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. */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 27 | struct clocksource *clock; |
Thomas Gleixner | 058892e | 2011-11-13 23:19:48 +0000 | [diff] [blame] | 28 | /* NTP adjusted clock multiplier */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 29 | u32 mult; |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 30 | /* The shift value of the current clocksource. */ |
John Stultz | fee84c4 | 2012-07-13 01:21:52 -0400 | [diff] [blame] | 31 | u32 shift; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 32 | /* Number of clock cycles in one NTP interval. */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 33 | cycle_t cycle_interval; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 34 | /* Number of clock shifted nano seconds in one NTP interval. */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 35 | u64 xtime_interval; |
Kasper Pedersen | a386b5a | 2010-10-20 15:55:15 -0700 | [diff] [blame] | 36 | /* shifted nano seconds left over when rounding cycle_interval */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 37 | s64 xtime_remainder; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 38 | /* Raw nano seconds accumulated per NTP interval. */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 39 | u32 raw_interval; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 40 | |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 41 | /* Current CLOCK_REALTIME time in seconds */ |
| 42 | u64 xtime_sec; |
| 43 | /* Clock shifted nano seconds */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 44 | u64 xtime_nsec; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 45 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 46 | /* Difference between accumulated time and NTP time in ntp |
| 47 | * shifted nano seconds. */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 48 | s64 ntp_error; |
Martin Schwidefsky | 23ce721 | 2009-08-14 15:47:27 +0200 | [diff] [blame] | 49 | /* Shift conversion between clock shifted nano seconds and |
| 50 | * ntp shifted nano seconds. */ |
John Stultz | fee84c4 | 2012-07-13 01:21:52 -0400 | [diff] [blame] | 51 | u32 ntp_error_shift; |
John Stultz | 00c5fb7 | 2011-11-14 11:23:15 -0800 | [diff] [blame] | 52 | |
John Stultz | d9f7217 | 2011-11-14 11:29:32 -0800 | [diff] [blame] | 53 | /* |
| 54 | * wall_to_monotonic is what we need to add to xtime (or xtime corrected |
| 55 | * for sub jiffie times) to get to monotonic time. Monotonic is pegged |
| 56 | * at zero at system boot time, so wall_to_monotonic will be negative, |
| 57 | * however, we will ALWAYS keep the tv_nsec part positive so we can use |
| 58 | * the usual normalization. |
| 59 | * |
| 60 | * wall_to_monotonic is moved after resume from suspend for the |
| 61 | * monotonic time not to jump. We need to add total_sleep_time to |
| 62 | * wall_to_monotonic to get the real boot based time offset. |
| 63 | * |
| 64 | * - wall_to_monotonic is no longer the boot time, getboottime must be |
| 65 | * used instead. |
| 66 | */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 67 | struct timespec wall_to_monotonic; |
Thomas Gleixner | 5b9fe75 | 2012-07-10 18:43:21 -0400 | [diff] [blame] | 68 | /* Offset clock monotonic -> clock realtime */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 69 | ktime_t offs_real; |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 70 | /* time spent in suspend */ |
| 71 | struct timespec total_sleep_time; |
Thomas Gleixner | 5b9fe75 | 2012-07-10 18:43:21 -0400 | [diff] [blame] | 72 | /* Offset clock monotonic -> clock boottime */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 73 | ktime_t offs_boot; |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 74 | /* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */ |
| 75 | struct timespec raw_time; |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 76 | /* Seqlock for all timekeeper values */ |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 77 | seqlock_t lock; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 78 | }; |
| 79 | |
H Hartley Sweeten | afa14e7 | 2011-01-11 17:59:38 -0600 | [diff] [blame] | 80 | static struct timekeeper timekeeper; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 81 | |
John Stultz | 8fcce54 | 2011-11-14 11:46:39 -0800 | [diff] [blame] | 82 | /* |
| 83 | * This read-write spinlock protects us from races in SMP while |
| 84 | * playing with xtime. |
| 85 | */ |
| 86 | __cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock); |
| 87 | |
John Stultz | 8fcce54 | 2011-11-14 11:46:39 -0800 | [diff] [blame] | 88 | /* flag for if timekeeping is suspended */ |
| 89 | int __read_mostly timekeeping_suspended; |
| 90 | |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 91 | static inline void tk_normalize_xtime(struct timekeeper *tk) |
| 92 | { |
| 93 | while (tk->xtime_nsec >= ((u64)NSEC_PER_SEC << tk->shift)) { |
| 94 | tk->xtime_nsec -= (u64)NSEC_PER_SEC << tk->shift; |
| 95 | tk->xtime_sec++; |
| 96 | } |
| 97 | } |
John Stultz | 8fcce54 | 2011-11-14 11:46:39 -0800 | [diff] [blame] | 98 | |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 99 | static struct timespec tk_xtime(struct timekeeper *tk) |
| 100 | { |
| 101 | struct timespec ts; |
| 102 | |
| 103 | ts.tv_sec = tk->xtime_sec; |
| 104 | ts.tv_nsec = (long)(tk->xtime_nsec >> tk->shift); |
| 105 | return ts; |
| 106 | } |
| 107 | |
| 108 | static void tk_set_xtime(struct timekeeper *tk, const struct timespec *ts) |
| 109 | { |
| 110 | tk->xtime_sec = ts->tv_sec; |
John Stultz | b44d50d | 2012-07-23 16:22:37 -0400 | [diff] [blame] | 111 | tk->xtime_nsec = (u64)ts->tv_nsec << tk->shift; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 112 | } |
| 113 | |
| 114 | static void tk_xtime_add(struct timekeeper *tk, const struct timespec *ts) |
| 115 | { |
| 116 | tk->xtime_sec += ts->tv_sec; |
John Stultz | b44d50d | 2012-07-23 16:22:37 -0400 | [diff] [blame] | 117 | tk->xtime_nsec += (u64)ts->tv_nsec << tk->shift; |
John Stultz | 784ffcb | 2012-08-21 20:30:46 -0400 | [diff] [blame] | 118 | tk_normalize_xtime(tk); |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 119 | } |
John Stultz | 8fcce54 | 2011-11-14 11:46:39 -0800 | [diff] [blame] | 120 | |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 121 | static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec wtm) |
| 122 | { |
| 123 | struct timespec tmp; |
| 124 | |
| 125 | /* |
| 126 | * Verify consistency of: offset_real = -wall_to_monotonic |
| 127 | * before modifying anything |
| 128 | */ |
| 129 | set_normalized_timespec(&tmp, -tk->wall_to_monotonic.tv_sec, |
| 130 | -tk->wall_to_monotonic.tv_nsec); |
| 131 | WARN_ON_ONCE(tk->offs_real.tv64 != timespec_to_ktime(tmp).tv64); |
| 132 | tk->wall_to_monotonic = wtm; |
| 133 | set_normalized_timespec(&tmp, -wtm.tv_sec, -wtm.tv_nsec); |
| 134 | tk->offs_real = timespec_to_ktime(tmp); |
| 135 | } |
| 136 | |
| 137 | static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t) |
| 138 | { |
| 139 | /* Verify consistency before modifying */ |
| 140 | WARN_ON_ONCE(tk->offs_boot.tv64 != timespec_to_ktime(tk->total_sleep_time).tv64); |
| 141 | |
| 142 | tk->total_sleep_time = t; |
| 143 | tk->offs_boot = timespec_to_ktime(t); |
| 144 | } |
| 145 | |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 146 | /** |
| 147 | * timekeeper_setup_internals - Set up internals to use clocksource clock. |
| 148 | * |
| 149 | * @clock: Pointer to clocksource. |
| 150 | * |
| 151 | * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment |
| 152 | * pair and interval request. |
| 153 | * |
| 154 | * Unless you're the timekeeping code, you should not be using this! |
| 155 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 156 | static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock) |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 157 | { |
| 158 | cycle_t interval; |
Kasper Pedersen | a386b5a | 2010-10-20 15:55:15 -0700 | [diff] [blame] | 159 | u64 tmp, ntpinterval; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 160 | struct clocksource *old_clock; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 161 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 162 | old_clock = tk->clock; |
| 163 | tk->clock = clock; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 164 | clock->cycle_last = clock->read(clock); |
| 165 | |
| 166 | /* Do the ns -> cycle conversion first, using original mult */ |
| 167 | tmp = NTP_INTERVAL_LENGTH; |
| 168 | tmp <<= clock->shift; |
Kasper Pedersen | a386b5a | 2010-10-20 15:55:15 -0700 | [diff] [blame] | 169 | ntpinterval = tmp; |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 170 | tmp += clock->mult/2; |
| 171 | do_div(tmp, clock->mult); |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 172 | if (tmp == 0) |
| 173 | tmp = 1; |
| 174 | |
| 175 | interval = (cycle_t) tmp; |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 176 | tk->cycle_interval = interval; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 177 | |
| 178 | /* Go back from cycles -> shifted ns */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 179 | tk->xtime_interval = (u64) interval * clock->mult; |
| 180 | tk->xtime_remainder = ntpinterval - tk->xtime_interval; |
| 181 | tk->raw_interval = |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 182 | ((u64) interval * clock->mult) >> clock->shift; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 183 | |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 184 | /* if changing clocks, convert xtime_nsec shift units */ |
| 185 | if (old_clock) { |
| 186 | int shift_change = clock->shift - old_clock->shift; |
