[PATCH v6 19/19] kselftest: Extend vDSO selftest

Vincenzo Frascino
2019-05-30T14:16:54Z

The current version of the multiarch vDSO selftest verifies only
gettimeofday.

Extend the vDSO selftest to the other library functions:
- time
- clock_getres
- clock_gettime

The extension has been used to verify the unified vdso library on the
supported architectures.

Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
---
tools/testing/selftests/vDSO/Makefile | 2 +
tools/testing/selftests/vDSO/vdso_full_test.c | 261 ++++++++++++++++++
2 files changed, 263 insertions(+)
create mode 100644 tools/testing/selftests/vDSO/vdso_full_test.c

diff --git a/tools/testing/selftests/vDSO/Makefile b/tools/testing/selftests/vDSO/Makefile
index 9e03d61f52fd..68e9b4a1cdcf 100644
--- a/tools/testing/selftests/vDSO/Makefile
+++ b/tools/testing/selftests/vDSO/Makefile
@@ -5,6 +5,7 @@ uname_M := $(shell uname -m 2>/dev/null || echo not)
ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)

TEST_GEN_PROGS := $(OUTPUT)/vdso_test
+TEST_GEN_PROGS += $(OUTPUT)/vdso_full_test
ifeq ($(ARCH),x86)
TEST_GEN_PROGS += $(OUTPUT)/vdso_standalone_test_x86
endif
@@ -18,6 +19,7 @@ endif

