vdso_test_getcpu.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * vdso_test_getcpu.c: Sample code to test parse_vdso.c and vDSO getcpu()
 4 *
 5 * Copyright (c) 2020 Arm Ltd
 6 */
 7
 8#include <stdint.h>
 9#include <elf.h>
10#include <stdio.h>
11#include <sys/auxv.h>
12#include <sys/time.h>
13
14#include "kselftest.h"
15#include "parse_vdso.h"
16#include "vdso_config.h"
17#include "vdso_call.h"
18
19struct getcpu_cache;
20typedef long (*getcpu_t)(unsigned int *, unsigned int *,
21			 struct getcpu_cache *);
22
23int main(int argc, char **argv)
24{
25	const char *version = versions[VDSO_VERSION];
26	const char **name = (const char **)&names[VDSO_NAMES];
27	unsigned long sysinfo_ehdr;
28	unsigned int cpu, node;
29	getcpu_t get_cpu;
30	long ret;
31
32	sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
33	if (!sysinfo_ehdr) {
34		printf("AT_SYSINFO_EHDR is not present!\n");
35		return KSFT_SKIP;
36	}
37
38	vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR));
39
40	get_cpu = (getcpu_t)vdso_sym(version, name[4]);
41	if (!get_cpu) {
42		printf("Could not find %s\n", name[4]);
43		return KSFT_SKIP;
44	}
45
46	ret = VDSO_CALL(get_cpu, 3, &cpu, &node, 0);
47	if (ret == 0) {
48		printf("Running on CPU %u node %u\n", cpu, node);
49	} else {
50		printf("%s failed\n", name[4]);
51		return KSFT_FAIL;
52	}
53
54	return 0;
55}