[RFC,2/2] drm: add documentation for drm_buddy_test kUnit test

  As an example for the new documentation tool, add a documentation
for drm_buddy_test.

I opted to place this on a completely different directory, in order
to make easier to test the feature with:

	$ make SPHINXDIRS="tests" htmldocs

Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
---

To avoid mailbombing on a large number of people, only mailing lists were C/C on the cover.
See [PATCH RFC 0/2] at: https://lore.kernel.org/all/cover.1689171160.git.mchehab@kernel.org/

 Documentation/index.rst                |  2 +-
 Documentation/tests/index.rst          |  6 ++++++
 Documentation/tests/kunit.rst          |  5 +++++
 drivers/gpu/drm/tests/drm_buddy_test.c | 12 ++++++++++++
 4 files changed, 24 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/tests/index.rst
 create mode 100644 Documentation/tests/kunit.rst
  

On Wed, 12 Jul 2023, Mauro Carvalho Chehab <mchehab@kernel.org> wrote:
> diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c b/drivers/gpu/drm/tests/drm_buddy_test.c
> index 09ee6f6af896..dd6c5afd6cd6 100644
> --- a/drivers/gpu/drm/tests/drm_buddy_test.c
> +++ b/drivers/gpu/drm/tests/drm_buddy_test.c
> @@ -737,6 +737,18 @@ static int drm_buddy_suite_init(struct kunit_suite *suite)
>  	return 0;
>  }
>  
> +/**
> + * KTEST_SUITE: set of tests for drm buddy alloc
> + * Scope: drm subsystem
> + * Mega feature: drm
> + * Feature: buddy_alloc
> + *
> + * KTEST_TEST: drm_test_buddy_alloc_%s
> + * Description: Run DRM buddy allocation %arg[1] test
> + *
> + * arg[1].values: limit, range, optimistic, smoke, pathological
> + */
> +

"/**" indicates a kernel-doc comment, and this is not a kernel-doc
comment.

$ scripts/kernel-doc -none drivers/gpu/drm/tests/drm_buddy_test.c 
drivers/gpu/drm/tests/drm_buddy_test.c:752: warning: cannot understand
function prototype: 'struct kunit_case drm_buddy_tests[] = '

Nowadays kernel-doc is part of W=1 builds.


BR,
Jani.


>  static struct kunit_case drm_buddy_tests[] = {
>  	KUNIT_CASE(drm_test_buddy_alloc_limit),
>  	KUNIT_CASE(drm_test_buddy_alloc_range),
  

Em Wed, 12 Jul 2023 18:03:00 +0300
Jani Nikula <jani.nikula@linux.intel.com> escreveu:

> On Wed, 12 Jul 2023, Mauro Carvalho Chehab <mchehab@kernel.org> wrote:
> > diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c b/drivers/gpu/drm/tests/drm_buddy_test.c
> > index 09ee6f6af896..dd6c5afd6cd6 100644
> > --- a/drivers/gpu/drm/tests/drm_buddy_test.c
> > +++ b/drivers/gpu/drm/tests/drm_buddy_test.c
> > @@ -737,6 +737,18 @@ static int drm_buddy_suite_init(struct kunit_suite *suite)
> >  	return 0;
> >  }
> >  
> > +/**
> > + * KTEST_SUITE: set of tests for drm buddy alloc
> > + * Scope: drm subsystem
> > + * Mega feature: drm
> > + * Feature: buddy_alloc
> > + *
> > + * KTEST_TEST: drm_test_buddy_alloc_%s
> > + * Description: Run DRM buddy allocation %arg[1] test
> > + *
> > + * arg[1].values: limit, range, optimistic, smoke, pathological
> > + */
> > +  
> 
> "/**" indicates a kernel-doc comment, and this is not a kernel-doc
> comment.
> 
> $ scripts/kernel-doc -none drivers/gpu/drm/tests/drm_buddy_test.c 
> drivers/gpu/drm/tests/drm_buddy_test.c:752: warning: cannot understand
> function prototype: 'struct kunit_case drm_buddy_tests[] = '
> 
> Nowadays kernel-doc is part of W=1 builds.