| 187 | if (shift_change < 0) |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 188 | tk->xtime_nsec >>= -shift_change; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 189 | else |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 190 | tk->xtime_nsec <<= shift_change; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 191 | } |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 192 | tk->shift = clock->shift; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 193 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 194 | tk->ntp_error = 0; |
| 195 | tk->ntp_error_shift = NTP_SCALE_SHIFT - clock->shift; |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 196 | |
| 197 | /* |
| 198 | * The timekeeper keeps its own mult values for the currently |
| 199 | * active clocksource. These value will be adjusted via NTP |
| 200 | * to counteract clock drifting. |
| 201 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 202 | tk->mult = clock->mult; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 203 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 204 | |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 205 | /* Timekeeper helper functions. */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 206 | static inline s64 timekeeping_get_ns(struct timekeeper *tk) |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 207 | { |
| 208 | cycle_t cycle_now, cycle_delta; |
| 209 | struct clocksource *clock; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 210 | s64 nsec; |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 211 | |
| 212 | /* read clocksource: */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 213 | clock = tk->clock; |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 214 | cycle_now = clock->read(clock); |
| 215 | |
| 216 | /* calculate the delta since the last update_wall_time: */ |
| 217 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; |
| 218 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 219 | nsec = cycle_delta * tk->mult + tk->xtime_nsec; |
| 220 | nsec >>= tk->shift; |
John Stultz | f2a5a08 | 2012-07-13 01:21:55 -0400 | [diff] [blame] | 221 | |
| 222 | /* If arch requires, add in gettimeoffset() */ |
| 223 | return nsec + arch_gettimeoffset(); |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 224 | } |
| 225 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 226 | static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk) |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 227 | { |
| 228 | cycle_t cycle_now, cycle_delta; |
| 229 | struct clocksource *clock; |
John Stultz | f2a5a08 | 2012-07-13 01:21:55 -0400 | [diff] [blame] | 230 | s64 nsec; |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 231 | |
| 232 | /* read clocksource: */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 233 | clock = tk->clock; |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 234 | cycle_now = clock->read(clock); |
| 235 | |
| 236 | /* calculate the delta since the last update_wall_time: */ |
| 237 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; |
| 238 | |
John Stultz | f2a5a08 | 2012-07-13 01:21:55 -0400 | [diff] [blame] | 239 | /* convert delta to nanoseconds. */ |
| 240 | nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); |
| 241 | |
| 242 | /* If arch requires, add in gettimeoffset() */ |
| 243 | return nsec + arch_gettimeoffset(); |
Martin Schwidefsky | 2ba2a30 | 2009-08-14 15:47:29 +0200 | [diff] [blame] | 244 | } |
| 245 | |
Thomas Gleixner | cc06268 | 2011-11-13 23:19:49 +0000 | [diff] [blame] | 246 | /* must hold write on timekeeper.lock */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 247 | static void timekeeping_update(struct timekeeper *tk, bool clearntp) |
Thomas Gleixner | cc06268 | 2011-11-13 23:19:49 +0000 | [diff] [blame] | 248 | { |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 249 | struct timespec xt; |
| 250 | |
Thomas Gleixner | cc06268 | 2011-11-13 23:19:49 +0000 | [diff] [blame] | 251 | if (clearntp) { |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 252 | tk->ntp_error = 0; |
Thomas Gleixner | cc06268 | 2011-11-13 23:19:49 +0000 | [diff] [blame] | 253 | ntp_clear(); |
| 254 | } |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 255 | xt = tk_xtime(tk); |
| 256 | update_vsyscall(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult); |
Thomas Gleixner | cc06268 | 2011-11-13 23:19:49 +0000 | [diff] [blame] | 257 | } |
| 258 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 259 | /** |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 260 | * timekeeping_forward_now - update clock to the current time |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 261 | * |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 262 | * Forward the current clock to update its state since the last call to |
| 263 | * update_wall_time(). This is useful before significant clock changes, |
| 264 | * as it avoids having to deal with this time offset explicitly. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 265 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 266 | static void timekeeping_forward_now(struct timekeeper *tk) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 267 | { |
| 268 | cycle_t cycle_now, cycle_delta; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 269 | struct clocksource *clock; |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 270 | s64 nsec; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 271 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 272 | clock = tk->clock; |
Martin Schwidefsky | a0f7d48 | 2009-08-14 15:47:19 +0200 | [diff] [blame] | 273 | cycle_now = clock->read(clock); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 274 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; |
Roman Zippel | 9a05511 | 2008-08-20 16:37:28 -0700 | [diff] [blame] | 275 | clock->cycle_last = cycle_now; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 276 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 277 | tk->xtime_nsec += cycle_delta * tk->mult; |
john stultz | 7d27558 | 2009-05-01 13:10:26 -0700 | [diff] [blame] | 278 | |
| 279 | /* If arch requires, add in gettimeoffset() */ |
Andreas Schwab | 85dc8f0 | 2012-08-21 20:30:47 -0400 | [diff] [blame] | 280 | tk->xtime_nsec += (u64)arch_gettimeoffset() << tk->shift; |
john stultz | 7d27558 | 2009-05-01 13:10:26 -0700 | [diff] [blame] | 281 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 282 | tk_normalize_xtime(tk); |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 283 | |
Martin Schwidefsky | 0a54419 | 2009-08-14 15:47:28 +0200 | [diff] [blame] | 284 | nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 285 | timespec_add_ns(&tk->raw_time, nsec); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 286 | } |
| 287 | |
| 288 | /** |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 289 | * getnstimeofday - Returns the time of day in a timespec |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 290 | * @ts: pointer to the timespec to be set |
| 291 | * |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 292 | * Returns the time of day in a timespec. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 293 | */ |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 294 | void getnstimeofday(struct timespec *ts) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 295 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 296 | struct timekeeper *tk = &timekeeper; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 297 | unsigned long seq; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 298 | s64 nsecs = 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 299 | |
Thomas Gleixner | 1c5745a | 2008-12-22 23:05:28 +0100 | [diff] [blame] | 300 | WARN_ON(timekeeping_suspended); |
| 301 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 302 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 303 | seq = read_seqbegin(&tk->lock); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 304 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 305 | ts->tv_sec = tk->xtime_sec; |
| 306 | ts->tv_nsec = timekeeping_get_ns(tk); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 307 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 308 | } while (read_seqretry(&tk->lock, seq)); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 309 | |
| 310 | timespec_add_ns(ts, nsecs); |
| 311 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 312 | EXPORT_SYMBOL(getnstimeofday); |
| 313 | |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 314 | ktime_t ktime_get(void) |
| 315 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 316 | struct timekeeper *tk = &timekeeper; |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 317 | unsigned int seq; |
| 318 | s64 secs, nsecs; |
| 319 | |
| 320 | WARN_ON(timekeeping_suspended); |
| 321 | |
| 322 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 323 | seq = read_seqbegin(&tk->lock); |
| 324 | secs = tk->xtime_sec + tk->wall_to_monotonic.tv_sec; |
| 325 | nsecs = timekeeping_get_ns(tk) + tk->wall_to_monotonic.tv_nsec; |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 326 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 327 | } while (read_seqretry(&tk->lock, seq)); |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 328 | /* |
| 329 | * Use ktime_set/ktime_add_ns to create a proper ktime on |
| 330 | * 32-bit architectures without CONFIG_KTIME_SCALAR. |
| 331 | */ |
| 332 | return ktime_add_ns(ktime_set(secs, 0), nsecs); |
| 333 | } |
| 334 | EXPORT_SYMBOL_GPL(ktime_get); |
| 335 | |
| 336 | /** |
| 337 | * ktime_get_ts - get the monotonic clock in timespec format |
| 338 | * @ts: pointer to timespec variable |
| 339 | * |
| 340 | * The function calculates the monotonic clock from the realtime |
