1 /* 2 * Copyright 2016, Anton Blanchard, Michael Ellerman, IBM Corp. 3 * Licensed under GPLv2. 4 */ 5 6 #define _GNU_SOURCE 7 8 #include <stdio.h> 9 #include <sys/syscall.h> 10 #include <time.h> 11 #include <unistd.h> 12 #include <linux/futex.h> 13 14 #include "utils.h" 15 16 #define ITERATIONS 100000000 17 18 #define futex(A, B, C, D, E, F) syscall(__NR_futex, A, B, C, D, E, F) 19 20 int test_futex(void) 21 { 22 struct timespec ts_start, ts_end; 23 unsigned long i = ITERATIONS; 24 25 clock_gettime(CLOCK_MONOTONIC, &ts_start); 26 27 while (i--) { 28 unsigned int addr = 0; 29 futex(&addr, FUTEX_WAKE, 1, NULL, NULL, 0); 30 } 31 32 clock_gettime(CLOCK_MONOTONIC, &ts_end); 33 34 printf("time = %.6f\n", ts_end.tv_sec - ts_start.tv_sec + (ts_end.tv_nsec - ts_start.tv_nsec) / 1e9); 35 36 return 0; 37 } 38 39 int main(void) 40 { 41 return test_harness(test_futex, "futex_bench"); 42 } 43