True. I already told it at patch 0. I opted to not add a patch for it on this
RFC series, to make it simpler. A simple logic at kernel-doc is enough to 
tell its state machine to ignore blocks that contain the KTEST_\w+: pattern:

diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index d0116c6939dc..bf386460691f 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -259,6 +259,7 @@ my $doc_sect = $doc_com .
     '\s*(\@[.\w]+|\@\.\.\.|description|context|returns?|notes?|examples?)\s*:([^:].*)?$';
 my $doc_content = $doc_com_body . '(.*)';
 my $doc_block = $doc_com . 'DOC:\s*(.*)?';
+my $ktest_block = $doc_com . 'KTEST_\w+:\s*(.*)?';
 my $doc_inline_start = '^\s*/\*\*\s*$';
 my $doc_inline_sect = '\s*\*\s*(@\s*[\w][\w\.]*\s*):(.*)';
 my $doc_inline_end = '^\s*\*/\s*$';
@@ -2015,6 +2016,10 @@ sub process_name($$) {
     my $file = shift;
     my $descr;
 
+    if (/$ktest_block/o) {
+	$state = STATE_NORMAL;
+	return;
+    }
     if (/$doc_block/o) {
 	$state = STATE_DOCBLOCK;
 	$contents = "";



Thanks,
Mauro
  

[Adding Arun]

Am 12.07.23 um 16:28 schrieb Mauro Carvalho Chehab:
> As an example for the new documentation tool, add a documentation
> for drm_buddy_test.
>
> I opted to place this on a completely different directory, in order
> to make easier to test the feature with:
>
> 	$ make SPHINXDIRS="tests" htmldocs
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Acked-by: Christian König <christian.koenig@amd.com>

Arun please take a look as well.

Thanks,
Christian.

> ---
>
> To avoid mailbombing on a large number of people, only mailing lists were C/C on the cover.
> See [PATCH RFC 0/2] at: https://lore.kernel.org/all/cover.1689171160.git.mchehab@kernel.org/
>
>   Documentation/index.rst                |  2 +-
>   Documentation/tests/index.rst          |  6 ++++++
>   Documentation/tests/kunit.rst          |  5 +++++
>   drivers/gpu/drm/tests/drm_buddy_test.c | 12 ++++++++++++
>   4 files changed, 24 insertions(+), 1 deletion(-)
>   create mode 100644 Documentation/tests/index.rst
>   create mode 100644 Documentation/tests/kunit.rst
>
> diff --git a/Documentation/index.rst b/Documentation/index.rst
> index 9dfdc826618c..80a6ce14a61a 100644
> --- a/Documentation/index.rst
> +++ b/Documentation/index.rst
> @@ -60,7 +60,7 @@ Various other manuals with useful information for all kernel developers.
>      fault-injection/index
>      livepatch/index
>      rust/index
> -
> +   test/index
>   
>   User-oriented documentation
>   ===========================
> diff --git a/Documentation/tests/index.rst b/Documentation/tests/index.rst
> new file mode 100644
> index 000000000000..bfc39eb5c0aa
> --- /dev/null
> +++ b/Documentation/tests/index.rst
> @@ -0,0 +1,6 @@
> +========================
> +Kunit documentation test
> +========================
> +
> +.. toctree::
> +   kunit
> diff --git a/Documentation/tests/kunit.rst b/Documentation/tests/kunit.rst
> new file mode 100644
> index 000000000000..6ffc151988a0
> --- /dev/null
> +++ b/Documentation/tests/kunit.rst
> @@ -0,0 +1,5 @@
> +Kunit tests
> +-----------
> +
> +.. include-test:: drivers/gpu/drm/tests/drm_buddy_test.c
> +
> diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c b/drivers/gpu/drm/tests/drm_buddy_test.c
> index 09ee6f6af896..dd6c5afd6cd6 100644
> --- a/drivers/gpu/drm/tests/drm_buddy_test.c
> +++ b/drivers/gpu/drm/tests/drm_buddy_test.c
> @@ -737,6 +737,18 @@ static int drm_buddy_suite_init(struct kunit_suite *suite)
>   	return 0;
>   }
>   
> +/**
> + * KTEST_SUITE: set of tests for drm buddy alloc
> + * Scope: drm subsystem
> + * Mega feature: drm
> + * Feature: buddy_alloc
> + *
> + * KTEST_TEST: drm_test_buddy_alloc_%s
> + * Description: Run DRM buddy allocation %arg[1] test
> + *
> + * arg[1].values: limit, range, optimistic, smoke, pathological
> + */
> +
>   static struct kunit_case drm_buddy_tests[] = {
>   	KUNIT_CASE(drm_test_buddy_alloc_limit),
>   	KUNIT_CASE(drm_test_buddy_alloc_range),
  