| 341 | * clock and the wall_to_monotonic offset and stores the result |
| 342 | * in normalized timespec format in the variable pointed to by @ts. |
| 343 | */ |
| 344 | void ktime_get_ts(struct timespec *ts) |
| 345 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 346 | struct timekeeper *tk = &timekeeper; |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 347 | struct timespec tomono; |
| 348 | unsigned int seq; |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 349 | |
| 350 | WARN_ON(timekeeping_suspended); |
| 351 | |
| 352 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 353 | seq = read_seqbegin(&tk->lock); |
| 354 | ts->tv_sec = tk->xtime_sec; |
| 355 | ts->tv_nsec = timekeeping_get_ns(tk); |
| 356 | tomono = tk->wall_to_monotonic; |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 357 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 358 | } while (read_seqretry(&tk->lock, seq)); |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 359 | |
| 360 | set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec, |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 361 | ts->tv_nsec + tomono.tv_nsec); |
Martin Schwidefsky | 951ed4d | 2009-07-07 11:27:28 +0200 | [diff] [blame] | 362 | } |
| 363 | EXPORT_SYMBOL_GPL(ktime_get_ts); |
| 364 | |
Alexander Gordeev | e2c18e4 | 2011-01-12 17:00:57 -0800 | [diff] [blame] | 365 | #ifdef CONFIG_NTP_PPS |
| 366 | |
| 367 | /** |
| 368 | * getnstime_raw_and_real - get day and raw monotonic time in timespec format |
| 369 | * @ts_raw: pointer to the timespec to be set to raw monotonic time |
| 370 | * @ts_real: pointer to the timespec to be set to the time of day |
| 371 | * |
| 372 | * This function reads both the time of day and raw monotonic time at the |
| 373 | * same time atomically and stores the resulting timestamps in timespec |
| 374 | * format. |
| 375 | */ |
| 376 | void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) |
| 377 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 378 | struct timekeeper *tk = &timekeeper; |
Alexander Gordeev | e2c18e4 | 2011-01-12 17:00:57 -0800 | [diff] [blame] | 379 | unsigned long seq; |
| 380 | s64 nsecs_raw, nsecs_real; |
| 381 | |
| 382 | WARN_ON_ONCE(timekeeping_suspended); |
| 383 | |
| 384 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 385 | seq = read_seqbegin(&tk->lock); |
Alexander Gordeev | e2c18e4 | 2011-01-12 17:00:57 -0800 | [diff] [blame] | 386 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 387 | *ts_raw = tk->raw_time; |
| 388 | ts_real->tv_sec = tk->xtime_sec; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 389 | ts_real->tv_nsec = 0; |
Alexander Gordeev | e2c18e4 | 2011-01-12 17:00:57 -0800 | [diff] [blame] | 390 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 391 | nsecs_raw = timekeeping_get_ns_raw(tk); |
| 392 | nsecs_real = timekeeping_get_ns(tk); |
Alexander Gordeev | e2c18e4 | 2011-01-12 17:00:57 -0800 | [diff] [blame] | 393 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 394 | } while (read_seqretry(&tk->lock, seq)); |
Alexander Gordeev | e2c18e4 | 2011-01-12 17:00:57 -0800 | [diff] [blame] | 395 | |
| 396 | timespec_add_ns(ts_raw, nsecs_raw); |
| 397 | timespec_add_ns(ts_real, nsecs_real); |
| 398 | } |
| 399 | EXPORT_SYMBOL(getnstime_raw_and_real); |
| 400 | |
| 401 | #endif /* CONFIG_NTP_PPS */ |
| 402 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 403 | /** |
| 404 | * do_gettimeofday - Returns the time of day in a timeval |
| 405 | * @tv: pointer to the timeval to be set |
| 406 | * |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 407 | * NOTE: Users should be converted to using getnstimeofday() |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 408 | */ |
| 409 | void do_gettimeofday(struct timeval *tv) |
| 410 | { |
| 411 | struct timespec now; |
| 412 | |
Geert Uytterhoeven | efd9ac8 | 2008-01-30 13:30:01 +0100 | [diff] [blame] | 413 | getnstimeofday(&now); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 414 | tv->tv_sec = now.tv_sec; |
| 415 | tv->tv_usec = now.tv_nsec/1000; |
| 416 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 417 | EXPORT_SYMBOL(do_gettimeofday); |
Richard Cochran | d239f49 | 2012-04-27 10:12:42 +0200 | [diff] [blame] | 418 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 419 | /** |
| 420 | * do_settimeofday - Sets the time of day |
| 421 | * @tv: pointer to the timespec variable containing the new time |
| 422 | * |
| 423 | * Sets the time of day to the new time and update NTP and notify hrtimers |
| 424 | */ |
Richard Cochran | 1e6d767 | 2011-02-01 13:50:58 +0000 | [diff] [blame] | 425 | int do_settimeofday(const struct timespec *tv) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 426 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 427 | struct timekeeper *tk = &timekeeper; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 428 | struct timespec ts_delta, xt; |
John Stultz | 92c1d3e | 2011-11-14 14:05:44 -0800 | [diff] [blame] | 429 | unsigned long flags; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 430 | |
John Stultz | cee5848 | 2012-08-31 13:30:06 -0400 | [diff] [blame^] | 431 | if (!timespec_valid_strict(tv)) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 432 | return -EINVAL; |
| 433 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 434 | write_seqlock_irqsave(&tk->lock, flags); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 435 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 436 | timekeeping_forward_now(tk); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 437 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 438 | xt = tk_xtime(tk); |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 439 | ts_delta.tv_sec = tv->tv_sec - xt.tv_sec; |
| 440 | ts_delta.tv_nsec = tv->tv_nsec - xt.tv_nsec; |
| 441 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 442 | tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, ts_delta)); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 443 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 444 | tk_set_xtime(tk, tv); |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 445 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 446 | timekeeping_update(tk, true); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 447 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 448 | write_sequnlock_irqrestore(&tk->lock, flags); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 449 | |
| 450 | /* signal hrtimers about time change */ |
| 451 | clock_was_set(); |
| 452 | |
| 453 | return 0; |
| 454 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 455 | EXPORT_SYMBOL(do_settimeofday); |
| 456 | |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 457 | /** |
| 458 | * timekeeping_inject_offset - Adds or subtracts from the current time. |
| 459 | * @tv: pointer to the timespec variable containing the offset |
| 460 | * |
| 461 | * Adds or subtracts an offset value from the current time. |
| 462 | */ |
| 463 | int timekeeping_inject_offset(struct timespec *ts) |
| 464 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 465 | struct timekeeper *tk = &timekeeper; |
John Stultz | 92c1d3e | 2011-11-14 14:05:44 -0800 | [diff] [blame] | 466 | unsigned long flags; |
John Stultz | 4e8b145 | 2012-08-08 15:36:20 -0400 | [diff] [blame] | 467 | struct timespec tmp; |
| 468 | int ret = 0; |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 469 | |
| 470 | if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) |
| 471 | return -EINVAL; |
| 472 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 473 | write_seqlock_irqsave(&tk->lock, flags); |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 474 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 475 | timekeeping_forward_now(tk); |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 476 | |
John Stultz | 4e8b145 | 2012-08-08 15:36:20 -0400 | [diff] [blame] | 477 | /* Make sure the proposed value is valid */ |
| 478 | tmp = timespec_add(tk_xtime(tk), *ts); |
John Stultz | cee5848 | 2012-08-31 13:30:06 -0400 | [diff] [blame^] | 479 | if (!timespec_valid_strict(&tmp)) { |
John Stultz | 4e8b145 | 2012-08-08 15:36:20 -0400 | [diff] [blame] | 480 | ret = -EINVAL; |
| 481 | goto error; |
| 482 | } |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 483 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 484 | tk_xtime_add(tk, ts); |
| 485 | tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *ts)); |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 486 | |
John Stultz | 4e8b145 | 2012-08-08 15:36:20 -0400 | [diff] [blame] | 487 | error: /* even if we error out, we forwarded the time, so call update */ |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 488 | timekeeping_update(tk, true); |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 489 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 490 | write_sequnlock_irqrestore(&tk->lock, flags); |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 491 | |
| 492 | /* signal hrtimers about time change */ |
| 493 | clock_was_set(); |
| 494 | |
John Stultz | 4e8b145 | 2012-08-08 15:36:20 -0400 | [diff] [blame] | 495 | return ret; |
John Stultz | c528f7c | 2011-02-01 13:52:17 +0000 | [diff] [blame] | 496 | } |
| 497 | EXPORT_SYMBOL(timekeeping_inject_offset); |
| 498 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 499 | /** |
| 500 | * change_clocksource - Swaps clocksources if a new one is available |
| 501 | * |
| 502 | * Accumulates current time interval and initializes new clocksource |
| 503 | */ |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 504 | static int change_clocksource(void *data) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 505 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 506 | struct timekeeper *tk = &timekeeper; |
