1 /* 2 * QEMU System Emulator 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #include "qemu/osdep.h" 25 #include "qemu/timer.h" 26 27 /***********************************************************/ 28 /* real time host monotonic timer */ 29 30 #ifdef _WIN32 31 32 int64_t clock_freq; 33 34 static void __attribute__((constructor)) init_get_clock(void) 35 { 36 LARGE_INTEGER freq; 37 int ret; 38 ret = QueryPerformanceFrequency(&freq); 39 if (ret == 0) { 40 fprintf(stderr, "Could not calibrate ticks\n"); 41 exit(1); 42 } 43 clock_freq = freq.QuadPart; 44 } 45 46 #else 47 48 int use_rt_clock; 49 50 static void __attribute__((constructor)) init_get_clock(void) 51 { 52 struct timespec ts; 53 54 use_rt_clock = 0; 55 if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0) { 56 use_rt_clock = 1; 57 } 58 } 59 #endif 60