john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/time/timekeeping.c |
| 3 | * |
| 4 | * Kernel timekeeping code and accessor functions |
| 5 | * |
| 6 | * This code was moved from linux/kernel/timer.c. |
| 7 | * Please see that file for copyright and history logs. |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/interrupt.h> |
| 13 | #include <linux/percpu.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/mm.h> |
Alexey Dobriyan | d43c36d | 2009-10-07 17:09:06 +0400 | [diff] [blame] | 16 | #include <linux/sched.h> |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 17 | #include <linux/syscore_ops.h> |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 18 | #include <linux/clocksource.h> |
| 19 | #include <linux/jiffies.h> |
| 20 | #include <linux/time.h> |
| 21 | #include <linux/tick.h> |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 22 | #include <linux/stop_machine.h> |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 23 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 24 | /* Structure holding internal timekeeping values. */ |
| 25 | struct timekeeper { |
| 26 | /* Current clocksource used for timekeeping. */ |
| 27 | struct clocksource *clock; |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 28 | /* The shift value of the current clocksource. */ |
| 29 | int shift; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 30 | |
| 31 | /* Number of clock cycles in one NTP interval. */ |
| 32 | cycle_t cycle_interval; |
| 33 | /* Number of clock shifted nano seconds in one NTP interval. */ |
| 34 | u64 xtime_interval; |
Kasper Pedersen | a386b5a | 2010-10-20 15:55:15 -0700 | [diff] [blame] | 35 | /* shifted nano seconds left over when rounding cycle_interval */ |
| 36 | s64 xtime_remainder; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 37 | /* Raw nano seconds accumulated per NTP interval. */ |
| 38 | u32 raw_interval; |
| 39 | |
| 40 | /* Clock shifted nano seconds remainder not stored in xtime.tv_nsec. */ |
| 41 | u64 xtime_nsec; |
| 42 | /* Difference between accumulated time and NTP time in ntp |
| 43 | * shifted nano seconds. */ |
| 44 | s64 ntp_error; |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 45 | /* Shift conversion between clock shifted nano seconds and |
| 46 | * ntp shifted nano seconds. */ |
| 47 | int ntp_error_shift; |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 48 | /* NTP adjusted clock multiplier */ |
| 49 | u32 mult; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 50 | }; |
| 51 | |
H Hartley Sweeten | afa14e7 | 2011-01-11 17:59:38 -0600 | [diff] [blame] | 52 | static struct timekeeper timekeeper; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 53 | |
| 54 | /** |
| 55 | * timekeeper_setup_internals - Set up internals to use clocksource clock. |
| 56 | * |
| 57 | * @clock: Pointer to clocksource. |
| 58 | * |
| 59 | * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment |
| 60 | * pair and interval request. |
| 61 | * |
| 62 | * Unless you're the timekeeping code, you should not be using this! |
| 63 | */ |
| 64 | static void timekeeper_setup_internals(struct clocksource *clock) |
| 65 | { |
| 66 | cycle_t interval; |
Kasper Pedersen | a386b5a | 2010-10-20 15:55:15 -0700 | [diff] [blame] | 67 | u64 tmp, ntpinterval; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 68 | |
| 69 | timekeeper.clock = clock; |
| 70 | clock->cycle_last = clock->read(clock); |
| 71 | |
| 72 | /* Do the ns -> cycle conversion first, using original mult */ |
| 73 | tmp = NTP_INTERVAL_LENGTH; |
| 74 | tmp <<= clock->shift; |
Kasper Pedersen | a386b5a | 2010-10-20 15:55:15 -0700 | [diff] [blame] | 75 | ntpinterval = tmp; |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 76 | tmp += clock->mult/2; |
| 77 | do_div(tmp, clock->mult); |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 78 | if (tmp == 0) |
| 79 | tmp = 1; |
| 80 | |
| 81 | interval = (cycle_t) tmp; |
| 82 | timekeeper.cycle_interval = interval; |
| 83 | |
| 84 | /* Go back from cycles -> shifted ns */ |
| 85 | timekeeper.xtime_interval = (u64) interval * clock->mult; |
Kasper Pedersen | a386b5a | 2010-10-20 15:55:15 -0700 | [diff] [blame] | 86 | timekeeper.xtime_remainder = ntpinterval - timekeeper.xtime_interval; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 87 | timekeeper.raw_interval = |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 88 | ((u64) interval * clock->mult) >> clock->shift; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 89 | |
| 90 | timekeeper.xtime_nsec = 0; |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 91 | timekeeper.shift = clock->shift; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 92 | |
| 93 | timekeeper.ntp_error = 0; |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 94 | timekeeper.ntp_error_shift = NTP_SCALE_SHIFT - clock->shift; |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 95 | |
| 96 | /* |
| 97 | * The timekeeper keeps its own mult values for the currently |
| 98 | * active clocksource. These value will be adjusted via NTP |
| 99 | * to counteract clock drifting. |
| 100 | */ |
| 101 | timekeeper.mult = clock->mult; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 102 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 103 | |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 104 | /* Timekeeper helper functions. */ |
| 105 | static inline s64 timekeeping_get_ns(void) |
| 106 | { |
| 107 | cycle_t cycle_now, cycle_delta; |
| 108 | struct clocksource *clock; |
| 109 | |
| 110 | /* read clocksource: */ |
| 111 | clock = timekeeper.clock; |
| 112 | cycle_now = clock->read(clock); |
| 113 | |
| 114 | /* calculate the delta since the last update_wall_time: */ |
| 115 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; |
| 116 | |
| 117 | /* return delta convert to nanoseconds using ntp adjusted mult. */ |
| 118 | return clocksource_cyc2ns(cycle_delta, timekeeper.mult, |
| 119 | timekeeper.shift); |
| 120 | } |
| 121 | |
| 122 | static inline s64 timekeeping_get_ns_raw(void) |
| 123 | { |
| 124 | cycle_t cycle_now, cycle_delta; |
| 125 | struct clocksource *clock; |
| 126 | |
| 127 | /* read clocksource: */ |
| 128 | clock = timekeeper.clock; |
| 129 | cycle_now = clock->read(clock); |
| 130 | |
| 131 | /* calculate the delta since the last update_wall_time: */ |
| 132 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; |
| 133 | |
| 134 | /* return delta convert to nanoseconds using ntp adjusted mult. */ |
| 135 | return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); |
| 136 | } |
| 137 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 138 | /* |
| 139 | * This read-write spinlock protects us from races in SMP while |
Thomas Gleixner | dce48a8 | 2009-04-11 10:43:41 +0200 | [diff] [blame] | 140 | * playing with xtime. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 141 | */ |
Adrian Bunk | ba2a631 | 2007-10-16 23:27:16 -0700 | [diff] [blame] | 142 | __cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 143 | |
| 144 | |
| 145 | /* |
| 146 | * The current time |
| 147 | * wall_to_monotonic is what we need to add to xtime (or xtime corrected |
| 148 | * for sub jiffie times) to get to monotonic time. Monotonic is pegged |
| 149 | * at zero at system boot time, so wall_to_monotonic will be negative, |