Magnus Damm | 4614e6a | 2009-04-21 12:24:02 -0700 | [diff] [blame] | 507 | struct clocksource *new, *old; |
John Stultz | f695cf9 | 2012-03-14 16:38:15 -0700 | [diff] [blame] | 508 | unsigned long flags; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 509 | |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 510 | new = (struct clocksource *) data; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 511 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 512 | write_seqlock_irqsave(&tk->lock, flags); |
John Stultz | f695cf9 | 2012-03-14 16:38:15 -0700 | [diff] [blame] | 513 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 514 | timekeeping_forward_now(tk); |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 515 | if (!new->enable || new->enable(new) == 0) { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 516 | old = tk->clock; |
| 517 | tk_setup_internals(tk, new); |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 518 | if (old->disable) |
| 519 | old->disable(old); |
| 520 | } |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 521 | timekeeping_update(tk, true); |
John Stultz | f695cf9 | 2012-03-14 16:38:15 -0700 | [diff] [blame] | 522 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 523 | write_sequnlock_irqrestore(&tk->lock, flags); |
John Stultz | f695cf9 | 2012-03-14 16:38:15 -0700 | [diff] [blame] | 524 | |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 525 | return 0; |
| 526 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 527 | |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 528 | /** |
| 529 | * timekeeping_notify - Install a new clock source |
| 530 | * @clock: pointer to the clock source |
| 531 | * |
| 532 | * This function is called from clocksource.c after a new, better clock |
| 533 | * source has been registered. The caller holds the clocksource_mutex. |
| 534 | */ |
| 535 | void timekeeping_notify(struct clocksource *clock) |
| 536 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 537 | struct timekeeper *tk = &timekeeper; |
| 538 | |
| 539 | if (tk->clock == clock) |
Magnus Damm | 4614e6a | 2009-04-21 12:24:02 -0700 | [diff] [blame] | 540 | return; |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 541 | stop_machine(change_clocksource, clock, NULL); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 542 | tick_clock_notify(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 543 | } |
Martin Schwidefsky | 75c5158 | 2009-08-14 15:47:30 +0200 | [diff] [blame] | 544 | |
Thomas Gleixner | a40f262 | 2009-07-07 13:00:31 +0200 | [diff] [blame] | 545 | /** |
| 546 | * ktime_get_real - get the real (wall-) time in ktime_t format |
| 547 | * |
| 548 | * returns the time in ktime_t format |
| 549 | */ |
| 550 | ktime_t ktime_get_real(void) |
| 551 | { |
| 552 | struct timespec now; |
| 553 | |
| 554 | getnstimeofday(&now); |
| 555 | |
| 556 | return timespec_to_ktime(now); |
| 557 | } |
| 558 | EXPORT_SYMBOL_GPL(ktime_get_real); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 559 | |
| 560 | /** |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 561 | * getrawmonotonic - Returns the raw monotonic time in a timespec |
| 562 | * @ts: pointer to the timespec to be set |
| 563 | * |
| 564 | * Returns the raw monotonic time (completely un-modified by ntp) |
| 565 | */ |
| 566 | void getrawmonotonic(struct timespec *ts) |
| 567 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 568 | struct timekeeper *tk = &timekeeper; |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 569 | unsigned long seq; |
| 570 | s64 nsecs; |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 571 | |
| 572 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 573 | seq = read_seqbegin(&tk->lock); |
| 574 | nsecs = timekeeping_get_ns_raw(tk); |
| 575 | *ts = tk->raw_time; |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 576 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 577 | } while (read_seqretry(&tk->lock, seq)); |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 578 | |
| 579 | timespec_add_ns(ts, nsecs); |
| 580 | } |
| 581 | EXPORT_SYMBOL(getrawmonotonic); |
| 582 | |
John Stultz | 2d42244 | 2008-08-20 16:37:30 -0700 | [diff] [blame] | 583 | /** |
Li Zefan | cf4fc6c | 2008-02-08 04:19:24 -0800 | [diff] [blame] | 584 | * timekeeping_valid_for_hres - Check if timekeeping is suitable for hres |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 585 | */ |
Li Zefan | cf4fc6c | 2008-02-08 04:19:24 -0800 | [diff] [blame] | 586 | int timekeeping_valid_for_hres(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 587 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 588 | struct timekeeper *tk = &timekeeper; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 589 | unsigned long seq; |
| 590 | int ret; |
| 591 | |
| 592 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 593 | seq = read_seqbegin(&tk->lock); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 594 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 595 | ret = tk->clock->flags & CLOCK_SOURCE_VALID_FOR_HRES; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 596 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 597 | } while (read_seqretry(&tk->lock, seq)); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 598 | |
| 599 | return ret; |
| 600 | } |
| 601 | |
| 602 | /** |
Jon Hunter | 9896246 | 2009-08-18 12:45:10 -0500 | [diff] [blame] | 603 | * timekeeping_max_deferment - Returns max time the clocksource can be deferred |
Jon Hunter | 9896246 | 2009-08-18 12:45:10 -0500 | [diff] [blame] | 604 | */ |
| 605 | u64 timekeeping_max_deferment(void) |
| 606 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 607 | struct timekeeper *tk = &timekeeper; |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 608 | unsigned long seq; |
| 609 | u64 ret; |
John Stultz | 42e71e8 | 2012-07-13 01:21:51 -0400 | [diff] [blame] | 610 | |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 611 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 612 | seq = read_seqbegin(&tk->lock); |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 613 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 614 | ret = tk->clock->max_idle_ns; |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 615 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 616 | } while (read_seqretry(&tk->lock, seq)); |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 617 | |
| 618 | return ret; |
Jon Hunter | 9896246 | 2009-08-18 12:45:10 -0500 | [diff] [blame] | 619 | } |
| 620 | |
| 621 | /** |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 622 | * read_persistent_clock - Return time from the persistent clock. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 623 | * |
| 624 | * Weak dummy function for arches that do not yet support it. |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 625 | * Reads the time from the battery backed persistent clock. |
| 626 | * 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] | 627 | * |
| 628 | * XXX - Do be sure to remove it once all arches implement it. |
| 629 | */ |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 630 | void __attribute__((weak)) read_persistent_clock(struct timespec *ts) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 631 | { |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 632 | ts->tv_sec = 0; |
| 633 | ts->tv_nsec = 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 634 | } |
| 635 | |
Martin Schwidefsky | 23970e3 | 2009-08-14 15:47:32 +0200 | [diff] [blame] | 636 | /** |
| 637 | * read_boot_clock - Return time of the system start. |
| 638 | * |
| 639 | * Weak dummy function for arches that do not yet support it. |
| 640 | * Function to read the exact time the system has been started. |
| 641 | * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported. |
| 642 | * |
| 643 | * XXX - Do be sure to remove it once all arches implement it. |
| 644 | */ |
| 645 | void __attribute__((weak)) read_boot_clock(struct timespec *ts) |
| 646 | { |
| 647 | ts->tv_sec = 0; |
| 648 | ts->tv_nsec = 0; |
| 649 | } |
| 650 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 651 | /* |
| 652 | * timekeeping_init - Initializes the clocksource and common timekeeping values |
| 653 | */ |
| 654 | void __init timekeeping_init(void) |
| 655 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 656 | struct timekeeper *tk = &timekeeper; |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 657 | struct clocksource *clock; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 658 | unsigned long flags; |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 659 | struct timespec now, boot, tmp; |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 660 | |
| 661 | read_persistent_clock(&now); |
John Stultz | cee5848 | 2012-08-31 13:30:06 -0400 | [diff] [blame^] | 662 | if (!timespec_valid_strict(&now)) { |
John Stultz | 4e8b145 | 2012-08-08 15:36:20 -0400 | [diff] [blame] | 663 | pr_warn("WARNING: Persistent clock returned invalid value!\n" |
| 664 | " Check your CMOS/BIOS settings.\n"); |
| 665 | now.tv_sec = 0; |
| 666 | now.tv_nsec = 0; |
| 667 | } |
| 668 | |
Martin Schwidefsky | 23970e3 | 2009-08-14 15:47:32 +0200 | [diff] [blame] | 669 | read_boot_clock(&boot); |
John Stultz | cee5848 | 2012-08-31 13:30:06 -0400 | [diff] [blame^] | 670 | if (!timespec_valid_strict(&boot)) { |
John Stultz | 4e8b145 | 2012-08-08 15:36:20 -0400 | [diff] [blame] | 671 | pr_warn("WARNING: Boot clock returned invalid value!\n" |
| 672 | " Check your CMOS/BIOS settings.\n"); |
| 673 | boot.tv_sec = 0; |
| 674 | boot.tv_nsec = 0; |
| 675 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 676 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 677 | seqlock_init(&tk->lock); |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 678 | |
