[PATCH 5/5] riscv: Test checksum functions

From: Charlie Jenkins
Date: Sat Aug 26 2023 - 21:27:48 EST


Add Kconfig support for riscv specific testing modules. This was created
to supplement lib/checksum_kunit.c, and add tests for ip_fast_csum and
csum_ipv6_magic.

Signed-off-by: Charlie Jenkins <charlie@xxxxxxxxxxxx>
---
arch/riscv/Kconfig.debug | 1 +
arch/riscv/lib/Kconfig.debug | 31 ++++++++++
arch/riscv/lib/Makefile | 2 +
arch/riscv/lib/riscv_checksum_kunit.c | 111 ++++++++++++++++++++++++++++++++++
4 files changed, 145 insertions(+)

diff --git a/arch/riscv/Kconfig.debug b/arch/riscv/Kconfig.debug
index e69de29bb2d1..53a84ec4f91f 100644
--- a/arch/riscv/Kconfig.debug
+++ b/arch/riscv/Kconfig.debug
@@ -0,0 +1 @@
+source "arch/riscv/lib/Kconfig.debug"
diff --git a/arch/riscv/lib/Kconfig.debug b/arch/riscv/lib/Kconfig.debug
new file mode 100644
index 000000000000..15fc83b68340
--- /dev/null
+++ b/arch/riscv/lib/Kconfig.debug
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menu "riscv Testing and Coverage"
+
+menuconfig RUNTIME_TESTING_MENU
+ bool "Runtime Testing"
+ def_bool y
+ help
+ Enable riscv runtime testing.
+
+if RUNTIME_TESTING_MENU
+
+config RISCV_CHECKSUM_KUNIT
+ tristate "KUnit test riscv checksum functions at runtime" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ help
+ Enable this option to test the checksum functions at boot.
+
+ 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.
+
+endif # RUNTIME_TESTING_MENU
+
+endmenu # "riscv Testing and Coverage"
diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile
index 2aa1a4ad361f..1535a8c81430 100644
--- a/arch/riscv/lib/Makefile
+++ b/arch/riscv/lib/Makefile
@@ -12,3 +12,5 @@ lib-$(CONFIG_64BIT) += tishift.o
lib-$(CONFIG_RISCV_ISA_ZICBOZ) += clear_page.o

obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o
+
+obj-$(CONFIG_RISCV_CHECKSUM_KUNIT) += riscv_checksum_kunit.o
diff --git a/arch/riscv/lib/riscv_checksum_kunit.c b/arch/riscv/lib/riscv_checksum_kunit.c
new file mode 100644
index 000000000000..05b4710c907f
--- /dev/null
+++ b/arch/riscv/lib/riscv_checksum_kunit.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Test cases for checksum
+ */
+
+#include <linux/in6.h>
+
+#include <kunit/test.h>
+#include <net/checksum.h>
+#include <net/ip6_checksum.h>
+
+#define CHECK_EQ(lhs, rhs) KUNIT_ASSERT_EQ(test, lhs, rhs)
+
+static void test_csum_fold(struct kunit *test)
+{
+ unsigned int one = 1226127848;
+ unsigned int two = 446627905;
+ unsigned int three = 3644783064;
+ unsigned int four = 361842745;
+ unsigned int five = 4281073503;
+ unsigned int max = -1;
+
+ CHECK_EQ(0x7d02, csum_fold(one));
+ CHECK_EQ(0xe51f, csum_fold(two));
+ CHECK_EQ(0x2ce8, csum_fold(three));
+ CHECK_EQ(0xa235, csum_fold(four));
+ CHECK_EQ(0x174, csum_fold(five));
+ CHECK_EQ(0x0, csum_fold(max));
+}
+
+static void test_ip_fast_csum(struct kunit *test)
+{
+ unsigned char *average = { 0x1c, 0x00, 0x00, 0x45, 0x00, 0x00, 0x68,
+ 0x74, 0x00, 0x00, 0x11, 0x80, 0x01, 0x64,
+ 0xa8, 0xc0, 0xe9, 0x9c, 0x46, 0xab };
+ unsigned char *larger = { 0xa3, 0xde, 0x43, 0x41, 0x11, 0x19,
+ 0x2f, 0x73, 0x00, 0x00, 0xf1, 0xc5,
+ 0x31, 0xbb, 0xaa, 0xc1, 0x23, 0x5f,
+ 0x32, 0xde, 0x65, 0x39, 0xfe, 0xbc };
+ unsigned char *overflow = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xff, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+ unsigned char *max = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff,
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xff,
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
+
+ CHECK_EQ(0x598f, ip_fast_csum(average, 5));
+ CHECK_EQ(0xdd4f, ip_fast_csum(larger, 6));
+ CHECK_EQ(0xfffe, ip_fast_csum(overflow, 5));
+ CHECK_EQ(0x400, ip_fast_csum(max, 14));
+}
+
+static void test_csum_ipv6_magic(struct kunit *test)
+{
+ struct in6_addr saddr = {
+ .s6_addr = { 0xf8, 0x43, 0x43, 0xf0, 0xdc, 0xa0, 0x39, 0x92,
+ 0x43, 0x67, 0x12, 0x03, 0xe3, 0x32, 0xfe, 0xed }};
+ struct in6_addr daddr = {
+ .s6_addr = { 0xa8, 0x23, 0x46, 0xdc, 0xc8, 0x2d, 0xaa, 0xe3,
+ 0xdc, 0x66, 0x72, 0x43, 0xe2, 0x12, 0xee, 0xfd }};
+ u32 len = 1 << 10;
+ u8 proto = 17;
+ __wsum csum = 53;
+
+ CHECK_EQ(0x2fbb, csum_ipv6_magic(&saddr, &daddr, len, proto, csum));
+}
+
+static void test_do_csum(struct kunit *test)
+{
+ unsigned char *very_small = {0x32};
+ unsigned char *small = {0xd3, 0x43, 0xad, 0x46};
+ unsigned char *medium = {
+ 0xa0, 0x13, 0xaa, 0xa6, 0x53, 0xac, 0xa3, 0x43
+ };
+ unsigned char *misaligned = medium + 1;
+ unsigned char *large = {
+ 0xa0, 0x13, 0xaa, 0xa6, 0x53, 0xac, 0xa3, 0x43,
+ 0xa0, 0x13, 0xaa, 0xa6, 0x53, 0xac, 0xa3, 0x43,
+ 0xa0, 0x13, 0xaa, 0xa6, 0x53, 0xac, 0xa3, 0x43,
+ 0xa0, 0x13, 0xaa, 0xa6, 0x53, 0xac, 0xa3, 0x43
+ };
+ unsigned char *large_misaligned = large + 3;
+
+ CHECK_EQ(0xffcd, ip_compute_csum(very_small, 1));
+ CHECK_EQ(0x757f, ip_compute_csum(small, 4));
+ CHECK_EQ(0x5e56, ip_compute_csum(misaligned, 7));
+ CHECK_EQ(0x469d, ip_compute_csum(large, 29));
+ CHECK_EQ(0x43ae, ip_compute_csum(large_misaligned, 28));
+}
+
+static struct kunit_case __refdata riscv_checksum_test_cases[] = {
+ KUNIT_CASE(test_csum_fold),
+ KUNIT_CASE(test_ip_fast_csum),
+ KUNIT_CASE(test_csum_ipv6_magic),
+ KUNIT_CASE(test_do_csum),
+ {}
+};
+
+static struct kunit_suite riscv_checksum_test_suite = {
+ .name = "riscv_checksum",
+ .test_cases = riscv_checksum_test_cases,
+};
+
+kunit_test_suites(&riscv_checksum_test_suite);
+
+MODULE_AUTHOR("Charlie Jenkins <charlie@xxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");

--
2.41.0