| 150 | * however, we will ALWAYS keep the tv_nsec part positive so we can use |
| 151 | * the usual normalization. |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 152 | * |
| 153 | * wall_to_monotonic is moved after resume from suspend for the monotonic |
| 154 | * time not to jump. We need to add total_sleep_time to wall_to_monotonic |
| 155 | * to get the real boot based time offset. |
| 156 | * |
| 157 | * - wall_to_monotonic is no longer the boot time, getboottime must be |
| 158 | * used instead. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 159 | */ |
John Stultz | 0fb86b0 | 2010-07-13 17:56:26 -0700 | [diff] [blame] | 160 | static struct timespec xtime __attribute__ ((aligned (16))); |
| 161 | static struct timespec wall_to_monotonic __attribute__ ((aligned (16))); |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 162 | static struct timespec total_sleep_time; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 163 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 164 | /* |
| 165 | * The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. |
| 166 | */ |
H Hartley Sweeten | afa14e7 | 2011-01-11 17:59:38 -0600 | [diff] [blame] | 167 | static struct timespec raw_time; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 168 | |
Thomas Gleixner | 1c5745a | 2008-12-22 23:05:28 +0100 | [diff] [blame] | 169 | /* flag for if timekeeping is suspended */ |
| 170 | int __read_mostly timekeeping_suspended; |
| 171 | |
John Stultz | 31089c1 | 2009-08-14 15:47:18 +0200 | [diff] [blame] | 172 | /* must hold xtime_lock */ |
| 173 | void timekeeping_leap_insert(int leapsecond) |
| 174 | { |
| 175 | xtime.tv_sec += leapsecond; |
| 176 | wall_to_monotonic.tv_sec -= leapsecond; |
John Stultz | 7615856 | 2010-07-13 17:56:23 -0700 | [diff] [blame] | 177 | update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, |
| 178 | timekeeper.mult); |
John Stultz | 31089c1 | 2009-08-14 15:47:18 +0200 | [diff] [blame] | 179 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 180 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 181 | /** |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 182 | * timekeeping_forward_now - update clock to the current time |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 183 | * |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 184 | * Forward the current clock to update its state since the last call to |
| 185 | * update_wall_time(). This is useful before significant clock changes, |
| 186 | * as it avoids having to deal with this time offset explicitly. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 187 | */ |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 188 | static void timekeeping_forward_now(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 189 | { |
| 190 | cycle_t cycle_now, cycle_delta; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 191 | struct clocksource *clock; |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 192 | s64 nsec; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 193 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 194 | clock = timekeeper.clock; |
Martin Schwidefsky | a0f7d48 | 2009-08-14 15:47:19 +0200 | [diff] [blame] | 195 | cycle_now = clock->read(clock); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 196 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 197 | clock->cycle_last = cycle_now; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 198 | |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 199 | nsec = clocksource_cyc2ns(cycle_delta, timekeeper.mult, |
| 200 | timekeeper.shift); |
john stultz | 7d27558 | 2009-05-01 13:10:26 -0700 | [diff] [blame] | 201 | |
| 202 | /* If arch requires, add in gettimeoffset() */ |
| 203 | nsec += arch_gettimeoffset(); |
| 204 | |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 205 | timespec_add_ns(&xtime, nsec); |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 206 | |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 207 | nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 208 | timespec_add_ns(&raw_time, nsec); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 209 | } |
| 210 | |
| 211 | /** |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 212 | * getnstimeofday - Returns the time of day in a timespec |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 213 | * @ts: pointer to the timespec to be set |
| 214 | * |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 215 | * Returns the time of day in a timespec. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 216 | */ |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 217 | void getnstimeofday(struct timespec *ts) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 218 | { |
| 219 | unsigned long seq; |
| 220 | s64 nsecs; |
| 221 | |
Thomas Gleixner | 1c5745a | 2008-12-22 23:05:28 +0100 | [diff] [blame] | 222 | WARN_ON(timekeeping_suspended); |
| 223 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 224 | do { |
| 225 | seq = read_seqbegin(&xtime_lock); |
| 226 | |
| 227 | *ts = xtime; |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 228 | nsecs = timekeeping_get_ns(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 229 | |
john stultz | 7d27558 | 2009-05-01 13:10:26 -0700 | [diff] [blame] | 230 | /* If arch requires, add in gettimeoffset() */ |
| 231 | nsecs += arch_gettimeoffset(); |
| 232 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 233 | } while (read_seqretry(&xtime_lock, seq)); |
| 234 | |
| 235 | timespec_add_ns(ts, nsecs); |
| 236 | } |
| 237 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 238 | EXPORT_SYMBOL(getnstimeofday); |
| 239 | |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 240 | ktime_t ktime_get(void) |
| 241 | { |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 242 | unsigned int seq; |
| 243 | s64 secs, nsecs; |
| 244 | |
| 245 | WARN_ON(timekeeping_suspended); |
| 246 | |
| 247 | do { |
| 248 | seq = read_seqbegin(&xtime_lock); |
| 249 | secs = xtime.tv_sec + wall_to_monotonic.tv_sec; |
| 250 | nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec; |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 251 | nsecs += timekeeping_get_ns(); |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 252 | |
| 253 | } while (read_seqretry(&xtime_lock, seq)); |
| 254 | /* |
| 255 | * Use ktime_set/ktime_add_ns to create a proper ktime on |
| 256 | * 32-bit architectures without CONFIG_KTIME_SCALAR. |
| 257 | */ |
| 258 | return ktime_add_ns(ktime_set(secs, 0), nsecs); |
| 259 | } |
| 260 | EXPORT_SYMBOL_GPL(ktime_get); |
| 261 | |
| 262 | /** |
| 263 | * ktime_get_ts - get the monotonic clock in timespec format |
| 264 | * @ts: pointer to timespec variable |
| 265 | * |
| 266 | * The function calculates the monotonic clock from the realtime |
| 267 | * clock and the wall_to_monotonic offset and stores the result |
| 268 | * in normalized timespec format in the variable pointed to by @ts. |
| 269 | */ |
| 270 | void ktime_get_ts(struct timespec *ts) |
| 271 | { |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 272 | struct timespec tomono; |
| 273 | unsigned int seq; |
| 274 | s64 nsecs; |
| 275 | |
| 276 | WARN_ON(timekeeping_suspended); |
| 277 | |
| 278 | do { |
| 279 | seq = read_seqbegin(&xtime_lock); |
