subr_time.c revision 1.1.2.2
1 1.1.2.2 skrll /* $NetBSD: subr_time.c,v 1.1.2.2 2007/08/15 13:49:15 skrll Exp $ */ 2 1.1.2.2 skrll 3 1.1.2.2 skrll /* 4 1.1.2.2 skrll * Copyright (c) 1982, 1986, 1989, 1993 5 1.1.2.2 skrll * The Regents of the University of California. All rights reserved. 6 1.1.2.2 skrll * 7 1.1.2.2 skrll * Redistribution and use in source and binary forms, with or without 8 1.1.2.2 skrll * modification, are permitted provided that the following conditions 9 1.1.2.2 skrll * are met: 10 1.1.2.2 skrll * 1. Redistributions of source code must retain the above copyright 11 1.1.2.2 skrll * notice, this list of conditions and the following disclaimer. 12 1.1.2.2 skrll * 2. Redistributions in binary form must reproduce the above copyright 13 1.1.2.2 skrll * notice, this list of conditions and the following disclaimer in the 14 1.1.2.2 skrll * documentation and/or other materials provided with the distribution. 15 1.1.2.2 skrll * 3. Neither the name of the University nor the names of its contributors 16 1.1.2.2 skrll * may be used to endorse or promote products derived from this software 17 1.1.2.2 skrll * without specific prior written permission. 18 1.1.2.2 skrll * 19 1.1.2.2 skrll * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 1.1.2.2 skrll * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 1.1.2.2 skrll * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 1.1.2.2 skrll * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 1.1.2.2 skrll * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 1.1.2.2 skrll * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 1.1.2.2 skrll * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 1.1.2.2 skrll * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 1.1.2.2 skrll * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 1.1.2.2 skrll * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 1.1.2.2 skrll * SUCH DAMAGE. 30 1.1.2.2 skrll * 31 1.1.2.2 skrll * @(#)kern_clock.c 8.5 (Berkeley) 1/21/94 32 1.1.2.2 skrll * @(#)kern_time.c 8.4 (Berkeley) 5/26/95 33 1.1.2.2 skrll */ 34 1.1.2.2 skrll 35 1.1.2.2 skrll #include <sys/cdefs.h> 36 1.1.2.2 skrll __KERNEL_RCSID(0, "$NetBSD: subr_time.c,v 1.1.2.2 2007/08/15 13:49:15 skrll Exp $"); 37 1.1.2.2 skrll 38 1.1.2.2 skrll #include <sys/param.h> 39 1.1.2.2 skrll #include <sys/kernel.h> 40 1.1.2.2 skrll #include <sys/timex.h> 41 1.1.2.2 skrll #include <sys/time.h> 42 1.1.2.2 skrll #include <sys/timetc.h> 43 1.1.2.2 skrll 44 1.1.2.2 skrll #ifdef __HAVE_TIMECOUNTER 45 1.1.2.2 skrll /* 46 1.1.2.2 skrll * Compute number of hz until specified time. Used to compute second 47 1.1.2.2 skrll * argument to callout_reset() from an absolute time. 48 1.1.2.2 skrll */ 49 1.1.2.2 skrll int 50 1.1.2.2 skrll hzto(struct timeval *tvp) 51 1.1.2.2 skrll { 52 1.1.2.2 skrll struct timeval now, tv; 53 1.1.2.2 skrll 54 1.1.2.2 skrll tv = *tvp; /* Don't modify original tvp. */ 55 1.1.2.2 skrll getmicrotime(&now); 56 1.1.2.2 skrll timersub(&tv, &now, &tv); 57 1.1.2.2 skrll return tvtohz(&tv); 58 1.1.2.2 skrll } 59 1.1.2.2 skrll #endif /* __HAVE_TIMECOUNTER */ 60 1.1.2.2 skrll 61 1.1.2.2 skrll /* 62 1.1.2.2 skrll * Compute number of ticks in the specified amount of time. 63 1.1.2.2 skrll */ 64 1.1.2.2 skrll int 65 1.1.2.2 skrll tvtohz(struct timeval *tv) 66 1.1.2.2 skrll { 67 1.1.2.2 skrll unsigned long ticks; 68 1.1.2.2 skrll long sec, usec; 69 1.1.2.2 skrll 70 1.1.2.2 skrll /* 71 1.1.2.2 skrll * If the number of usecs in the whole seconds part of the time 72 1.1.2.2 skrll * difference fits in a long, then the total number of usecs will 73 1.1.2.2 skrll * fit in an unsigned long. Compute the total and convert it to 74 1.1.2.2 skrll * ticks, rounding up and adding 1 to allow for the current tick 75 1.1.2.2 skrll * to expire. Rounding also depends on unsigned long arithmetic 76 1.1.2.2 skrll * to avoid overflow. 