Oskar Schirmer
On Tue, May 25, 2021 at 7:43 AM Trent Piepho <tpiepho@gmail.com> wrote:
>
> Adds a number of test cases that cover a range of possible code paths.
>
> Signed-off-by: Trent Piepho <tpiepho@gmail.com>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Looks really good to me, just two nits.
Tangent:
I didn't check to see that this covers all the interesting cases, but
it seems like it does.
If you want, you can try generating a code coverage report to double check.
Instructions for doing so can be found in
https://lore.kernel.org/linux-kselftest/20210414222256.1280532-1-dlatypov@google.com/
I would have done that and included the #s in this email, but my
workplace decided to subtly break my workstation in some way and I
haven't gotten around to root causing...
> ---
> lib/Kconfig.debug | 12 +++++++++
> lib/math/Makefile | 1 +
> lib/math/rational-test.c | 56 ++++++++++++++++++++++++++++++++++++++++
Ah, sorry, I forgot to mention this in the previous email.
If you look at kunit/style.rst docs, you'll see the documentation now
states a preference for the name of this file to be one of
{rational_test.c, rational_kunit.c}
Unfortunately, we have a number of tests throughout the tree that
don't reflect this, including lib/kunit/kunit-example-test.c :(
> 3 files changed, 69 insertions(+)
> create mode 100644 lib/math/rational-test.c
>
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 678c13967580..6c0e66a7d416 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2429,6 +2429,18 @@ config BITS_TEST
>
> If unsure, say N.
>
> +config RATIONAL_KUNIT_TEST
> + tristate "KUnit test for rational.c" if !KUNIT_ALL_TESTS
> + depends on KUNIT
> + select RATIONAL
> + default KUNIT_ALL_TESTS
> + help
> + This builds the rational math unit test.
> + 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 TEST_UDELAY
> tristate "udelay test driver"
> help
> diff --git a/lib/math/Makefile b/lib/math/Makefile
> index 7456edb864fc..bfac26ddfc22 100644
> --- a/lib/math/Makefile
> +++ b/lib/math/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_PRIME_NUMBERS) += prime_numbers.o
> obj-$(CONFIG_RATIONAL) += rational.o
>
> obj-$(CONFIG_TEST_DIV64) += test_div64.o
> +obj-$(CONFIG_RATIONAL_KUNIT_TEST) += rational-test.o
> diff --git a/lib/math/rational-test.c b/lib/math/rational-test.c
> new file mode 100644
> index 000000000000..f64166dbe9ea
> --- /dev/null
> +++ b/lib/math/rational-test.c
> @@ -0,0 +1,56 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <kunit/test.h>
> +
> +#include <linux/rational.h>
> +
> +struct rational_test_param {
> + unsigned long num, den;
> + unsigned long max_num, max_den;
> + unsigned long exp_num, exp_den;
> +
> + const char *name;
> +};
> +
> +static const struct rational_test_param test_parameters[] = {
> + { 1230, 10, 100, 20, 100, 1, "Exceeds bounds, semi-convergent term > ½ last term" },
> + { 34567,100, 120, 20, 120, 1, "Exceeds bounds, semi-convergent term < ½ last term" },
very minor nit: there's an extraneous space character after the "100,"
> + { 1, 30, 100, 10, 0, 1, "Closest to zero" },
> + { 1, 19, 100, 10, 1, 10, "Closest to smallest non-zero" },
> + { 27,32, 16, 16, 11, 13, "Use convergent" },
> + { 1155, 7735, 255, 255, 33, 221, "Exact answer" },
> + { 87, 32, 70, 32, 68, 25, "Semiconvergent, numerator limit" },
> + { 14533, 4626, 15000, 2400, 7433, 2366, "Semiconvergent, demominator limit" },
> +};
> +
> +static void get_desc(const struct rational_test_param *param, char *desc)
> +{
> + strscpy(desc, param->name, KUNIT_PARAM_DESC_SIZE);
> +}
> +
> +/* Creates function rational_gen_params */
> +KUNIT_ARRAY_PARAM(rational, test_parameters, get_desc);
> +
> +static void rational_test(struct kunit *test)
> +{
> + const struct rational_test_param *param = (const struct rational_test_param *)test->param_value;