| 280 | *ts = xtime; |
| 281 | tomono = wall_to_monotonic; |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 282 | nsecs = timekeeping_get_ns(); |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 283 | |
| 284 | } while (read_seqretry(&xtime_lock, seq)); |
| 285 | |
| 286 | set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec, |
| 287 | ts->tv_nsec + tomono.tv_nsec + nsecs); |
| 288 | } |
| 289 | EXPORT_SYMBOL_GPL(ktime_get_ts); |
| 290 | |
Alexander Gordeev | e2c18e4 | 2011-01-12 17:00:57 -0800 | [diff] [blame] | 291 | #ifdef CONFIG_NTP_PPS |
| 292 | |
| 293 | /** |
| 294 | * getnstime_raw_and_real - get day and raw monotonic time in timespec format |
| 295 | * @ts_raw: pointer to the timespec to be set to raw monotonic time |
| 296 | * @ts_real: pointer to the timespec to be set to the time of day |
| 297 | * |
| 298 | * This function reads both the time of day and raw monotonic time at the |
| 299 | * same time atomically and stores the resulting timestamps in timespec |
| 300 | * format. |
| 301 | */ |
| 302 | void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) |
| 303 | { |
| 304 | unsigned long seq; |
| 305 | s64 nsecs_raw, nsecs_real; |
| 306 | |
| 307 | WARN_ON_ONCE(timekeeping_suspended); |
| 308 | |
| 309 | do { |
| 310 | u32 arch_offset; |
| 311 | |
| 312 | seq = read_seqbegin(&xtime_lock); |
| 313 | |
| 314 | *ts_raw = raw_time; |
| 315 | *ts_real = xtime; |
| 316 | |
| 317 | nsecs_raw = timekeeping_get_ns_raw(); |
| 318 | nsecs_real = timekeeping_get_ns(); |
| 319 | |
| 320 | /* If arch requires, add in gettimeoffset() */ |
| 321 | arch_offset = arch_gettimeoffset(); |
| 322 | nsecs_raw += arch_offset; |
| 323 | nsecs_real += arch_offset; |
| 324 | |
| 325 | } while (read_seqretry(&xtime_lock, seq)); |
| 326 | |
| 327 | timespec_add_ns(ts_raw, nsecs_raw); |
| 328 | timespec_add_ns(ts_real, nsecs_real); |
| 329 | } |
| 330 | EXPORT_SYMBOL(getnstime_raw_and_real); |
| 331 | |
| 332 | #endif /* CONFIG_NTP_PPS */ |
| 333 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 334 | /** |
| 335 | * do_gettimeofday - Returns the time of day in a timeval |
| 336 | * @tv: pointer to the timeval to be set |
| 337 | * |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 338 | * NOTE: Users should be converted to using getnstimeofday() |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 339 | */ |
| 340 | void do_gettimeofday(struct timeval *tv) |
| 341 | { |
| 342 | struct timespec now; |
| 343 | |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 344 | getnstimeofday(&now); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 345 | tv->tv_sec = now.tv_sec; |
| 346 | tv->tv_usec = now.tv_nsec/1000; |
| 347 | } |
| 348 | |
| 349 | EXPORT_SYMBOL(do_gettimeofday); |
| 350 | /** |
| 351 | * do_settimeofday - Sets the time of day |
| 352 | * @tv: pointer to the timespec variable containing the new time |
| 353 | * |
| 354 | * Sets the time of day to the new time and update NTP and notify hrtimers |
| 355 | */ |
Richard Cochran | 1e6d767 | 2011-02-01 13:50:58 +0000 | [diff] [blame] | 356 | int do_settimeofday(const struct timespec *tv) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 357 | { |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 358 | struct timespec ts_delta; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 359 | unsigned long flags; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 360 | |
| 361 | if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) |
| 362 | return -EINVAL; |
| 363 | |
| 364 | write_seqlock_irqsave(&xtime_lock, flags); |
| 365 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 366 | timekeeping_forward_now(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 367 | |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 368 | ts_delta.tv_sec = tv->tv_sec - xtime.tv_sec; |
| 369 | ts_delta.tv_nsec = tv->tv_nsec - xtime.tv_nsec; |
| 370 | wall_to_monotonic = timespec_sub(wall_to_monotonic, ts_delta); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 371 | |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 372 | xtime = *tv; |
| 373 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 374 | timekeeper.ntp_error = 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 375 | ntp_clear(); |
| 376 | |
John Stultz | 7615856 | 2010-07-13 17:56:23 -0700 | [diff] [blame] | 377 | update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, |
| 378 | timekeeper.mult); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 379 | |
| 380 | write_sequnlock_irqrestore(&xtime_lock, flags); |
| 381 | |
| 382 | /* signal hrtimers about time change */ |
| 383 | clock_was_set(); |
| 384 | |
| 385 | return 0; |
| 386 | } |
| 387 | |
| 388 | EXPORT_SYMBOL(do_settimeofday); |
| 389 | |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 390 | |
| 391 | /** |
| 392 | * timekeeping_inject_offset - Adds or subtracts from the current time. |
| 393 | * @tv: pointer to the timespec variable containing the offset |
| 394 | * |
| 395 | * Adds or subtracts an offset value from the current time. |
| 396 | */ |
| 397 | int timekeeping_inject_offset(struct timespec *ts) |
| 398 | { |
| 399 | unsigned long flags; |
| 400 | |
| 401 | if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) |
| 402 | return -EINVAL; |
| 403 | |
| 404 | write_seqlock_irqsave(&xtime_lock, flags); |
| 405 | |
| 406 | timekeeping_forward_now(); |
| 407 | |
| 408 | xtime = timespec_add(xtime, *ts); |
| 409 | wall_to_monotonic = timespec_sub(wall_to_monotonic, *ts); |
| 410 | |
| 411 | timekeeper.ntp_error = 0; |
| 412 | ntp_clear(); |
| 413 | |
| 414 | update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, |
| 415 | timekeeper.mult); |
| 416 | |
| 417 | write_sequnlock_irqrestore(&xtime_lock, flags); |
| 418 | |
| 419 | /* signal hrtimers about time change */ |
| 420 | clock_was_set(); |
| 421 | |
| 422 | return 0; |
| 423 | } |
| 424 | EXPORT_SYMBOL(timekeeping_inject_offset); |
| 425 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 426 | /** |
| 427 | * change_clocksource - Swaps clocksources if a new one is available |
| 428 | * |
| 429 | * Accumulates current time interval and initializes new clocksource |
| 430 | */ |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 431 | static int change_clocksource(void *data) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 432 | { |
Magnus Damm | 4614e6a | 2009-04-21 12:24:02 -0700 | [diff] [blame] | 433 | struct clocksource *new, *old; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 434 | |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 435 | new = (struct clocksource *) data; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 436 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 437 | timekeeping_forward_now(); |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 438 | if (!new->enable || new->enable(new) == 0) { |
| 439 | old = timekeeper.clock; |
| 440 | timekeeper_setup_internals(new); |
| 441 | if (old->disable) |
| 442 | old->disable(old); |
| 443 | } |
| 444 | return 0; |
| 445 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 446 | |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 447 | /** |
| 448 | * timekeeping_notify - Install a new clock source |
| 449 | * @clock: pointer to the clock source |
| 450 | * |
