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 17 const char *version = "LINUX_2.6"; 18 const char *name = "__vdso_getcpu"; 19 20 struct getcpu_cache; 21 typedef long (*getcpu_t)(unsigned int *, unsigned int *, 22 struct getcpu_cache *); 23 24 int main(int argc, char **argv) 25 { 26 unsigned long sysinfo_ehdr; 27 unsigned int cpu, node; 28 getcpu_t get_cpu; 29 long ret; 30 31 sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR); 32 if (!sysinfo_ehdr) { 33 printf("AT_SYSINFO_EHDR is not present!\n"); 34 return KSFT_SKIP; 35 } 36 37 vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR)); 38 39 get_cpu = (getcpu_t)vdso_sym(version, name); 40 if (!get_cpu) { 41 printf("Could not find %s\n", name); 42 return KSFT_SKIP; 43 } 44 45 ret = get_cpu(&cpu, &node, 0); 46 if (ret == 0) { 47 printf("Running on CPU %u node %u\n", cpu, node); 48 } else { 49 printf("%s failed\n", name); 50 return KSFT_FAIL; 51 } 52 53 return 0; 54 } 55