On Fri, Oct 18, 2019 at 02:55:49PM -0700, David Gow wrote: > Add a KUnit test for the kernel doubly linked list implementation in > include/linux/list.h > > Each test case (list_test_x) is focused on testing the behaviour of the > list function/macro 'x'. None of the tests pass invalid lists to these > macros, and so should behave identically with DEBUG_LIST enabled and > disabled. > > Note that, at present, it only tests the list_ types (not the > singly-linked hlist_), and does not yet test all of the > list_for_each_entry* macros (and some related things like > list_prepare_entry). > > Signed-off-by: David Gow <david...@google.com> > --- > > The changes from v3 are mostly to do with naming: > - The Kconfig entry has been renamed from LIST_TEST to LIST_KUNIT_TEST, > which matches the SYSCTL_KUNIT_TEST entry, > - The Kconfig description was updated to better match other KUnit tests, > specifying that the test is not intended for use in a production > kernel. A now-redundant mention of the test running a boot was > removed. > - The MAINTAINERS entry refers to a "KUNIT TEST" rather than a "UNIT > TEST" > - The module name has changed from "list-test" to "list-kunit-test". > > Earlier versions of the test can be found: > v3: > https://lore.kernel.org/linux-kselftest/20191016215707.95317-1-david...@google.com/ > v2: > https://lore.kernel.org/linux-kselftest/20191010185631.26541-1-david...@google.com/ > v1: > https://lore.kernel.org/linux-kselftest/20191007213633.92565-1-david...@google.com/ > > MAINTAINERS | 5 + > lib/Kconfig.debug | 18 ++ > lib/Makefile | 3 + > lib/list-test.c | 740 ++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 766 insertions(+) > create mode 100644 lib/list-test.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 7ef985e01457..7ced1b69a3d3 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -9504,6 +9504,11 @@ F: Documentation/misc-devices/lis3lv02d.rst > F: drivers/misc/lis3lv02d/ > F: drivers/platform/x86/hp_accel.c > > +LIST KUNIT TEST > +M: David Gow <david...@google.com> > +S: Maintained > +F: lib/list-test.c > + > LIVE PATCHING > M: Josh Poimboeuf <jpoim...@redhat.com> > M: Jiri Kosina <ji...@kernel.org> > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index a3017a5dadcd..7991b78eb1f3 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -1961,6 +1961,24 @@ config SYSCTL_KUNIT_TEST > > If unsure, say N. > > +config LIST_KUNIT_TEST > + bool "KUnit Test for Kernel Linked-list structures" > + depends on KUNIT > + help > + This builds the linked list KUnit test suite. > + It tests that the API and basic functionality of the list_head type > + and associated macros. > + > + KUnit tests run during boot and output the results to the debug log > + in TAP format (http://testanything.org/). Only useful for kernel devs > + running the KUnit test harness, and not intended for inclusion into a > + production build. > + > + 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/Makefile b/lib/Makefile > index bba1fd5485f7..890e581d00c4 100644 > --- a/lib/Makefile > +++ b/lib/Makefile > @@ -292,3 +292,6 @@ obj-$(CONFIG_GENERIC_LIB_MULDI3) += muldi3.o > obj-$(CONFIG_GENERIC_LIB_CMPDI2) += cmpdi2.o > obj-$(CONFIG_GENERIC_LIB_UCMPDI2) += ucmpdi2.o > obj-$(CONFIG_OBJAGG) += objagg.o > + > +# KUnit tests > +obj-$(CONFIG_LIST_KUNIT_TEST) += list-test.o > diff --git a/lib/list-test.c b/lib/list-test.c > new file mode 100644 > index 000000000000..75ba3ddac959 > --- /dev/null > +++ b/lib/list-test.c > @@ -0,0 +1,740 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * KUnit test for the Kernel Linked-list structures. > + * > + * Copyright (C) 2019, Google LLC. > + * Author: David Gow <david...@google.com> > + */ > +#include <kunit/test.h> > + > +#include <linux/list.h> > + > +struct list_test_struct { > + int data; > + struct list_head list; > +}; > + > +static void list_test_list_init(struct kunit *test) > +{ > + /* Test the different ways of initialising a list. */ > + struct list_head list1 = LIST_HEAD_INIT(list1); > + struct list_head list2; > + LIST_HEAD(list3); > + struct list_head *list4; > + struct list_head *list5; > + > + INIT_LIST_HEAD(&list2); > + > + list4 = kzalloc(sizeof(*list4), GFP_KERNEL); > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, list4);
Why not just use GFP_KERNEL | GFP_NOFAIL and remove the check? kzalloc() can't return error pointers. If this were an IS_ERR_OR_NULL() check then it would generate a static checker warning, but static checkers don't know about KUNIT_ASSERT_NOT_ERR_OR_NULL() yet so you're safe. But generally NULL is a special case of success. A common situation is where the user deliberately disables a feature, that means it's not an error but we also don't have a valid pointer to return because it's disabled. regards, dan carpenter