| 451 | * This function is called from clocksource.c after a new, better clock |
| 452 | * source has been registered. The caller holds the clocksource_mutex. |
| 453 | */ |
| 454 | void timekeeping_notify(struct clocksource *clock) |
| 455 | { |
| 456 | if (timekeeper.clock == clock) |
Magnus Damm | 4614e6a | 2009-04-21 12:24:02 -0700 | [diff] [blame] | 457 | return; |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 458 | stop_machine(change_clocksource, clock, NULL); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 459 | tick_clock_notify(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 460 | } |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 461 | |
Thomas Gleixner | a40f262 | 2009-07-07 13:00:31 +0200 | [diff] [blame] | 462 | /** |
| 463 | * ktime_get_real - get the real (wall-) time in ktime_t format |
| 464 | * |
| 465 | * returns the time in ktime_t format |
| 466 | */ |
| 467 | ktime_t ktime_get_real(void) |
| 468 | { |
| 469 | struct timespec now; |
| 470 | |
| 471 | getnstimeofday(&now); |
| 472 | |
| 473 | return timespec_to_ktime(now); |
| 474 | } |
| 475 | EXPORT_SYMBOL_GPL(ktime_get_real); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 476 | |
| 477 | /** |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 478 | * getrawmonotonic - Returns the raw monotonic time in a timespec |
| 479 | * @ts: pointer to the timespec to be set |
| 480 | * |
| 481 | * Returns the raw monotonic time (completely un-modified by ntp) |
| 482 | */ |
| 483 | void getrawmonotonic(struct timespec *ts) |
| 484 | { |
| 485 | unsigned long seq; |
| 486 | s64 nsecs; |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 487 | |
| 488 | do { |
| 489 | seq = read_seqbegin(&xtime_lock); |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 490 | nsecs = timekeeping_get_ns_raw(); |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 491 | *ts = raw_time; |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 492 | |
| 493 | } while (read_seqretry(&xtime_lock, seq)); |
| 494 | |
| 495 | timespec_add_ns(ts, nsecs); |
| 496 | } |
| 497 | EXPORT_SYMBOL(getrawmonotonic); |
| 498 | |
| 499 | |
| 500 | /** |
Li Zefan | cf4fc6c | 2008-02-08 04:19:24 -0800 | [diff] [blame] | 501 | * timekeeping_valid_for_hres - Check if timekeeping is suitable for hres |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 502 | */ |
Li Zefan | cf4fc6c | 2008-02-08 04:19:24 -0800 | [diff] [blame] | 503 | int timekeeping_valid_for_hres(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 504 | { |
| 505 | unsigned long seq; |
| 506 | int ret; |
| 507 | |
| 508 | do { |
| 509 | seq = read_seqbegin(&xtime_lock); |
| 510 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 511 | ret = timekeeper.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 512 | |
| 513 | } while (read_seqretry(&xtime_lock, seq)); |
| 514 | |
| 515 | return ret; |
| 516 | } |
| 517 | |
| 518 | /** |
Jon Hunter | 9896246 | 2009-08-18 12:45:10 -0500 | [diff] [blame] | 519 | * timekeeping_max_deferment - Returns max time the clocksource can be deferred |
| 520 | * |
| 521 | * Caller must observe xtime_lock via read_seqbegin/read_seqretry to |
| 522 | * ensure that the clocksource does not change! |
| 523 | */ |
| 524 | u64 timekeeping_max_deferment(void) |
| 525 | { |
| 526 | return timekeeper.clock->max_idle_ns; |
| 527 | } |
| 528 | |
| 529 | /** |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 530 | * read_persistent_clock - Return time from the persistent clock. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 531 | * |
| 532 | * Weak dummy function for arches that do not yet support it. |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 533 | * Reads the time from the battery backed persistent clock. |
| 534 | * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 535 | * |
| 536 | * XXX - Do be sure to remove it once all arches implement it. |
| 537 | */ |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 538 | void __attribute__((weak)) read_persistent_clock(struct timespec *ts) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 539 | { |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 540 | ts->tv_sec = 0; |
| 541 | ts->tv_nsec = 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 542 | } |
| 543 | |
Martin Schwidefsky | 23970e3 | 2009-08-14 15:47:32 +0200 | [diff] [blame] | 544 | /** |
| 545 | * read_boot_clock - Return time of the system start. |
| 546 | * |
| 547 | * Weak dummy function for arches that do not yet support it. |
| 548 | * Function to read the exact time the system has been started. |
| 549 | * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported. |
| 550 | * |
| 551 | * XXX - Do be sure to remove it once all arches implement it. |
| 552 | */ |
| 553 | void __attribute__((weak)) read_boot_clock(struct timespec *ts) |
| 554 | { |
| 555 | ts->tv_sec = 0; |
| 556 | ts->tv_nsec = 0; |
| 557 | } |
| 558 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 559 | /* |
| 560 | * timekeeping_init - Initializes the clocksource and common timekeeping values |
| 561 | */ |
| 562 | void __init timekeeping_init(void) |
| 563 | { |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 564 | struct clocksource *clock; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 565 | unsigned long flags; |
Martin Schwidefsky | 23970e3 | 2009-08-14 15:47:32 +0200 | [diff] [blame] | 566 | struct timespec now, boot; |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 567 | |
| 568 | read_persistent_clock(&now); |
Martin Schwidefsky | 23970e3 | 2009-08-14 15:47:32 +0200 | [diff] [blame] | 569 | read_boot_clock(&boot); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 570 | |
| 571 | write_seqlock_irqsave(&xtime_lock, flags); |
| 572 | |
Roman Zippel | 7dffa3c | 2008-05-01 04:34:41 -0700 | [diff] [blame] | 573 | ntp_init(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 574 | |
Martin Schwidefsky | f1b8274 | 2009-08-14 15:47:21 +0200 | [diff] [blame] | 575 | clock = clocksource_default_clock(); |
Martin Schwidefsky | a0f7d48 | 2009-08-14 15:47:19 +0200 | [diff] [blame] | 576 | if (clock->enable) |
| 577 | clock->enable(clock); |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 578 | timekeeper_setup_internals(clock); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 579 | |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 580 | xtime.tv_sec = now.tv_sec; |
| 581 | xtime.tv_nsec = now.tv_nsec; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 582 | raw_time.tv_sec = 0; |
| 583 | raw_time.tv_nsec = 0; |
Martin Schwidefsky | 23970e3 | 2009-08-14 15:47:32 +0200 | [diff] [blame] | 584 | if (boot.tv_sec == 0 && boot.tv_nsec == 0) { |
| 585 | boot.tv_sec = xtime.tv_sec; |
| 586 | boot.tv_nsec = xtime.tv_nsec; |
| 587 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 588 | set_normalized_timespec(&wall_to_monotonic, |
Martin Schwidefsky | 23970e3 | 2009-08-14 15:47:32 +0200 | [diff] [blame] | 589 | -boot.tv_sec, -boot.tv_nsec); |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 590 | total_sleep_time.tv_sec = 0; |
| 591 | total_sleep_time.tv_nsec = 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 592 | write_sequnlock_irqrestore(&xtime_lock, flags); |
| 593 | } |
