kernel/sysctl-test: use SYSCTL_{ZERO/ONE_HUNDRED} instead of i_{zero/one_hundred}

It is better to use SYSCTL_ZERO and SYSCTL_ONE_HUNDRED instead of &i_zero
and &i_one_hundred, and then we can remove these two local variable.

No functional change.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

kernel/sysctl-test: Remove some casts which are no-longer required

With some of the stricter type checking in KUnit's EXPECT macros
removed, several casts in sysctl-test are no longer required.

Remove the unnecessary casts, making the conditions clearer.

Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

kunit: allow kunit tests to be loaded as a module

As tests are added to kunit, it will become less feasible to execute
all built tests together. By supporting modular tests we provide
a simple way to do selective execution on a running system; specifying

CONFIG_KUNIT=y
CONFIG_KUNIT_EXAMPLE_TEST=m

...means we can simply "insmod example-test.ko" to run the tests.

To achieve this we need to do the following:

o export the required symbols in kunit
o string-stream tests utilize non-exported symbols so for now we skip
building them when CONFIG_KUNIT_TEST=m.
o drivers/base/power/qos-test.c contains a few unexported interface
references, namely freq_qos_read_value() and freq_constraints_init().
Both of these could be potentially defined as static inline functions
in include/linux/pm_qos.h, but for now we simply avoid supporting
module build for that test suite.
o support a new way of declaring test suites. Because a module cannot
do multiple late_initcall()s, we provide a kunit_test_suites() macro
to declare multiple suites within the same module at once.
o some test module names would have been too general ("test-test"
and "example-test" for kunit tests, "inode-test" for ext4 tests);
rename these as appropriate ("kunit-test", "kunit-example-test"
and "ext4-inode-test" respectively).

Also define kunit_test_suite() via kunit_test_suites()
as callers in other trees may need the old definition.

Co-developed-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4 bits
Acked-by: David Gow <davidgow@google.com> # For list-test
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec()

KUnit tests for initialized data behavior of proc_dointvec that is
explicitly checked in the code. Includes basic parsing tests including
int min/max overflow.

Signed-off-by: Iurii Zaikin <yzaikin@google.com>
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>