/* Skeleton for benchmark programs. Copyright (C) 2013 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see . */ #include #include #include #include #include int main (int argc, char **argv) { unsigned long i, j, k; uint64_t total = 0, max = 0, min = 0x7fffffffffffffff; struct timespec start, end; memset (&start, 0, sizeof (start)); memset (&end, 0, sizeof (end)); clock_getres (CLOCK_PROCESS_CPUTIME_ID, &start); /* Measure 1000 times the resolution of the clock. So for a 1ns resolution clock, we measure 1000 iterations of the function call at a time. Measurements close to the minimum clock resolution won't make much sense, but it's better than having nothing at all. */ unsigned long iters = 1000 * start.tv_nsec; unsigned long total_iters = ITER / iters; for (i = 0; i < NUM_SAMPLES; i++) { for (j = 0; j < total_iters; j ++) { clock_gettime (CLOCK_PROCESS_CPUTIME_ID, &start); for (k = 0; k < iters; k++) BENCH_FUNC(i); clock_gettime (CLOCK_PROCESS_CPUTIME_ID, &end); uint64_t cur = (end.tv_nsec - start.tv_nsec + ((end.tv_sec - start.tv_sec) * (uint64_t) 1000000000)); if (cur > max) max = cur; if (cur < min) min = cur; total += cur; } } double d_total_s = total * 1e-9; double d_iters = iters; double d_total_i = (double)ITER * NUM_SAMPLES; printf (FUNCNAME ": ITERS:%g: TOTAL:%gs, MAX:%gns, MIN:%gns, %g iter/s\n", d_total_i, d_total_s, max / d_iters, min / d_iters, d_total_i / d_total_s); return 0; }