77 1.1.2.2 skrll * 78 1.1.2.2 skrll * Otherwise, if the number of ticks in the whole seconds part of 79 1.1.2.2 skrll * the time difference fits in a long, then convert the parts to 80 1.1.2.2 skrll * ticks separately and add, using similar rounding methods and 81 1.1.2.2 skrll * overflow avoidance. This method would work in the previous 82 1.1.2.2 skrll * case, but it is slightly slower and assumes that hz is integral. 83 1.1.2.2 skrll * 84 1.1.2.2 skrll * Otherwise, round the time difference down to the maximum 85 1.1.2.2 skrll * representable value. 86 1.1.2.2 skrll * 87 1.1.2.2 skrll * If ints are 32-bit, then the maximum value for any timeout in 88 1.1.2.2 skrll * 10ms ticks is 248 days. 89 1.1.2.2 skrll */ 90 1.1.2.2 skrll sec = tv->tv_sec; 91 1.1.2.2 skrll usec = tv->tv_usec; 92 1.1.2.2 skrll 93 1.1.2.2 skrll if (usec < 0) { 94 1.1.2.2 skrll sec--; 95 1.1.2.2 skrll usec += 1000000; 96 1.1.2.2 skrll } 97 1.1.2.2 skrll 98 1.1.2.2 skrll if (sec < 0 || (sec == 0 && usec <= 0)) { 99 1.1.2.2 skrll /* 100 1.1.2.2 skrll * Would expire now or in the past. Return 0 ticks. 101 1.1.2.2 skrll * This is different from the legacy hzto() interface, 102 1.1.2.2 skrll * and callers need to check for it. 103 1.1.2.2 skrll */ 104 1.1.2.2 skrll ticks = 0; 105 1.1.2.2 skrll } else if (sec <= (LONG_MAX / 1000000)) 106 1.1.2.2 skrll ticks = (((sec * 1000000) + (unsigned long)usec + (tick - 1)) 107 1.1.2.2 skrll / tick) + 1; 108 1.1.2.2 skrll else if (sec <= (LONG_MAX / hz)) 109 1.1.2.2 skrll ticks = (sec * hz) + 110 1.1.2.2 skrll (((unsigned long)usec + (tick - 1)) / tick) + 1; 111 1.1.2.2 skrll else 112 1.1.2.2 skrll ticks = LONG_MAX; 113 1.1.2.2 skrll 114 1.1.2.2 skrll if (ticks > INT_MAX) 115 1.1.2.2 skrll ticks = INT_MAX; 116 1.1.2.2 skrll 117 1.1.2.2 skrll return ((int)ticks); 118 1.1.2.2 skrll } 119 1.1.2.2 skrll 120 1.1.2.2 skrll #ifndef __HAVE_TIMECOUNTER 121 1.1.2.2 skrll /* 122 1.1.2.2 skrll * Compute number of hz until specified time. Used to compute second 123 1.1.2.2 skrll * argument to callout_reset() from an absolute time. 124 1.1.2.2 skrll */ 125 1.1.2.2 skrll int 126 1.1.2.2 skrll hzto(struct timeval *tv) 127 1.1.2.2 skrll { 128 1.1.2.2 skrll unsigned long ticks; 129 1.1.2.2 skrll long sec, usec; 130 1.1.2.2 skrll int s; 131 1.1.2.2 skrll 132 1.1.2.2 skrll /* 133 1.1.2.2 skrll * If the number of usecs in the whole seconds part of the time 134 1.1.2.2 skrll * difference fits in a long, then the total number of usecs will 135 1.1.2.2 skrll * fit in an unsigned long. Compute the total and convert it to 136 1.1.2.2 skrll * ticks, rounding up and adding 1 to allow for the current tick 137 1.1.2.2 skrll * to expire. Rounding also depends on unsigned long arithmetic 138 1.1.2.2 skrll * to avoid overflow. 139 1.1.2.2 skrll * 140 1.1.2.2 skrll * Otherwise, if the number of ticks in the whole seconds part of 141 1.1.2.2 skrll * the time difference fits in a long, then convert the parts to 142 1.1.2.2 skrll * ticks separately and add, using similar rounding methods and 143 1.1.2.2 skrll * overflow avoidance. This method would work in the previous 144 1.1.2.2 skrll * case, but it is slightly slower and assume that hz is integral. 