1 | /*- |
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2 | * ---------------------------------------------------------------------------- |
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3 | * "THE BEER-WARE LICENSE" (Revision 42): |
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4 | * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you |
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5 | * can do whatever you want with this stuff. If we meet some day, and you think |
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6 | * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp |
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7 | * ---------------------------------------------------------------------------- |
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8 | * |
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9 | * Copyright (c) 2011, 2015, 2016 The FreeBSD Foundation |
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10 | * All rights reserved. |
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11 | * |
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12 | * Portions of this software were developed by Julien Ridoux at the University |
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13 | * of Melbourne under sponsorship from the FreeBSD Foundation. |
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14 | * |
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15 | * Portions of this software were developed by Konstantin Belousov |
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16 | * under sponsorship from the FreeBSD Foundation. |
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17 | */ |
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18 | |
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19 | #ifdef __rtems__ |
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20 | #include <sys/lock.h> |
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21 | #define _KERNEL |
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22 | #define binuptime(_bt) _Timecounter_Binuptime(_bt) |
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23 | #define nanouptime(_tsp) _Timecounter_Nanouptime(_tsp) |
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24 | #define microuptime(_tvp) _Timecounter_Microuptime(_tvp) |
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25 | #define bintime(_bt) _Timecounter_Bintime(_bt) |
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26 | #define nanotime(_tsp) _Timecounter_Nanotime(_tsp) |
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27 | #define microtime(_tvp) _Timecounter_Microtime(_tvp) |
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28 | #define getbinuptime(_bt) _Timecounter_Getbinuptime(_bt) |
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29 | #define getnanouptime(_tsp) _Timecounter_Getnanouptime(_tsp) |
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30 | #define getmicrouptime(_tvp) _Timecounter_Getmicrouptime(_tvp) |
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31 | #define getbintime(_bt) _Timecounter_Getbintime(_bt) |
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32 | #define getnanotime(_tsp) _Timecounter_Getnanotime(_tsp) |
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33 | #define getmicrotime(_tvp) _Timecounter_Getmicrotime(_tvp) |
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34 | #define getboottime(_tvp) _Timecounter_Getboottime(_tvp) |
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35 | #define getboottimebin(_bt) _Timecounter_Getboottimebin(_bt) |
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36 | #define tc_init _Timecounter_Install |
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37 | #define timecounter _Timecounter |
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38 | #define time_second _Timecounter_Time_second |
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39 | #define time_uptime _Timecounter_Time_uptime |
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40 | #include <rtems/score/timecounterimpl.h> |
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41 | #include <rtems/score/atomic.h> |
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42 | #include <rtems/score/smp.h> |
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43 | #include <rtems/score/todimpl.h> |
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44 | #include <rtems/score/watchdogimpl.h> |
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45 | #endif /* __rtems__ */ |
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46 | #include <sys/cdefs.h> |
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47 | __FBSDID("$FreeBSD: head/sys/kern/kern_tc.c 324528 2017-10-11 11:03:11Z kib $"); |
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48 | |
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49 | #include "opt_compat.h" |
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50 | #include "opt_ntp.h" |
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51 | #include "opt_ffclock.h" |
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52 | |
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53 | #include <sys/param.h> |
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54 | #ifndef __rtems__ |
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55 | #include <sys/kernel.h> |
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56 | #include <sys/limits.h> |
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57 | #include <sys/lock.h> |
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58 | #include <sys/mutex.h> |
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59 | #include <sys/proc.h> |
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60 | #include <sys/sbuf.h> |
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61 | #include <sys/sleepqueue.h> |
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62 | #include <sys/sysctl.h> |
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63 | #include <sys/syslog.h> |
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64 | #include <sys/systm.h> |
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65 | #endif /* __rtems__ */ |
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66 | #include <sys/timeffc.h> |
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67 | #include <sys/timepps.h> |
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68 | #include <sys/timetc.h> |
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69 | #include <sys/timex.h> |
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70 | #ifndef __rtems__ |
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71 | #include <sys/vdso.h> |
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72 | #endif /* __rtems__ */ |
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73 | #ifdef __rtems__ |
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74 | #include <limits.h> |
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75 | #include <string.h> |
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76 | #include <rtems.h> |
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77 | ISR_LOCK_DEFINE(, _Timecounter_Lock, "Timecounter") |
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78 | #define _Timecounter_Release(lock_context) \ |
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79 | _ISR_lock_Release_and_ISR_enable(&_Timecounter_Lock, lock_context) |
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80 | #define hz rtems_clock_get_ticks_per_second() |
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81 | #define printf(...) |
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82 | #define bcopy(x, y, z) memcpy(y, x, z); |
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83 | #define log(...) |
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84 | static inline int |
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85 | builtin_fls(int x) |
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86 | { |
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87 | return x ? sizeof(x) * 8 - __builtin_clz(x) : 0; |
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88 | } |
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89 | #define fls(x) builtin_fls(x) |
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90 | /* FIXME: https://devel.rtems.org/ticket/2348 */ |
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91 | #define ntp_update_second(a, b) do { (void) a; (void) b; } while (0) |
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92 | |
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93 | static inline void |
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94 | atomic_thread_fence_acq(void) |
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95 | { |
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96 | |
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97 | _Atomic_Fence(ATOMIC_ORDER_ACQUIRE); |
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98 | } |
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99 | |
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100 | static inline void |
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101 | atomic_thread_fence_rel(void) |
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102 | { |
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103 | |
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104 | _Atomic_Fence(ATOMIC_ORDER_RELEASE); |
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105 | } |
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106 | |
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107 | static inline u_int |
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108 | atomic_load_acq_int(Atomic_Uint *i) |
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109 | { |
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110 | |
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111 | return (_Atomic_Load_uint(i, ATOMIC_ORDER_ACQUIRE)); |
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112 | } |
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113 | |
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114 | static inline void |
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115 | atomic_store_rel_int(Atomic_Uint *i, u_int val) |
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116 | { |
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117 | |
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118 | _Atomic_Store_uint(i, val, ATOMIC_ORDER_RELEASE); |
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119 | } |
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120 | #endif /* __rtems__ */ |
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121 | |
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122 | /* |
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123 | * A large step happens on boot. This constant detects such steps. |
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124 | * It is relatively small so that ntp_update_second gets called enough |
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125 | * in the typical 'missed a couple of seconds' case, but doesn't loop |
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126 | * forever when the time step is large. |
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127 | */ |
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128 | #define LARGE_STEP 200 |
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129 | |
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130 | /* |
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131 | * Implement a dummy timecounter which we can use until we get a real one |
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132 | * in the air. This allows the console and other early stuff to use |
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133 | * time services. |
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134 | */ |
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135 | |
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136 | static uint32_t |
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137 | dummy_get_timecount(struct timecounter *tc) |
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138 | { |
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139 | #ifndef __rtems__ |
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140 | static uint32_t now; |
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141 | |
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142 | return (++now); |
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143 | #else /* __rtems__ */ |
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144 | return 0; |
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145 | #endif /* __rtems__ */ |
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146 | } |
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147 | |
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148 | static struct timecounter dummy_timecounter = { |
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149 | #ifndef __rtems__ |
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150 | dummy_get_timecount, 0, ~0u, 1000000, "dummy", -1000000 |
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151 | #else /* __rtems__ */ |
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152 | dummy_get_timecount, ~(uint32_t)0, 1000000, "dummy", -1000000 |
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153 | #endif /* __rtems__ */ |
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154 | }; |
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155 | |
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156 | struct timehands { |
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157 | /* These fields must be initialized by the driver. */ |
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158 | struct timecounter *th_counter; |
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159 | int64_t th_adjustment; |
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160 | uint64_t th_scale; |
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161 | uint32_t th_offset_count; |
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162 | struct bintime th_offset; |
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163 | struct bintime th_bintime; |
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164 | struct timeval th_microtime; |
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165 | struct timespec th_nanotime; |
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166 | struct bintime th_boottime; |
