1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * vdso_test_gettimeofday.c: Sample code to test parse_vdso.c and
4*4882a593Smuzhiyun * vDSO gettimeofday()
5*4882a593Smuzhiyun * Copyright (c) 2014 Andy Lutomirski
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Compile with:
8*4882a593Smuzhiyun * gcc -std=gnu99 vdso_test_gettimeofday.c parse_vdso_gettimeofday.c
9*4882a593Smuzhiyun *
10*4882a593Smuzhiyun * Tested on x86, 32-bit and 64-bit. It may work on other architectures, too.
11*4882a593Smuzhiyun */
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun #include <stdint.h>
14*4882a593Smuzhiyun #include <elf.h>
15*4882a593Smuzhiyun #include <stdio.h>
16*4882a593Smuzhiyun #include <sys/auxv.h>
17*4882a593Smuzhiyun #include <sys/time.h>
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun #include "../kselftest.h"
20*4882a593Smuzhiyun #include "parse_vdso.h"
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun /*
23*4882a593Smuzhiyun * ARM64's vDSO exports its gettimeofday() implementation with a different
24*4882a593Smuzhiyun * name and version from other architectures, so we need to handle it as
25*4882a593Smuzhiyun * a special case.
26*4882a593Smuzhiyun */
27*4882a593Smuzhiyun #if defined(__aarch64__)
28*4882a593Smuzhiyun const char *version = "LINUX_2.6.39";
29*4882a593Smuzhiyun const char *name = "__kernel_gettimeofday";
30*4882a593Smuzhiyun #else
31*4882a593Smuzhiyun const char *version = "LINUX_2.6";
32*4882a593Smuzhiyun const char *name = "__vdso_gettimeofday";
33*4882a593Smuzhiyun #endif
34*4882a593Smuzhiyun
main(int argc,char ** argv)35*4882a593Smuzhiyun int main(int argc, char **argv)
36*4882a593Smuzhiyun {
37*4882a593Smuzhiyun unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
38*4882a593Smuzhiyun if (!sysinfo_ehdr) {
39*4882a593Smuzhiyun printf("AT_SYSINFO_EHDR is not present!\n");
40*4882a593Smuzhiyun return KSFT_SKIP;
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR));
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun /* Find gettimeofday. */
46*4882a593Smuzhiyun typedef long (*gtod_t)(struct timeval *tv, struct timezone *tz);
47*4882a593Smuzhiyun gtod_t gtod = (gtod_t)vdso_sym(version, name);
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun if (!gtod) {
50*4882a593Smuzhiyun printf("Could not find %s\n", name);
51*4882a593Smuzhiyun return KSFT_SKIP;
52*4882a593Smuzhiyun }
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun struct timeval tv;
55*4882a593Smuzhiyun long ret = gtod(&tv, 0);
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun if (ret == 0) {
58*4882a593Smuzhiyun printf("The time is %lld.%06lld\n",
59*4882a593Smuzhiyun (long long)tv.tv_sec, (long long)tv.tv_usec);
60*4882a593Smuzhiyun } else {
61*4882a593Smuzhiyun printf("%s failed\n", name);
62*4882a593Smuzhiyun return KSFT_FAIL;
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun return 0;
66*4882a593Smuzhiyun }
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