Roman Zippel | 7dffa3c | 2008-05-01 04:34:41 -0700 | [diff] [blame] | 679 | ntp_init(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 680 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 681 | write_seqlock_irqsave(&tk->lock, flags); |
Martin Schwidefsky | f1b8274 | 2009-08-14 15:47:21 +0200 | [diff] [blame] | 682 | clock = clocksource_default_clock(); |
Martin Schwidefsky | a0f7d48 | 2009-08-14 15:47:19 +0200 | [diff] [blame] | 683 | if (clock->enable) |
| 684 | clock->enable(clock); |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 685 | tk_setup_internals(tk, clock); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 686 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 687 | tk_set_xtime(tk, &now); |
| 688 | tk->raw_time.tv_sec = 0; |
| 689 | tk->raw_time.tv_nsec = 0; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 690 | if (boot.tv_sec == 0 && boot.tv_nsec == 0) |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 691 | boot = tk_xtime(tk); |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 692 | |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 693 | set_normalized_timespec(&tmp, -boot.tv_sec, -boot.tv_nsec); |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 694 | tk_set_wall_to_mono(tk, tmp); |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 695 | |
| 696 | tmp.tv_sec = 0; |
| 697 | tmp.tv_nsec = 0; |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 698 | tk_set_sleep_time(tk, tmp); |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 699 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 700 | write_sequnlock_irqrestore(&tk->lock, flags); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 701 | } |
| 702 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 703 | /* time in seconds when suspend began */ |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 704 | static struct timespec timekeeping_suspend_time; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 705 | |
| 706 | /** |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 707 | * __timekeeping_inject_sleeptime - Internal function to add sleep interval |
| 708 | * @delta: pointer to a timespec delta value |
| 709 | * |
| 710 | * Takes a timespec offset measuring a suspend interval and properly |
| 711 | * adds the sleep offset to the timekeeping variables. |
| 712 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 713 | static void __timekeeping_inject_sleeptime(struct timekeeper *tk, |
| 714 | struct timespec *delta) |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 715 | { |
John Stultz | cee5848 | 2012-08-31 13:30:06 -0400 | [diff] [blame^] | 716 | if (!timespec_valid_strict(delta)) { |
John Stultz | cbaa515 | 2011-07-20 15:42:55 -0700 | [diff] [blame] | 717 | printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid " |
John Stultz | cb5de2f8d | 2011-06-01 18:18:09 -0700 | [diff] [blame] | 718 | "sleep delta value!\n"); |
| 719 | return; |
| 720 | } |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 721 | tk_xtime_add(tk, delta); |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 722 | tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *delta)); |
| 723 | tk_set_sleep_time(tk, timespec_add(tk->total_sleep_time, *delta)); |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 724 | } |
| 725 | |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 726 | /** |
| 727 | * timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values |
| 728 | * @delta: pointer to a timespec delta value |
| 729 | * |
| 730 | * This hook is for architectures that cannot support read_persistent_clock |
| 731 | * because their RTC/persistent clock is only accessible when irqs are enabled. |
| 732 | * |
| 733 | * This function should only be called by rtc_resume(), and allows |
| 734 | * a suspend offset to be injected into the timekeeping values. |
| 735 | */ |
| 736 | void timekeeping_inject_sleeptime(struct timespec *delta) |
| 737 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 738 | struct timekeeper *tk = &timekeeper; |
John Stultz | 92c1d3e | 2011-11-14 14:05:44 -0800 | [diff] [blame] | 739 | unsigned long flags; |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 740 | struct timespec ts; |
| 741 | |
| 742 | /* Make sure we don't set the clock twice */ |
| 743 | read_persistent_clock(&ts); |
| 744 | if (!(ts.tv_sec == 0 && ts.tv_nsec == 0)) |
| 745 | return; |
| 746 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 747 | write_seqlock_irqsave(&tk->lock, flags); |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 748 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 749 | timekeeping_forward_now(tk); |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 750 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 751 | __timekeeping_inject_sleeptime(tk, delta); |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 752 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 753 | timekeeping_update(tk, true); |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 754 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 755 | write_sequnlock_irqrestore(&tk->lock, flags); |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 756 | |
| 757 | /* signal hrtimers about time change */ |
| 758 | clock_was_set(); |
| 759 | } |
| 760 | |
John Stultz | 304529b | 2011-04-01 14:32:09 -0700 | [diff] [blame] | 761 | /** |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 762 | * timekeeping_resume - Resumes the generic timekeeping subsystem. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 763 | * |
| 764 | * This is for the generic clocksource timekeeping. |
| 765 | * xtime/wall_to_monotonic/jiffies/etc are |
| 766 | * still managed by arch specific suspend/resume code. |
| 767 | */ |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 768 | static void timekeeping_resume(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 769 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 770 | struct timekeeper *tk = &timekeeper; |
John Stultz | 92c1d3e | 2011-11-14 14:05:44 -0800 | [diff] [blame] | 771 | unsigned long flags; |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 772 | struct timespec ts; |
| 773 | |
| 774 | read_persistent_clock(&ts); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 775 | |
Thomas Gleixner | d10ff3f | 2007-05-14 11:10:02 +0200 | [diff] [blame] | 776 | clocksource_resume(); |
| 777 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 778 | write_seqlock_irqsave(&tk->lock, flags); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 779 | |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 780 | if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) { |
| 781 | ts = timespec_sub(ts, timekeeping_suspend_time); |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 782 | __timekeeping_inject_sleeptime(tk, &ts); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 783 | } |
| 784 | /* re-base the last cycle value */ |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 785 | tk->clock->cycle_last = tk->clock->read(tk->clock); |
| 786 | tk->ntp_error = 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 787 | timekeeping_suspended = 0; |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 788 | timekeeping_update(tk, false); |
| 789 | write_sequnlock_irqrestore(&tk->lock, flags); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 790 | |
| 791 | touch_softlockup_watchdog(); |
| 792 | |
| 793 | clockevents_notify(CLOCK_EVT_NOTIFY_RESUME, NULL); |
| 794 | |
| 795 | /* Resume hrtimers */ |
Thomas Gleixner | b12a03c | 2011-05-02 16:48:57 +0200 | [diff] [blame] | 796 | hrtimers_resume(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 797 | } |
| 798 | |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 799 | static int timekeeping_suspend(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 800 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 801 | struct timekeeper *tk = &timekeeper; |
John Stultz | 92c1d3e | 2011-11-14 14:05:44 -0800 | [diff] [blame] | 802 | unsigned long flags; |
John Stultz | cb33217 | 2011-05-31 22:53:23 -0700 | [diff] [blame] | 803 | struct timespec delta, delta_delta; |
| 804 | static struct timespec old_delta; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 805 | |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 806 | read_persistent_clock(&timekeeping_suspend_time); |
Thomas Gleixner | 3be9095 | 2007-09-16 15:36:43 +0200 | [diff] [blame] | 807 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 808 | write_seqlock_irqsave(&tk->lock, flags); |
| 809 | timekeeping_forward_now(tk); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 810 | timekeeping_suspended = 1; |
John Stultz | cb33217 | 2011-05-31 22:53:23 -0700 | [diff] [blame] | 811 | |
| 812 | /* |
| 813 | * To avoid drift caused by repeated suspend/resumes, |
| 814 | * which each can add ~1 second drift error, |
| 815 | * try to compensate so the difference in system time |
| 816 | * and persistent_clock time stays close to constant. |
| 817 | */ |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 818 | delta = timespec_sub(tk_xtime(tk), timekeeping_suspend_time); |
John Stultz | cb33217 | 2011-05-31 22:53:23 -0700 | [diff] [blame] | 819 | delta_delta = timespec_sub(delta, old_delta); |
| 820 | if (abs(delta_delta.tv_sec) >= 2) { |
| 821 | /* |
| 822 | * if delta_delta is too large, assume time correction |
| 823 | * has occured and set old_delta to the current delta. |
| 824 | */ |
| 825 | old_delta = delta; |
| 826 | } else { |
| 827 | /* Otherwise try to adjust old_system to compensate */ |
| 828 | timekeeping_suspend_time = |
| 829 | timespec_add(timekeeping_suspend_time, delta_delta); |