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167 | /* Fields not to be copied in tc_windup start with th_generation. */ |
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168 | #ifndef __rtems__ |
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169 | u_int th_generation; |
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170 | #else /* __rtems__ */ |
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171 | Atomic_Uint th_generation; |
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172 | #endif /* __rtems__ */ |
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173 | struct timehands *th_next; |
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174 | }; |
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175 | |
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176 | #if defined(RTEMS_SMP) |
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177 | static struct timehands th0; |
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178 | static struct timehands th1 = { |
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179 | .th_next = &th0 |
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180 | }; |
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181 | #endif |
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182 | static struct timehands th0 = { |
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183 | .th_counter = &dummy_timecounter, |
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184 | .th_scale = (uint64_t)-1 / 1000000, |
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185 | .th_offset = { .sec = 1 }, |
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186 | .th_generation = 1, |
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187 | #ifdef __rtems__ |
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188 | .th_bintime = { .sec = TOD_SECONDS_1970_THROUGH_1988 }, |
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189 | .th_microtime = { TOD_SECONDS_1970_THROUGH_1988, 0 }, |
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190 | .th_nanotime = { TOD_SECONDS_1970_THROUGH_1988, 0 }, |
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191 | .th_boottime = { .sec = TOD_SECONDS_1970_THROUGH_1988 - 1 }, |
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192 | #endif /* __rtems__ */ |
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193 | #if defined(RTEMS_SMP) |
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194 | .th_next = &th1 |
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195 | #else |
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196 | .th_next = &th0 |
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197 | #endif |
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198 | }; |
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199 | |
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200 | static struct timehands *volatile timehands = &th0; |
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201 | struct timecounter *timecounter = &dummy_timecounter; |
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202 | #ifndef __rtems__ |
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203 | static struct timecounter *timecounters = &dummy_timecounter; |
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204 | |
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205 | int tc_min_ticktock_freq = 1; |
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206 | #endif /* __rtems__ */ |
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207 | |
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208 | #ifndef __rtems__ |
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209 | volatile time_t time_second = 1; |
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210 | volatile time_t time_uptime = 1; |
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211 | #else /* __rtems__ */ |
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212 | volatile time_t time_second = TOD_SECONDS_1970_THROUGH_1988; |
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213 | volatile int32_t time_uptime = 1; |
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214 | #endif /* __rtems__ */ |
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215 | |
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216 | #ifndef __rtems__ |
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217 | static int sysctl_kern_boottime(SYSCTL_HANDLER_ARGS); |
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218 | SYSCTL_PROC(_kern, KERN_BOOTTIME, boottime, CTLTYPE_STRUCT|CTLFLAG_RD, |
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219 | NULL, 0, sysctl_kern_boottime, "S,timeval", "System boottime"); |
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220 | |
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221 | SYSCTL_NODE(_kern, OID_AUTO, timecounter, CTLFLAG_RW, 0, ""); |
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222 | static SYSCTL_NODE(_kern_timecounter, OID_AUTO, tc, CTLFLAG_RW, 0, ""); |
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223 | |
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224 | static int timestepwarnings; |
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225 | SYSCTL_INT(_kern_timecounter, OID_AUTO, stepwarnings, CTLFLAG_RW, |
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226 | ×tepwarnings, 0, "Log time steps"); |
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227 | |
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228 | struct bintime bt_timethreshold; |
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229 | struct bintime bt_tickthreshold; |
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230 | sbintime_t sbt_timethreshold; |
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231 | sbintime_t sbt_tickthreshold; |
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232 | struct bintime tc_tick_bt; |
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233 | sbintime_t tc_tick_sbt; |
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234 | int tc_precexp; |
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235 | int tc_timepercentage = TC_DEFAULTPERC; |
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236 | static int sysctl_kern_timecounter_adjprecision(SYSCTL_HANDLER_ARGS); |
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237 | SYSCTL_PROC(_kern_timecounter, OID_AUTO, alloweddeviation, |
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238 | CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_MPSAFE, 0, 0, |
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239 | sysctl_kern_timecounter_adjprecision, "I", |
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240 | "Allowed time interval deviation in percents"); |
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241 | |
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242 | volatile int rtc_generation = 1; |
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243 | |
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244 | static int tc_chosen; /* Non-zero if a specific tc was chosen via sysctl. */ |
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245 | #endif /* __rtems__ */ |
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246 | |
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247 | static void tc_windup(struct bintime *new_boottimebin); |
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248 | #ifndef __rtems__ |
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249 | static void cpu_tick_calibrate(int); |
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250 | #else /* __rtems__ */ |
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251 | static void _Timecounter_Windup(struct bintime *new_boottimebin, |
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252 | ISR_lock_Context *lock_context); |
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253 | #endif /* __rtems__ */ |
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254 | |
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255 | void dtrace_getnanotime(struct timespec *tsp); |
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256 | |
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257 | #ifndef __rtems__ |
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258 | static int |
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259 | sysctl_kern_boottime(SYSCTL_HANDLER_ARGS) |
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260 | { |
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261 | struct timeval boottime; |
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262 | |
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263 | getboottime(&boottime); |
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264 | |
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265 | #ifndef __mips__ |
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266 | #ifdef SCTL_MASK32 |
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267 | int tv[2]; |
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268 | |
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269 | if (req->flags & SCTL_MASK32) { |
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270 | tv[0] = boottime.tv_sec; |
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271 | tv[1] = boottime.tv_usec; |
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272 | return (SYSCTL_OUT(req, tv, sizeof(tv))); |
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273 | } |
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274 | #endif |
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275 | #endif |
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276 | return (SYSCTL_OUT(req, &boottime, sizeof(boottime))); |
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277 | } |
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278 | |
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279 | static int |
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280 | sysctl_kern_timecounter_get(SYSCTL_HANDLER_ARGS) |
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281 | { |
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282 | uint32_t ncount; |
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283 | struct timecounter *tc = arg1; |
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284 | |
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285 | ncount = tc->tc_get_timecount(tc); |
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286 | return (sysctl_handle_int(oidp, &ncount, 0, req)); |
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287 | } |
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288 | |
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289 | static int |
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290 | sysctl_kern_timecounter_freq(SYSCTL_HANDLER_ARGS) |
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291 | { |
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292 | uint64_t freq; |
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293 | struct timecounter *tc = arg1; |
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294 | |
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295 | freq = tc->tc_frequency; |
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296 | return (sysctl_handle_64(oidp, &freq, 0, req)); |
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297 | } |
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298 | #endif /* __rtems__ */ |
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299 | |
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300 | /* |
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301 | * Return the difference between the timehands' counter value now and what |
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302 | * was when we copied it to the timehands' offset_count. |
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303 | */ |
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304 | static __inline uint32_t |
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305 | tc_delta(struct timehands *th) |
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306 | { |
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307 | struct timecounter *tc; |
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308 | |
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309 | tc = th->th_counter; |
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310 | return ((tc->tc_get_timecount(tc) - th->th_offset_count) & |
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311 | tc->tc_counter_mask); |
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312 | } |
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313 | |
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314 | /* |
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315 | * Functions for reading the time. We have to loop until we are sure that |
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316 | * the timehands that we operated on was not updated under our feet. See |
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317 | * the comment in <sys/time.h> for a description of these 12 functions. |
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318 | */ |
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319 | |
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320 | #ifdef FFCLOCK |
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321 | void |
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322 | fbclock_binuptime(struct bintime *bt) |
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323 | { |
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324 | struct timehands *th; |
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325 | unsigned int gen; |
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326 | |
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327 | do { |
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328 | th = timehands; |
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329 | gen = atomic_load_acq_int(&th->th_generation); |
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330 | *bt = th->th_offset; |
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331 | bintime_addx(bt, th->th_scale * tc_delta(th)); |
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332 | atomic_thread_fence_acq(); |
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333 | } while (gen == 0 || gen != th->th_generation); |
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334 | } |
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335 | |
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336 | void |
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337 | fbclock_nanouptime(struct timespec *tsp) |
