[PATCH v2 1/4] lib/test: Introduce cpumask KUnit test suite

[Sander Vanheule]

Add a basic suite of tests for cpumask, providing some tests for empty
and completely filled cpumasks.

Signed-off-by: Sander Vanheule <sander@xxxxxxxxxxxxx>
---
 lib/Kconfig.debug  |   9 ++++
 lib/Makefile       |   1 +
 lib/test_cpumask.c | 115 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 125 insertions(+)
 create mode 100644 lib/test_cpumask.c

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index b8cc65d22169..85f2eb5c0b07 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2100,6 +2100,15 @@ config LKDTM
 	Documentation on how to use the module can be found in
 	Documentation/fault-injection/provoke-crashes.rst
 
+config TEST_CPUMASK
+	tristate "cpumask tests" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  Enable to turn on cpumask tests, running at boot or module load time.
+
+	  If unsure, say N.
+
 config TEST_LIST_SORT
 	tristate "Linked list sorting test" if !KUNIT_ALL_TESTS
 	depends on KUNIT
diff --git a/lib/Makefile b/lib/Makefile
index 89fcae891361..81f944cd74ae 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -100,6 +100,7 @@ obj-$(CONFIG_TEST_HMM) += test_hmm.o
 obj-$(CONFIG_TEST_FREE_PAGES) += test_free_pages.o
 obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
 obj-$(CONFIG_TEST_REF_TRACKER) += test_ref_tracker.o
+obj-$(CONFIG_TEST_CPUMASK) += test_cpumask.o
 CFLAGS_test_fprobe.o += $(CC_FLAGS_FTRACE)
 obj-$(CONFIG_FPROBE_SANITY_TEST) += test_fprobe.o
 #
diff --git a/lib/test_cpumask.c b/lib/test_cpumask.c
new file mode 100644
index 000000000000..3b69fcb6730e
--- /dev/null
+++ b/lib/test_cpumask.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * KUnit tests for cpumask.
+ *
+ * Author: Sander Vanheule <sander@xxxxxxxxxxxxx>
+ */
+
+#include <kunit/test.h>
+#include <linux/cpumask.h>
+
+#define FOR_EACH_ITER_EQ(_test, _iter, _expect, _loop)		\
+	do {							\
+		(_iter) = 0;					\
+		_loop						\
+			(_iter)++;				\
+		KUNIT_EXPECT_EQ((_test), (_expect), (_iter));	\
+	} while (0)
+
+static cpumask_t mask_empty;
+static cpumask_t mask_all;
+
+static void test_cpumask_weight(struct kunit *test)
+{
+	KUNIT_EXPECT_TRUE(test, cpumask_empty(&mask_empty));
+	KUNIT_EXPECT_TRUE(test, cpumask_full(cpu_possible_mask));
+	KUNIT_EXPECT_TRUE(test, cpumask_full(&mask_all));
+
+	KUNIT_EXPECT_EQ(test, 0, cpumask_weight(&mask_empty));
+	KUNIT_EXPECT_EQ(test, nr_cpu_ids, cpumask_weight(cpu_possible_mask));
+	KUNIT_EXPECT_EQ(test, nr_cpumask_bits, cpumask_weight(&mask_all));
+}
+
+static void test_cpumask_first(struct kunit *test)
+{
+	KUNIT_EXPECT_LE(test, nr_cpu_ids, cpumask_first(&mask_empty));
+	KUNIT_EXPECT_EQ(test, 0, cpumask_first(cpu_possible_mask));
+
+	KUNIT_EXPECT_EQ(test, 0, cpumask_first_zero(&mask_empty));
+	KUNIT_EXPECT_LE(test, nr_cpu_ids, cpumask_first_zero(cpu_possible_mask));
+}
+
+static void test_cpumask_last(struct kunit *test)
+{
+	KUNIT_EXPECT_LE(test, nr_cpumask_bits, cpumask_last(&mask_empty));
+	KUNIT_EXPECT_EQ(test, nr_cpumask_bits - 1, cpumask_last(cpu_possible_mask));
+}
+
+static void test_cpumask_next(struct kunit *test)
+{
+	KUNIT_EXPECT_EQ(test, 0, cpumask_next_zero(-1, &mask_empty));
+	KUNIT_EXPECT_LE(test, nr_cpu_ids, cpumask_next_zero(-1, cpu_possible_mask));
+
+	KUNIT_EXPECT_LE(test, nr_cpu_ids, cpumask_next(-1, &mask_empty));
+	KUNIT_EXPECT_EQ(test, 0, cpumask_next(-1, cpu_possible_mask));
+}
+
+static void test_cpumask_iterators(struct kunit *test)
+{
+	unsigned int iterations;
+	int cpu;
+
+	FOR_EACH_ITER_EQ(test, iterations, cpumask_weight(&mask_empty),
+			for_each_cpu(cpu, &mask_empty));
+	FOR_EACH_ITER_EQ(test, iterations, nr_cpu_ids - cpumask_weight(&mask_empty),
+			for_each_cpu_not(cpu, &mask_empty));
+	FOR_EACH_ITER_EQ(test, iterations, cpumask_weight(&mask_empty),
+			for_each_cpu_wrap(cpu, &mask_empty, nr_cpu_ids / 2));
+
+	FOR_EACH_ITER_EQ(test, iterations, cpumask_weight(cpu_possible_mask),
+			for_each_cpu(cpu, cpu_possible_mask));
+	FOR_EACH_ITER_EQ(test, iterations, nr_cpu_ids - cpumask_weight(cpu_possible_mask),
+			for_each_cpu_not(cpu, cpu_possible_mask));
+	FOR_EACH_ITER_EQ(test, iterations, cpumask_weight(cpu_possible_mask),
+			for_each_cpu_wrap(cpu, cpu_possible_mask, nr_cpu_ids / 2));
+}
+
+static void test_cpumask_iterators_builtin(struct kunit *test)
+{
+	unsigned int iterations;
+	int cpu;
+
+	FOR_EACH_ITER_EQ(test, iterations, nr_cpu_ids,
+		for_each_possible_cpu(cpu));
+	FOR_EACH_ITER_EQ(test, iterations, cpumask_weight(cpu_online_mask),
+		for_each_online_cpu(cpu));
+	FOR_EACH_ITER_EQ(test, iterations, cpumask_weight(cpu_present_mask),
+		for_each_present_cpu(cpu));
+}
+
+static int test_cpumask_init(struct kunit *test)
+{
+	cpumask_clear(&mask_empty);
+	cpumask_setall(&mask_all);
+
+	return 0;
+}
+
+static struct kunit_case test_cpumask_cases[] = {
+	KUNIT_CASE(test_cpumask_weight),
+	KUNIT_CASE(test_cpumask_first),
+	KUNIT_CASE(test_cpumask_last),
+	KUNIT_CASE(test_cpumask_next),
+	KUNIT_CASE(test_cpumask_iterators),
+	KUNIT_CASE(test_cpumask_iterators_builtin),
+	{}
+};
+
+static struct kunit_suite test_cpumask_suite = {
+	.name = "cpumask",
+	.init = test_cpumask_init,
+	.test_cases = test_cpumask_cases,
+};
+kunit_test_suite(test_cpumask_suite);
+
+MODULE_LICENSE("GPL");
-- 
2.36.1