| 594 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 595 | /* time in seconds when suspend began */ |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 596 | static struct timespec timekeeping_suspend_time; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 597 | |
| 598 | /** |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 599 | * __timekeeping_inject_sleeptime - Internal function to add sleep interval |
| 600 | * @delta: pointer to a timespec delta value |
| 601 | * |
| 602 | * Takes a timespec offset measuring a suspend interval and properly |
| 603 | * adds the sleep offset to the timekeeping variables. |
| 604 | */ |
| 605 | static void __timekeeping_inject_sleeptime(struct timespec *delta) |
| 606 | { |
John Stultz | cb5de2f8d | 2011-06-01 18:18:09 -0700 | [diff] [blame] | 607 | if (!timespec_valid(delta)) { |
John Stultz | cbaa515 | 2011-07-20 15:42:55 -0700 | [diff] [blame] | 608 | printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid " |
John Stultz | cb5de2f8d | 2011-06-01 18:18:09 -0700 | [diff] [blame] | 609 | "sleep delta value!\n"); |
| 610 | return; |
| 611 | } |
| 612 | |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 613 | xtime = timespec_add(xtime, *delta); |
| 614 | wall_to_monotonic = timespec_sub(wall_to_monotonic, *delta); |
| 615 | total_sleep_time = timespec_add(total_sleep_time, *delta); |
| 616 | } |
| 617 | |
| 618 | |
| 619 | /** |
| 620 | * timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values |
| 621 | * @delta: pointer to a timespec delta value |
| 622 | * |
| 623 | * This hook is for architectures that cannot support read_persistent_clock |
| 624 | * because their RTC/persistent clock is only accessible when irqs are enabled. |
| 625 | * |
| 626 | * This function should only be called by rtc_resume(), and allows |
| 627 | * a suspend offset to be injected into the timekeeping values. |
| 628 | */ |
| 629 | void timekeeping_inject_sleeptime(struct timespec *delta) |
| 630 | { |
| 631 | unsigned long flags; |
| 632 | struct timespec ts; |
| 633 | |
| 634 | /* Make sure we don't set the clock twice */ |
| 635 | read_persistent_clock(&ts); |
| 636 | if (!(ts.tv_sec == 0 && ts.tv_nsec == 0)) |
| 637 | return; |
| 638 | |
| 639 | write_seqlock_irqsave(&xtime_lock, flags); |
| 640 | timekeeping_forward_now(); |
| 641 | |
| 642 | __timekeeping_inject_sleeptime(delta); |
| 643 | |
| 644 | timekeeper.ntp_error = 0; |
| 645 | ntp_clear(); |
| 646 | update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, |
| 647 | timekeeper.mult); |
| 648 | |
| 649 | write_sequnlock_irqrestore(&xtime_lock, flags); |
| 650 | |
| 651 | /* signal hrtimers about time change */ |
| 652 | clock_was_set(); |
| 653 | } |
| 654 | |
| 655 | |
| 656 | /** |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 657 | * timekeeping_resume - Resumes the generic timekeeping subsystem. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 658 | * |
| 659 | * This is for the generic clocksource timekeeping. |
| 660 | * xtime/wall_to_monotonic/jiffies/etc are |
| 661 | * still managed by arch specific suspend/resume code. |
| 662 | */ |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 663 | static void timekeeping_resume(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 664 | { |
| 665 | unsigned long flags; |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 666 | struct timespec ts; |
| 667 | |
| 668 | read_persistent_clock(&ts); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 669 | |
Thomas Gleixner | d10ff3f | 2007-05-14 11:10:02 +0200 | [diff] [blame] | 670 | clocksource_resume(); |
| 671 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 672 | write_seqlock_irqsave(&xtime_lock, flags); |
| 673 | |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 674 | if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) { |
| 675 | ts = timespec_sub(ts, timekeeping_suspend_time); |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 676 | __timekeeping_inject_sleeptime(&ts); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 677 | } |
| 678 | /* re-base the last cycle value */ |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 679 | timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock); |
| 680 | timekeeper.ntp_error = 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 681 | timekeeping_suspended = 0; |
| 682 | write_sequnlock_irqrestore(&xtime_lock, flags); |
| 683 | |
| 684 | touch_softlockup_watchdog(); |
| 685 | |
| 686 | clockevents_notify(CLOCK_EVT_NOTIFY_RESUME, NULL); |
| 687 | |
| 688 | /* Resume hrtimers */ |
Thomas Gleixner | b12a03c | 2011-05-02 16:48:57 +0200 | [diff] [blame] | 689 | hrtimers_resume(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 690 | } |
| 691 | |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 692 | static int timekeeping_suspend(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 693 | { |
| 694 | unsigned long flags; |
John Stultz | cb33217 | 2011-05-31 22:53:23 -0700 | [diff] [blame] | 695 | struct timespec delta, delta_delta; |
| 696 | static struct timespec old_delta; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 697 | |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 698 | read_persistent_clock(&timekeeping_suspend_time); |
Thomas Gleixner | 3be9095 | 2007-09-16 15:36:43 +0200 | [diff] [blame] | 699 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 700 | write_seqlock_irqsave(&xtime_lock, flags); |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 701 | timekeeping_forward_now(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 702 | timekeeping_suspended = 1; |
John Stultz | cb33217 | 2011-05-31 22:53:23 -0700 | [diff] [blame] | 703 | |
| 704 | /* |
| 705 | * To avoid drift caused by repeated suspend/resumes, |
| 706 | * which each can add ~1 second drift error, |
| 707 | * try to compensate so the difference in system time |
| 708 | * and persistent_clock time stays close to constant. |
| 709 | */ |
| 710 | delta = timespec_sub(xtime, timekeeping_suspend_time); |
| 711 | delta_delta = timespec_sub(delta, old_delta); |
| 712 | if (abs(delta_delta.tv_sec) >= 2) { |
| 713 | /* |
| 714 | * if delta_delta is too large, assume time correction |
| 715 | * has occured and set old_delta to the current delta. |
| 716 | */ |
| 717 | old_delta = delta; |
| 718 | } else { |
| 719 | /* Otherwise try to adjust old_system to compensate */ |
| 720 | timekeeping_suspend_time = |
| 721 | timespec_add(timekeeping_suspend_time, delta_delta); |
| 722 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 723 | write_sequnlock_irqrestore(&xtime_lock, flags); |
| 724 | |
| 725 | clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL); |
Magnus Damm | c54a42b | 2010-02-02 14:41:41 -0800 | [diff] [blame] | 726 | clocksource_suspend(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 727 | |
| 728 | return 0; |
| 729 | } |
| 730 | |
| 731 | /* sysfs resume/suspend bits for timekeeping */ |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 732 | static struct syscore_ops timekeeping_syscore_ops = { |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 733 | .resume = timekeeping_resume, |
| 734 | .suspend = timekeeping_suspend, |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 735 | }; |