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338 | { |
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339 | struct bintime bt; |
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340 | |
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341 | fbclock_binuptime(&bt); |
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342 | bintime2timespec(&bt, tsp); |
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343 | } |
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344 | |
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345 | void |
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346 | fbclock_microuptime(struct timeval *tvp) |
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347 | { |
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348 | struct bintime bt; |
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349 | |
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350 | fbclock_binuptime(&bt); |
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351 | bintime2timeval(&bt, tvp); |
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352 | } |
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353 | |
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354 | void |
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355 | fbclock_bintime(struct bintime *bt) |
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356 | { |
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357 | struct timehands *th; |
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358 | unsigned int gen; |
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359 | |
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360 | do { |
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361 | th = timehands; |
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362 | gen = atomic_load_acq_int(&th->th_generation); |
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363 | *bt = th->th_bintime; |
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364 | bintime_addx(bt, th->th_scale * tc_delta(th)); |
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365 | atomic_thread_fence_acq(); |
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366 | } while (gen == 0 || gen != th->th_generation); |
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367 | } |
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368 | |
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369 | void |
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370 | fbclock_nanotime(struct timespec *tsp) |
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371 | { |
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372 | struct bintime bt; |
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373 | |
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374 | fbclock_bintime(&bt); |
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375 | bintime2timespec(&bt, tsp); |
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376 | } |
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377 | |
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378 | void |
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379 | fbclock_microtime(struct timeval *tvp) |
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380 | { |
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381 | struct bintime bt; |
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382 | |
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383 | fbclock_bintime(&bt); |
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384 | bintime2timeval(&bt, tvp); |
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385 | } |
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386 | |
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387 | void |
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388 | fbclock_getbinuptime(struct bintime *bt) |
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389 | { |
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390 | struct timehands *th; |
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391 | unsigned int gen; |
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392 | |
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393 | do { |
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394 | th = timehands; |
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395 | gen = atomic_load_acq_int(&th->th_generation); |
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396 | *bt = th->th_offset; |
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397 | atomic_thread_fence_acq(); |
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398 | } while (gen == 0 || gen != th->th_generation); |
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399 | } |
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400 | |
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401 | void |
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402 | fbclock_getnanouptime(struct timespec *tsp) |
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403 | { |
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404 | struct timehands *th; |
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405 | unsigned int gen; |
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406 | |
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407 | do { |
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408 | th = timehands; |
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409 | gen = atomic_load_acq_int(&th->th_generation); |
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410 | bintime2timespec(&th->th_offset, tsp); |
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411 | atomic_thread_fence_acq(); |
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412 | } while (gen == 0 || gen != th->th_generation); |
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413 | } |
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414 | |
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415 | void |
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416 | fbclock_getmicrouptime(struct timeval *tvp) |
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417 | { |
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418 | struct timehands *th; |
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419 | unsigned int gen; |
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420 | |
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421 | do { |
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422 | th = timehands; |
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423 | gen = atomic_load_acq_int(&th->th_generation); |
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424 | bintime2timeval(&th->th_offset, tvp); |
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425 | atomic_thread_fence_acq(); |
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426 | } while (gen == 0 || gen != th->th_generation); |
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427 | } |
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428 | |
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429 | void |
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430 | fbclock_getbintime(struct bintime *bt) |
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431 | { |
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432 | struct timehands *th; |
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433 | unsigned int gen; |
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434 | |
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435 | do { |
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436 | th = timehands; |
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437 | gen = atomic_load_acq_int(&th->th_generation); |
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438 | *bt = th->th_bintime; |
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439 | atomic_thread_fence_acq(); |
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440 | } while (gen == 0 || gen != th->th_generation); |
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441 | } |
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442 | |
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443 | void |
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444 | fbclock_getnanotime(struct timespec *tsp) |
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445 | { |
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446 | struct timehands *th; |
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447 | unsigned int gen; |
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448 | |
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449 | do { |
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450 | th = timehands; |
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451 | gen = atomic_load_acq_int(&th->th_generation); |
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452 | *tsp = th->th_nanotime; |
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453 | atomic_thread_fence_acq(); |
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454 | } while (gen == 0 || gen != th->th_generation); |
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455 | } |
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456 | |
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457 | void |
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458 | fbclock_getmicrotime(struct timeval *tvp) |
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459 | { |
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460 | struct timehands *th; |
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461 | unsigned int gen; |
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462 | |
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463 | do { |
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464 | th = timehands; |
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465 | gen = atomic_load_acq_int(&th->th_generation); |
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466 | *tvp = th->th_microtime; |
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467 | atomic_thread_fence_acq(); |
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468 | } while (gen == 0 || gen != th->th_generation); |
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469 | } |
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470 | #else /* !FFCLOCK */ |
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471 | void |
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472 | binuptime(struct bintime *bt) |
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473 | { |
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474 | struct timehands *th; |
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475 | uint32_t gen; |
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476 | |
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477 | do { |
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478 | th = timehands; |
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479 | gen = atomic_load_acq_int(&th->th_generation); |
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480 | *bt = th->th_offset; |
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481 | bintime_addx(bt, th->th_scale * tc_delta(th)); |
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482 | atomic_thread_fence_acq(); |
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483 | } while (gen == 0 || gen != th->th_generation); |
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484 | } |
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485 | #ifdef __rtems__ |
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486 | sbintime_t |
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487 | _Timecounter_Sbinuptime(void) |
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488 | { |
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489 | struct timehands *th; |
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490 | uint32_t gen; |
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491 | sbintime_t sbt; |
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492 | |
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493 | do { |
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494 | th = timehands; |
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495 | gen = atomic_load_acq_int(&th->th_generation); |
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496 | sbt = bttosbt(th->th_offset); |
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497 | sbt += (th->th_scale * tc_delta(th)) >> 32; |
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498 | atomic_thread_fence_acq(); |
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499 | } while (gen == 0 || gen != th->th_generation); |
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500 | |
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501 | return (sbt); |
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502 | } |
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503 | #endif /* __rtems__ */ |
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504 | |
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505 | void |
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506 | nanouptime(struct timespec *tsp) |
---|
507 | { |
---|
508 | struct bintime bt; |
---|
509 | |
---|
510 | binuptime(&bt); |
---|
511 | bintime2timespec(&bt, tsp); |
---|
512 | } |
---|
513 | |
---|
514 | void |
---|
515 | microuptime(struct timeval *tvp) |
---|
516 | { |
---|
517 | struct bintime bt; |
---|
518 | |
---|
519 | binuptime(&bt); |
---|
520 | bintime2timeval(&bt, tvp); |
---|
521 | } |
---|
522 | |
---|
523 | void |
---|
524 | bintime(struct bintime *bt) |
---|
525 | { |
---|
526 | struct timehands *th; |
---|
527 | u_int gen; |
---|
528 | |
---|
529 | do { |
---|
530 | th = timehands; |
---|
531 | gen = atomic_load_acq_int(&th->th_generation); |
---|
532 | *bt = th->th_bintime; |
---|
533 | bintime_addx(bt, th->th_scale * tc_delta(th)); |
---|
534 | atomic_thread_fence_acq(); |
---|
535 | } while (gen == 0 || gen != th->th_generation); |
---|
536 | } |
---|
537 | |
---|
538 | void |
---|
539 | nanotime(struct timespec *tsp) |
---|
540 | { |
---|
541 | struct bintime bt; |
---|
542 | |
---|
543 | bintime(&bt); |
---|
544 | bintime2timespec(&bt, tsp); |
---|
545 | } |
---|
546 | |
---|
547 | void |
---|
548 | microtime(struct timeval *tvp) |
---|
549 | { |
---|
550 | struct bintime bt; |
---|
551 | |
---|
552 | bintime(&bt); |
---|
553 | bintime2timeval(&bt, tvp); |
---|
554 | } |
---|
555 | |
---|
556 | void |
---|
557 | getbinuptime(struct bintime *bt) |
---|
558 | { |
---|
559 | struct timehands *th; |