all: $(TEST_GEN_PROGS)
$(OUTPUT)/vdso_test: parse_vdso.c vdso_test.c
+$(OUTPUT)/vdso_full_test: parse_vdso.c vdso_full_test.c
$(OUTPUT)/vdso_standalone_test_x86: vdso_standalone_test_x86.c parse_vdso.c
$(CC) $(CFLAGS) $(CFLAGS_vdso_standalone_test_x86) \
vdso_standalone_test_x86.c parse_vdso.c \
diff --git a/tools/testing/selftests/vDSO/vdso_full_test.c b/tools/testing/selftests/vDSO/vdso_full_test.c
new file mode 100644
index 000000000000..62001d3d241b
--- /dev/null
+++ b/tools/testing/selftests/vDSO/vdso_full_test.c
@@ -0,0 +1,261 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * vdso_full_test.c: Sample code to test all the timers.
+ * Copyright (c) 2019 Arm Ltd.
+ *
+ * Compile with:
+ * gcc -std=gnu99 vdso_full_test.c parse_vdso.c
+ *
+ * Tested on ARM, ARM64, MIPS32 and x86 (32-bit and 64-bit).
+ * Might work on other architectures.
+ */
+
+#include <stdint.h>
+#include <elf.h>
+#include <stdio.h>
+#include <time.h>
+#include <sys/auxv.h>
+#include <sys/time.h>
+#define _GNU_SOURCE
+#include <unistd.h>
+#include <sys/syscall.h>
+
+#include "../kselftest.h"
+
+extern void *vdso_sym(const char *version, const char *name);
+extern void vdso_init_from_sysinfo_ehdr(uintptr_t base);
+extern void vdso_init_from_auxv(void *auxv);
+
+/*
+ * ARM64's vDSO exports its vDSO implementation with different names and
+ * a different version from other architectures, so we need to handle it
+ * as a special case.
+ */
+#if defined(__aarch64__)
+const char *version = "LINUX_2.6.39";
+const char *name[4] = {
+ "__kernel_gettimeofday",
+ "__kernel_clock_gettime",
+ "__kernel_time",
+ "__kernel_clock_getres",
+};
+#else
+/* Tested on x86, arm, mips */
+const char *version = "LINUX_2.6";
+const char *name[4] = {
+ "__vdso_gettimeofday",
+ "__vdso_clock_gettime",
+ "__vdso_time",
+ "__vdso_clock_getres",
+};
+#endif
+
+typedef long (*vdso_gettimeofday_t)(struct timeval *tv, struct timezone *tz);
+typedef long (*vdso_clock_gettime_t)(clockid_t clk_id, struct timespec *ts);
+typedef long (*vdso_clock_getres_t)(clockid_t clk_id, struct timespec *ts);
+typedef time_t (*vdso_time_t)(time_t *t);
+
+static int vdso_test_gettimeofday(void)
+{
+ /* Find gettimeofday. */
+ vdso_gettimeofday_t vdso_gettimeofday =
+ (vdso_gettimeofday_t)vdso_sym(version, name[0]);
+
+ if (!vdso_gettimeofday) {
+ printf("Could not find %s\n", name[0]);
+ return KSFT_SKIP;
+ }
+
+ struct timeval tv;
+ long ret = vdso_gettimeofday(&tv, 0);
+
+ if (ret == 0) {
+ printf("The time is %lld.%06lld\n",
+ (long long)tv.tv_sec, (long long)tv.tv_usec);
+ } else {
+ printf("%s failed\n", name[0]);
+ return KSFT_FAIL;
+ }
+
+ return KSFT_PASS;
+}
+
+static int vdso_test_clock_gettime(clockid_t clk_id)
+{
+ /* Find clock_gettime. */
+ vdso_clock_gettime_t vdso_clock_gettime =
+ (vdso_clock_gettime_t)vdso_sym(version, name[1]);
+
+ if (!vdso_clock_gettime) {
+ printf("Could not find %s\n", name[1]);
+ return KSFT_SKIP;
+ }
+
+ struct timespec ts;
+ long ret = vdso_clock_gettime(clk_id, &ts);
+
+ if (ret == 0) {
+ printf("The time is %lld.%06lld\n",
+ (long long)ts.tv_sec, (long long)ts.tv_nsec);
+ } else {
+ printf("%s failed\n", name[1]);
+ return KSFT_FAIL;
+ }
+
+ return KSFT_PASS;
+}
+
+static int vdso_test_time(void)
+{
+ /* Find time. */
+ vdso_time_t vdso_time =
+ (vdso_time_t)vdso_sym(version, name[2]);
+
+ if (!vdso_time) {
+ printf("Could not find %s\n", name[2]);
+ return KSFT_SKIP;
+ }
+
+ long ret = vdso_time(NULL);
+
+ if (ret > 0) {
+ printf("The time in hours since January 1, 1970 is %lld\n",
+ (long long)(ret / 3600));
+ } else {
+ printf("%s failed\n", name[2]);
+ return KSFT_FAIL;
+ }
+
+ return KSFT_PASS;
+}
+
+static int vdso_test_clock_getres(clockid_t clk_id)
+{
+ /* Find clock_getres. */
+ vdso_clock_getres_t vdso_clock_getres =
+ (vdso_clock_getres_t)vdso_sym(version, name[3]);
+
+ if (!vdso_clock_getres) {
+ printf("Could not find %s\n", name[3]);
+ return KSFT_SKIP;
+ }
+
+ struct timespec ts, sys_ts;
+ long ret = vdso_clock_getres(clk_id, &ts);
+
+ if (ret == 0) {
+ printf("The resolution is %lld %lld\n",
+ (long long)ts.tv_sec, (long long)ts.tv_nsec);
+ } else {
+ printf("%s failed\n", name[3]);
+ return KSFT_FAIL;
+ }
+
+ ret = syscall(SYS_clock_getres, clk_id, &sys_ts);
+
+ if ((sys_ts.tv_sec != ts.tv_sec) || (sys_ts.tv_nsec != ts.tv_nsec)) {
+ printf("%s failed\n", name[3]);
+ return KSFT_FAIL;
+ }
+
+ return KSFT_PASS;
+}
+
+const char *vdso_clock_name[12] = {
+ "CLOCK_REALTIME",
+ "CLOCK_MONOTONIC",
+ "CLOCK_PROCESS_CPUTIME_ID",
+ "CLOCK_THREAD_CPUTIME_ID",
+ "CLOCK_MONOTONIC_RAW",
+ "CLOCK_REALTIME_COARSE",
+ "CLOCK_MONOTONIC_COARSE",
+ "CLOCK_BOOTTIME",
+ "CLOCK_REALTIME_ALARM",
+ "CLOCK_BOOTTIME_ALARM",
+ "CLOCK_SGI_CYCLE",
+ "CLOCK_TAI",
+};
+
+/*
+ * This function calls vdso_test_clock_gettime and vdso_test_clock_getres
+ * with different values for clock_id.
+ */
+static inline int vdso_test_clock(clockid_t clock_id)
+{
+ int ret0, ret1;
+
+ ret0 = vdso_test_clock_gettime(clock_id);
+ /* A skipped test is considered passed */
+ if (ret0 == KSFT_SKIP)
+ ret0 = KSFT_PASS;
+
+ ret1 = vdso_test_clock_getres(clock_id);
+ /* A skipped test is considered passed */
+ if (ret1 == KSFT_SKIP)
+ ret1 = KSFT_PASS;
+
+ ret0 += ret1;
+
+ printf("clock_id: %s", vdso_clock_name[clock_id]);
+
+ if (ret0 > 0)
+ printf(" [FAIL]\n");
+ else
+ printf(" [PASS]\n");
+
+ return ret0;
+}
+
+int main(int argc, char **argv)
+{
+ unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
+ int ret;
+
+ if (!sysinfo_ehdr) {
+ printf("AT_SYSINFO_EHDR is not present!\n");
+ return KSFT_SKIP;
+ }
+
+ vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR));
+
+ ret = vdso_test_gettimeofday();
+
+#if _POSIX_TIMERS > 0
+
+#ifdef CLOCK_REALTIME
+ ret += vdso_test_clock(CLOCK_REALTIME);
+#endif
+
+#ifdef CLOCK_BOOTTIME
+ ret += vdso_test_clock(CLOCK_BOOTTIME);
+#endif
+
+#ifdef CLOCK_TAI
+ ret += vdso_test_clock(CLOCK_TAI);
+#endif
+
+#ifdef CLOCK_REALTIME_COARSE
+ ret += vdso_test_clock(CLOCK_REALTIME_COARSE);
+#endif
+
+#ifdef CLOCK_MONOTONIC
+ ret += vdso_test_clock(CLOCK_MONOTONIC);
+#endif
+
+#ifdef CLOCK_MONOTONIC_RAW
+ ret += vdso_test_clock(CLOCK_MONOTONIC_RAW);
+#endif
+
+#ifdef CLOCK_MONOTONIC_COARSE
+ ret += vdso_test_clock(CLOCK_MONOTONIC_COARSE);
+#endif
+
+#endif
+
+ ret += vdso_test_time();
+
+ if (ret > 0)
+ return KSFT_FAIL;
+
+ return KSFT_PASS;
+}
--
2.21.0