| 736 | |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 737 | static int __init timekeeping_init_ops(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 738 | { |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 739 | register_syscore_ops(&timekeeping_syscore_ops); |
| 740 | return 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 741 | } |
| 742 | |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 743 | device_initcall(timekeeping_init_ops); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 744 | |
| 745 | /* |
| 746 | * If the error is already larger, we look ahead even further |
| 747 | * to compensate for late or lost adjustments. |
| 748 | */ |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 749 | static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval, |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 750 | s64 *offset) |
| 751 | { |
| 752 | s64 tick_error, i; |
| 753 | u32 look_ahead, adj; |
| 754 | s32 error2, mult; |
| 755 | |
| 756 | /* |
| 757 | * Use the current error value to determine how much to look ahead. |
| 758 | * The larger the error the slower we adjust for it to avoid problems |
| 759 | * with losing too many ticks, otherwise we would overadjust and |
| 760 | * produce an even larger error. The smaller the adjustment the |
| 761 | * faster we try to adjust for it, as lost ticks can do less harm |
Li Zefan | 3eb0567 | 2008-02-08 04:19:25 -0800 | [diff] [blame] | 762 | * here. This is tuned so that an error of about 1 msec is adjusted |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 763 | * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks). |
| 764 | */ |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 765 | error2 = timekeeper.ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 766 | error2 = abs(error2); |
| 767 | for (look_ahead = 0; error2 > 0; look_ahead++) |
| 768 | error2 >>= 2; |
| 769 | |
| 770 | /* |
| 771 | * Now calculate the error in (1 << look_ahead) ticks, but first |
| 772 | * remove the single look ahead already included in the error. |
| 773 | */ |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 774 | tick_error = tick_length >> (timekeeper.ntp_error_shift + 1); |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 775 | tick_error -= timekeeper.xtime_interval >> 1; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 776 | error = ((error - tick_error) >> look_ahead) + tick_error; |
| 777 | |
| 778 | /* Finally calculate the adjustment shift value. */ |
| 779 | i = *interval; |
| 780 | mult = 1; |
| 781 | if (error < 0) { |
| 782 | error = -error; |
| 783 | *interval = -*interval; |
| 784 | *offset = -*offset; |
| 785 | mult = -1; |
| 786 | } |
| 787 | for (adj = 0; error > i; adj++) |
| 788 | error >>= 1; |
| 789 | |
| 790 | *interval <<= adj; |
| 791 | *offset <<= adj; |
| 792 | return mult << adj; |
| 793 | } |
| 794 | |
| 795 | /* |
| 796 | * Adjust the multiplier to reduce the error value, |
| 797 | * this is optimized for the most common adjustments of -1,0,1, |
| 798 | * for other values we can do a bit more work. |
| 799 | */ |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 800 | static void timekeeping_adjust(s64 offset) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 801 | { |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 802 | s64 error, interval = timekeeper.cycle_interval; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 803 | int adj; |
| 804 | |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 805 | error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 806 | if (error > interval) { |
| 807 | error >>= 2; |
| 808 | if (likely(error <= interval)) |
| 809 | adj = 1; |
| 810 | else |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 811 | adj = timekeeping_bigadjust(error, &interval, &offset); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 812 | } else if (error < -interval) { |
| 813 | error >>= 2; |
| 814 | if (likely(error >= -interval)) { |
| 815 | adj = -1; |
| 816 | interval = -interval; |
| 817 | offset = -offset; |
| 818 | } else |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 819 | adj = timekeeping_bigadjust(error, &interval, &offset); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 820 | } else |
| 821 | return; |
| 822 | |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 823 | timekeeper.mult += adj; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 824 | timekeeper.xtime_interval += interval; |
| 825 | timekeeper.xtime_nsec -= offset; |
| 826 | timekeeper.ntp_error -= (interval - offset) << |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 827 | timekeeper.ntp_error_shift; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 828 | } |
| 829 | |
Linus Torvalds | 83f57a1 | 2009-12-22 14:10:37 -0800 | [diff] [blame] | 830 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 831 | /** |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 832 | * logarithmic_accumulation - shifted accumulation of cycles |
| 833 | * |
| 834 | * This functions accumulates a shifted interval of cycles into |
| 835 | * into a shifted interval nanoseconds. Allows for O(log) accumulation |
| 836 | * loop. |
| 837 | * |
| 838 | * Returns the unconsumed cycles. |
| 839 | */ |
| 840 | static cycle_t logarithmic_accumulation(cycle_t offset, int shift) |
| 841 | { |
| 842 | u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift; |
Jason Wessel | deda2e8 | 2010-08-09 14:20:09 -0700 | [diff] [blame] | 843 | u64 raw_nsecs; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 844 | |
| 845 | /* If the offset is smaller then a shifted interval, do nothing */ |
| 846 | if (offset < timekeeper.cycle_interval<<shift) |
| 847 | return offset; |
| 848 | |
| 849 | /* Accumulate one shifted interval */ |
| 850 | offset -= timekeeper.cycle_interval << shift; |
| 851 | timekeeper.clock->cycle_last += timekeeper.cycle_interval << shift; |
| 852 | |
| 853 | timekeeper.xtime_nsec += timekeeper.xtime_interval << shift; |
| 854 | while (timekeeper.xtime_nsec >= nsecps) { |
| 855 | timekeeper.xtime_nsec -= nsecps; |
| 856 | xtime.tv_sec++; |
| 857 | second_overflow(); |
| 858 | } |
| 859 | |
Jason Wessel | deda2e8 | 2010-08-09 14:20:09 -0700 | [diff] [blame] | 860 | /* Accumulate raw time */ |
| 861 | raw_nsecs = timekeeper.raw_interval << shift; |
| 862 | raw_nsecs += raw_time.tv_nsec; |
John Stultz | c7dcf87 | 2010-08-13 11:30:58 -0700 | [diff] [blame] | 863 | if (raw_nsecs >= NSEC_PER_SEC) { |
| 864 | u64 raw_secs = raw_nsecs; |
| 865 | raw_nsecs = do_div(raw_secs, NSEC_PER_SEC); |
| 866 | raw_time.tv_sec += raw_secs; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 867 | } |
Jason Wessel | deda2e8 | 2010-08-09 14:20:09 -0700 | [diff] [blame] | 868 | raw_time.tv_nsec = raw_nsecs; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 869 | |
| 870 | /* Accumulate error between NTP and clock interval */ |
| 871 | timekeeper.ntp_error += tick_length << shift; |
Kasper Pedersen | a386b5a | 2010-10-20 15:55:15 -0700 | [diff] [blame] | 872 | timekeeper.ntp_error -= |
| 873 | (timekeeper.xtime_interval + timekeeper.xtime_remainder) << |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 874 | (timekeeper.ntp_error_shift + shift); |
| 875 | |
| 876 | return offset; |
| 877 | } |
| 878 | |
Linus Torvalds | 83f57a1 | 2009-12-22 14:10:37 -0800 | [diff] [blame] | 879 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 880 | /** |