---|
560 | uint32_t gen; |
---|
561 | |
---|
562 | do { |
---|
563 | th = timehands; |
---|
564 | gen = atomic_load_acq_int(&th->th_generation); |
---|
565 | *bt = th->th_offset; |
---|
566 | atomic_thread_fence_acq(); |
---|
567 | } while (gen == 0 || gen != th->th_generation); |
---|
568 | } |
---|
569 | |
---|
570 | void |
---|
571 | getnanouptime(struct timespec *tsp) |
---|
572 | { |
---|
573 | struct timehands *th; |
---|
574 | uint32_t gen; |
---|
575 | |
---|
576 | do { |
---|
577 | th = timehands; |
---|
578 | gen = atomic_load_acq_int(&th->th_generation); |
---|
579 | bintime2timespec(&th->th_offset, tsp); |
---|
580 | atomic_thread_fence_acq(); |
---|
581 | } while (gen == 0 || gen != th->th_generation); |
---|
582 | } |
---|
583 | |
---|
584 | void |
---|
585 | getmicrouptime(struct timeval *tvp) |
---|
586 | { |
---|
587 | struct timehands *th; |
---|
588 | uint32_t gen; |
---|
589 | |
---|
590 | do { |
---|
591 | th = timehands; |
---|
592 | gen = atomic_load_acq_int(&th->th_generation); |
---|
593 | bintime2timeval(&th->th_offset, tvp); |
---|
594 | atomic_thread_fence_acq(); |
---|
595 | } while (gen == 0 || gen != th->th_generation); |
---|
596 | } |
---|
597 | |
---|
598 | void |
---|
599 | getbintime(struct bintime *bt) |
---|
600 | { |
---|
601 | struct timehands *th; |
---|
602 | uint32_t gen; |
---|
603 | |
---|
604 | do { |
---|
605 | th = timehands; |
---|
606 | gen = atomic_load_acq_int(&th->th_generation); |
---|
607 | *bt = th->th_bintime; |
---|
608 | atomic_thread_fence_acq(); |
---|
609 | } while (gen == 0 || gen != th->th_generation); |
---|
610 | } |
---|
611 | |
---|
612 | void |
---|
613 | getnanotime(struct timespec *tsp) |
---|
614 | { |
---|
615 | struct timehands *th; |
---|
616 | uint32_t gen; |
---|
617 | |
---|
618 | do { |
---|
619 | th = timehands; |
---|
620 | gen = atomic_load_acq_int(&th->th_generation); |
---|
621 | *tsp = th->th_nanotime; |
---|
622 | atomic_thread_fence_acq(); |
---|
623 | } while (gen == 0 || gen != th->th_generation); |
---|
624 | } |
---|
625 | |
---|
626 | void |
---|
627 | getmicrotime(struct timeval *tvp) |
---|
628 | { |
---|
629 | struct timehands *th; |
---|
630 | uint32_t gen; |
---|
631 | |
---|
632 | do { |
---|
633 | th = timehands; |
---|
634 | gen = atomic_load_acq_int(&th->th_generation); |
---|
635 | *tvp = th->th_microtime; |
---|
636 | atomic_thread_fence_acq(); |
---|
637 | } while (gen == 0 || gen != th->th_generation); |
---|
638 | } |
---|
639 | #endif /* FFCLOCK */ |
---|
640 | |
---|
641 | void |
---|
642 | getboottime(struct timeval *boottime) |
---|
643 | { |
---|
644 | struct bintime boottimebin; |
---|
645 | |
---|
646 | getboottimebin(&boottimebin); |
---|
647 | bintime2timeval(&boottimebin, boottime); |
---|
648 | } |
---|
649 | |
---|
650 | void |
---|
651 | getboottimebin(struct bintime *boottimebin) |
---|
652 | { |
---|
653 | struct timehands *th; |
---|
654 | u_int gen; |
---|
655 | |
---|
656 | do { |
---|
657 | th = timehands; |
---|
658 | gen = atomic_load_acq_int(&th->th_generation); |
---|
659 | *boottimebin = th->th_boottime; |
---|
660 | atomic_thread_fence_acq(); |
---|
661 | } while (gen == 0 || gen != th->th_generation); |
---|
662 | } |
---|
663 | |
---|
664 | #ifdef FFCLOCK |
---|
665 | /* |
---|
666 | * Support for feed-forward synchronization algorithms. This is heavily inspired |
---|
667 | * by the timehands mechanism but kept independent from it. *_windup() functions |
---|
668 | * have some connection to avoid accessing the timecounter hardware more than |
---|
669 | * necessary. |
---|
670 | */ |
---|
671 | |
---|
672 | /* Feed-forward clock estimates kept updated by the synchronization daemon. */ |
---|
673 | struct ffclock_estimate ffclock_estimate; |
---|
674 | struct bintime ffclock_boottime; /* Feed-forward boot time estimate. */ |
---|
675 | uint32_t ffclock_status; /* Feed-forward clock status. */ |
---|
676 | int8_t ffclock_updated; /* New estimates are available. */ |
---|
677 | struct mtx ffclock_mtx; /* Mutex on ffclock_estimate. */ |
---|
678 | |
---|
679 | struct fftimehands { |
---|
680 | struct ffclock_estimate cest; |
---|
681 | struct bintime tick_time; |
---|
682 | struct bintime tick_time_lerp; |
---|
683 | ffcounter tick_ffcount; |
---|
684 | uint64_t period_lerp; |
---|
685 | volatile uint8_t gen; |
---|
686 | struct fftimehands *next; |
---|
687 | }; |
---|
688 | |
---|
689 | #define NUM_ELEMENTS(x) (sizeof(x) / sizeof(*x)) |
---|
690 | |
---|
691 | static struct fftimehands ffth[10]; |
---|
692 | static struct fftimehands *volatile fftimehands = ffth; |
---|
693 | |
---|
694 | static void |
---|
695 | ffclock_init(void) |
---|
696 | { |
---|
697 | struct fftimehands *cur; |
---|
698 | struct fftimehands *last; |
---|
699 | |
---|
700 | memset(ffth, 0, sizeof(ffth)); |
---|
701 | |
---|
702 | last = ffth + NUM_ELEMENTS(ffth) - 1; |
---|
703 | for (cur = ffth; cur < last; cur++) |
---|
704 | cur->next = cur + 1; |
---|
705 | last->next = ffth; |
---|
706 | |
---|
707 | ffclock_updated = 0; |
---|
708 | ffclock_status = FFCLOCK_STA_UNSYNC; |
---|
709 | mtx_init(&ffclock_mtx, "ffclock lock", NULL, MTX_DEF); |
---|
710 | } |
---|
711 | |
---|
712 | /* |
---|
713 | * Reset the feed-forward clock estimates. Called from inittodr() to get things |
---|
714 | * kick started and uses the timecounter nominal frequency as a first period |
---|
715 | * estimate. Note: this function may be called several time just after boot. |
---|
716 | * Note: this is the only function that sets the value of boot time for the |
---|
717 | * monotonic (i.e. uptime) version of the feed-forward clock. |
---|
718 | */ |
---|
719 | void |
---|
720 | ffclock_reset_clock(struct timespec *ts) |
---|
721 | { |
---|
722 | struct timecounter *tc; |
---|
723 | struct ffclock_estimate cest; |
---|
724 | |
---|
725 | tc = timehands->th_counter; |
---|
726 | memset(&cest, 0, sizeof(struct ffclock_estimate)); |
---|
727 | |
---|
728 | timespec2bintime(ts, &ffclock_boottime); |
---|
729 | timespec2bintime(ts, &(cest.update_time)); |
---|
730 | ffclock_read_counter(&cest.update_ffcount); |
---|
731 | cest.leapsec_next = 0; |
---|
732 | cest.period = ((1ULL << 63) / tc->tc_frequency) << 1; |
---|
733 | cest.errb_abs = 0; |
---|
734 | cest.errb_rate = 0; |
---|
735 | cest.status = FFCLOCK_STA_UNSYNC; |
---|
736 | cest.leapsec_total = 0; |
---|
737 | cest.leapsec = 0; |
---|
738 | |
---|
739 | mtx_lock(&ffclock_mtx); |
---|
740 | bcopy(&cest, &ffclock_estimate, sizeof(struct ffclock_estimate)); |
---|
741 | ffclock_updated = INT8_MAX; |
---|
742 | mtx_unlock(&ffclock_mtx); |
---|
743 | |
---|
744 | printf("ffclock reset: %s (%llu Hz), time = %ld.%09lu\n", tc->tc_name, |
---|
745 | (unsigned long long)tc->tc_frequency, (long)ts->tv_sec, |
---|
746 | (unsigned long)ts->tv_nsec); |
---|
747 | } |
---|
748 | |
---|
749 | /* |
---|
750 | * Sub-routine to convert a time interval measured in RAW counter units to time |
---|
751 | * in seconds stored in bintime format. |
---|
752 | * NOTE: bintime_mul requires u_int, but the value of the ffcounter may be |
---|
753 | * larger than the max value of u_int (on 32 bit architecture). Loop to consume |
---|
754 | * extra cycles. |
---|
755 | */ |
---|
756 | static void |
---|
757 | ffclock_convert_delta(ffcounter ffdelta, uint64_t period, struct bintime *bt) |
---|
758 | { |
---|
759 | struct bintime bt2; |
---|
760 | ffcounter delta, delta_max; |
---|
761 | |
---|
762 | delta_max = (1ULL << (8 * sizeof(unsigned int))) - 1; |
---|
763 | bintime_clear(bt); |
---|
764 | do { |
---|
765 | if (ffdelta > delta_max) |
---|
766 | delta = delta_max; |
---|
767 | else |
---|
768 | delta = ffdelta; |
---|
769 | bt2.sec = 0; |
---|
770 | bt2.frac = period; |
---|
771 | bintime_mul(&bt2, (unsigned int)delta); |
---|
772 | bintime_add(bt, &bt2); |
---|
773 | ffdelta -= delta; |
---|
774 | } while (ffdelta > 0); |
---|
775 | } |
---|
776 | |
---|
777 | /* |
---|
778 | * Update the fftimehands. |
---|
779 | * Push the tick ffcount and time(s) forward based on current clock estimate. |
---|
780 | * The conversion from ffcounter to bintime relies on the difference clock |
---|
781 | * principle, whose accuracy relies on computing small time intervals. If a new |
---|
782 | * clock estimate has been passed by the synchronisation daemon, make it |
---|
783 | * current, and compute the linear interpolation for monotonic time if needed. |
---|
784 | */ |
---|
785 | static void |
---|
786 | ffclock_windup(unsigned int delta) |
---|
787 | { |
---|
788 | struct ffclock_estimate *cest; |
---|
789 | struct fftimehands *ffth; |
---|
790 | struct bintime bt, gap_lerp; |
---|
791 | ffcounter ffdelta; |
---|
792 | uint64_t frac; |
---|
793 | unsigned int polling; |
---|
794 | uint8_t forward_jump, ogen; |
---|
795 | |
---|
796 | /* |
---|
797 | * Pick the next timehand, copy current ffclock estimates and move tick |
---|
798 | * times and counter forward. |
---|
799 | */ |
---|
800 | forward_jump = 0; |
---|
801 | ffth = fftimehands->next; |
---|
802 | ogen = ffth->gen; |
---|
803 | ffth->gen = 0; |
---|
804 | cest = &ffth->cest; |
---|
805 | bcopy(&fftimehands->cest, cest, sizeof(struct ffclock_estimate)); |
---|
806 | ffdelta = (ffcounter)delta; |
---|
807 | ffth->period_lerp = fftimehands->period_lerp; |
---|
808 | |
---|
809 | ffth->tick_time = fftimehands->tick_time; |
---|
810 | ffclock_convert_delta(ffdelta, cest->period, &bt); |
---|
811 | bintime_add(&ffth->tick_time, &bt); |
---|
812 | |
---|
813 | ffth->tick_time_lerp = fftimehands->tick_time_lerp; |
---|
814 | ffclock_convert_delta(ffdelta, ffth->period_lerp, &bt); |
---|
815 | bintime_add(&ffth->tick_time_lerp, &bt); |
---|
816 | |
---|
817 | ffth->tick_ffcount = fftimehands->tick_ffcount + ffdelta; |
---|
818 | |
---|
819 | /* |
---|
820 | * Assess the status of the clock, if the last update is too old, it is |
---|
821 | * likely the synchronisation daemon is dead and the clock is free |
---|
822 | * running. |
---|
823 | */ |
---|
824 | if (ffclock_updated == 0) { |
---|
825 | ffdelta = ffth->tick_ffcount - cest->update_ffcount; |
---|
826 | ffclock_convert_delta(ffdelta, cest->period, &bt); |
---|
827 | if (bt.sec > 2 * FFCLOCK_SKM_SCALE) |
---|
828 | ffclock_status |= FFCLOCK_STA_UNSYNC; |
---|
829 | } |
---|
830 | |
---|
831 | /* |
---|
832 | * If available, grab updated clock estimates and make them current. |
---|
833 | * Recompute time at this tick using the updated estimates. The clock |
---|
834 | * estimates passed the feed-forward synchronisation daemon may result |
---|
835 | * in time conversion that is not monotonically increasing (just after |
---|
836 | * the update). time_lerp is a particular linear interpolation over the |
---|
837 | * synchronisation algo polling period that ensures monotonicity for the |
---|
838 | * clock ids requesting it. |
---|
839 | */ |
---|
840 | if (ffclock_updated > 0) { |
---|
841 | bcopy(&ffclock_estimate, cest, sizeof(struct ffclock_estimate)); |
---|
842 | ffdelta = ffth->tick_ffcount - cest->update_ffcount; |
---|
843 | ffth->tick_time = cest->update_time; |
---|
844 | ffclock_convert_delta(ffdelta, cest->period, &bt); |
---|
845 | bintime_add(&ffth->tick_time, &bt); |
---|
846 | |
---|
847 | /* ffclock_reset sets ffclock_updated to INT8_MAX */ |
---|
848 | if (ffclock_updated == INT8_MAX) |
---|
849 | ffth->tick_time_lerp = ffth->tick_time; |
---|
850 | |
---|
851 | if (bintime_cmp(&ffth->tick_time, &ffth->tick_time_lerp, >)) |
---|
852 | forward_jump = 1; |
---|
853 | else |
---|
854 | forward_jump = 0; |
---|
855 | |
---|
856 | bintime_clear(&gap_lerp); |
---|
857 | if (forward_jump) { |
---|
858 | gap_lerp = ffth->tick_time; |
---|
859 | bintime_sub(&gap_lerp, &ffth->tick_time_lerp); |
---|
860 | } else { |
---|
861 | gap_lerp = ffth->tick_time_lerp; |
---|
862 | bintime_sub(&gap_lerp, &ffth->tick_time); |
---|
863 | } |
---|
864 | |
---|
865 | /* |
---|
866 | * The reset from the RTC clock may be far from accurate, and |
---|
867 | * reducing the gap between real time and interpolated time |
---|
868 | * could take a very long time if the interpolated clock insists |
---|
869 | * on strict monotonicity. The clock is reset under very strict |
---|
870 | * conditions (kernel time is known to be wrong and |
---|
871 | * synchronization daemon has been restarted recently. |
---|
872 | * ffclock_boottime absorbs the jump to ensure boot time is |
---|
873 | * correct and uptime functions stay consistent. |
---|
874 | */ |
---|
875 | if (((ffclock_status & FFCLOCK_STA_UNSYNC) == FFCLOCK_STA_UNSYNC) && |
---|
876 | ((cest->status & FFCLOCK_STA_UNSYNC) == 0) && |
---|
877 | ((cest->status & FFCLOCK_STA_WARMUP) == FFCLOCK_STA_WARMUP)) { |
---|
878 | if (forward_jump) |
---|
879 | bintime_add(&ffclock_boottime, &gap_lerp); |
---|
880 | else |
---|
881 | bintime_sub(&ffclock_boottime, &gap_lerp); |
---|
882 | ffth->tick_time_lerp = ffth->tick_time; |
---|
883 | bintime_clear(&gap_lerp); |
---|
884 | } |
---|
885 | |
---|
886 | ffclock_status = cest->status; |
---|
887 | ffth->period_lerp = cest->period; |
---|
888 | |
---|
889 | /* |
---|
890 | * Compute corrected period used for the linear interpolation of |
---|
891 | * time. The rate of linear interpolation is capped to 5000PPM |
---|
892 | * (5ms/s). |
---|
893 | */ |
---|
894 | if (bintime_isset(&gap_lerp)) { |
---|
895 | ffdelta = cest->update_ffcount; |
---|
896 | ffdelta -= fftimehands->cest.update_ffcount; |
---|
897 | ffclock_convert_delta(ffdelta, cest->period, &bt); |
---|
898 | polling = bt.sec; |
---|
899 | bt.sec = 0; |
---|
900 | bt.frac = 5000000 * (uint64_t)18446744073LL; |
---|
901 | bintime_mul(&bt, polling); |
---|
902 | if (bintime_cmp(&gap_lerp, &bt, >)) |
---|
903 | gap_lerp = bt; |
---|
904 | |
---|
905 | /* Approximate 1 sec by 1-(1/2^64) to ease arithmetic */ |
---|
906 | frac = 0; |
---|
907 | if (gap_lerp.sec > 0) { |
---|
908 | frac -= 1; |
---|
909 | frac /= ffdelta / gap_lerp.sec; |
---|
910 | } |
---|
911 | frac += gap_lerp.frac / ffdelta; |
---|
912 | |
---|
913 | if (forward_jump) |
---|
914 | ffth->period_lerp += frac; |
---|
915 | else |
---|
916 | ffth->period_lerp -= frac; |
---|
917 | } |
---|
918 | |
---|
919 | ffclock_updated = 0; |
---|
920 | } |
---|
921 | if (++ogen == 0) |
---|
922 | ogen = 1; |
---|
923 | ffth->gen = ogen; |
---|
924 | fftimehands = ffth; |
---|
925 | } |
---|
926 | |
---|
927 | /* |
---|
928 | * Adjust the fftimehands when the timecounter is changed. Stating the obvious, |
---|
929 | * the old and new hardware counter cannot be read simultaneously. tc_windup() |
---|
930 | * does read the two counters 'back to back', but a few cycles are effectively |
---|
931 | * lost, and not accumulated in tick_ffcount. This is a fairly radical |
---|
