Re: [PATCH v5 07/12] kunit: test: create a single centralized executor for all tests

From: Brendan Higgins
Date: Tue Aug 04 2020 - 16:06:26 EST


On Fri, Jun 26, 2020 at 2:29 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>
> On Fri, Jun 26, 2020 at 02:09:12PM -0700, Brendan Higgins wrote:
> > From: Alan Maguire <alan.maguire@xxxxxxxxxx>
> >
> > Add a centralized executor to dispatch tests rather than relying on
> > late_initcall to schedule each test suite separately. Centralized
> > execution is for built-in tests only; modules will execute tests when
> > loaded.
> >
> > Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
> > Co-developed-by: Iurii Zaikin <yzaikin@xxxxxxxxxx>
> > Signed-off-by: Iurii Zaikin <yzaikin@xxxxxxxxxx>
> > Co-developed-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
> > Signed-off-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
> > Reviewed-by: Stephen Boyd <sboyd@xxxxxxxxxx>
> > ---
> > include/kunit/test.h | 67 +++++++++++++++++++++++++++++---------------
> > lib/kunit/Makefile | 3 +-
> > lib/kunit/executor.c | 28 ++++++++++++++++++
> > lib/kunit/test.c | 2 +-
> > 4 files changed, 76 insertions(+), 24 deletions(-)
> > create mode 100644 lib/kunit/executor.c
> >
> > diff --git a/include/kunit/test.h b/include/kunit/test.h
> > index 47e61e1d53370..f3e86c3953a2b 100644
> > --- a/include/kunit/test.h
> > +++ b/include/kunit/test.h
> > @@ -224,7 +224,7 @@ size_t kunit_suite_num_test_cases(struct kunit_suite *suite);
> > unsigned int kunit_test_case_num(struct kunit_suite *suite,
> > struct kunit_case *test_case);
> >
> > -int __kunit_test_suites_init(struct kunit_suite **suites);
> > +int __kunit_test_suites_init(struct kunit_suite * const * const suites);
> >
> > void __kunit_test_suites_exit(struct kunit_suite **suites);
> >
> > @@ -237,34 +237,57 @@ void __kunit_test_suites_exit(struct kunit_suite **suites);
> > * Registers @suites_list with the test framework. See &struct kunit_suite for
> > * more information.
> > *
> > - * When builtin, KUnit tests are all run as late_initcalls; this means
> > - * that they cannot test anything where tests must run at a different init
> > - * phase. One significant restriction resulting from this is that KUnit
> > - * cannot reliably test anything that is initialize in the late_init phase;
> > - * another is that KUnit is useless to test things that need to be run in
> > - * an earlier init phase.
> > - *
> > - * An alternative is to build the tests as a module. Because modules
> > - * do not support multiple late_initcall()s, we need to initialize an
> > - * array of suites for a module.
> > - *
> > - * TODO(brendanhiggins@xxxxxxxxxx): Don't run all KUnit tests as
> > - * late_initcalls. I have some future work planned to dispatch all KUnit
> > - * tests from the same place, and at the very least to do so after
> > - * everything else is definitely initialized.
> > + * If a test suite is built-in, module_init() gets translated into
> > + * an initcall which we don't want as the idea is that for builtins
> > + * the executor will manage execution. So ensure we do not define
> > + * module_{init|exit} functions for the builtin case when registering
> > + * suites via kunit_test_suites() below.
> > */
> > -#define kunit_test_suites(suites_list...) \
> > - static struct kunit_suite *suites[] = {suites_list, NULL}; \
> > - static int kunit_test_suites_init(void) \
> > +#ifdef MODULE
> > +#define kunit_test_suites_for_module(__suites) \
> > + static int __init kunit_test_suites_init(void) \
> > { \
> > - return __kunit_test_suites_init(suites); \
> > + return __kunit_test_suites_init(__suites); \
> > } \
> > - late_initcall(kunit_test_suites_init); \
> > + module_init(kunit_test_suites_init); \
> > + \
> > static void __exit kunit_test_suites_exit(void) \
> > { \
> > - return __kunit_test_suites_exit(suites); \
> > + return __kunit_test_suites_exit(__suites); \
> > } \
> > module_exit(kunit_test_suites_exit)
> > +#else
> > +#define kunit_test_suites_for_module(__suites)
> > +#endif /* MODULE */
> > +
> > +#define __kunit_test_suites(unique_array, unique_suites, ...) \
> > + static struct kunit_suite *unique_array[] = { __VA_ARGS__, NULL }; \
> > + kunit_test_suites_for_module(unique_array); \
> > + static struct kunit_suite **unique_suites \
> > + __used __section(.kunit_test_suites) = unique_array
> > +
> > +/**
> > + * kunit_test_suites() - used to register one or more &struct kunit_suite
> > + * with KUnit.
> > + *
> > + * @suites: a statically allocated list of &struct kunit_suite.
> > + *
> > + * Registers @suites with the test framework. See &struct kunit_suite for
> > + * more information.
> > + *
> > + * When builtin, KUnit tests are all run via executor; this is done
> > + * by placing the array of struct kunit_suite * in the .kunit_test_suites
> > + * ELF section.
> > + *
> > + * An alternative is to build the tests as a module. Because modules do not
> > + * support multiple initcall()s, we need to initialize an array of suites for a
> > + * module.
> > + *
> > + */
> > +#define kunit_test_suites(...) \
> > + __kunit_test_suites(__UNIQUE_ID(array), \
> > + __UNIQUE_ID(suites), \
> > + __VA_ARGS__)
> >
> > #define kunit_test_suite(suite) kunit_test_suites(&suite)
> >
> > diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile
> > index 724b94311ca36..c49f4ffb6273a 100644
> > --- a/lib/kunit/Makefile
> > +++ b/lib/kunit/Makefile
> > @@ -3,7 +3,8 @@ obj-$(CONFIG_KUNIT) += kunit.o
> > kunit-objs += test.o \
> > string-stream.o \
> > assert.o \
> > - try-catch.o
> > + try-catch.o \
> > + executor.o
> >
> > ifeq ($(CONFIG_KUNIT_DEBUGFS),y)
> > kunit-objs += debugfs.o
> > diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
> > new file mode 100644
> > index 0000000000000..7015e7328dce7
> > --- /dev/null
> > +++ b/lib/kunit/executor.c
> > @@ -0,0 +1,28 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +
> > +#include <kunit/test.h>
> > +
> > +/*
> > + * These symbols point to the .kunit_test_suites section and are defined in
> > + * include/asm-generic/vmlinux.lds.h, and consequently must be extern.
> > + */
> > +extern struct kunit_suite * const * const __kunit_suites_start[];
> > +extern struct kunit_suite * const * const __kunit_suites_end[];
>
> I would expect these to be in include/asm-generic/sections.h but I guess
> it's not required.

I don't have strong opinions either way, but I think this is less
clutter since KUnit is the only one that uses it.

> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

Thanks!