| 830 | } |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 831 | write_sequnlock_irqrestore(&tk->lock, flags); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 832 | |
| 833 | clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL); |
Magnus Damm | c54a42b | 2010-02-02 14:41:41 -0800 | [diff] [blame] | 834 | clocksource_suspend(); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 835 | |
| 836 | return 0; |
| 837 | } |
| 838 | |
| 839 | /* sysfs resume/suspend bits for timekeeping */ |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 840 | static struct syscore_ops timekeeping_syscore_ops = { |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 841 | .resume = timekeeping_resume, |
| 842 | .suspend = timekeeping_suspend, |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 843 | }; |
| 844 | |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 845 | static int __init timekeeping_init_ops(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 846 | { |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 847 | register_syscore_ops(&timekeeping_syscore_ops); |
| 848 | return 0; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 849 | } |
| 850 | |
Rafael J. Wysocki | e1a85b2 | 2011-03-23 22:16:04 +0100 | [diff] [blame] | 851 | device_initcall(timekeeping_init_ops); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 852 | |
| 853 | /* |
| 854 | * If the error is already larger, we look ahead even further |
| 855 | * to compensate for late or lost adjustments. |
| 856 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 857 | static __always_inline int timekeeping_bigadjust(struct timekeeper *tk, |
| 858 | s64 error, s64 *interval, |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 859 | s64 *offset) |
| 860 | { |
| 861 | s64 tick_error, i; |
| 862 | u32 look_ahead, adj; |
| 863 | s32 error2, mult; |
| 864 | |
| 865 | /* |
| 866 | * Use the current error value to determine how much to look ahead. |
| 867 | * The larger the error the slower we adjust for it to avoid problems |
| 868 | * with losing too many ticks, otherwise we would overadjust and |
| 869 | * produce an even larger error. The smaller the adjustment the |
| 870 | * 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] | 871 | * 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] | 872 | * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks). |
| 873 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 874 | error2 = tk->ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 875 | error2 = abs(error2); |
| 876 | for (look_ahead = 0; error2 > 0; look_ahead++) |
| 877 | error2 >>= 2; |
| 878 | |
| 879 | /* |
| 880 | * Now calculate the error in (1 << look_ahead) ticks, but first |
| 881 | * remove the single look ahead already included in the error. |
| 882 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 883 | tick_error = ntp_tick_length() >> (tk->ntp_error_shift + 1); |
| 884 | tick_error -= tk->xtime_interval >> 1; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 885 | error = ((error - tick_error) >> look_ahead) + tick_error; |
| 886 | |
| 887 | /* Finally calculate the adjustment shift value. */ |
| 888 | i = *interval; |
| 889 | mult = 1; |
| 890 | if (error < 0) { |
| 891 | error = -error; |
| 892 | *interval = -*interval; |
| 893 | *offset = -*offset; |
| 894 | mult = -1; |
| 895 | } |
| 896 | for (adj = 0; error > i; adj++) |
| 897 | error >>= 1; |
| 898 | |
| 899 | *interval <<= adj; |
| 900 | *offset <<= adj; |
| 901 | return mult << adj; |
| 902 | } |
| 903 | |
| 904 | /* |
| 905 | * Adjust the multiplier to reduce the error value, |
| 906 | * this is optimized for the most common adjustments of -1,0,1, |
| 907 | * for other values we can do a bit more work. |
| 908 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 909 | static void timekeeping_adjust(struct timekeeper *tk, s64 offset) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 910 | { |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 911 | s64 error, interval = tk->cycle_interval; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 912 | int adj; |
| 913 | |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 914 | /* |
Jim Cromie | 88b28ad | 2012-03-14 21:28:56 -0600 | [diff] [blame] | 915 | * The point of this is to check if the error is greater than half |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 916 | * an interval. |
| 917 | * |
| 918 | * First we shift it down from NTP_SHIFT to clocksource->shifted nsecs. |
| 919 | * |
| 920 | * Note we subtract one in the shift, so that error is really error*2. |
John Stultz | 3f86f28 | 2011-10-27 17:41:17 -0700 | [diff] [blame] | 921 | * This "saves" dividing(shifting) interval twice, but keeps the |
| 922 | * (error > interval) comparison as still measuring if error is |
Jim Cromie | 88b28ad | 2012-03-14 21:28:56 -0600 | [diff] [blame] | 923 | * larger than half an interval. |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 924 | * |
John Stultz | 3f86f28 | 2011-10-27 17:41:17 -0700 | [diff] [blame] | 925 | * Note: It does not "save" on aggravation when reading the code. |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 926 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 927 | error = tk->ntp_error >> (tk->ntp_error_shift - 1); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 928 | if (error > interval) { |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 929 | /* |
| 930 | * We now divide error by 4(via shift), which checks if |
Jim Cromie | 88b28ad | 2012-03-14 21:28:56 -0600 | [diff] [blame] | 931 | * the error is greater than twice the interval. |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 932 | * If it is greater, we need a bigadjust, if its smaller, |
| 933 | * we can adjust by 1. |
| 934 | */ |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 935 | error >>= 2; |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 936 | /* |
| 937 | * XXX - In update_wall_time, we round up to the next |
| 938 | * nanosecond, and store the amount rounded up into |
| 939 | * the error. This causes the likely below to be unlikely. |
| 940 | * |
John Stultz | 3f86f28 | 2011-10-27 17:41:17 -0700 | [diff] [blame] | 941 | * The proper fix is to avoid rounding up by using |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 942 | * the high precision tk->xtime_nsec instead of |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 943 | * xtime.tv_nsec everywhere. Fixing this will take some |
| 944 | * time. |
| 945 | */ |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 946 | if (likely(error <= interval)) |
| 947 | adj = 1; |
| 948 | else |
Ingo Molnar | 1d17d17 | 2012-08-04 21:21:14 +0200 | [diff] [blame] | 949 | adj = timekeeping_bigadjust(tk, error, &interval, &offset); |
| 950 | } else { |
| 951 | if (error < -interval) { |
| 952 | /* See comment above, this is just switched for the negative */ |
| 953 | error >>= 2; |
| 954 | if (likely(error >= -interval)) { |
| 955 | adj = -1; |
| 956 | interval = -interval; |
| 957 | offset = -offset; |
| 958 | } else { |
| 959 | adj = timekeeping_bigadjust(tk, error, &interval, &offset); |
| 960 | } |
| 961 | } else { |
| 962 | goto out_adjust; |
| 963 | } |
| 964 | } |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 965 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 966 | if (unlikely(tk->clock->maxadj && |
| 967 | (tk->mult + adj > tk->clock->mult + tk->clock->maxadj))) { |
John Stultz | e919cfd | 2012-03-22 19:14:46 -0700 | [diff] [blame] | 968 | printk_once(KERN_WARNING |
| 969 | "Adjusting %s more than 11%% (%ld vs %ld)\n", |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 970 | tk->clock->name, (long)tk->mult + adj, |
| 971 | (long)tk->clock->mult + tk->clock->maxadj); |
John Stultz | e919cfd | 2012-03-22 19:14:46 -0700 | [diff] [blame] | 972 | } |
John Stultz | c2bc111 | 2011-10-27 18:12:42 -0700 | [diff] [blame] | 973 | /* |
| 974 | * So the following can be confusing. |
| 975 | * |
| 976 | * To keep things simple, lets assume adj == 1 for now. |
| 977 | * |
| 978 | * When adj != 1, remember that the interval and offset values |
| 979 | * have been appropriately scaled so the math is the same. |
| 980 | * |
| 981 | * The basic idea here is that we're increasing the multiplier |
| 982 | * by one, this causes the xtime_interval to be incremented by |
| 983 | * one cycle_interval. This is because: |
| 984 | * xtime_interval = cycle_interval * mult |
| 985 | * So if mult is being incremented by one: |
| 986 | * xtime_interval = cycle_interval * (mult + 1) |
| 987 | * Its the same as: |
| 988 | * xtime_interval = (cycle_interval * mult) + cycle_interval |
| 989 | * Which can be shortened to: |
| 990 | * xtime_interval += cycle_interval |
| 991 | * |
| 992 | * So offset stores the non-accumulated cycles. Thus the current |
| 993 | * time (in shifted nanoseconds) is: |
| 994 | * now = (offset * adj) + xtime_nsec |
| 995 | * Now, even though we're adjusting the clock frequency, we have |
| 996 | * to keep time consistent. In other words, we can't jump back |
| 997 | * in time, and we also want to avoid jumping forward in time. |
| 998 | * |
| 999 | * So given the same offset value, we need the time to be the same |
| 1000 | * both before and after the freq adjustment. |
| 1001 | * now = (offset * adj_1) + xtime_nsec_1 |
| 1002 | * now = (offset * adj_2) + xtime_nsec_2 |
| 1003 | * So: |
| 1004 | * (offset * adj_1) + xtime_nsec_1 = |
| 1005 | * (offset * adj_2) + xtime_nsec_2 |
| 1006 | * And we know: |
| 1007 | * adj_2 = adj_1 + 1 |
| 1008 | * So: |
| 1009 | * (offset * adj_1) + xtime_nsec_1 = |
| 1010 | * (offset * (adj_1+1)) + xtime_nsec_2 |
| 1011 | * (offset * adj_1) + xtime_nsec_1 = |
