kselftest: Extend vDSO selftest

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 <[e-mail]>
Signed-off-by: Vincenzo Frascino <[e-mail]>
Acked-by: Thomas Gleixner <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

tools/testing/selftests/vDSO/Makefile

···
 ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
 
 TEST_GEN_PROGS := $(OUTPUT)/vdso_test_gettimeofday $(OUTPUT)/vdso_test_getcpu
+TEST_GEN_PROGS += $(OUTPUT)/vdso_test_abi
 ifeq ($(ARCH),x86)
 TEST_GEN_PROGS += $(OUTPUT)/vdso_standalone_test_x86
 endif
···
 all: $(TEST_GEN_PROGS)
 $(OUTPUT)/vdso_test_gettimeofday: parse_vdso.c vdso_test_gettimeofday.c
 $(OUTPUT)/vdso_test_getcpu: parse_vdso.c vdso_test_getcpu.c
+$(OUTPUT)/vdso_test_abi: parse_vdso.c vdso_test_abi.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 \

tools/testing/selftests/vDSO/vdso_config.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * vdso_config.h: Configuration options for vDSO tests.
+ * Copyright (c) 2019 Arm Ltd.
+ */
+#ifndef __VDSO_CONFIG_H__
+#define __VDSO_CONFIG_H__
+
+/*
+ * Each architecture exports its vDSO implementation with different names
+ * and a different version from the others, so we need to handle it as a
+ * special case.
+ */
+#if defined(__arm__)
+#define VDSO_VERSION		0
+#define VDSO_NAMES		1
+#define VDSO_32BIT		1
+#elif defined(__aarch64__)
+#define VDSO_VERSION		3
+#define VDSO_NAMES		0
+#elif defined(__powerpc__)
+#define VDSO_VERSION		1
+#define VDSO_NAMES		0
+#define VDSO_32BIT		1
+#elif defined(__powerpc64__)
+#define VDSO_VERSION		1
+#define VDSO_NAMES		0
+#elif defined (__s390__)
+#define VDSO_VERSION		2
+#define VDSO_NAMES		0
+#define VDSO_32BIT		1
+#elif defined (__s390X__)
+#define VDSO_VERSION		2
+#define VDSO_NAMES		0
+#elif defined(__mips__)
+#define VDSO_VERSION		0
+#define VDSO_NAMES		1
+#define VDSO_32BIT		1
+#elif defined(__sparc__)
+#define VDSO_VERSION		0
+#define VDSO_NAMES		1
+#define VDSO_32BIT		1
+#elif defined(__i386__)
+#define VDSO_VERSION		0
+#define VDSO_NAMES		1
+#define VDSO_32BIT		1
+#elif defined(__x86_64__)
+#define VDSO_VERSION		0
+#define VDSO_NAMES		1
+#elif defined(__riscv__)
+#define VDSO_VERSION		5
+#define VDSO_NAMES		1
+#define VDSO_32BIT		1
+#else /* nds32 */
+#define VDSO_VERSION		4
+#define VDSO_NAMES		1
+#define VDSO_32BIT		1
+#endif
+
+static const char *versions[6] = {
+	"LINUX_2.6",
+	"LINUX_2.6.15",
+	"LINUX_2.6.29",
+	"LINUX_2.6.39",
+	"LINUX_4",
+	"LINUX_4.15",
+};
+
+static const char *names[2][5] = {
+	{
+		"__kernel_gettimeofday",
+		"__kernel_clock_gettime",
+		"__kernel_time",
+		"__kernel_clock_getres",
+#if defined(VDSO_32BIT)
+		"__kernel_clock_gettime64",
+#endif
+	},
+	{
+		"__vdso_gettimeofday",
+		"__vdso_clock_gettime",
+		"__vdso_time",
+		"__vdso_clock_getres",
+#if defined(VDSO_32BIT)
+		"__vdso_clock_gettime64",
+#endif
+	},
+};
+
+#endif /* __VDSO_CONFIG_H__ */

tools/testing/selftests/vDSO/vdso_test_abi.c

···
+// 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
+ *
+ */
+
+#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"
+#include "vdso_config.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);
+
+static const char *version;
+static const char **name;
+
+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;
+	}
+
+	version = versions[VDSO_VERSION];
+	name = (const char **)&names[VDSO_NAMES];
+
+	printf("[vDSO kselftest] VDSO_VERSION: %s\n", version);
+
+	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;
+}