| 881 | * update_wall_time - Uses the current clocksource to increment the wall time |
| 882 | * |
| 883 | * Called from the timer interrupt, must hold a write on xtime_lock. |
| 884 | */ |
Torben Hohn | 871cf1e | 2011-01-27 15:58:55 +0100 | [diff] [blame] | 885 | static void update_wall_time(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 886 | { |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 887 | struct clocksource *clock; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 888 | cycle_t offset; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 889 | int shift = 0, maxshift; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 890 | |
| 891 | /* Make sure we're fully resumed: */ |
| 892 | if (unlikely(timekeeping_suspended)) |
| 893 | return; |
| 894 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 895 | clock = timekeeper.clock; |
John Stultz | 592913e | 2010-07-13 17:56:20 -0700 | [diff] [blame] | 896 | |
| 897 | #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 898 | offset = timekeeper.cycle_interval; |
John Stultz | 592913e | 2010-07-13 17:56:20 -0700 | [diff] [blame] | 899 | #else |
| 900 | offset = (clock->read(clock) - clock->cycle_last) & clock->mask; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 901 | #endif |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 902 | timekeeper.xtime_nsec = (s64)xtime.tv_nsec << timekeeper.shift; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 903 | |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 904 | /* |
| 905 | * With NO_HZ we may have to accumulate many cycle_intervals |
| 906 | * (think "ticks") worth of time at once. To do this efficiently, |
| 907 | * we calculate the largest doubling multiple of cycle_intervals |
| 908 | * that is smaller then the offset. We then accumulate that |
| 909 | * chunk in one go, and then try to consume the next smaller |
| 910 | * doubled multiple. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 911 | */ |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 912 | shift = ilog2(offset) - ilog2(timekeeper.cycle_interval); |
| 913 | shift = max(0, shift); |
| 914 | /* Bound shift to one less then what overflows tick_length */ |
| 915 | maxshift = (8*sizeof(tick_length) - (ilog2(tick_length)+1)) - 1; |
| 916 | shift = min(shift, maxshift); |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 917 | while (offset >= timekeeper.cycle_interval) { |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 918 | offset = logarithmic_accumulation(offset, shift); |
John Stultz | 830ec04 | 2010-03-18 14:47:30 -0700 | [diff] [blame] | 919 | if(offset < timekeeper.cycle_interval<<shift) |
| 920 | shift--; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 921 | } |
| 922 | |
| 923 | /* correct the clock when NTP error is too big */ |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 924 | timekeeping_adjust(offset); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 925 | |
john stultz | 6c9bacb | 2008-12-01 18:34:41 -0800 | [diff] [blame] | 926 | /* |
| 927 | * Since in the loop above, we accumulate any amount of time |
| 928 | * in xtime_nsec over a second into xtime.tv_sec, its possible for |
| 929 | * xtime_nsec to be fairly small after the loop. Further, if we're |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 930 | * slightly speeding the clocksource up in timekeeping_adjust(), |
john stultz | 6c9bacb | 2008-12-01 18:34:41 -0800 | [diff] [blame] | 931 | * its possible the required corrective factor to xtime_nsec could |
| 932 | * cause it to underflow. |
| 933 | * |
| 934 | * Now, we cannot simply roll the accumulated second back, since |
| 935 | * the NTP subsystem has been notified via second_overflow. So |
| 936 | * instead we push xtime_nsec forward by the amount we underflowed, |
| 937 | * and add that amount into the error. |
| 938 | * |
| 939 | * We'll correct this error next time through this function, when |
| 940 | * xtime_nsec is not as small. |
| 941 | */ |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 942 | if (unlikely((s64)timekeeper.xtime_nsec < 0)) { |
| 943 | s64 neg = -(s64)timekeeper.xtime_nsec; |
| 944 | timekeeper.xtime_nsec = 0; |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 945 | timekeeper.ntp_error += neg << timekeeper.ntp_error_shift; |
john stultz | 6c9bacb | 2008-12-01 18:34:41 -0800 | [diff] [blame] | 946 | } |
| 947 | |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 948 | |
| 949 | /* |
| 950 | * Store full nanoseconds into xtime after rounding it up and |
Roman Zippel | 5cd1c9c | 2008-09-22 14:42:43 -0700 | [diff] [blame] | 951 | * add the remainder to the error difference. |
| 952 | */ |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 953 | xtime.tv_nsec = ((s64) timekeeper.xtime_nsec >> timekeeper.shift) + 1; |
| 954 | timekeeper.xtime_nsec -= (s64) xtime.tv_nsec << timekeeper.shift; |
| 955 | timekeeper.ntp_error += timekeeper.xtime_nsec << |
| 956 | timekeeper.ntp_error_shift; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 957 | |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 958 | /* |
| 959 | * Finally, make sure that after the rounding |
| 960 | * xtime.tv_nsec isn't larger then NSEC_PER_SEC |
| 961 | */ |
| 962 | if (unlikely(xtime.tv_nsec >= NSEC_PER_SEC)) { |
| 963 | xtime.tv_nsec -= NSEC_PER_SEC; |
| 964 | xtime.tv_sec++; |
| 965 | second_overflow(); |
| 966 | } |
Linus Torvalds | 83f57a1 | 2009-12-22 14:10:37 -0800 | [diff] [blame] | 967 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 968 | /* check to see if there is a new clocksource to use */ |
John Stultz | 7615856 | 2010-07-13 17:56:23 -0700 | [diff] [blame] | 969 | update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, |
| 970 | timekeeper.mult); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 971 | } |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 972 | |
| 973 | /** |
| 974 | * getboottime - Return the real time of system boot. |
| 975 | * @ts: pointer to the timespec to be set |
| 976 | * |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 977 | * Returns the wall-time of boot in a timespec. |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 978 | * |
| 979 | * This is based on the wall_to_monotonic offset and the total suspend |
| 980 | * time. Calls to settimeofday will affect the value returned (which |
| 981 | * basically means that however wrong your real time clock is at boot time, |
| 982 | * you get the right time here). |
| 983 | */ |
| 984 | void getboottime(struct timespec *ts) |
| 985 | { |
Hiroshi Shimamoto | 36d4748 | 2009-08-25 15:08:30 +0900 | [diff] [blame] | 986 | struct timespec boottime = { |
| 987 | .tv_sec = wall_to_monotonic.tv_sec + total_sleep_time.tv_sec, |
| 988 | .tv_nsec = wall_to_monotonic.tv_nsec + total_sleep_time.tv_nsec |
| 989 | }; |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 990 | |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 991 | set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec); |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 992 | } |
Jason Wang | c93d89f | 2010-01-27 19:13:40 +0800 | [diff] [blame] | 993 | EXPORT_SYMBOL_GPL(getboottime); |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 994 | |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 995 | |