932 | * operation for a feed-forward synchronization daemon, and it is its job to not |
---|
933 | * pushing irrelevant data to the kernel. Because there is no locking here, |
---|
934 | * simply force to ignore pending or next update to give daemon a chance to |
---|
935 | * realize the counter has changed. |
---|
936 | */ |
---|
937 | static void |
---|
938 | ffclock_change_tc(struct timehands *th) |
---|
939 | { |
---|
940 | struct fftimehands *ffth; |
---|
941 | struct ffclock_estimate *cest; |
---|
942 | struct timecounter *tc; |
---|
943 | uint8_t ogen; |
---|
944 | |
---|
945 | tc = th->th_counter; |
---|
946 | ffth = fftimehands->next; |
---|
947 | ogen = ffth->gen; |
---|
948 | ffth->gen = 0; |
---|
949 | |
---|
950 | cest = &ffth->cest; |
---|
951 | bcopy(&(fftimehands->cest), cest, sizeof(struct ffclock_estimate)); |
---|
952 | cest->period = ((1ULL << 63) / tc->tc_frequency ) << 1; |
---|
953 | cest->errb_abs = 0; |
---|
954 | cest->errb_rate = 0; |
---|
955 | cest->status |= FFCLOCK_STA_UNSYNC; |
---|
956 | |
---|
957 | ffth->tick_ffcount = fftimehands->tick_ffcount; |
---|
958 | ffth->tick_time_lerp = fftimehands->tick_time_lerp; |
---|
959 | ffth->tick_time = fftimehands->tick_time; |
---|
960 | ffth->period_lerp = cest->period; |
---|
961 | |
---|
962 | /* Do not lock but ignore next update from synchronization daemon. */ |
---|
963 | ffclock_updated--; |
---|
964 | |
---|
965 | if (++ogen == 0) |
---|
966 | ogen = 1; |
---|
967 | ffth->gen = ogen; |
---|
968 | fftimehands = ffth; |
---|
969 | } |
---|
970 | |
---|
971 | /* |
---|
972 | * Retrieve feed-forward counter and time of last kernel tick. |
---|
973 | */ |
---|
974 | void |
---|
975 | ffclock_last_tick(ffcounter *ffcount, struct bintime *bt, uint32_t flags) |
---|
976 | { |
---|
977 | struct fftimehands *ffth; |
---|
978 | uint8_t gen; |
---|
979 | |
---|
980 | /* |
---|
981 | * No locking but check generation has not changed. Also need to make |
---|
982 | * sure ffdelta is positive, i.e. ffcount > tick_ffcount. |
---|
983 | */ |
---|
984 | do { |
---|
985 | ffth = fftimehands; |
---|
986 | gen = ffth->gen; |
---|
987 | if ((flags & FFCLOCK_LERP) == FFCLOCK_LERP) |
---|
988 | *bt = ffth->tick_time_lerp; |
---|
989 | else |
---|
990 | *bt = ffth->tick_time; |
---|
991 | *ffcount = ffth->tick_ffcount; |
---|
992 | } while (gen == 0 || gen != ffth->gen); |
---|
993 | } |
---|
994 | |
---|
995 | /* |
---|
996 | * Absolute clock conversion. Low level function to convert ffcounter to |
---|
997 | * bintime. The ffcounter is converted using the current ffclock period estimate |
---|
998 | * or the "interpolated period" to ensure monotonicity. |
---|
999 | * NOTE: this conversion may have been deferred, and the clock updated since the |
---|
1000 | * hardware counter has been read. |
---|
1001 | */ |
---|
1002 | void |
---|
1003 | ffclock_convert_abs(ffcounter ffcount, struct bintime *bt, uint32_t flags) |
---|
1004 | { |
---|
1005 | struct fftimehands *ffth; |
---|
1006 | struct bintime bt2; |
---|
1007 | ffcounter ffdelta; |
---|
1008 | uint8_t gen; |
---|
1009 | |
---|
1010 | /* |
---|
1011 | * No locking but check generation has not changed. Also need to make |
---|
1012 | * sure ffdelta is positive, i.e. ffcount > tick_ffcount. |
---|
1013 | */ |
---|
1014 | do { |
---|
1015 | ffth = fftimehands; |
---|
1016 | gen = ffth->gen; |
---|
1017 | if (ffcount > ffth->tick_ffcount) |
---|
1018 | ffdelta = ffcount - ffth->tick_ffcount; |
---|
1019 | else |
---|
1020 | ffdelta = ffth->tick_ffcount - ffcount; |
---|
1021 | |
---|
1022 | if ((flags & FFCLOCK_LERP) == FFCLOCK_LERP) { |
---|
1023 | *bt = ffth->tick_time_lerp; |
---|
1024 | ffclock_convert_delta(ffdelta, ffth->period_lerp, &bt2); |
---|
1025 | } else { |
---|
1026 | *bt = ffth->tick_time; |
---|
1027 | ffclock_convert_delta(ffdelta, ffth->cest.period, &bt2); |
---|
1028 | } |
---|
1029 | |
---|
1030 | if (ffcount > ffth->tick_ffcount) |
---|
1031 | bintime_add(bt, &bt2); |
---|
1032 | else |
---|
1033 | bintime_sub(bt, &bt2); |
---|
1034 | } while (gen == 0 || gen != ffth->gen); |
---|
1035 | } |
---|
1036 | |
---|
1037 | /* |
---|
1038 | * Difference clock conversion. |
---|
1039 | * Low level function to Convert a time interval measured in RAW counter units |
---|
1040 | * into bintime. The difference clock allows measuring small intervals much more |
---|
1041 | * reliably than the absolute clock. |
---|
1042 | */ |
---|
1043 | void |
---|
1044 | ffclock_convert_diff(ffcounter ffdelta, struct bintime *bt) |
---|
1045 | { |
---|
1046 | struct fftimehands *ffth; |
---|
1047 | uint8_t gen; |
---|
1048 | |
---|
1049 | /* No locking but check generation has not changed. */ |
---|
1050 | do { |
---|
1051 | ffth = fftimehands; |
---|
1052 | gen = ffth->gen; |
---|
1053 | ffclock_convert_delta(ffdelta, ffth->cest.period, bt); |
---|
1054 | } while (gen == 0 || gen != ffth->gen); |
---|
1055 | } |
---|
1056 | |
---|
1057 | /* |
---|
1058 | * Access to current ffcounter value. |
---|
1059 | */ |
---|
1060 | void |
---|
1061 | ffclock_read_counter(ffcounter *ffcount) |
---|
1062 | { |
---|
1063 | struct timehands *th; |
---|
1064 | struct fftimehands *ffth; |
---|
1065 | unsigned int gen, delta; |
---|
1066 | |
---|
1067 | /* |
---|
1068 | * ffclock_windup() called from tc_windup(), safe to rely on |
---|
1069 | * th->th_generation only, for correct delta and ffcounter. |
---|
1070 | */ |
---|
1071 | do { |
---|
1072 | th = timehands; |
---|
1073 | gen = atomic_load_acq_int(&th->th_generation); |
---|
1074 | ffth = fftimehands; |
---|
1075 | delta = tc_delta(th); |
---|
1076 | *ffcount = ffth->tick_ffcount; |
---|
1077 | atomic_thread_fence_acq(); |
---|
1078 | } while (gen == 0 || gen != th->th_generation); |
---|
1079 | |
---|
1080 | *ffcount += delta; |
---|
1081 | } |
---|
1082 | |
---|
1083 | void |
---|
1084 | binuptime(struct bintime *bt) |
---|
1085 | { |
---|
1086 | |
---|
1087 | binuptime_fromclock(bt, sysclock_active); |
---|
1088 | } |
---|
1089 | |
---|
1090 | void |
---|
1091 | nanouptime(struct timespec *tsp) |
---|
1092 | { |
---|
1093 | |
---|
1094 | nanouptime_fromclock(tsp, sysclock_active); |
---|
1095 | } |
---|
1096 | |
---|
1097 | void |
---|
1098 | microuptime(struct timeval *tvp) |
---|
1099 | { |
---|
1100 | |
---|
1101 | microuptime_fromclock(tvp, sysclock_active); |
---|
1102 | } |
---|
1103 | |
---|
1104 | void |
---|
1105 | bintime(struct bintime *bt) |
---|
1106 | { |
---|
1107 | |
---|
1108 | bintime_fromclock(bt, sysclock_active); |
---|
1109 | } |
---|
1110 | |
---|
1111 | void |
---|
1112 | nanotime(struct timespec *tsp) |
---|
1113 | { |
---|
1114 | |
---|
1115 | nanotime_fromclock(tsp, sysclock_active); |
---|
1116 | } |
---|
1117 | |
---|
1118 | void |
---|
1119 | microtime(struct timeval *tvp) |
---|
1120 | { |
---|
1121 | |
---|
1122 | microtime_fromclock(tvp, sysclock_active); |
---|
1123 | } |
---|
1124 | |
---|
1125 | void |
---|
1126 | getbinuptime(struct bintime *bt) |
---|
1127 | { |
---|
1128 | |
---|
1129 | getbinuptime_fromclock(bt, sysclock_active); |
---|
1130 | } |
---|
1131 | |
---|
1132 | void |
---|
1133 | getnanouptime(struct timespec *tsp) |
---|
1134 | { |
---|
1135 | |
---|
1136 | getnanouptime_fromclock(tsp, sysclock_active); |
---|
1137 | } |
---|
1138 | |
---|
1139 | void |
---|
1140 | getmicrouptime(struct timeval *tvp) |
---|
1141 | { |
---|
1142 | |
---|
1143 | getmicrouptime_fromclock(tvp, sysclock_active); |
---|
1144 | } |
---|
1145 | |
---|
1146 | void |
---|
1147 | getbintime(struct bintime *bt) |
---|
1148 | { |
---|
1149 | |
---|
1150 | getbintime_fromclock(bt, sysclock_active); |
---|
1151 | } |
---|
1152 | |
---|
1153 | void |
---|
1154 | getnanotime(struct timespec *tsp) |
---|
1155 | { |
---|
1156 | |
---|
1157 | getnanotime_fromclock(tsp, sysclock_active); |
---|
1158 | } |
---|
1159 | |
---|
1160 | void |
---|
1161 | getmicrotime(struct timeval *tvp) |
---|
1162 | { |
---|
1163 | |
---|
1164 | getmicrouptime_fromclock(tvp, sysclock_active); |
---|
1165 | } |
---|
1166 | |
---|
1167 | #endif /* FFCLOCK */ |
---|
1168 | |
---|
1169 | #ifndef __rtems__ |
---|
1170 | /* |
---|
1171 | * This is a clone of getnanotime and used for walltimestamps. |
---|
1172 | * The dtrace_ prefix prevents fbt from creating probes for |
---|
1173 | * it so walltimestamp can be safely used in all fbt probes. |
---|
1174 | */ |
---|
1175 | void |
---|
1176 | dtrace_getnanotime(struct timespec *tsp) |
---|
1177 | { |
---|
1178 | struct timehands *th; |
---|
1179 | uint32_t gen; |
---|
1180 | |
---|
1181 | do { |
---|
1182 | th = timehands; |
---|
1183 | gen = atomic_load_acq_int(&th->th_generation); |
---|
1184 | *tsp = th->th_nanotime; |
---|
1185 | atomic_thread_fence_acq(); |
---|
1186 | } while (gen == 0 || gen != th->th_generation); |
---|
1187 | } |
---|
1188 | #endif /* __rtems__ */ |
---|
1189 | |
---|
1190 | #ifdef FFCLOCK |
---|
1191 | /* |
---|
1192 | * System clock currently providing time to the system. Modifiable via sysctl |
---|
1193 | * when the FFCLOCK option is defined. |
---|
1194 | */ |
---|
1195 | int sysclock_active = SYSCLOCK_FBCK; |
---|
1196 | #endif |
---|
1197 | |
---|
1198 | /* Internal NTP status and error estimates. */ |
---|
1199 | extern int time_status; |
---|
1200 | extern long time_esterror; |
---|
1201 | |
---|
1202 | #ifndef __rtems__ |
---|
1203 | /* |
---|
1204 | * Take a snapshot of sysclock data which can be used to compare system clocks |
---|
1205 | * and generate timestamps after the fact. |
---|
1206 | */ |
---|
1207 | void |
---|
1208 | sysclock_getsnapshot(struct sysclock_snap *clock_snap, int fast) |
---|
1209 | { |
---|
1210 | struct fbclock_info *fbi; |
---|
1211 | struct timehands *th; |
---|
1212 | struct bintime bt; |
---|
1213 | unsigned int delta, gen; |
---|
1214 | #ifdef FFCLOCK |
---|
1215 | ffcounter ffcount; |
---|
1216 | struct fftimehands *ffth; |
---|
1217 | struct ffclock_info *ffi; |
---|
1218 | struct ffclock_estimate cest; |
---|
1219 | |
---|
1220 | ffi = &clock_snap->ff_info; |
---|
1221 | #endif |
---|
1222 | |
---|
1223 | fbi = &clock_snap->fb_info; |
---|
1224 | delta = 0; |
---|
1225 | |
---|
1226 | do { |
---|
1227 | th = timehands; |
---|
1228 | gen = atomic_load_acq_int(&th->th_generation); |
---|
1229 | fbi->th_scale = th->th_scale; |
---|
1230 | fbi->tick_time = th->th_offset; |
---|
1231 | #ifdef FFCLOCK |
---|
1232 | ffth = fftimehands; |
---|
1233 | ffi->tick_time = ffth->tick_time_lerp; |
---|
1234 | ffi->tick_time_lerp = ffth->tick_time_lerp; |
---|
1235 | ffi->period = ffth->cest.period; |
---|
1236 | ffi->period_lerp = ffth->period_lerp; |
---|
1237 | clock_snap->ffcount = ffth->tick_ffcount; |
---|
1238 | cest = ffth->cest; |
---|
1239 | #endif |
---|
1240 | if (!fast) |
---|
1241 | delta = tc_delta(th); |
---|
1242 | atomic_thread_fence_acq(); |
---|
1243 | } while (gen == 0 || gen != th->th_generation); |
---|
1244 | |
---|
1245 | clock_snap->delta = delta; |
---|
1246 | #ifdef FFCLOCK |
---|
1247 | clock_snap->sysclock_active = sysclock_active; |
---|
1248 | #endif |
---|
1249 | |
---|
1250 | /* Record feedback clock status and error. */ |
---|
1251 | clock_snap->fb_info.status = time_status; |
---|
1252 | /* XXX: Very crude estimate of feedback clock error. */ |
---|
1253 | bt.sec = time_esterror / 1000000; |
---|
1254 | bt.frac = ((time_esterror - bt.sec) * 1000000) * |
---|
1255 | (uint64_t)18446744073709ULL; |
---|
1256 | clock_snap->fb_info.error = bt; |
---|
1257 | |
---|
1258 | #ifdef FFCLOCK |
---|
1259 | if (!fast) |
---|
1260 | clock_snap->ffcount += delta; |
---|
1261 | |
---|
1262 | /* Record feed-forward clock leap second adjustment. */ |
---|
1263 | ffi->leapsec_adjustment = cest.leapsec_total; |
---|
1264 | if (clock_snap->ffcount > cest.leapsec_next) |
---|
1265 | ffi->leapsec_adjustment -= cest.leapsec; |
---|
1266 | |
---|
1267 | /* Record feed-forward clock status and error. */ |
---|
1268 | clock_snap->ff_info.status = cest.status; |
---|
1269 | ffcount = clock_snap->ffcount - cest.update_ffcount; |
---|
1270 | ffclock_convert_delta(ffcount, cest.period, &bt); |
---|
1271 | /* 18446744073709 = int(2^64/1e12), err_bound_rate in [ps/s]. */ |
---|
1272 | bintime_mul(&bt, cest.errb_rate * (uint64_t)18446744073709ULL); |
---|
1273 | /* 18446744073 = int(2^64 / 1e9), since err_abs in [ns]. */ |
---|
1274 | bintime_addx(&bt, cest.errb_abs * (uint64_t)18446744073ULL); |
---|
1275 | clock_snap->ff_info.error = bt; |
---|
1276 | #endif |
---|
1277 | } |
---|
1278 | |
---|
1279 | /* |
---|
1280 | * Convert a sysclock snapshot into a struct bintime based on the specified |
---|
1281 | * clock source and flags. |
---|
1282 | */ |
---|
1283 | int |
---|
1284 | sysclock_snap2bintime(struct sysclock_snap *cs, struct bintime *bt, |
---|
1285 | int whichclock, uint32_t flags) |
---|
1286 | { |
---|
1287 | struct bintime boottimebin; |
---|
1288 | #ifdef FFCLOCK |
---|
1289 | struct bintime bt2; |
---|
1290 | uint64_t period; |
---|
1291 | #endif |
---|
1292 | |
---|
1293 | switch (whichclock) { |
---|
1294 | case SYSCLOCK_FBCK: |
---|
1295 | *bt = cs->fb_info.tick_time; |
---|
1296 | |
---|
1297 | /* If snapshot was created with !fast, delta will be >0. */ |
---|
1298 | if (cs->delta > 0) |
---|
1299 | bintime_addx(bt, cs->fb_info.th_scale * cs->delta); |
---|
1300 | |
---|
1301 | if ((flags & FBCLOCK_UPTIME) == 0) { |
---|
1302 | getboottimebin(&boottimebin); |
---|
1303 | bintime_add(bt, &boottimebin); |
---|
1304 | } |
---|
1305 | break; |
---|
1306 | #ifdef FFCLOCK |
---|
1307 | case SYSCLOCK_FFWD: |
---|
1308 | if (flags & FFCLOCK_LERP) { |
---|
1309 | *bt = cs->ff_info.tick_time_lerp; |
---|
1310 | period = cs->ff_info.period_lerp; |
---|
1311 | } else { |
---|
1312 | *bt = cs->ff_info.tick_time; |
---|
1313 | period = cs->ff_info.period; |
---|
1314 | } |
---|
1315 | |
---|
1316 | /* If snapshot was created with !fast, delta will be >0. */ |
---|
1317 | if (cs->delta > 0) { |
---|
1318 | ffclock_convert_delta(cs->delta, period, &bt2); |
---|
1319 | bintime_add(bt, &bt2); |
---|
1320 | } |
---|
1321 | |
---|
1322 | /* Leap second adjustment. */ |
---|
1323 | if (flags & FFCLOCK_LEAPSEC) |
---|
1324 | bt->sec -= cs->ff_info.leapsec_adjustment; |
---|
1325 | |
---|
1326 | /* Boot time adjustment, for uptime/monotonic clocks. */ |
---|
1327 | if (flags & FFCLOCK_UPTIME) |
---|
1328 | bintime_sub(bt, &ffclock_boottime); |
---|
1329 | break; |
---|
1330 | #endif |
---|
1331 | default: |
---|
1332 | return (EINVAL); |
---|
1333 | break; |
---|
1334 | } |
---|
1335 | |
---|
1336 | return (0); |
---|
1337 | } |
---|
1338 | #endif /* __rtems__ */ |
---|
1339 | |
---|
1340 | /* |
---|
1341 | * Initialize a new timecounter and possibly use it. |
---|
1342 | */ |
---|
1343 | void |
---|
1344 | tc_init(struct timecounter *tc) |