| 1012 | * (offset * adj_1) + offset + xtime_nsec_2 |
| 1013 | * Canceling the sides: |
| 1014 | * xtime_nsec_1 = offset + xtime_nsec_2 |
| 1015 | * Which gives us: |
| 1016 | * xtime_nsec_2 = xtime_nsec_1 - offset |
| 1017 | * Which simplfies to: |
| 1018 | * xtime_nsec -= offset |
| 1019 | * |
| 1020 | * XXX - TODO: Doc ntp_error calculation. |
| 1021 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1022 | tk->mult += adj; |
| 1023 | tk->xtime_interval += interval; |
| 1024 | tk->xtime_nsec -= offset; |
| 1025 | tk->ntp_error -= (interval - offset) << tk->ntp_error_shift; |
John Stultz | 2a8c088 | 2012-07-13 01:21:56 -0400 | [diff] [blame] | 1026 | |
Ingo Molnar | 1d17d17 | 2012-08-04 21:21:14 +0200 | [diff] [blame] | 1027 | out_adjust: |
John Stultz | 2a8c088 | 2012-07-13 01:21:56 -0400 | [diff] [blame] | 1028 | /* |
| 1029 | * It may be possible that when we entered this function, xtime_nsec |
| 1030 | * was very small. Further, if we're slightly speeding the clocksource |
| 1031 | * in the code above, its possible the required corrective factor to |
| 1032 | * xtime_nsec could cause it to underflow. |
| 1033 | * |
| 1034 | * Now, since we already accumulated the second, cannot simply roll |
| 1035 | * the accumulated second back, since the NTP subsystem has been |
| 1036 | * notified via second_overflow. So instead we push xtime_nsec forward |
| 1037 | * by the amount we underflowed, and add that amount into the error. |
| 1038 | * |
| 1039 | * We'll correct this error next time through this function, when |
| 1040 | * xtime_nsec is not as small. |
| 1041 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1042 | if (unlikely((s64)tk->xtime_nsec < 0)) { |
| 1043 | s64 neg = -(s64)tk->xtime_nsec; |
| 1044 | tk->xtime_nsec = 0; |
| 1045 | tk->ntp_error += neg << tk->ntp_error_shift; |
John Stultz | 2a8c088 | 2012-07-13 01:21:56 -0400 | [diff] [blame] | 1046 | } |
| 1047 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1048 | } |
| 1049 | |
| 1050 | /** |
John Stultz | 1f4f948 | 2012-07-13 01:21:54 -0400 | [diff] [blame] | 1051 | * accumulate_nsecs_to_secs - Accumulates nsecs into secs |
| 1052 | * |
| 1053 | * Helper function that accumulates a the nsecs greater then a second |
| 1054 | * from the xtime_nsec field to the xtime_secs field. |
| 1055 | * It also calls into the NTP code to handle leapsecond processing. |
| 1056 | * |
| 1057 | */ |
| 1058 | static inline void accumulate_nsecs_to_secs(struct timekeeper *tk) |
| 1059 | { |
| 1060 | u64 nsecps = (u64)NSEC_PER_SEC << tk->shift; |
| 1061 | |
| 1062 | while (tk->xtime_nsec >= nsecps) { |
| 1063 | int leap; |
| 1064 | |
| 1065 | tk->xtime_nsec -= nsecps; |
| 1066 | tk->xtime_sec++; |
| 1067 | |
| 1068 | /* Figure out if its a leap sec and apply if needed */ |
| 1069 | leap = second_overflow(tk->xtime_sec); |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 1070 | if (unlikely(leap)) { |
| 1071 | struct timespec ts; |
John Stultz | 1f4f948 | 2012-07-13 01:21:54 -0400 | [diff] [blame] | 1072 | |
John Stultz | 6d0ef90 | 2012-07-27 14:48:12 -0400 | [diff] [blame] | 1073 | tk->xtime_sec += leap; |
| 1074 | |
| 1075 | ts.tv_sec = leap; |
| 1076 | ts.tv_nsec = 0; |
| 1077 | tk_set_wall_to_mono(tk, |
| 1078 | timespec_sub(tk->wall_to_monotonic, ts)); |
| 1079 | |
| 1080 | clock_was_set_delayed(); |
| 1081 | } |
John Stultz | 1f4f948 | 2012-07-13 01:21:54 -0400 | [diff] [blame] | 1082 | } |
| 1083 | } |
| 1084 | |
John Stultz | 1f4f948 | 2012-07-13 01:21:54 -0400 | [diff] [blame] | 1085 | /** |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1086 | * logarithmic_accumulation - shifted accumulation of cycles |
| 1087 | * |
| 1088 | * This functions accumulates a shifted interval of cycles into |
| 1089 | * into a shifted interval nanoseconds. Allows for O(log) accumulation |
| 1090 | * loop. |
| 1091 | * |
| 1092 | * Returns the unconsumed cycles. |
| 1093 | */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1094 | static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, |
| 1095 | u32 shift) |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1096 | { |
Jason Wessel | deda2e8 | 2010-08-09 14:20:09 -0700 | [diff] [blame] | 1097 | u64 raw_nsecs; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1098 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1099 | /* If the offset is smaller then a shifted interval, do nothing */ |
| 1100 | if (offset < tk->cycle_interval<<shift) |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1101 | return offset; |
| 1102 | |
| 1103 | /* Accumulate one shifted interval */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1104 | offset -= tk->cycle_interval << shift; |
| 1105 | tk->clock->cycle_last += tk->cycle_interval << shift; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1106 | |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1107 | tk->xtime_nsec += tk->xtime_interval << shift; |
| 1108 | accumulate_nsecs_to_secs(tk); |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1109 | |
Jason Wessel | deda2e8 | 2010-08-09 14:20:09 -0700 | [diff] [blame] | 1110 | /* Accumulate raw time */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1111 | raw_nsecs = tk->raw_interval << shift; |
| 1112 | raw_nsecs += tk->raw_time.tv_nsec; |
John Stultz | c7dcf87 | 2010-08-13 11:30:58 -0700 | [diff] [blame] | 1113 | if (raw_nsecs >= NSEC_PER_SEC) { |
| 1114 | u64 raw_secs = raw_nsecs; |
| 1115 | raw_nsecs = do_div(raw_secs, NSEC_PER_SEC); |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1116 | tk->raw_time.tv_sec += raw_secs; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1117 | } |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1118 | tk->raw_time.tv_nsec = raw_nsecs; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1119 | |
| 1120 | /* Accumulate error between NTP and clock interval */ |
John Stultz | f726a69 | 2012-07-13 01:21:57 -0400 | [diff] [blame] | 1121 | tk->ntp_error += ntp_tick_length() << shift; |
| 1122 | tk->ntp_error -= (tk->xtime_interval + tk->xtime_remainder) << |
| 1123 | (tk->ntp_error_shift + shift); |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1124 | |
| 1125 | return offset; |
| 1126 | } |
| 1127 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1128 | /** |
| 1129 | * update_wall_time - Uses the current clocksource to increment the wall time |
| 1130 | * |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1131 | */ |
Torben Hohn | 871cf1e | 2011-01-27 15:58:55 +0100 | [diff] [blame] | 1132 | static void update_wall_time(void) |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1133 | { |
Martin Schwidefsky | 155ec60 | 2009-08-14 15:47:26 +0200 | [diff] [blame] | 1134 | struct clocksource *clock; |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1135 | struct timekeeper *tk = &timekeeper; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1136 | cycle_t offset; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1137 | int shift = 0, maxshift; |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 1138 | unsigned long flags; |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 1139 | s64 remainder; |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 1140 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1141 | write_seqlock_irqsave(&tk->lock, flags); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1142 | |
| 1143 | /* Make sure we're fully resumed: */ |
| 1144 | if (unlikely(timekeeping_suspended)) |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 1145 | goto out; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1146 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1147 | clock = tk->clock; |
John Stultz | 592913e | 2010-07-13 17:56:20 -0700 | [diff] [blame] | 1148 | |
| 1149 | #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1150 | offset = tk->cycle_interval; |
John Stultz | 592913e | 2010-07-13 17:56:20 -0700 | [diff] [blame] | 1151 | #else |
| 1152 | offset = (clock->read(clock) - clock->cycle_last) & clock->mask; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1153 | #endif |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1154 | |
John Stultz | bf2ac31 | 2012-08-21 20:30:49 -0400 | [diff] [blame] | 1155 | /* Check if there's really nothing to do */ |
| 1156 | if (offset < tk->cycle_interval) |
| 1157 | goto out; |
| 1158 | |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1159 | /* |
| 1160 | * With NO_HZ we may have to accumulate many cycle_intervals |
| 1161 | * (think "ticks") worth of time at once. To do this efficiently, |
| 1162 | * we calculate the largest doubling multiple of cycle_intervals |
Jim Cromie | 88b28ad | 2012-03-14 21:28:56 -0600 | [diff] [blame] | 1163 | * that is smaller than the offset. We then accumulate that |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1164 | * chunk in one go, and then try to consume the next smaller |
| 1165 | * doubled multiple. |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1166 | */ |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1167 | shift = ilog2(offset) - ilog2(tk->cycle_interval); |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1168 | shift = max(0, shift); |
Jim Cromie | 88b28ad | 2012-03-14 21:28:56 -0600 | [diff] [blame] | 1169 | /* Bound shift to one less than what overflows tick_length */ |
John Stultz | ea7cf49 | 2011-11-14 13:18:07 -0800 | [diff] [blame] | 1170 | maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1; |
john stultz | a092ff0 | 2009-10-02 16:17:53 -0700 | [diff] [blame] | 1171 | shift = min(shift, maxshift); |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1172 | while (offset >= tk->cycle_interval) { |
| 1173 | offset = logarithmic_accumulation(tk, offset, shift); |
| 1174 | if (offset < tk->cycle_interval<<shift) |