> + unsigned long n = 0, d = 0;
> +
> + rational_best_approximation(param->num, param->den, param->max_num, param->max_den, &n, &d);
> + KUNIT_EXPECT_EQ(test, n, param->exp_num);
> + KUNIT_EXPECT_EQ(test, d, param->exp_den);
> +}
> +
> +static struct kunit_case rational_test_cases[] = {
> + KUNIT_CASE_PARAM(rational_test, rational_gen_params),
> + {}
> +};
> +
> +static struct kunit_suite rational_test_suite = {
> + .name = "rational",
> + .test_cases = rational_test_cases,
> +};
> +
> +kunit_test_suites(&rational_test_suite);
> +
> +MODULE_LICENSE("GPL v2");
> --
> 2.26.2
>
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2 2/2] lib/math/rational: Add Kunit test cases
2021-05-25 17:34 ` Daniel Latypov
@ 2021-05-25 21:09 ` Trent Piepho
2021-05-25 22:03 ` Daniel Latypov
0 siblings, 1 reply; 10+ messages in thread
From: Trent Piepho @ 2021-05-25 21:09 UTC (permalink / raw)
To: Daniel Latypov
Cc: Linux Kernel Mailing List, andy, Andrew Morton, Oskar Schirmer
On Tue, May 25, 2021 at 10:34 AM Daniel Latypov <dlatypov@google.com> wrote:
> On Tue, May 25, 2021 at 7:43 AM Trent Piepho <tpiepho@gmail.com> wrote:
> > Adds a number of test cases that cover a range of possible code paths.
> >
> > Signed-off-by: Trent Piepho <tpiepho@gmail.com>
>
> Reviewed-by: Daniel Latypov <dlatypov@google.com>
>
> Looks really good to me, just two nits.
>
> Tangent:
> I didn't check to see that this covers all the interesting cases, but
> it seems like it does.
> If you want, you can try generating a code coverage report to double check.
> Instructions for doing so can be found in
> https://lore.kernel.org/linux-kselftest/20210414222256.1280532-1-dlatypov@google.com/
> I would have done that and included the #s in this email, but my
> workplace decided to subtly break my workstation in some way and I
> haven't gotten around to root causing...
I installed a gcc 6.4 toolchain and changed the uml_abort() call to
exit(), coverage was generated, but still truncated and incorrectly
near 0%. So what I did was crash after running all the test cases I
cared about by dividing by zero and then coverage data was produced
correctly. It's 100% by lines. But I think both possibilities when
the largest semiconvergent is exactly half the previous convergent
aren't tested.
> > lib/math/rational-test.c | 56 ++++++++++++++++++++++++++++++++++++++++
>
> Ah, sorry, I forgot to mention this in the previous email.
> If you look at kunit/style.rst docs, you'll see the documentation now
> states a preference for the name of this file to be one of
> {rational_test.c, rational_kunit.c}
Before I chose a name, I checked every file with kunit tests cases,
and *-test was the most common naming pattern, including the sample
case. I would be nice if changing the docs to say something is a
standard also updated the code to make that reality.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2 2/2] lib/math/rational: Add Kunit test cases
2021-05-25 21:09 ` Trent Piepho
@ 2021-05-25 22:03 ` Daniel Latypov
0 siblings, 0 replies; 10+ messages in thread
From: Daniel Latypov @ 2021-05-25 22:03 UTC (permalink / raw)
To: Trent Piepho
Cc: Linux Kernel Mailing List, andy, Andrew Morton, Oskar Schirmer
On Tue, May 25, 2021 at 2:09 PM Trent Piepho <tpiepho@gmail.com> wrote:
>
> On Tue, May 25, 2021 at 10:34 AM Daniel Latypov <dlatypov@google.com> wrote:
> > On Tue, May 25, 2021 at 7:43 AM Trent Piepho <tpiepho@gmail.com> wrote:
> > > Adds a number of test cases that cover a range of possible code paths.
> > >
> > > Signed-off-by: Trent Piepho <tpiepho@gmail.com>
> >
> > Reviewed-by: Daniel Latypov <dlatypov@google.com>
> >
> > Looks really good to me, just two nits.
> >
> > Tangent:
> > I didn't check to see that this covers all the interesting cases, but
> > it seems like it does.