On Wed, Jul 12, 2023 at 10:29 AM Mauro Carvalho Chehab
<mchehab@kernel.org> wrote:
>
> As an example for the new documentation tool, add a documentation
> for drm_buddy_test.
>
> I opted to place this on a completely different directory, in order
> to make easier to test the feature with:
>
>         $ make SPHINXDIRS="tests" htmldocs
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
> ---
>
> To avoid mailbombing on a large number of people, only mailing lists were C/C on the cover.
> See [PATCH RFC 0/2] at: https://lore.kernel.org/all/cover.1689171160.git.mchehab@kernel.org/
>
>  Documentation/index.rst                |  2 +-
>  Documentation/tests/index.rst          |  6 ++++++
>  Documentation/tests/kunit.rst          |  5 +++++
>  drivers/gpu/drm/tests/drm_buddy_test.c | 12 ++++++++++++
>  4 files changed, 24 insertions(+), 1 deletion(-)
>  create mode 100644 Documentation/tests/index.rst
>  create mode 100644 Documentation/tests/kunit.rst
>
> diff --git a/Documentation/index.rst b/Documentation/index.rst
> index 9dfdc826618c..80a6ce14a61a 100644
> --- a/Documentation/index.rst
> +++ b/Documentation/index.rst
> @@ -60,7 +60,7 @@ Various other manuals with useful information for all kernel developers.
>     fault-injection/index
>     livepatch/index
>     rust/index
> -
> +   test/index
>
>  User-oriented documentation
>  ===========================
> diff --git a/Documentation/tests/index.rst b/Documentation/tests/index.rst
> new file mode 100644
> index 000000000000..bfc39eb5c0aa
> --- /dev/null
> +++ b/Documentation/tests/index.rst
> @@ -0,0 +1,6 @@
> +========================
> +Kunit documentation test
> +========================
> +
> +.. toctree::
> +   kunit
> diff --git a/Documentation/tests/kunit.rst b/Documentation/tests/kunit.rst
> new file mode 100644
> index 000000000000..6ffc151988a0
> --- /dev/null
> +++ b/Documentation/tests/kunit.rst
> @@ -0,0 +1,5 @@
> +Kunit tests
> +-----------
> +
> +.. include-test:: drivers/gpu/drm/tests/drm_buddy_test.c
> +
> diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c b/drivers/gpu/drm/tests/drm_buddy_test.c
> index 09ee6f6af896..dd6c5afd6cd6 100644
> --- a/drivers/gpu/drm/tests/drm_buddy_test.c
> +++ b/drivers/gpu/drm/tests/drm_buddy_test.c
> @@ -737,6 +737,18 @@ static int drm_buddy_suite_init(struct kunit_suite *suite)
>         return 0;
>  }
>
> +/**
> + * KTEST_SUITE: set of tests for drm buddy alloc
> + * Scope: drm subsystem
> + * Mega feature: drm
> + * Feature: buddy_alloc
> + *
> + * KTEST_TEST: drm_test_buddy_alloc_%s
> + * Description: Run DRM buddy allocation %arg[1] test
> + *
> + * arg[1].values: limit, range, optimistic, smoke, pathological
> + */
> +

I apologize that the last email included a HTML attachment of the message.

