1 // timer.cc -- helper class for time accounting 2 3 // Copyright (C) 2009-2016 Free Software Foundation, Inc. 4 // Written by Rafael Avila de Espindola <espindola (at) google.com>. 5 6 // This file is part of gold. 7 8 // This program is free software; you can redistribute it and/or modify 9 // it under the terms of the GNU General Public License as published by 10 // the Free Software Foundation; either version 3 of the License, or 11 // (at your option) any later version. 12 13 // This program is distributed in the hope that it will be useful, 14 // but WITHOUT ANY WARRANTY; without even the implied warranty of 15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 // GNU General Public License for more details. 17 18 // You should have received a copy of the GNU General Public License 19 // along with this program; if not, write to the Free Software 20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 // MA 02110-1301, USA. 22 23 #include "gold.h" 24 25 #include <unistd.h> 26 27 #ifdef HAVE_TIMES 28 #include <sys/times.h> 29 #endif 30 31 #include "libiberty.h" 32 33 #include "timer.h" 34 35 namespace gold 36 { 37 38 // Class Timer 39 40 Timer::Timer() 41 { 42 this->start_time_.wall = 0; 43 this->start_time_.user = 0; 44 this->start_time_.sys = 0; 45 } 46 47 // Start counting the time. 48 void 49 Timer::start() 50 { 51 this->get_time(&this->start_time_); 52 } 53 54 // Record the time used by pass N (0 <= N <= 2). 55 void 56 Timer::stamp(int n) 57 { 58 gold_assert(n >= 0 && n <= 2); 59 TimeStats& thispass = this->pass_times_[n]; 60 this->get_time(&thispass); 61 } 62 63 #if HAVE_SYSCONF && defined _SC_CLK_TCK 64 # define TICKS_PER_SECOND sysconf (_SC_CLK_TCK) /* POSIX 1003.1-1996 */ 65 #else 66 # ifdef CLK_TCK 67 # define TICKS_PER_SECOND CLK_TCK /* POSIX 1003.1-1988; obsolescent */ 68 # else 69 # ifdef HZ 70 # define TICKS_PER_SECOND HZ /* traditional UNIX */ 71 # else 72 # define TICKS_PER_SECOND 100 /* often the correct value */ 73 # endif 74 # endif 75 #endif 76 77 // times returns statistics in clock_t units. This variable will hold the 78 // conversion factor to seconds. We use a variable that is initialized once 79 // because sysconf can be slow. 80 static long ticks_per_sec; 81 class Timer_init 82 { 83 public: 84 Timer_init() 85 { 86 ticks_per_sec = TICKS_PER_SECOND; 87 } 88 }; 89 Timer_init timer_init; 90 91 // Write the current time information. 92 void 93 Timer::get_time(TimeStats *now) 94 { 95 #ifdef HAVE_TIMES 96 tms t; 97 now->wall = (times(&t) * 1000) / ticks_per_sec; 98 now->user = (t.tms_utime * 1000) / ticks_per_sec; 99 now->sys = (t.tms_stime * 1000) / ticks_per_sec; 100 #else 101 now->wall = get_run_time() / 1000; 102 now->user = 0; 103 now->sys = 0; 104 #endif 105 } 106 107 // Return the stats since start was called. 108 Timer::TimeStats 109 Timer::get_elapsed_time() 110 { 111 TimeStats now; 112 this->get_time(&now); 113 TimeStats delta; 114 delta.wall = now.wall - this->start_time_.wall; 115 delta.user = now.user - this->start_time_.user; 116 delta.sys = now.sys - this->start_time_.sys; 117 return delta; 118 } 119 120 // Return the stats for pass N (0 <= N <= 2). 121 Timer::TimeStats 122 Timer::get_pass_time(int n) 123 { 124 gold_assert(n >= 0 && n <= 2); 125 TimeStats thispass = this->pass_times_[n]; 126 TimeStats& lastpass = n > 0 ? this->pass_times_[n-1] : this->start_time_; 127 thispass.wall -= lastpass.wall; 128 thispass.user -= lastpass.user; 129 thispass.sys -= lastpass.sys; 130 return thispass; 131 } 132 133 } 134