---|
1345 | { |
---|
1346 | #ifndef __rtems__ |
---|
1347 | uint32_t u; |
---|
1348 | struct sysctl_oid *tc_root; |
---|
1349 | |
---|
1350 | u = tc->tc_frequency / tc->tc_counter_mask; |
---|
1351 | /* XXX: We need some margin here, 10% is a guess */ |
---|
1352 | u *= 11; |
---|
1353 | u /= 10; |
---|
1354 | if (u > hz && tc->tc_quality >= 0) { |
---|
1355 | tc->tc_quality = -2000; |
---|
1356 | if (bootverbose) { |
---|
1357 | printf("Timecounter \"%s\" frequency %ju Hz", |
---|
1358 | tc->tc_name, (uintmax_t)tc->tc_frequency); |
---|
1359 | printf(" -- Insufficient hz, needs at least %u\n", u); |
---|
1360 | } |
---|
1361 | } else if (tc->tc_quality >= 0 || bootverbose) { |
---|
1362 | printf("Timecounter \"%s\" frequency %ju Hz quality %d\n", |
---|
1363 | tc->tc_name, (uintmax_t)tc->tc_frequency, |
---|
1364 | tc->tc_quality); |
---|
1365 | } |
---|
1366 | |
---|
1367 | tc->tc_next = timecounters; |
---|
1368 | timecounters = tc; |
---|
1369 | /* |
---|
1370 | * Set up sysctl tree for this counter. |
---|
1371 | */ |
---|
1372 | tc_root = SYSCTL_ADD_NODE_WITH_LABEL(NULL, |
---|
1373 | SYSCTL_STATIC_CHILDREN(_kern_timecounter_tc), OID_AUTO, tc->tc_name, |
---|
1374 | CTLFLAG_RW, 0, "timecounter description", "timecounter"); |
---|
1375 | SYSCTL_ADD_UINT(NULL, SYSCTL_CHILDREN(tc_root), OID_AUTO, |
---|
1376 | "mask", CTLFLAG_RD, &(tc->tc_counter_mask), 0, |
---|
1377 | "mask for implemented bits"); |
---|
1378 | SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(tc_root), OID_AUTO, |
---|
1379 | "counter", CTLTYPE_UINT | CTLFLAG_RD, tc, sizeof(*tc), |
---|
1380 | sysctl_kern_timecounter_get, "IU", "current timecounter value"); |
---|
1381 | SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(tc_root), OID_AUTO, |
---|
1382 | "frequency", CTLTYPE_U64 | CTLFLAG_RD, tc, sizeof(*tc), |
---|
1383 | sysctl_kern_timecounter_freq, "QU", "timecounter frequency"); |
---|
1384 | SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(tc_root), OID_AUTO, |
---|
1385 | "quality", CTLFLAG_RD, &(tc->tc_quality), 0, |
---|
1386 | "goodness of time counter"); |
---|
1387 | /* |
---|
1388 | * Do not automatically switch if the current tc was specifically |
---|
1389 | * chosen. Never automatically use a timecounter with negative quality. |
---|
1390 | * Even though we run on the dummy counter, switching here may be |
---|
1391 | * worse since this timecounter may not be monotonic. |
---|
1392 | */ |
---|
1393 | if (tc_chosen) |
---|
1394 | return; |
---|
1395 | if (tc->tc_quality < 0) |
---|
1396 | return; |
---|
1397 | #endif /* __rtems__ */ |
---|
1398 | if (tc->tc_quality < timecounter->tc_quality) |
---|
1399 | return; |
---|
1400 | if (tc->tc_quality == timecounter->tc_quality && |
---|
1401 | tc->tc_frequency < timecounter->tc_frequency) |
---|
1402 | return; |
---|
1403 | #ifndef __rtems__ |
---|
1404 | (void)tc->tc_get_timecount(tc); |
---|
1405 | (void)tc->tc_get_timecount(tc); |
---|
1406 | #endif /* __rtems__ */ |
---|
1407 | timecounter = tc; |
---|
1408 | #ifdef __rtems__ |
---|
1409 | tc_windup(NULL); |
---|
1410 | #endif /* __rtems__ */ |
---|
1411 | } |
---|
1412 | |
---|
1413 | #ifndef __rtems__ |
---|
1414 | /* Report the frequency of the current timecounter. */ |
---|
1415 | uint64_t |
---|
1416 | tc_getfrequency(void) |
---|
1417 | { |
---|
1418 | |
---|
1419 | return (timehands->th_counter->tc_frequency); |
---|
1420 | } |
---|
1421 | |
---|
1422 | static bool |
---|
1423 | sleeping_on_old_rtc(struct thread *td) |
---|
1424 | { |
---|
1425 | |
---|
1426 | /* |
---|
1427 | * td_rtcgen is modified by curthread when it is running, |
---|
1428 | * and by other threads in this function. By finding the thread |
---|
1429 | * on a sleepqueue and holding the lock on the sleepqueue |
---|
1430 | * chain, we guarantee that the thread is not running and that |
---|
1431 | * modifying td_rtcgen is safe. Setting td_rtcgen to zero informs |
---|
1432 | * the thread that it was woken due to a real-time clock adjustment. |
---|
1433 | * (The declaration of td_rtcgen refers to this comment.) |
---|
1434 | */ |
---|
1435 | if (td->td_rtcgen != 0 && td->td_rtcgen != rtc_generation) { |
---|
1436 | td->td_rtcgen = 0; |
---|
1437 | return (true); |
---|
1438 | } |
---|
1439 | return (false); |
---|
1440 | } |
---|
1441 | |
---|
1442 | static struct mtx tc_setclock_mtx; |
---|
1443 | MTX_SYSINIT(tc_setclock_init, &tc_setclock_mtx, "tcsetc", MTX_SPIN); |
---|
1444 | #endif /* __rtems__ */ |
---|
1445 | |
---|
1446 | /* |
---|
1447 | * Step our concept of UTC. This is done by modifying our estimate of |
---|
1448 | * when we booted. |
---|
1449 | */ |
---|
1450 | void |
---|
1451 | #ifndef __rtems__ |
---|
1452 | tc_setclock(struct timespec *ts) |
---|
1453 | #else /* __rtems__ */ |
---|
1454 | _Timecounter_Set_clock(const struct bintime *_bt, |
---|
1455 | ISR_lock_Context *lock_context) |
---|
1456 | #endif /* __rtems__ */ |
---|
1457 | { |
---|
1458 | #ifndef __rtems__ |
---|
1459 | struct timespec tbef, taft; |
---|
1460 | #endif /* __rtems__ */ |
---|
1461 | struct bintime bt, bt2; |
---|
1462 | |
---|
1463 | #ifndef __rtems__ |
---|
1464 | timespec2bintime(ts, &bt); |
---|
1465 | nanotime(&tbef); |
---|
1466 | mtx_lock_spin(&tc_setclock_mtx); |
---|
1467 | cpu_tick_calibrate(1); |
---|
1468 | #else /* __rtems__ */ |
---|
1469 | bt = *_bt; |
---|
1470 | #endif /* __rtems__ */ |
---|
1471 | binuptime(&bt2); |
---|
1472 | bintime_sub(&bt, &bt2); |
---|
1473 | |
---|
1474 | /* XXX fiddle all the little crinkly bits around the fiords... */ |
---|
1475 | #ifndef __rtems__ |
---|
1476 | tc_windup(&bt); |
---|
1477 | mtx_unlock_spin(&tc_setclock_mtx); |
---|
1478 | |
---|
1479 | /* Avoid rtc_generation == 0, since td_rtcgen == 0 is special. */ |
---|
1480 | atomic_add_rel_int(&rtc_generation, 2); |
---|
1481 | sleepq_chains_remove_matching(sleeping_on_old_rtc); |
---|
1482 | if (timestepwarnings) { |
---|
1483 | nanotime(&taft); |
---|
1484 | log(LOG_INFO, |
---|
1485 | "Time stepped from %jd.%09ld to %jd.%09ld (%jd.%09ld)\n", |
---|
1486 | (intmax_t)tbef.tv_sec, tbef.tv_nsec, |
---|
1487 | (intmax_t)taft.tv_sec, taft.tv_nsec, |
---|
1488 | (intmax_t)ts->tv_sec, ts->tv_nsec); |
---|
1489 | } |
---|
1490 | #else /* __rtems__ */ |
---|
1491 | _Timecounter_Windup(&bt, lock_context); |
---|
1492 | #endif /* __rtems__ */ |
---|
1493 | } |
---|
1494 | |
---|
1495 | /* |
---|
1496 | * Initialize the next struct timehands in the ring and make |
---|
1497 | * it the active timehands. Along the way we might switch to a different |
---|
1498 | * timecounter and/or do seconds processing in NTP. Slightly magic. |
---|
1499 | */ |
---|
1500 | static void |
---|
1501 | tc_windup(struct bintime *new_boottimebin) |
---|
1502 | #ifdef __rtems__ |
---|
1503 | { |
---|
1504 | ISR_lock_Context lock_context; |
---|
1505 | |
---|
1506 | _Timecounter_Acquire(&lock_context); |
---|
1507 | _Timecounter_Windup(new_boottimebin, &lock_context); |
---|
1508 | } |
---|
1509 | |
---|
1510 | static void |
---|
1511 | _Timecounter_Windup(struct bintime *new_boottimebin, |
---|
1512 | ISR_lock_Context *lock_context) |
---|
1513 | #endif /* __rtems__ */ |
---|
1514 | { |
---|
1515 | struct bintime bt; |
---|
1516 | struct timehands *th, *tho; |
---|
1517 | uint64_t scale; |
---|
1518 | uint32_t delta, ncount, ogen; |
---|
1519 | int i; |
---|
1520 | time_t t; |
---|
1521 | |
---|
1522 | /* |
---|
1523 | * Make the next timehands a copy of the current one, but do |
---|
1524 | * not overwrite the generation or next pointer. While we |
---|
1525 | * update the contents, the generation must be zero. We need |
---|
1526 | * to ensure that the zero generation is visible before the |
---|
1527 | * data updates become visible, which requires release fence. |
---|
1528 | * For similar reasons, re-reading of the generation after the |
---|
1529 | * data is read should use acquire fence. |
---|
1530 | */ |
---|
1531 | tho = timehands; |
---|
1532 | #if defined(RTEMS_SMP) |
---|
1533 | th = tho->th_next; |
---|
1534 | #else |
---|
1535 | th = tho; |
---|
1536 | #endif |
---|
1537 | ogen = th->th_generation; |
---|
1538 | th->th_generation = 0; |
---|
1539 | atomic_thread_fence_rel(); |
---|
1540 | #if defined(RTEMS_SMP) |
---|
1541 | bcopy(tho, th, offsetof(struct timehands, th_generation)); |
---|
1542 | #endif |
---|
1543 | if (new_boottimebin != NULL) |
---|
1544 | th->th_boottime = *new_boottimebin; |
---|
1545 | |
---|
1546 | /* |
---|
1547 | * Capture a timecounter delta on the current timecounter and if |
---|
1548 | * changing timecounters, a counter value from the new timecounter. |
---|
1549 | * Update the offset fields accordingly. |
---|
1550 | */ |
---|
1551 | delta = tc_delta(th); |
---|
1552 | if (th->th_counter != timecounter) |
---|
1553 | ncount = timecounter->tc_get_timecount(timecounter); |
---|
1554 | else |
---|
1555 | ncount = 0; |
---|
1556 | #ifdef FFCLOCK |
---|
1557 | ffclock_windup(delta); |
---|
1558 | #endif |
---|
1559 | th->th_offset_count += delta; |
---|
1560 | th->th_offset_count &= th->th_counter->tc_counter_mask; |
---|
1561 | while (delta > th->th_counter->tc_frequency) { |
---|
1562 | /* Eat complete unadjusted seconds. */ |
---|
1563 | delta -= th->th_counter->tc_frequency; |
---|
1564 | th->th_offset.sec++; |
---|
1565 | } |
---|
1566 | if ((delta > th->th_counter->tc_frequency / 2) && |
---|
1567 | (th->th_scale * delta < ((uint64_t)1 << 63))) { |
---|
1568 | /* The product th_scale * delta just barely overflows. */ |
---|
1569 | th->th_offset.sec++; |
---|
1570 | } |
---|
1571 | bintime_addx(&th->th_offset, th->th_scale * delta); |
---|
1572 | |
---|
1573 | #ifndef __rtems__ |
---|
1574 | /* |
---|
1575 | * Hardware latching timecounters may not generate interrupts on |
---|
1576 | * PPS events, so instead we poll them. There is a finite risk that |
---|
1577 | * the hardware might capture a count which is later than the one we |
---|
1578 | * got above, and therefore possibly in the next NTP second which might |
---|
1579 | * have a different rate than the current NTP second. It doesn't |
---|
1580 | * matter in practice. |
---|
1581 | */ |
---|
1582 | if (tho->th_counter->tc_poll_pps) |
---|
1583 | tho->th_counter->tc_poll_pps(tho->th_counter); |
---|
1584 | #endif /* __rtems__ */ |
---|
1585 | |
---|
1586 | /* |
---|
1587 | * Deal with NTP second processing. The for loop normally |
---|
1588 | * iterates at most once, but in extreme situations it might |
---|
1589 | * keep NTP sane if timeouts are not run for several seconds. |
---|
1590 | * At boot, the time step can be large when the TOD hardware |
---|
1591 | * has been read, so on really large steps, we call |
---|
1592 | * ntp_update_second only twice. We need to call it twice in |
---|
1593 | * case we missed a leap second. |
---|
1594 | */ |
---|
1595 | bt = th->th_offset; |
---|
1596 | bintime_add(&bt, &th->th_boottime); |
---|
1597 | i = bt.sec - tho->th_microtime.tv_sec; |
---|
1598 | if (i > LARGE_STEP) |
---|
1599 | i = 2; |
---|
1600 | for (; i > 0; i--) { |
---|
1601 | t = bt.sec; |
---|
1602 | ntp_update_second(&th->th_adjustment, &bt.sec); |
---|
1603 | if (bt.sec != t) |
---|
1604 | th->th_boottime.sec += bt.sec - t; |
---|
1605 | } |
---|
1606 | /* Update the UTC timestamps used by the get*() functions. */ |
---|
1607 | th->th_bintime = bt; |
---|
1608 | bintime2timeval(&bt, &th->th_microtime); |
---|
1609 | bintime2timespec(&bt, &th->th_nanotime); |
---|
1610 | |
---|
1611 | /* Now is a good time to change timecounters. */ |
---|
1612 | if (th->th_counter != timecounter) { |
---|
1613 | #ifndef __rtems__ |
---|
1614 | #ifndef __arm__ |
---|
1615 | if ((timecounter->tc_flags & TC_FLAGS_C2STOP) != 0) |
---|
1616 | cpu_disable_c2_sleep++; |
---|
1617 | if ((th->th_counter->tc_flags & TC_FLAGS_C2STOP) != 0) |
---|
1618 | cpu_disable_c2_sleep--; |
---|
1619 | #endif |
---|
1620 | #endif /* __rtems__ */ |
---|
1621 | th->th_counter = timecounter; |
---|
1622 | th->th_offset_count = ncount; |
---|
1623 | #ifndef __rtems__ |
---|
1624 | tc_min_ticktock_freq = max(1, timecounter->tc_frequency / |
---|
1625 | (((uint64_t)timecounter->tc_counter_mask + 1) / 3)); |
---|
1626 | #endif /* __rtems__ */ |
---|
1627 | #ifdef FFCLOCK |
---|
1628 | ffclock_change_tc(th); |
---|
1629 | #endif |
---|
1630 | } |
---|
1631 | |
---|
1632 | /*- |
---|
1633 | * Recalculate the scaling factor. We want the number of 1/2^64 |
---|
1634 | * fractions of a second per period of the hardware counter, taking |
---|
1635 | * into account the th_adjustment factor which the NTP PLL/adjtime(2) |
---|
1636 | * processing provides us with. |
---|
1637 | * |
---|
1638 | * The th_adjustment is nanoseconds per second with 32 bit binary |
---|
1639 | * fraction and we want 64 bit binary fraction of second: |
---|
1640 | * |
---|
1641 | * x = a * 2^32 / 10^9 = a * 4.294967296 |
---|
1642 | * |
---|
1643 | * The range of th_adjustment is +/- 5000PPM so inside a 64bit int |
---|
1644 | * we can only multiply by about 850 without overflowing, that |
---|
1645 | * leaves no suitably precise fractions for multiply before divide. |
---|
1646 | * |
---|
1647 | * Divide before multiply with a fraction of 2199/512 results in a |
---|
1648 | * systematic undercompensation of 10PPM of th_adjustment. On a |
---|
1649 | * 5000PPM adjustment this is a 0.05PPM error. This is acceptable. |
---|
1650 | * |
---|
1651 | * We happily sacrifice the lowest of the 64 bits of our result |
---|
1652 | * to the goddess of code clarity. |
---|
1653 | * |
---|
1654 | */ |
---|
1655 | scale = (uint64_t)1 << 63; |
---|
1656 | scale += (th->th_adjustment / 1024) * 2199; |
---|
1657 | scale /= th->th_counter->tc_frequency; |
---|
1658 | th->th_scale = scale * 2; |
---|
1659 | |
---|
1660 | /* |
---|
1661 | * Now that the struct timehands is again consistent, set the new |
---|
1662 | * generation number, making sure to not make it zero. |
---|
1663 | */ |
---|
1664 | if (++ogen == 0) |
---|
1665 | ogen = 1; |
---|
1666 | atomic_store_rel_int(&th->th_generation, ogen); |
---|
1667 | |
---|
1668 | /* Go live with the new struct timehands. */ |
---|
1669 | #ifdef FFCLOCK |
---|
1670 | switch (sysclock_active) { |
---|
1671 | case SYSCLOCK_FBCK: |
---|
1672 | #endif |
---|
1673 | time_second = th->th_microtime.tv_sec; |
---|
1674 | time_uptime = th->th_offset.sec; |
---|
1675 | #ifdef FFCLOCK |
---|
1676 | break; |
---|
1677 | case SYSCLOCK_FFWD: |
---|
1678 | time_second = fftimehands->tick_time_lerp.sec; |
---|
1679 | time_uptime = fftimehands->tick_time_lerp.sec - ffclock_boottime.sec; |
---|
1680 | break; |
---|
1681 | } |
---|
1682 | #endif |
---|
1683 | |
---|
1684 | #if defined(RTEMS_SMP) |
---|
1685 | timehands = th; |
---|
1686 | #endif |
---|
1687 | #ifndef __rtems__ |