Just in case anyone was unable to receive the last email here is a
copy of the message:

Hi!

This is such a cool patch series. I just have a few comments related
to the output.

In the html output the tests are listed as:
ktest@drm_buddy_test@...

I wonder if instead of using the file name of "drm_buddy_test" this
could possibly be the suite name, "drm_buddy", as this is what users
will call when using kunit.py to run the tests. Although
"drm_buddy_test" is also the module name so I don't mind it too much.
But in the future the file name and module name are not guaranteed to
be the same for other tests.

Most preferably, there would be a reference to the kunit suite name,
file name, and the module name.

This may be difficult to implement as these can all differ. I am
currently working on the KUnit Attribute framework which saves the
module name and I am thinking about also saving the file path as a
future attribute. This could be a helpful framework for the KUnit
tests specifically.

I am not sure how easy it would be to access c objects/functions using
this system.

Finally, I was wondering if it is the intention to put a list of all
KUnit tests that use this new feature into tests/kunit.rst or would
this be broken up in some way.

Thanks!
-Rae

>  static struct kunit_case drm_buddy_tests[] = {
>         KUNIT_CASE(drm_test_buddy_alloc_limit),
>         KUNIT_CASE(drm_test_buddy_alloc_range),
> --
> 2.40.1
>
  

Hi Rae,

Em Thu, 13 Jul 2023 17:31:19 -0400
Rae Moar <rmoar@google.com> escreveu:

> On Wed, Jul 12, 2023 at 10:29 AM Mauro Carvalho Chehab <mchehab@kernel.org>
> wrote:
> 
> > As an example for the new documentation tool, add a documentation
> > for drm_buddy_test.
> >
> > I opted to place this on a completely different directory, in order
> > to make easier to test the feature with:
> >
> >         $ make SPHINXDIRS="tests" htmldocs
> >
> > Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
> > ---
> >
> > To avoid mailbombing on a large number of people, only mailing lists were
> > C/C on the cover.
> > See [PATCH RFC 0/2] at:
> > https://lore.kernel.org/all/cover.1689171160.git.mchehab@kernel.org/
> >
> >  Documentation/index.rst                |  2 +-
> >  Documentation/tests/index.rst          |  6 ++++++
> >  Documentation/tests/kunit.rst          |  5 +++++
> >  drivers/gpu/drm/tests/drm_buddy_test.c | 12 ++++++++++++
> >  4 files changed, 24 insertions(+), 1 deletion(-)
> >  create mode 100644 Documentation/tests/index.rst
> >  create mode 100644 Documentation/tests/kunit.rst
> >
> > diff --git a/Documentation/index.rst b/Documentation/index.rst
> > index 9dfdc826618c..80a6ce14a61a 100644
> > --- a/Documentation/index.rst
> > +++ b/Documentation/index.rst
> > @@ -60,7 +60,7 @@ Various other manuals with useful information for all
> > kernel developers.
> >     fault-injection/index
> >     livepatch/index
> >     rust/index
> > -
> > +   test/index
> >
> >  User-oriented documentation
> >  ===========================
> > diff --git a/Documentation/tests/index.rst b/Documentation/tests/index.rst
> > new file mode 100644
> > index 000000000000..bfc39eb5c0aa
> > --- /dev/null
> > +++ b/Documentation/tests/index.rst
> > @@ -0,0 +1,6 @@
> > +========================
> > +Kunit documentation test
> > +========================
> > +
> > +.. toctree::
> > +   kunit
> > diff --git a/Documentation/tests/kunit.rst b/Documentation/tests/kunit.rst
> > new file mode 100644
> > index 000000000000..6ffc151988a0
> > --- /dev/null
> > +++ b/Documentation/tests/kunit.rst
> > @@ -0,0 +1,5 @@
> > +Kunit tests
> > +-----------
> > +
> > +.. include-test:: drivers/gpu/drm/tests/drm_buddy_test.c
> > +
> > diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c
> > b/drivers/gpu/drm/tests/drm_buddy_test.c
> > index 09ee6f6af896..dd6c5afd6cd6 100644
> > --- a/drivers/gpu/drm/tests/drm_buddy_test.c
> > +++ b/drivers/gpu/drm/tests/drm_buddy_test.c
> > @@ -737,6 +737,18 @@ static int drm_buddy_suite_init(struct kunit_suite
> > *suite)
> >         return 0;
> >  }
> >
> > +/**
> > + * KTEST_SUITE: set of tests for drm buddy alloc
> > + * Scope: drm subsystem
> > + * Mega feature: drm
> > + * Feature: buddy_alloc
> > + *
> > + * KTEST_TEST: drm_test_buddy_alloc_%s
> > + * Description: Run DRM buddy allocation %arg[1] test
> > + *
> > + * arg[1].values: limit, range, optimistic, smoke, pathological
> > + */  
> 
> 
> Hi!
> 
> This is such a cool patch series. I just have a few comments related to the
> output.

