/* * Copyright 2016, Anton Blanchard, Michael Ellerman, IBM Corp. * Licensed under GPLv2. */ #define _GNU_SOURCE #include <stdio.h> #include <sys/syscall.h> #include <time.h> #include <unistd.h> #include <linux/futex.h> #include "utils.h" #define ITERATIONS 100000000 #define futex(A, B, C, D, E, F) syscall(__NR_futex, A, B, C, D, E, F) int test_futex(void) { struct timespec ts_start, ts_end; unsigned long i = ITERATIONS; clock_gettime(CLOCK_MONOTONIC, &ts_start); while (i--) { unsigned int addr = 0; futex(&addr, FUTEX_WAKE, 1, NULL, NULL, 0); } clock_gettime(CLOCK_MONOTONIC, &ts_end); printf("time = %.6f\n", ts_end.tv_sec - ts_start.tv_sec + (ts_end.tv_nsec - ts_start.tv_nsec) / 1e9); return 0; } int main(void) { test_harness_set_timeout(300); return test_harness(test_futex, "futex_bench"); }