145 1.1.2.2 skrll * 146 1.1.2.2 skrll * Otherwise, round the time difference down to the maximum 147 1.1.2.2 skrll * representable value. 148 1.1.2.2 skrll * 149 1.1.2.2 skrll * If ints are 32-bit, then the maximum value for any timeout in 150 1.1.2.2 skrll * 10ms ticks is 248 days. 151 1.1.2.2 skrll */ 152 1.1.2.2 skrll s = splclock(); 153 1.1.2.2 skrll sec = tv->tv_sec - time.tv_sec; 154 1.1.2.2 skrll usec = tv->tv_usec - time.tv_usec; 155 1.1.2.2 skrll splx(s); 156 1.1.2.2 skrll 157 1.1.2.2 skrll if (usec < 0) { 158 1.1.2.2 skrll sec--; 159 1.1.2.2 skrll usec += 1000000; 160 1.1.2.2 skrll } 161 1.1.2.2 skrll 162 1.1.2.2 skrll if (sec < 0 || (sec == 0 && usec <= 0)) { 163 1.1.2.2 skrll /* 164 1.1.2.2 skrll * Would expire now or in the past. Return 0 ticks. 165 1.1.2.2 skrll * This is different from the legacy hzto() interface, 166 1.1.2.2 skrll * and callers need to check for it. 167 1.1.2.2 skrll */ 168 1.1.2.2 skrll ticks = 0; 169 1.1.2.2 skrll } else if (sec <= (LONG_MAX / 1000000)) 170 1.1.2.2 skrll ticks = (((sec * 1000000) + (unsigned long)usec + (tick - 1)) 171 1.1.2.2 skrll / tick) + 1; 172 1.1.2.2 skrll else if (sec <= (LONG_MAX / hz)) 173 1.1.2.2 skrll ticks = (sec * hz) + 174 1.1.2.2 skrll (((unsigned long)usec + (tick - 1)) / tick) + 1; 175 1.1.2.2 skrll else 176 1.1.2.2 skrll ticks = LONG_MAX; 177 1.1.2.2 skrll 178 1.1.2.2 skrll if (ticks > INT_MAX) 179 1.1.2.2 skrll ticks = INT_MAX; 180 1.1.2.2 skrll 181 1.1.2.2 skrll return ((int)ticks); 182 1.1.2.2 skrll } 183 1.1.2.2 skrll #endif /* !__HAVE_TIMECOUNTER */ 184 1.1.2.2 skrll 185 1.1.2.2 skrll /* 186 1.1.2.2 skrll * Compute number of ticks in the specified amount of time. 187 1.1.2.2 skrll */ 188 1.1.2.2 skrll int 189 1.1.2.2 skrll tstohz(struct timespec *ts) 190 1.1.2.2 skrll { 191 1.1.2.2 skrll struct timeval tv; 192 1.1.2.2 skrll 193 1.1.2.2 skrll /* 194 1.1.2.2 skrll * usec has great enough resolution for hz, so convert to a 195 1.1.2.2 skrll * timeval and use tvtohz() above. 196 1.1.2.2 skrll */ 197 1.1.2.2 skrll TIMESPEC_TO_TIMEVAL(&tv, ts); 198 1.1.2.2 skrll return tvtohz(&tv); 199 1.1.2.2 skrll } 200 1.1.2.2 skrll 201 1.1.2.2 skrll /* 202 1.1.2.2 skrll * Check that a proposed value to load into the .it_value or 203 1.1.2.2 skrll * .it_interval part of an interval timer is acceptable, and 204 1.1.2.2 skrll * fix it to have at least minimal value (i.e. if it is less 205 1.1.2.2 skrll * than the resolution of the clock, round it up.) 206 1.1.2.2 skrll */ 207 1.1.2.2 skrll int 208 1.1.2.2 skrll itimerfix(struct timeval *tv) 209 1.1.2.2 skrll { 210 1.1.2.2 skrll 211 1.1.2.2 skrll if (tv->tv_sec < 0 || tv->tv_usec < 0 || tv->tv_usec >= 1000000) 212 1.1.2.2 skrll return (EINVAL); 213 1.1.2.2 skrll if (tv->tv_sec == 0 && tv->tv_usec != 0 && tv->tv_usec < tick) 214 1.1.2.2 skrll tv->tv_usec = tick; 215 1.1.2.2 skrll return (0); 216 1.1.2.2 skrll } 217 1.1.2.2 skrll 218 1.1.2.2 skrll int 219 1.1.2.2 skrll itimespecfix(struct timespec *ts) 220 1.1.2.2 skrll { 221 1.1.2.2 skrll 222 1.1.2.2 skrll if (ts->tv_sec < 0 || ts->tv_nsec < 0 || ts->tv_nsec >= 1000000000) 223 1.1.2.2 skrll return (EINVAL); 224 1.1.2.2 skrll if (ts->tv_sec == 0 && ts->tv_nsec != 0 && ts->tv_nsec < tick * 1000) 225 1.1.2.2 skrll ts->tv_nsec = tick * 1000; 226 1.1.2.2 skrll return (0); 227 1.1.2.2 skrll } 228
Indexes created Mon Sep 29 21:09:56 GMT 2025