Thank you for your comments! Sorry for not answering earlier. I took some
vacations and this series ended sleeping over other tasks on my
todo list.

Also, before sending another version, I wanted to have the test_list.py
changes to make it generic enough to be merged on IGT, to avoid having
a fork of it. Those got merged today.

> In the html output the tests are listed as:
> ktest@drm_buddy_test@…
> 
> I wonder if instead of using the file name of “drm_buddy_test” this could
> possibly be the suite name, “drm_buddy”, as this is what users will call
> when using kunit.py to run the tests. Although "drm_buddy_test" is also the
> module name so I don't mind it too much. But in the future the file name
> and module name are not guaranteed to be the same for other tests.
> 
> Most preferably, there would be a reference to the kunit suite name, file
> name, and the module name.

I guess it shouldn't be hard to do such change in a way that it won't
affect its usage on IGT. We need to define what would be the best
pattern. As this can be used for both kunit and selftests, I would
place kunit at the beginning.

Currently, we're using:

	kunit@<base file name without .c>@<test_name>

Some possible patterns would be:

	kunit@<base file name without .c>@<suite name>@<test_name>
	kunit@<subsystem>@<base file name without .c>@<suite name>@<test_name>
	kunit@<subsystem>@<suite name>@<test_name>

Would do you think it would work best?

> This may be difficult to implement as these can all differ. I am currently
> working on the KUnit Attribute framework which saves the module name and I
> am thinking about also saving the file path as a future attribute. This
> could be a helpful framework for the KUnit tests specifically.
> 
> I am not sure how easy it would be to access c objects/functions using this
> system.

I would prefer not. C language allows lots of flexibility with macros,
making it hard to write a parser to read those C objects from the source.
We have this at kernel-doc. As one of the people that did some work there,
I can say that that several tricks are needed to keep this working.

On the other hand, it should be easy to use the TestList class from
test_list.py at kunit.py.

So, kunit.py could use the data that came from the documentation
directly.

> Finally, I was wondering if it is the intention to put a list of all kunit
> tests that use this new feature into tests/kunit.rst or would this be
> broken up in some way

IMO, it makes sense to break this per subsystem, and have an auto-generated
index.rst pointing to the entire set of documents.

We're already storing the subsystem at the documentation macros, so, IMO,
it should shouldn't be hard to implement it.

Regards,
Mauro