---|
1688 | timekeep_push_vdso(); |
---|
1689 | #endif /* __rtems__ */ |
---|
1690 | #ifdef __rtems__ |
---|
1691 | _Timecounter_Release(lock_context); |
---|
1692 | #endif /* __rtems__ */ |
---|
1693 | } |
---|
1694 | |
---|
1695 | #ifndef __rtems__ |
---|
1696 | /* Report or change the active timecounter hardware. */ |
---|
1697 | static int |
---|
1698 | sysctl_kern_timecounter_hardware(SYSCTL_HANDLER_ARGS) |
---|
1699 | { |
---|
1700 | char newname[32]; |
---|
1701 | struct timecounter *newtc, *tc; |
---|
1702 | int error; |
---|
1703 | |
---|
1704 | tc = timecounter; |
---|
1705 | strlcpy(newname, tc->tc_name, sizeof(newname)); |
---|
1706 | |
---|
1707 | error = sysctl_handle_string(oidp, &newname[0], sizeof(newname), req); |
---|
1708 | if (error != 0 || req->newptr == NULL) |
---|
1709 | return (error); |
---|
1710 | /* Record that the tc in use now was specifically chosen. */ |
---|
1711 | tc_chosen = 1; |
---|
1712 | if (strcmp(newname, tc->tc_name) == 0) |
---|
1713 | return (0); |
---|
1714 | for (newtc = timecounters; newtc != NULL; newtc = newtc->tc_next) { |
---|
1715 | if (strcmp(newname, newtc->tc_name) != 0) |
---|
1716 | continue; |
---|
1717 | |
---|
1718 | /* Warm up new timecounter. */ |
---|
1719 | (void)newtc->tc_get_timecount(newtc); |
---|
1720 | (void)newtc->tc_get_timecount(newtc); |
---|
1721 | |
---|
1722 | timecounter = newtc; |
---|
1723 | |
---|
1724 | /* |
---|
1725 | * The vdso timehands update is deferred until the next |
---|
1726 | * 'tc_windup()'. |
---|
1727 | * |
---|
1728 | * This is prudent given that 'timekeep_push_vdso()' does not |
---|
1729 | * use any locking and that it can be called in hard interrupt |
---|
1730 | * context via 'tc_windup()'. |
---|
1731 | */ |
---|
1732 | return (0); |
---|
1733 | } |
---|
1734 | return (EINVAL); |
---|
1735 | } |
---|
1736 | |
---|
1737 | SYSCTL_PROC(_kern_timecounter, OID_AUTO, hardware, CTLTYPE_STRING | CTLFLAG_RW, |
---|
1738 | 0, 0, sysctl_kern_timecounter_hardware, "A", |
---|
1739 | "Timecounter hardware selected"); |
---|
1740 | |
---|
1741 | |
---|
1742 | /* Report the available timecounter hardware. */ |
---|
1743 | static int |
---|
1744 | sysctl_kern_timecounter_choice(SYSCTL_HANDLER_ARGS) |
---|
1745 | { |
---|
1746 | struct sbuf sb; |
---|
1747 | struct timecounter *tc; |
---|
1748 | int error; |
---|
1749 | |
---|
1750 | sbuf_new_for_sysctl(&sb, NULL, 0, req); |
---|
1751 | for (tc = timecounters; tc != NULL; tc = tc->tc_next) { |
---|
1752 | if (tc != timecounters) |
---|
1753 | sbuf_putc(&sb, ' '); |
---|
1754 | sbuf_printf(&sb, "%s(%d)", tc->tc_name, tc->tc_quality); |
---|
1755 | } |
---|
1756 | error = sbuf_finish(&sb); |
---|
1757 | sbuf_delete(&sb); |
---|
1758 | return (error); |
---|
1759 | } |
---|
1760 | |
---|
1761 | SYSCTL_PROC(_kern_timecounter, OID_AUTO, choice, CTLTYPE_STRING | CTLFLAG_RD, |
---|
1762 | 0, 0, sysctl_kern_timecounter_choice, "A", "Timecounter hardware detected"); |
---|
1763 | #endif /* __rtems__ */ |
---|
1764 | |
---|
1765 | #ifndef __rtems__ |
---|
1766 | /* |
---|
1767 | * RFC 2783 PPS-API implementation. |
---|
1768 | */ |
---|
1769 | |
---|
1770 | /* |
---|
1771 | * Return true if the driver is aware of the abi version extensions in the |
---|
1772 | * pps_state structure, and it supports at least the given abi version number. |
---|
1773 | */ |
---|
1774 | static inline int |
---|
1775 | abi_aware(struct pps_state *pps, int vers) |
---|
1776 | { |
---|
1777 | |
---|
1778 | return ((pps->kcmode & KCMODE_ABIFLAG) && pps->driver_abi >= vers); |
---|
1779 | } |
---|
1780 | |
---|
1781 | static int |
---|
1782 | pps_fetch(struct pps_fetch_args *fapi, struct pps_state *pps) |
---|
1783 | { |
---|
1784 | int err, timo; |
---|
1785 | pps_seq_t aseq, cseq; |
---|
1786 | struct timeval tv; |
---|
1787 | |
---|
1788 | if (fapi->tsformat && fapi->tsformat != PPS_TSFMT_TSPEC) |
---|
1789 | return (EINVAL); |
---|
1790 | |
---|
1791 | /* |
---|
1792 | * If no timeout is requested, immediately return whatever values were |
---|
1793 | * most recently captured. If timeout seconds is -1, that's a request |
---|
1794 | * to block without a timeout. WITNESS won't let us sleep forever |
---|
1795 | * without a lock (we really don't need a lock), so just repeatedly |
---|
1796 | * sleep a long time. |
---|
1797 | */ |
---|
1798 | if (fapi->timeout.tv_sec || fapi->timeout.tv_nsec) { |
---|
1799 | if (fapi->timeout.tv_sec == -1) |
---|
1800 | timo = 0x7fffffff; |
---|
1801 | else { |
---|
1802 | tv.tv_sec = fapi->timeout.tv_sec; |
---|
1803 | tv.tv_usec = fapi->timeout.tv_nsec / 1000; |
---|
1804 | timo = tvtohz(&tv); |
---|
1805 | } |
---|
1806 | aseq = pps->ppsinfo.assert_sequence; |
---|
1807 | cseq = pps->ppsinfo.clear_sequence; |
---|
1808 | while (aseq == pps->ppsinfo.assert_sequence && |
---|
1809 | cseq == pps->ppsinfo.clear_sequence) { |
---|
1810 | if (abi_aware(pps, 1) && pps->driver_mtx != NULL) { |
---|
1811 | if (pps->flags & PPSFLAG_MTX_SPIN) { |
---|
1812 | err = msleep_spin(pps, pps->driver_mtx, |
---|
1813 | "ppsfch", timo); |
---|
1814 | } else { |
---|
1815 | err = msleep(pps, pps->driver_mtx, PCATCH, |
---|
1816 | "ppsfch", timo); |
---|
1817 | } |
---|
1818 | } else { |
---|
1819 | err = tsleep(pps, PCATCH, "ppsfch", timo); |
---|
1820 | } |
---|
1821 | if (err == EWOULDBLOCK) { |
---|
1822 | if (fapi->timeout.tv_sec == -1) { |
---|
1823 | continue; |
---|
1824 | } else { |
---|
1825 | return (ETIMEDOUT); |
---|
1826 | } |
---|
1827 | } else if (err != 0) { |
---|
1828 | return (err); |
---|
1829 | } |
---|
1830 | } |
---|
1831 | } |
---|
1832 | |
---|
1833 | pps->ppsinfo.current_mode = pps->ppsparam.mode; |
---|
1834 | fapi->pps_info_buf = pps->ppsinfo; |
---|
1835 | |
---|
1836 | return (0); |
---|
1837 | } |
---|
1838 | |
---|
1839 | int |
---|
1840 | pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps) |
---|
1841 | { |
---|
1842 | pps_params_t *app; |
---|
1843 | struct pps_fetch_args *fapi; |
---|
1844 | #ifdef FFCLOCK |
---|
1845 | struct pps_fetch_ffc_args *fapi_ffc; |
---|
1846 | #endif |
---|
1847 | #ifdef PPS_SYNC |
---|
1848 | struct pps_kcbind_args *kapi; |
---|
1849 | #endif |
---|
1850 | |
---|
1851 | KASSERT(pps != NULL, ("NULL pps pointer in pps_ioctl")); |
---|
1852 | switch (cmd) { |
---|
1853 | case PPS_IOC_CREATE: |
---|
1854 | return (0); |
---|
1855 | case PPS_IOC_DESTROY: |
---|
1856 | return (0); |
---|
1857 | case PPS_IOC_SETPARAMS: |
---|
1858 | app = (pps_params_t *)data; |
---|
1859 | if (app->mode & ~pps->ppscap) |
---|
1860 | return (EINVAL); |
---|
1861 | #ifdef FFCLOCK |
---|
1862 | /* Ensure only a single clock is selected for ffc timestamp. */ |
---|
1863 | if ((app->mode & PPS_TSCLK_MASK) == PPS_TSCLK_MASK) |
---|
1864 | return (EINVAL); |
---|
1865 | #endif |
---|
1866 | pps->ppsparam = *app; |
---|
1867 | return (0); |
---|
1868 | case PPS_IOC_GETPARAMS: |
---|
1869 | app = (pps_params_t *)data; |
---|
1870 | *app = pps->ppsparam; |
---|
1871 | app->api_version = PPS_API_VERS_1; |
---|
1872 | return (0); |
---|
1873 | case PPS_IOC_GETCAP: |
---|
1874 | *(int*)data = pps->ppscap; |
---|
1875 | return (0); |
---|
1876 | case PPS_IOC_FETCH: |
---|
1877 | fapi = (struct pps_fetch_args *)data; |
---|
1878 | return (pps_fetch(fapi, pps)); |
---|
1879 | #ifdef FFCLOCK |
---|
1880 | case PPS_IOC_FETCH_FFCOUNTER: |
---|
1881 | fapi_ffc = (struct pps_fetch_ffc_args *)data; |
---|
1882 | if (fapi_ffc->tsformat && fapi_ffc->tsformat != |
---|
1883 | PPS_TSFMT_TSPEC) |
---|
1884 | return (EINVAL); |
---|
1885 | if (fapi_ffc->timeout.tv_sec || fapi_ffc->timeout.tv_nsec) |
---|
1886 | return (EOPNOTSUPP); |
---|
1887 | pps->ppsinfo_ffc.current_mode = pps->ppsparam.mode; |
---|
1888 | fapi_ffc->pps_info_buf_ffc = pps->ppsinfo_ffc; |
---|
1889 | /* Overwrite timestamps if feedback clock selected. */ |
---|
1890 | switch (pps->ppsparam.mode & PPS_TSCLK_MASK) { |
---|
1891 | case PPS_TSCLK_FBCK: |
---|
1892 | fapi_ffc->pps_info_buf_ffc.assert_timestamp = |
---|
1893 | pps->ppsinfo.assert_timestamp; |
---|
1894 | fapi_ffc->pps_info_buf_ffc.clear_timestamp = |
---|
1895 | pps->ppsinfo.clear_timestamp; |
---|
1896 | break; |
---|
1897 | case PPS_TSCLK_FFWD: |
---|
1898 | break; |
---|
1899 | default: |
---|
1900 | break; |
---|
1901 | } |
---|
1902 | return (0); |
---|
1903 | #endif /* FFCLOCK */ |
---|
1904 | case PPS_IOC_KCBIND: |
---|
1905 | #ifdef PPS_SYNC |
---|
1906 | kapi = (struct pps_kcbind_args *)data; |
---|
1907 | /* XXX Only root should be able to do this */ |
---|
1908 | if (kapi->tsformat && kapi->tsformat != PPS_TSFMT_TSPEC) |
---|
1909 | return (EINVAL); |
---|
1910 | if (kapi->kernel_consumer != PPS_KC_HARDPPS) |
---|
1911 | return (EINVAL); |
---|
1912 | if (kapi->edge & ~pps->ppscap) |
---|
1913 | return (EINVAL); |
---|
1914 | pps->kcmode = (kapi->edge & KCMODE_EDGEMASK) | |
---|
1915 | (pps->kcmode & KCMODE_ABIFLAG); |
---|
1916 | return (0); |
---|
1917 | #else |
---|
1918 | return (EOPNOTSUPP); |
---|
1919 | #endif |
---|
1920 | default: |
---|
1921 | return (ENOIOCTL); |
---|
1922 | } |
---|
1923 | } |
---|
1924 | |
---|
1925 | void |
---|
1926 | pps_init(struct pps_state *pps) |
---|
1927 | { |
---|
1928 | pps->ppscap |= PPS_TSFMT_TSPEC | PPS_CANWAIT; |
---|
1929 | if (pps->ppscap & PPS_CAPTUREASSERT) |
---|
1930 | pps->ppscap |= PPS_OFFSETASSERT; |
---|
1931 | if (pps->ppscap & PPS_CAPTURECLEAR) |
---|
1932 | pps->ppscap |= PPS_OFFSETCLEAR; |
---|
1933 | #ifdef FFCLOCK |
---|
1934 | pps->ppscap |= PPS_TSCLK_MASK; |
---|
1935 | #endif |
---|
1936 | pps->kcmode &= ~KCMODE_ABIFLAG; |
---|
1937 | } |
---|
1938 | |
---|
1939 | void |
---|
1940 | pps_init_abi(struct pps_state *pps) |
---|
1941 | { |
---|
1942 | |
---|
1943 | pps_init(pps); |
---|
1944 | if (pps->driver_abi > 0) { |
---|
1945 | pps->kcmode |= KCMODE_ABIFLAG; |
---|
1946 | pps->kernel_abi = PPS_ABI_VERSION; |
---|
1947 | } |
---|
1948 | } |
---|
1949 | |
---|
1950 | void |
---|
1951 | pps_capture(struct pps_state *pps) |
---|
1952 | { |
---|
1953 | struct timehands *th; |
---|
1954 | |
---|
1955 | KASSERT(pps != NULL, ("NULL pps pointer in pps_capture")); |
---|
1956 | th = timehands; |
---|
1957 | pps->capgen = atomic_load_acq_int(&th->th_generation); |
---|
1958 | pps->capth = th; |
---|
1959 | #ifdef FFCLOCK |
---|
1960 | pps->capffth = fftimehands; |
---|
1961 | #endif |
---|
1962 | pps->capcount = th->th_counter->tc_get_timecount(th->th_counter); |
---|
1963 | atomic_thread_fence_acq(); |
---|
1964 | if (pps->capgen != th->th_generation) |
---|
1965 | pps->capgen = 0; |
---|
1966 | } |
---|
1967 | |
---|
1968 | void |
---|
1969 | pps_event(struct pps_state *pps, int event) |
---|
1970 | { |
---|
1971 | struct bintime bt; |
---|
1972 | struct timespec ts, *tsp, *osp; |
---|
1973 | uint32_t tcount, *pcount; |
---|
1974 | int foff; |
---|
1975 | pps_seq_t *pseq; |
---|
1976 | #ifdef FFCLOCK |
---|
1977 | struct timespec *tsp_ffc; |
---|
1978 | pps_seq_t *pseq_ffc; |
---|
1979 | ffcounter *ffcount; |
---|
1980 | #endif |
---|
1981 | #ifdef PPS_SYNC |
---|
1982 | int fhard; |
---|
1983 | #endif |
---|
1984 | |
---|
1985 | KASSERT(pps != NULL, ("NULL pps pointer in pps_event")); |
---|
1986 | /* Nothing to do if not currently set to capture this event type. */ |
---|
1987 | if ((event & pps->ppsparam.mode) == 0) |
---|
1988 | return; |
---|
1989 | /* If the timecounter was wound up underneath us, bail out. */ |
---|
1990 | if (pps->capgen == 0 || pps->capgen != |
---|
1991 | atomic_load_acq_int(&pps->capth->th_generation)) |
---|
1992 | return; |
---|
1993 | |
---|
1994 | /* Things would be easier with arrays. */ |
---|
1995 | if (event == PPS_CAPTUREASSERT) { |
---|
1996 | tsp = &pps->ppsinfo.assert_timestamp; |
---|
1997 | osp = &pps->ppsparam.assert_offset; |
---|
1998 | foff = pps->ppsparam.mode & PPS_OFFSETASSERT; |
---|
1999 | #ifdef PPS_SYNC |
---|
2000 | fhard = pps->kcmode & PPS_CAPTUREASSERT; |
---|
2001 | #endif |
---|
2002 | pcount = &pps->ppscount[0]; |
---|
2003 | pseq = &pps->ppsinfo.assert_sequence; |
---|
2004 | #ifdef FFCLOCK |
---|
2005 | ffcount = &pps->ppsinfo_ffc.assert_ffcount; |
---|
2006 | tsp_ffc = &pps->ppsinfo_ffc.assert_timestamp; |
---|
2007 | pseq_ffc = &pps->ppsinfo_ffc.assert_sequence; |
---|
2008 | #endif |
---|
2009 | } else { |
---|
2010 | tsp = &pps->ppsinfo.clear_timestamp; |
---|
2011 | osp = &pps->ppsparam.clear_offset; |
---|
2012 | foff = pps->ppsparam.mode & PPS_OFFSETCLEAR; |
---|
2013 | #ifdef PPS_SYNC |
---|
2014 | fhard = pps->kcmode & PPS_CAPTURECLEAR; |
---|
2015 | #endif |
---|
2016 | pcount = &pps->ppscount[1]; |
---|
2017 | pseq = &pps->ppsinfo.clear_sequence; |
---|
2018 | #ifdef FFCLOCK |
---|
2019 | ffcount = &pps->ppsinfo_ffc.clear_ffcount; |
---|
2020 | tsp_ffc = &pps->ppsinfo_ffc.clear_timestamp; |
---|
2021 | pseq_ffc = &pps->ppsinfo_ffc.clear_sequence; |
---|
2022 | #endif |
---|
2023 | } |
---|
2024 | |
---|
2025 | /* |
---|
2026 | * If the timecounter changed, we cannot compare the count values, so |
---|
2027 | * we have to drop the rest of the PPS-stuff until the next event. |
---|
2028 | */ |
---|
2029 | if (pps->ppstc != pps->capth->th_counter) { |
---|
2030 | pps->ppstc = pps->capth->th_counter; |
---|
2031 | *pcount = pps->capcount; |
---|
2032 | pps->ppscount[2] = pps->capcount; |
---|
2033 | return; |
---|
2034 | } |
---|
2035 | |
---|
2036 | /* Convert the count to a timespec. */ |
---|
2037 | tcount = pps->capcount - pps->capth->th_offset_count; |
---|
2038 | tcount &= pps->capth->th_counter->tc_counter_mask; |
---|
2039 | bt = pps->capth->th_bintime; |
---|
2040 | bintime_addx(&bt, pps->capth->th_scale * tcount); |
---|
2041 | bintime2timespec(&bt, &ts); |
---|
2042 | |
---|
2043 | /* If the timecounter was wound up underneath us, bail out. */ |
---|
2044 | atomic_thread_fence_acq(); |
---|
2045 | if (pps->capgen != pps->capth->th_generation) |
---|
2046 | return; |
---|
2047 | |
---|
2048 | *pcount = pps->capcount; |
---|
2049 | (*pseq)++; |
---|
2050 | *tsp = ts; |
---|
2051 | |
---|
2052 | if (foff) { |
---|
2053 | timespecadd(tsp, osp, tsp); |
---|
2054 | if (tsp->tv_nsec < 0) { |
---|
2055 | tsp->tv_nsec += 1000000000; |
---|
2056 | tsp->tv_sec -= 1; |
---|
2057 | } |
---|
2058 | } |
---|
2059 | |
---|
2060 | #ifdef FFCLOCK |
---|
2061 | *ffcount = pps->capffth->tick_ffcount + tcount; |
---|
2062 | bt = pps->capffth->tick_time; |
---|
2063 | ffclock_convert_delta(tcount, pps->capffth->cest.period, &bt); |
---|
2064 | bintime_add(&bt, &pps->capffth->tick_time); |
---|
2065 | bintime2timespec(&bt, &ts); |
---|
2066 | (*pseq_ffc)++; |
---|
2067 | *tsp_ffc = ts; |
---|
2068 | #endif |
---|
2069 | |
---|
2070 | #ifdef PPS_SYNC |
---|
2071 | if (fhard) { |
---|
2072 | uint64_t scale; |
---|
2073 | |
---|
2074 | /* |
---|
2075 | * Feed the NTP PLL/FLL. |
