18c2ecf20Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0 28c2ecf20Sopenharmony_ci/* 38c2ecf20Sopenharmony_ci * Tests for prctl(PR_GET_TSC, ...) / prctl(PR_SET_TSC, ...) 48c2ecf20Sopenharmony_ci * 58c2ecf20Sopenharmony_ci * Basic test to test behaviour of PR_GET_TSC and PR_SET_TSC 68c2ecf20Sopenharmony_ci */ 78c2ecf20Sopenharmony_ci 88c2ecf20Sopenharmony_ci#include <stdio.h> 98c2ecf20Sopenharmony_ci#include <stdlib.h> 108c2ecf20Sopenharmony_ci#include <unistd.h> 118c2ecf20Sopenharmony_ci#include <signal.h> 128c2ecf20Sopenharmony_ci#include <inttypes.h> 138c2ecf20Sopenharmony_ci 148c2ecf20Sopenharmony_ci 158c2ecf20Sopenharmony_ci#include <sys/prctl.h> 168c2ecf20Sopenharmony_ci#include <linux/prctl.h> 178c2ecf20Sopenharmony_ci 188c2ecf20Sopenharmony_ci/* Get/set the process' ability to use the timestamp counter instruction */ 198c2ecf20Sopenharmony_ci#ifndef PR_GET_TSC 208c2ecf20Sopenharmony_ci#define PR_GET_TSC 25 218c2ecf20Sopenharmony_ci#define PR_SET_TSC 26 228c2ecf20Sopenharmony_ci# define PR_TSC_ENABLE 1 /* allow the use of the timestamp counter */ 238c2ecf20Sopenharmony_ci# define PR_TSC_SIGSEGV 2 /* throw a SIGSEGV instead of reading the TSC */ 248c2ecf20Sopenharmony_ci#endif 258c2ecf20Sopenharmony_ci 268c2ecf20Sopenharmony_ciconst char *tsc_names[] = 278c2ecf20Sopenharmony_ci{ 288c2ecf20Sopenharmony_ci [0] = "[not set]", 298c2ecf20Sopenharmony_ci [PR_TSC_ENABLE] = "PR_TSC_ENABLE", 308c2ecf20Sopenharmony_ci [PR_TSC_SIGSEGV] = "PR_TSC_SIGSEGV", 318c2ecf20Sopenharmony_ci}; 328c2ecf20Sopenharmony_ci 338c2ecf20Sopenharmony_cistatic uint64_t rdtsc(void) 348c2ecf20Sopenharmony_ci{ 358c2ecf20Sopenharmony_ciuint32_t lo, hi; 368c2ecf20Sopenharmony_ci/* We cannot use "=A", since this would use %rax on x86_64 */ 378c2ecf20Sopenharmony_ci__asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi)); 388c2ecf20Sopenharmony_cireturn (uint64_t)hi << 32 | lo; 398c2ecf20Sopenharmony_ci} 408c2ecf20Sopenharmony_ci 418c2ecf20Sopenharmony_cistatic void sigsegv_cb(int sig) 428c2ecf20Sopenharmony_ci{ 438c2ecf20Sopenharmony_ci int tsc_val = 0; 448c2ecf20Sopenharmony_ci 458c2ecf20Sopenharmony_ci printf("[ SIG_SEGV ]\n"); 468c2ecf20Sopenharmony_ci printf("prctl(PR_GET_TSC, &tsc_val); "); 478c2ecf20Sopenharmony_ci fflush(stdout); 488c2ecf20Sopenharmony_ci 498c2ecf20Sopenharmony_ci if ( prctl(PR_GET_TSC, &tsc_val) == -1) 508c2ecf20Sopenharmony_ci perror("prctl"); 518c2ecf20Sopenharmony_ci 528c2ecf20Sopenharmony_ci printf("tsc_val == %s\n", tsc_names[tsc_val]); 538c2ecf20Sopenharmony_ci printf("prctl(PR_SET_TSC, PR_TSC_ENABLE)\n"); 548c2ecf20Sopenharmony_ci fflush(stdout); 558c2ecf20Sopenharmony_ci if ( prctl(PR_SET_TSC, PR_TSC_ENABLE) == -1) 568c2ecf20Sopenharmony_ci perror("prctl"); 578c2ecf20Sopenharmony_ci 588c2ecf20Sopenharmony_ci printf("rdtsc() == "); 598c2ecf20Sopenharmony_ci} 608c2ecf20Sopenharmony_ci 618c2ecf20Sopenharmony_ciint main(void) 628c2ecf20Sopenharmony_ci{ 638c2ecf20Sopenharmony_ci int tsc_val = 0; 648c2ecf20Sopenharmony_ci 658c2ecf20Sopenharmony_ci signal(SIGSEGV, sigsegv_cb); 668c2ecf20Sopenharmony_ci 678c2ecf20Sopenharmony_ci printf("rdtsc() == %llu\n", (unsigned long long)rdtsc()); 688c2ecf20Sopenharmony_ci printf("prctl(PR_GET_TSC, &tsc_val); "); 698c2ecf20Sopenharmony_ci fflush(stdout); 708c2ecf20Sopenharmony_ci 718c2ecf20Sopenharmony_ci if ( prctl(PR_GET_TSC, &tsc_val) == -1) 728c2ecf20Sopenharmony_ci perror("prctl"); 738c2ecf20Sopenharmony_ci 748c2ecf20Sopenharmony_ci printf("tsc_val == %s\n", tsc_names[tsc_val]); 758c2ecf20Sopenharmony_ci printf("rdtsc() == %llu\n", (unsigned long long)rdtsc()); 768c2ecf20Sopenharmony_ci printf("prctl(PR_SET_TSC, PR_TSC_ENABLE)\n"); 778c2ecf20Sopenharmony_ci fflush(stdout); 788c2ecf20Sopenharmony_ci 798c2ecf20Sopenharmony_ci if ( prctl(PR_SET_TSC, PR_TSC_ENABLE) == -1) 808c2ecf20Sopenharmony_ci perror("prctl"); 818c2ecf20Sopenharmony_ci 828c2ecf20Sopenharmony_ci printf("rdtsc() == %llu\n", (unsigned long long)rdtsc()); 838c2ecf20Sopenharmony_ci printf("prctl(PR_SET_TSC, PR_TSC_SIGSEGV)\n"); 848c2ecf20Sopenharmony_ci fflush(stdout); 858c2ecf20Sopenharmony_ci 868c2ecf20Sopenharmony_ci if ( prctl(PR_SET_TSC, PR_TSC_SIGSEGV) == -1) 878c2ecf20Sopenharmony_ci perror("prctl"); 888c2ecf20Sopenharmony_ci 898c2ecf20Sopenharmony_ci printf("rdtsc() == "); 908c2ecf20Sopenharmony_ci fflush(stdout); 918c2ecf20Sopenharmony_ci printf("%llu\n", (unsigned long long)rdtsc()); 928c2ecf20Sopenharmony_ci fflush(stdout); 938c2ecf20Sopenharmony_ci 948c2ecf20Sopenharmony_ci exit(EXIT_SUCCESS); 958c2ecf20Sopenharmony_ci} 968c2ecf20Sopenharmony_ci 97