| 996 | /** |
| 997 | * get_monotonic_boottime - Returns monotonic time since boot |
| 998 | * @ts: pointer to the timespec to be set |
| 999 | * |
| 1000 | * Returns the monotonic time since boot in a timespec. |
| 1001 | * |
| 1002 | * This is similar to CLOCK_MONTONIC/ktime_get_ts, but also |
| 1003 | * includes the time spent in suspend. |
| 1004 | */ |
| 1005 | void get_monotonic_boottime(struct timespec *ts) |
| 1006 | { |
| 1007 | struct timespec tomono, sleep; |
| 1008 | unsigned int seq; |
| 1009 | s64 nsecs; |
| 1010 | |
| 1011 | WARN_ON(timekeeping_suspended); |
| 1012 | |
| 1013 | do { |
| 1014 | seq = read_seqbegin(&xtime_lock); |
| 1015 | *ts = xtime; |
| 1016 | tomono = wall_to_monotonic; |
| 1017 | sleep = total_sleep_time; |
| 1018 | nsecs = timekeeping_get_ns(); |
| 1019 | |
| 1020 | } while (read_seqretry(&xtime_lock, seq)); |
| 1021 | |
| 1022 | set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec + sleep.tv_sec, |
| 1023 | ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec + nsecs); |
| 1024 | } |
| 1025 | EXPORT_SYMBOL_GPL(get_monotonic_boottime); |
| 1026 | |
| 1027 | /** |
| 1028 | * ktime_get_boottime - Returns monotonic time since boot in a ktime |
| 1029 | * |
| 1030 | * Returns the monotonic time since boot in a ktime |
| 1031 | * |
| 1032 | * This is similar to CLOCK_MONTONIC/ktime_get, but also |
| 1033 | * includes the time spent in suspend. |
| 1034 | */ |
| 1035 | ktime_t ktime_get_boottime(void) |
| 1036 | { |
| 1037 | struct timespec ts; |
| 1038 | |
| 1039 | get_monotonic_boottime(&ts); |
| 1040 | return timespec_to_ktime(ts); |
| 1041 | } |
| 1042 | EXPORT_SYMBOL_GPL(ktime_get_boottime); |
| 1043 | |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 1044 | /** |
| 1045 | * monotonic_to_bootbased - Convert the monotonic time to boot based. |
| 1046 | * @ts: pointer to the timespec to be converted |
| 1047 | */ |
| 1048 | void monotonic_to_bootbased(struct timespec *ts) |
| 1049 | { |
John Stultz | ce3bf7a | 2010-07-13 17:56:19 -0700 | [diff] [blame] | 1050 | *ts = timespec_add(*ts, total_sleep_time); |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 1051 | } |
Jason Wang | c93d89f | 2010-01-27 19:13:40 +0800 | [diff] [blame] | 1052 | EXPORT_SYMBOL_GPL(monotonic_to_bootbased); |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1053 | |
john stultz | 17c38b7 | 2007-07-24 18:38:34 -0700 | [diff] [blame] | 1054 | unsigned long get_seconds(void) |
| 1055 | { |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 1056 | return xtime.tv_sec; |
john stultz | 17c38b7 | 2007-07-24 18:38:34 -0700 | [diff] [blame] | 1057 | } |
| 1058 | EXPORT_SYMBOL(get_seconds); |
| 1059 | |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1060 | struct timespec __current_kernel_time(void) |
| 1061 | { |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 1062 | return xtime; |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1063 | } |
john stultz | 17c38b7 | 2007-07-24 18:38:34 -0700 | [diff] [blame] | 1064 | |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1065 | struct timespec current_kernel_time(void) |
| 1066 | { |
| 1067 | struct timespec now; |
| 1068 | unsigned long seq; |
| 1069 | |
| 1070 | do { |
| 1071 | seq = read_seqbegin(&xtime_lock); |
Linus Torvalds | 83f57a1 | 2009-12-22 14:10:37 -0800 | [diff] [blame] | 1072 | |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 1073 | now = xtime; |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1074 | } while (read_seqretry(&xtime_lock, seq)); |
| 1075 | |
| 1076 | return now; |
| 1077 | } |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1078 | EXPORT_SYMBOL(current_kernel_time); |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1079 | |
| 1080 | struct timespec get_monotonic_coarse(void) |
| 1081 | { |
| 1082 | struct timespec now, mono; |
| 1083 | unsigned long seq; |
| 1084 | |
| 1085 | do { |
| 1086 | seq = read_seqbegin(&xtime_lock); |
Linus Torvalds | 83f57a1 | 2009-12-22 14:10:37 -0800 | [diff] [blame] | 1087 | |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 1088 | now = xtime; |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1089 | mono = wall_to_monotonic; |
| 1090 | } while (read_seqretry(&xtime_lock, seq)); |
| 1091 | |
| 1092 | set_normalized_timespec(&now, now.tv_sec + mono.tv_sec, |
| 1093 | now.tv_nsec + mono.tv_nsec); |
| 1094 | return now; |
| 1095 | } |
Torben Hohn | 871cf1e | 2011-01-27 15:58:55 +0100 | [diff] [blame] | 1096 | |
| 1097 | /* |
| 1098 | * The 64-bit jiffies value is not atomic - you MUST NOT read it |
| 1099 | * without sampling the sequence number in xtime_lock. |
| 1100 | * jiffies is defined in the linker script... |
| 1101 | */ |
| 1102 | void do_timer(unsigned long ticks) |
| 1103 | { |
| 1104 | jiffies_64 += ticks; |
| 1105 | update_wall_time(); |
| 1106 | calc_global_load(ticks); |
| 1107 | } |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1108 | |
| 1109 | /** |
John Stultz | 314ac37 | 2011-02-14 18:43:08 -0800 | [diff] [blame] | 1110 | * get_xtime_and_monotonic_and_sleep_offset() - get xtime, wall_to_monotonic, |
| 1111 | * and sleep offsets. |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1112 | * @xtim: pointer to timespec to be set with xtime |
| 1113 | * @wtom: pointer to timespec to be set with wall_to_monotonic |
John Stultz | 314ac37 | 2011-02-14 18:43:08 -0800 | [diff] [blame] | 1114 | * @sleep: pointer to timespec to be set with time in suspend |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1115 | */ |
John Stultz | 314ac37 | 2011-02-14 18:43:08 -0800 | [diff] [blame] | 1116 | void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim, |
| 1117 | struct timespec *wtom, struct timespec *sleep) |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1118 | { |
| 1119 | unsigned long seq; |
| 1120 | |
| 1121 | do { |
| 1122 | seq = read_seqbegin(&xtime_lock); |
| 1123 | *xtim = xtime; |
| 1124 | *wtom = wall_to_monotonic; |
John Stultz | 314ac37 | 2011-02-14 18:43:08 -0800 | [diff] [blame] | 1125 | *sleep = total_sleep_time; |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1126 | } while (read_seqretry(&xtime_lock, seq)); |
| 1127 | } |
Torben Hohn | f0af911a9 | 2011-01-27 15:59:10 +0100 | [diff] [blame] | 1128 | |
| 1129 | /** |
Thomas Gleixner | 99ee531 | 2011-04-27 14:16:42 +0200 | [diff] [blame] | 1130 | * ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format |
| 1131 | */ |
| 1132 | ktime_t ktime_get_monotonic_offset(void) |
| 1133 | { |
| 1134 | unsigned long seq; |
| 1135 | struct timespec wtom; |
| 1136 | |
| 1137 | do { |
| 1138 | seq = read_seqbegin(&xtime_lock); |
| 1139 | wtom = wall_to_monotonic; |
| 1140 | } while (read_seqretry(&xtime_lock, seq)); |
| 1141 | return timespec_to_ktime(wtom); |
| 1142 | } |
| 1143 | |
| 1144 | /** |
Torben Hohn | f0af911a9 | 2011-01-27 15:59:10 +0100 | [diff] [blame] | 1145 | * xtime_update() - advances the timekeeping infrastructure |
| 1146 | * @ticks: number of ticks, that have elapsed since the last call. |
| 1147 | * |
| 1148 | * Must be called with interrupts disabled. |
| 1149 | */ |
| 1150 | void xtime_update(unsigned long ticks) |
| 1151 | { |
| 1152 | write_seqlock(&xtime_lock); |
| 1153 | do_timer(ticks); |
| 1154 | write_sequnlock(&xtime_lock); |
| 1155 | } |