---|
2076 | * The FLL wants to know how many (hardware) nanoseconds |
---|
2077 | * elapsed since the previous event. |
---|
2078 | */ |
---|
2079 | tcount = pps->capcount - pps->ppscount[2]; |
---|
2080 | pps->ppscount[2] = pps->capcount; |
---|
2081 | tcount &= pps->capth->th_counter->tc_counter_mask; |
---|
2082 | scale = (uint64_t)1 << 63; |
---|
2083 | scale /= pps->capth->th_counter->tc_frequency; |
---|
2084 | scale *= 2; |
---|
2085 | bt.sec = 0; |
---|
2086 | bt.frac = 0; |
---|
2087 | bintime_addx(&bt, scale * tcount); |
---|
2088 | bintime2timespec(&bt, &ts); |
---|
2089 | hardpps(tsp, ts.tv_nsec + 1000000000 * ts.tv_sec); |
---|
2090 | } |
---|
2091 | #endif |
---|
2092 | |
---|
2093 | /* Wakeup anyone sleeping in pps_fetch(). */ |
---|
2094 | wakeup(pps); |
---|
2095 | } |
---|
2096 | #else /* __rtems__ */ |
---|
2097 | /* FIXME: https://devel.rtems.org/ticket/2349 */ |
---|
2098 | #endif /* __rtems__ */ |
---|
2099 | |
---|
2100 | /* |
---|
2101 | * Timecounters need to be updated every so often to prevent the hardware |
---|
2102 | * counter from overflowing. Updating also recalculates the cached values |
---|
2103 | * used by the get*() family of functions, so their precision depends on |
---|
2104 | * the update frequency. |
---|
2105 | */ |
---|
2106 | |
---|
2107 | #ifndef __rtems__ |
---|
2108 | static int tc_tick; |
---|
2109 | SYSCTL_INT(_kern_timecounter, OID_AUTO, tick, CTLFLAG_RD, &tc_tick, 0, |
---|
2110 | "Approximate number of hardclock ticks in a millisecond"); |
---|
2111 | #endif /* __rtems__ */ |
---|
2112 | |
---|
2113 | #ifndef __rtems__ |
---|
2114 | void |
---|
2115 | tc_ticktock(int cnt) |
---|
2116 | { |
---|
2117 | static int count; |
---|
2118 | |
---|
2119 | if (mtx_trylock_spin(&tc_setclock_mtx)) { |
---|
2120 | count += cnt; |
---|
2121 | if (count >= tc_tick) { |
---|
2122 | count = 0; |
---|
2123 | tc_windup(NULL); |
---|
2124 | } |
---|
2125 | mtx_unlock_spin(&tc_setclock_mtx); |
---|
2126 | } |
---|
2127 | } |
---|
2128 | #else /* __rtems__ */ |
---|
2129 | void |
---|
2130 | _Timecounter_Tick(void) |
---|
2131 | { |
---|
2132 | Per_CPU_Control *cpu_self = _Per_CPU_Get(); |
---|
2133 | |
---|
2134 | if (_Per_CPU_Is_boot_processor(cpu_self)) { |
---|
2135 | tc_windup(NULL); |
---|
2136 | } |
---|
2137 | |
---|
2138 | _Watchdog_Tick(cpu_self); |
---|
2139 | } |
---|
2140 | |
---|
2141 | void |
---|
2142 | _Timecounter_Tick_simple(uint32_t delta, uint32_t offset, |
---|
2143 | ISR_lock_Context *lock_context) |
---|
2144 | { |
---|
2145 | struct bintime bt; |
---|
2146 | struct timehands *th; |
---|
2147 | uint32_t ogen; |
---|
2148 | |
---|
2149 | th = timehands; |
---|
2150 | ogen = th->th_generation; |
---|
2151 | th->th_offset_count = offset; |
---|
2152 | bintime_addx(&th->th_offset, th->th_scale * delta); |
---|
2153 | |
---|
2154 | bt = th->th_offset; |
---|
2155 | bintime_add(&bt, &th->th_boottime); |
---|
2156 | /* Update the UTC timestamps used by the get*() functions. */ |
---|
2157 | th->th_bintime = bt; |
---|
2158 | bintime2timeval(&bt, &th->th_microtime); |
---|
2159 | bintime2timespec(&bt, &th->th_nanotime); |
---|
2160 | |
---|
2161 | /* |
---|
2162 | * Now that the struct timehands is again consistent, set the new |
---|
2163 | * generation number, making sure to not make it zero. |
---|
2164 | */ |
---|
2165 | if (++ogen == 0) |
---|
2166 | ogen = 1; |
---|
2167 | th->th_generation = ogen; |
---|
2168 | |
---|
2169 | /* Go live with the new struct timehands. */ |
---|
2170 | time_second = th->th_microtime.tv_sec; |
---|
2171 | time_uptime = th->th_offset.sec; |
---|
2172 | |
---|
2173 | _Timecounter_Release(lock_context); |
---|
2174 | |
---|
2175 | _Watchdog_Tick(_Per_CPU_Get_snapshot()); |
---|
2176 | } |
---|
2177 | #endif /* __rtems__ */ |
---|
2178 | |
---|
2179 | #ifndef __rtems__ |
---|
2180 | static void __inline |
---|
2181 | tc_adjprecision(void) |
---|
2182 | { |
---|
2183 | int t; |
---|
2184 | |
---|
2185 | if (tc_timepercentage > 0) { |
---|
2186 | t = (99 + tc_timepercentage) / tc_timepercentage; |
---|
2187 | tc_precexp = fls(t + (t >> 1)) - 1; |
---|
2188 | FREQ2BT(hz / tc_tick, &bt_timethreshold); |
---|
2189 | FREQ2BT(hz, &bt_tickthreshold); |
---|
2190 | bintime_shift(&bt_timethreshold, tc_precexp); |
---|
2191 | bintime_shift(&bt_tickthreshold, tc_precexp); |
---|
2192 | } else { |
---|
2193 | tc_precexp = 31; |
---|
2194 | bt_timethreshold.sec = INT_MAX; |
---|
2195 | bt_timethreshold.frac = ~(uint64_t)0; |
---|
2196 | bt_tickthreshold = bt_timethreshold; |
---|
2197 | } |
---|
2198 | sbt_timethreshold = bttosbt(bt_timethreshold); |
---|
2199 | sbt_tickthreshold = bttosbt(bt_tickthreshold); |
---|
2200 | } |
---|
2201 | #endif /* __rtems__ */ |
---|
2202 | |
---|
2203 | #ifndef __rtems__ |
---|
2204 | static int |
---|
2205 | sysctl_kern_timecounter_adjprecision(SYSCTL_HANDLER_ARGS) |
---|
2206 | { |
---|
2207 | int error, val; |
---|
2208 | |
---|
2209 | val = tc_timepercentage; |
---|
2210 | error = sysctl_handle_int(oidp, &val, 0, req); |
---|
2211 | if (error != 0 || req->newptr == NULL) |
---|
2212 | return (error); |
---|
2213 | tc_timepercentage = val; |
---|
2214 | if (cold) |
---|
2215 | goto done; |
---|
2216 | tc_adjprecision(); |
---|
2217 | done: |
---|
2218 | return (0); |
---|
2219 | } |
---|
2220 | |
---|
2221 | static void |
---|
2222 | inittimecounter(void *dummy) |
---|
2223 | { |
---|
2224 | u_int p; |
---|
2225 | int tick_rate; |
---|
2226 | |
---|
2227 | /* |
---|
2228 | * Set the initial timeout to |
---|
2229 | * max(1, <approx. number of hardclock ticks in a millisecond>). |
---|
2230 | * People should probably not use the sysctl to set the timeout |
---|
2231 | * to smaller than its initial value, since that value is the |
---|
2232 | * smallest reasonable one. If they want better timestamps they |
---|
2233 | * should use the non-"get"* functions. |
---|
2234 | */ |
---|
2235 | if (hz > 1000) |
---|
2236 | tc_tick = (hz + 500) / 1000; |
---|
2237 | else |
---|
2238 | tc_tick = 1; |
---|
2239 | tc_adjprecision(); |
---|
2240 | FREQ2BT(hz, &tick_bt); |
---|
2241 | tick_sbt = bttosbt(tick_bt); |
---|
2242 | tick_rate = hz / tc_tick; |
---|
2243 | FREQ2BT(tick_rate, &tc_tick_bt); |
---|
2244 | tc_tick_sbt = bttosbt(tc_tick_bt); |
---|
2245 | p = (tc_tick * 1000000) / hz; |
---|
2246 | printf("Timecounters tick every %d.%03u msec\n", p / 1000, p % 1000); |
---|
2247 | |
---|
2248 | #ifdef FFCLOCK |
---|
2249 | ffclock_init(); |
---|
2250 | #endif |
---|
2251 | /* warm up new timecounter (again) and get rolling. */ |
---|
2252 | (void)timecounter->tc_get_timecount(timecounter); |
---|
2253 | (void)timecounter->tc_get_timecount(timecounter); |
---|
2254 | mtx_lock_spin(&tc_setclock_mtx); |
---|
2255 | tc_windup(NULL); |
---|
2256 | mtx_unlock_spin(&tc_setclock_mtx); |
---|
2257 | } |
---|
2258 | |
---|
2259 | SYSINIT(timecounter, SI_SUB_CLOCKS, SI_ORDER_SECOND, inittimecounter, NULL); |
---|
2260 | |
---|
2261 | /* Cpu tick handling -------------------------------------------------*/ |
---|
2262 | |
---|
2263 | static int cpu_tick_variable; |
---|
2264 | static uint64_t cpu_tick_frequency; |
---|
2265 | |
---|
2266 | static DPCPU_DEFINE(uint64_t, tc_cpu_ticks_base); |
---|
2267 | static DPCPU_DEFINE(unsigned, tc_cpu_ticks_last); |
---|
2268 | |
---|
2269 | static uint64_t |
---|
2270 | tc_cpu_ticks(void) |
---|
2271 | { |
---|
2272 | struct timecounter *tc; |
---|
2273 | uint64_t res, *base; |
---|
2274 | unsigned u, *last; |
---|
2275 | |
---|
2276 | critical_enter(); |
---|
2277 | base = DPCPU_PTR(tc_cpu_ticks_base); |
---|
2278 | last = DPCPU_PTR(tc_cpu_ticks_last); |
---|
2279 | tc = timehands->th_counter; |
---|
2280 | u = tc->tc_get_timecount(tc) & tc->tc_counter_mask; |
---|
2281 | if (u < *last) |
---|
2282 | *base += (uint64_t)tc->tc_counter_mask + 1; |
---|
2283 | *last = u; |
---|
2284 | res = u + *base; |
---|
2285 | critical_exit(); |
---|
2286 | return (res); |
---|
2287 | } |
---|
2288 | |
---|
2289 | void |
---|
2290 | cpu_tick_calibration(void) |
---|
2291 | { |
---|
2292 | static time_t last_calib; |
---|
2293 | |
---|
2294 | if (time_uptime != last_calib && !(time_uptime & 0xf)) { |
---|
2295 | cpu_tick_calibrate(0); |
---|
2296 | last_calib = time_uptime; |
---|
2297 | } |
---|
2298 | } |
---|
2299 | |
---|
2300 | /* |
---|
2301 | * This function gets called every 16 seconds on only one designated |
---|
2302 | * CPU in the system from hardclock() via cpu_tick_calibration()(). |
---|
2303 | * |
---|
2304 | * Whenever the real time clock is stepped we get called with reset=1 |
---|
2305 | * to make sure we handle suspend/resume and similar events correctly. |
---|
2306 | */ |
---|
2307 | |
---|
2308 | static void |
---|
2309 | cpu_tick_calibrate(int reset) |
---|
2310 | { |
---|
2311 | static uint64_t c_last; |
---|
2312 | uint64_t c_this, c_delta; |
---|
2313 | static struct bintime t_last; |
---|
2314 | struct bintime t_this, t_delta; |
---|
2315 | uint32_t divi; |
---|
2316 | |
---|
2317 | if (reset) { |
---|
2318 | /* The clock was stepped, abort & reset */ |
---|
2319 | t_last.sec = 0; |
---|
2320 | return; |
---|
2321 | } |
---|
2322 | |
---|
2323 | /* we don't calibrate fixed rate cputicks */ |
---|
2324 | if (!cpu_tick_variable) |
---|
2325 | return; |
---|
2326 | |
---|
2327 | getbinuptime(&t_this); |
---|
2328 | c_this = cpu_ticks(); |
---|
2329 | if (t_last.sec != 0) { |
---|
2330 | c_delta = c_this - c_last; |
---|
2331 | t_delta = t_this; |
---|
2332 | bintime_sub(&t_delta, &t_last); |
---|
2333 | /* |
---|
2334 | * Headroom: |
---|
2335 | * 2^(64-20) / 16[s] = |
---|
2336 | * 2^(44) / 16[s] = |
---|
2337 | * 17.592.186.044.416 / 16 = |
---|
2338 | * 1.099.511.627.776 [Hz] |
---|
2339 | */ |
---|
2340 | divi = t_delta.sec << 20; |
---|
2341 | divi |= t_delta.frac >> (64 - 20); |
---|
2342 | c_delta <<= 20; |
---|
2343 | c_delta /= divi; |
---|
2344 | if (c_delta > cpu_tick_frequency) { |
---|
2345 | if (0 && bootverbose) |
---|
2346 | printf("cpu_tick increased to %ju Hz\n", |
---|
2347 | c_delta); |
---|
2348 | cpu_tick_frequency = c_delta; |
---|
2349 | } |
---|
2350 | } |
---|
2351 | c_last = c_this; |
---|
2352 | t_last = t_this; |
---|
2353 | } |
---|
2354 | |
---|
2355 | void |
---|
2356 | set_cputicker(cpu_tick_f *func, uint64_t freq, unsigned var) |
---|
2357 | { |
---|
2358 | |
---|
2359 | if (func == NULL) { |
---|
2360 | cpu_ticks = tc_cpu_ticks; |
---|
2361 | } else { |
---|
2362 | cpu_tick_frequency = freq; |
---|
2363 | cpu_tick_variable = var; |
---|
2364 | cpu_ticks = func; |
---|
2365 | } |
---|
2366 | } |
---|
2367 | |
---|
2368 | uint64_t |
---|
2369 | cpu_tickrate(void) |
---|
2370 | { |
---|
2371 | |
---|
2372 | if (cpu_ticks == tc_cpu_ticks) |
---|
2373 | return (tc_getfrequency()); |
---|
2374 | return (cpu_tick_frequency); |
---|
2375 | } |
---|
2376 | |
---|
2377 | /* |
---|
2378 | * We need to be slightly careful converting cputicks to microseconds. |
---|
2379 | * There is plenty of margin in 64 bits of microseconds (half a million |
---|
2380 | * years) and in 64 bits at 4 GHz (146 years), but if we do a multiply |
---|
2381 | * before divide conversion (to retain precision) we find that the |
---|
2382 | * margin shrinks to 1.5 hours (one millionth of 146y). |
---|
2383 | * With a three prong approach we never lose significant bits, no |
---|
2384 | * matter what the cputick rate and length of timeinterval is. |
---|
2385 | */ |
---|
2386 | |
---|
2387 | uint64_t |
---|
2388 | cputick2usec(uint64_t tick) |
---|
2389 | { |
---|
2390 | |
---|
2391 | if (tick > 18446744073709551LL) /* floor(2^64 / 1000) */ |
---|
2392 | return (tick / (cpu_tickrate() / 1000000LL)); |
---|
2393 | else if (tick > 18446744073709LL) /* floor(2^64 / 1000000) */ |
---|
2394 | return ((tick * 1000LL) / (cpu_tickrate() / 1000LL)); |
---|
2395 | else |
---|
2396 | return ((tick * 1000000LL) / cpu_tickrate()); |
---|
2397 | } |
---|
2398 | |
---|
2399 | cpu_tick_f *cpu_ticks = tc_cpu_ticks; |
---|
2400 | #endif /* __rtems__ */ |
---|
2401 | |
---|
2402 | #ifndef __rtems__ |
---|
2403 | static int vdso_th_enable = 1; |
---|
2404 | static int |
---|
2405 | sysctl_fast_gettime(SYSCTL_HANDLER_ARGS) |
---|
2406 | { |
---|
2407 | int old_vdso_th_enable, error; |
---|
2408 | |
---|
2409 | old_vdso_th_enable = vdso_th_enable; |
---|
2410 | error = sysctl_handle_int(oidp, &old_vdso_th_enable, 0, req); |
---|
2411 | if (error != 0) |
---|
2412 | return (error); |
---|
2413 | vdso_th_enable = old_vdso_th_enable; |
---|
2414 | return (0); |
---|
2415 | } |
---|
2416 | SYSCTL_PROC(_kern_timecounter, OID_AUTO, fast_gettime, |
---|
2417 | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, |
---|
2418 | NULL, 0, sysctl_fast_gettime, "I", "Enable fast time of day"); |
---|
2419 | |
---|
2420 | uint32_t |
---|
2421 | tc_fill_vdso_timehands(struct vdso_timehands *vdso_th) |
---|
2422 | { |
---|
2423 | struct timehands *th; |
---|
2424 | uint32_t enabled; |
---|
2425 | |
---|
2426 | th = timehands; |
---|
2427 | vdso_th->th_scale = th->th_scale; |
---|
2428 | vdso_th->th_offset_count = th->th_offset_count; |
---|
2429 | vdso_th->th_counter_mask = th->th_counter->tc_counter_mask; |
---|
2430 | vdso_th->th_offset = th->th_offset; |
---|
2431 | vdso_th->th_boottime = th->th_boottime; |
---|
2432 | if (th->th_counter->tc_fill_vdso_timehands != NULL) { |
---|
2433 | enabled = th->th_counter->tc_fill_vdso_timehands(vdso_th, |
---|
2434 | th->th_counter); |
---|
2435 | } else |
---|
2436 | enabled = 0; |
---|
2437 | if (!vdso_th_enable) |
---|
2438 | enabled = 0; |
---|
2439 | return (enabled); |
---|
2440 | } |
---|
2441 | #endif /* __rtems__ */ |
---|
2442 | |
---|
2443 | #ifdef COMPAT_FREEBSD32 |
---|
2444 | uint32_t |
---|
2445 | tc_fill_vdso_timehands32(struct vdso_timehands32 *vdso_th32) |
---|
2446 | { |
---|
2447 | struct timehands *th; |
---|
2448 | uint32_t enabled; |
---|
2449 | |
---|
2450 | th = timehands; |
---|
2451 | *(uint64_t *)&vdso_th32->th_scale[0] = th->th_scale; |
---|
2452 | vdso_th32->th_offset_count = th->th_offset_count; |
---|
2453 | vdso_th32->th_counter_mask = th->th_counter->tc_counter_mask; |
---|
2454 | vdso_th32->th_offset.sec = th->th_offset.sec; |
---|
2455 | *(uint64_t *)&vdso_th32->th_offset.frac[0] = th->th_offset.frac; |
---|
2456 | vdso_th32->th_boottime.sec = th->th_boottime.sec; |
---|
2457 | *(uint64_t *)&vdso_th32->th_boottime.frac[0] = th->th_boottime.frac; |
---|
2458 | if (th->th_counter->tc_fill_vdso_timehands32 != NULL) { |
---|
2459 | enabled = th->th_counter->tc_fill_vdso_timehands32(vdso_th32, |
---|
2460 | th->th_counter); |
---|
2461 | } else |
---|
2462 | enabled = 0; |
---|
2463 | if (!vdso_th_enable) |
---|
2464 | enabled = 0; |
---|
2465 | return (enabled); |
---|
2466 | } |
---|
2467 | #endif |
---|