> > If you want, you can try generating a code coverage report to double check.
> > Instructions for doing so can be found in
> > https://lore.kernel.org/linux-kselftest/20210414222256.1280532-1-dlatypov@google.com/
> > I would have done that and included the #s in this email, but my
> > workplace decided to subtly break my workstation in some way and I
> > haven't gotten around to root causing...
>
> I installed a gcc 6.4 toolchain and changed the uml_abort() call to
> exit(), coverage was generated, but still truncated and incorrectly
> near 0%. So what I did was crash after running all the test cases I
> cared about by dividing by zero and then coverage data was produced
> correctly. It's 100% by lines. But I think both possibilities when
> the largest semiconvergent is exactly half the previous convergent
> aren't tested.
Yeah, it's finicky.
Hopefully Brendan's change to cleanly shutdown the kernel at the end
of the tests might make it a bit more robust (still probably requires
gcc-6).
Thanks for running it!
It's nice to know we have 100% (line) coverage.
>
> > > lib/math/rational-test.c | 56 ++++++++++++++++++++++++++++++++++++++++
> >
> > Ah, sorry, I forgot to mention this in the previous email.
> > If you look at kunit/style.rst docs, you'll see the documentation now
> > states a preference for the name of this file to be one of
> > {rational_test.c, rational_kunit.c}
>
> Before I chose a name, I checked every file with kunit tests cases,
> and *-test was the most common naming pattern, including the sample
> case. I would be nice if changing the docs to say something is a
> standard also updated the code to make that reality.
Yeah, it's frustrating...
Andy sent out some changes renaming a lot of the files, but we've not
managed to get everything up to date.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v2 2/2] lib/math/rational: Add Kunit test cases
2021-05-25 14:42 ` [PATCH v2 2/2] lib/math/rational: Add Kunit test cases Trent Piepho
2021-05-25 16:00 ` Andy Shevchenko
2021-05-25 17:34 ` Daniel Latypov
@ 2021-05-25 21:49 ` Andrew Morton
2 siblings, 0 replies; 10+ messages in thread
From: Andrew Morton @ 2021-05-25 21:49 UTC (permalink / raw)
To: Trent Piepho; +Cc: linux-kernel, andy, oskar, Daniel Latypov
On Tue, 25 May 2021 07:42:50 -0700 Trent Piepho <tpiepho@gmail.com> wrote:
> Adds a number of test cases that cover a range of possible code paths.
>
> --- /dev/null
> +++ b/lib/math/rational-test.c
> @@ -0,0 +1,56 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <kunit/test.h>
> +
> +#include <linux/rational.h>
> +
> +struct rational_test_param {
> + unsigned long num, den;
> + unsigned long max_num, max_den;
> + unsigned long exp_num, exp_den;
> +
> + const char *name;
> +};
> +
> +static const struct rational_test_param test_parameters[] = {
> + { 1230, 10, 100, 20, 100, 1, "Exceeds bounds, semi-convergent term > ½ last term" },
> + { 34567,100, 120, 20, 120, 1, "Exceeds bounds, semi-convergent term < ½ last term" },
It seems to be asking for trouble to use these characters in kernel
output - heaven knows what sort of weird output devices people
are using. So I think I'll switch to "1/2", OK?
> + { 1, 30, 100, 10, 0, 1, "Closest to zero" },
> + { 1, 19, 100, 10, 1, 10, "Closest to smallest non-zero" },
> + { 27,32, 16, 16, 11, 13, "Use convergent" },
> + { 1155, 7735, 255, 255, 33, 221, "Exact answer" },
> + { 87, 32, 70, 32, 68, 25, "Semiconvergent, numerator limit" },
> + { 14533, 4626, 15000, 2400, 7433, 2366, "Semiconvergent, demominator limit" },
> +};
> ...
> +static struct kunit_case rational_test_cases[] = {
> + KUNIT_CASE_PARAM(rational_test, rational_gen_params),
> + {}
> +};
> +
> +static struct kunit_suite rational_test_suite = {
> + .name = "rational",
> + .test_cases = rational_test_cases,
> +};
And let's use tabs to indent here. checkpatch detects this.
^ permalink raw reply [flat|nested] 10+ messages in thread