John Stultz | 830ec04 | 2010-03-18 14:47:30 -0700 | [diff] [blame] | 1175 | shift--; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1176 | } |
| 1177 | |
| 1178 | /* correct the clock when NTP error is too big */ |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1179 | timekeeping_adjust(tk, offset); |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1180 | |
john stultz | 6c9bacb | 2008-12-01 18:34:41 -0800 | [diff] [blame] | 1181 | |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 1182 | /* |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 1183 | * Store only full nanoseconds into xtime_nsec after rounding |
| 1184 | * it up and add the remainder to the error difference. |
| 1185 | * XXX - This is necessary to avoid small 1ns inconsistnecies caused |
| 1186 | * by truncating the remainder in vsyscalls. However, it causes |
| 1187 | * additional work to be done in timekeeping_adjust(). Once |
| 1188 | * the vsyscall implementations are converted to use xtime_nsec |
| 1189 | * (shifted nanoseconds), this can be killed. |
| 1190 | */ |
John Stultz | 6ea565a | 2012-08-21 20:30:48 -0400 | [diff] [blame] | 1191 | remainder = tk->xtime_nsec & ((1ULL << tk->shift) - 1); |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1192 | tk->xtime_nsec -= remainder; |
John Stultz | 6ea565a | 2012-08-21 20:30:48 -0400 | [diff] [blame] | 1193 | tk->xtime_nsec += 1ULL << tk->shift; |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1194 | tk->ntp_error += remainder << tk->ntp_error_shift; |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1195 | |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 1196 | /* |
| 1197 | * Finally, make sure that after the rounding |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 1198 | * xtime_nsec isn't larger than NSEC_PER_SEC |
John Stultz | 6a867a3 | 2010-04-06 14:30:51 -0700 | [diff] [blame] | 1199 | */ |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1200 | accumulate_nsecs_to_secs(tk); |
Linus Torvalds | 83f57a1 | 2009-12-22 14:10:37 -0800 | [diff] [blame] | 1201 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1202 | timekeeping_update(tk, false); |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 1203 | |
| 1204 | out: |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1205 | write_sequnlock_irqrestore(&tk->lock, flags); |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 1206 | |
john stultz | 8524070 | 2007-05-08 00:27:59 -0700 | [diff] [blame] | 1207 | } |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 1208 | |
| 1209 | /** |
| 1210 | * getboottime - Return the real time of system boot. |
| 1211 | * @ts: pointer to the timespec to be set |
| 1212 | * |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 1213 | * Returns the wall-time of boot in a timespec. |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 1214 | * |
| 1215 | * This is based on the wall_to_monotonic offset and the total suspend |
| 1216 | * time. Calls to settimeofday will affect the value returned (which |
| 1217 | * basically means that however wrong your real time clock is at boot time, |
| 1218 | * you get the right time here). |
| 1219 | */ |
| 1220 | void getboottime(struct timespec *ts) |
| 1221 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1222 | struct timekeeper *tk = &timekeeper; |
Hiroshi Shimamoto | 36d4748 | 2009-08-25 15:08:30 +0900 | [diff] [blame] | 1223 | struct timespec boottime = { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1224 | .tv_sec = tk->wall_to_monotonic.tv_sec + |
| 1225 | tk->total_sleep_time.tv_sec, |
| 1226 | .tv_nsec = tk->wall_to_monotonic.tv_nsec + |
| 1227 | tk->total_sleep_time.tv_nsec |
Hiroshi Shimamoto | 36d4748 | 2009-08-25 15:08:30 +0900 | [diff] [blame] | 1228 | }; |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 1229 | |
Martin Schwidefsky | d4f587c | 2009-08-14 15:47:31 +0200 | [diff] [blame] | 1230 | set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec); |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 1231 | } |
Jason Wang | c93d89f | 2010-01-27 19:13:40 +0800 | [diff] [blame] | 1232 | EXPORT_SYMBOL_GPL(getboottime); |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 1233 | |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 1234 | /** |
| 1235 | * get_monotonic_boottime - Returns monotonic time since boot |
| 1236 | * @ts: pointer to the timespec to be set |
| 1237 | * |
| 1238 | * Returns the monotonic time since boot in a timespec. |
| 1239 | * |
| 1240 | * This is similar to CLOCK_MONTONIC/ktime_get_ts, but also |
| 1241 | * includes the time spent in suspend. |
| 1242 | */ |
| 1243 | void get_monotonic_boottime(struct timespec *ts) |
| 1244 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1245 | struct timekeeper *tk = &timekeeper; |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 1246 | struct timespec tomono, sleep; |
| 1247 | unsigned int seq; |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 1248 | |
| 1249 | WARN_ON(timekeeping_suspended); |
| 1250 | |
| 1251 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1252 | seq = read_seqbegin(&tk->lock); |
| 1253 | ts->tv_sec = tk->xtime_sec; |
| 1254 | ts->tv_nsec = timekeeping_get_ns(tk); |
| 1255 | tomono = tk->wall_to_monotonic; |
| 1256 | sleep = tk->total_sleep_time; |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 1257 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1258 | } while (read_seqretry(&tk->lock, seq)); |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 1259 | |
| 1260 | set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec + sleep.tv_sec, |
John Stultz | 1e75fa8 | 2012-07-13 01:21:53 -0400 | [diff] [blame] | 1261 | ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec); |
John Stultz | abb3a4e | 2011-02-14 17:52:09 -0800 | [diff] [blame] | 1262 | } |
| 1263 | EXPORT_SYMBOL_GPL(get_monotonic_boottime); |
| 1264 | |
| 1265 | /** |
| 1266 | * ktime_get_boottime - Returns monotonic time since boot in a ktime |
| 1267 | * |
| 1268 | * Returns the monotonic time since boot in a ktime |
| 1269 | * |
| 1270 | * This is similar to CLOCK_MONTONIC/ktime_get, but also |
| 1271 | * includes the time spent in suspend. |
| 1272 | */ |
| 1273 | ktime_t ktime_get_boottime(void) |
| 1274 | { |
| 1275 | struct timespec ts; |
| 1276 | |
| 1277 | get_monotonic_boottime(&ts); |
| 1278 | return timespec_to_ktime(ts); |
| 1279 | } |
| 1280 | EXPORT_SYMBOL_GPL(ktime_get_boottime); |
| 1281 | |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 1282 | /** |
| 1283 | * monotonic_to_bootbased - Convert the monotonic time to boot based. |
| 1284 | * @ts: pointer to the timespec to be converted |
| 1285 | */ |
| 1286 | void monotonic_to_bootbased(struct timespec *ts) |
| 1287 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1288 | struct timekeeper *tk = &timekeeper; |
| 1289 | |
| 1290 | *ts = timespec_add(*ts, tk->total_sleep_time); |
Tomas Janousek | 7c3f1a5 | 2007-07-15 23:39:41 -0700 | [diff] [blame] | 1291 | } |
Jason Wang | c93d89f | 2010-01-27 19:13:40 +0800 | [diff] [blame] | 1292 | EXPORT_SYMBOL_GPL(monotonic_to_bootbased); |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1293 | |
john stultz | 17c38b7 | 2007-07-24 18:38:34 -0700 | [diff] [blame] | 1294 | unsigned long get_seconds(void) |
| 1295 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1296 | struct timekeeper *tk = &timekeeper; |
| 1297 | |
| 1298 | return tk->xtime_sec; |
john stultz | 17c38b7 | 2007-07-24 18:38:34 -0700 | [diff] [blame] | 1299 | } |
| 1300 | EXPORT_SYMBOL(get_seconds); |
| 1301 | |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1302 | struct timespec __current_kernel_time(void) |
| 1303 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1304 | struct timekeeper *tk = &timekeeper; |
| 1305 | |
| 1306 | return tk_xtime(tk); |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1307 | } |
john stultz | 17c38b7 | 2007-07-24 18:38:34 -0700 | [diff] [blame] | 1308 | |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1309 | struct timespec current_kernel_time(void) |
| 1310 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1311 | struct timekeeper *tk = &timekeeper; |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1312 | struct timespec now; |
| 1313 | unsigned long seq; |
| 1314 | |
| 1315 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1316 | seq = read_seqbegin(&tk->lock); |
Linus Torvalds | 83f57a1 | 2009-12-22 14:10:37 -0800 | [diff] [blame] | 1317 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1318 | now = tk_xtime(tk); |
| 1319 | } while (read_seqretry(&tk->lock, seq)); |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1320 | |
| 1321 | return now; |
| 1322 | } |
john stultz | 2c6b47d | 2007-07-24 17:47:43 -0700 | [diff] [blame] | 1323 | EXPORT_SYMBOL(current_kernel_time); |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1324 | |
| 1325 | struct timespec get_monotonic_coarse(void) |
| 1326 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1327 | struct timekeeper *tk = &timekeeper; |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1328 | struct timespec now, mono; |
| 1329 | unsigned long seq; |
| 1330 | |
| 1331 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1332 | seq = read_seqbegin(&tk->lock); |
Linus Torvalds | 83f57a1 | 2009-12-22 14:10:37 -0800 | [diff] [blame] | 1333 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1334 | now = tk_xtime(tk); |
| 1335 | mono = tk->wall_to_monotonic; |
| 1336 | } while (read_seqretry(&tk->lock, seq)); |
john stultz | da15cfd | 2009-08-19 19:13:34 -0700 | [diff] [blame] | 1337 | |
| 1338 | set_normalized_timespec(&now, now.tv_sec + mono.tv_sec, |
| 1339 | now.tv_nsec + mono.tv_nsec); |
| 1340 | return now; |
| 1341 | } |
Torben Hohn | 871cf1e | 2011-01-27 15:58:55 +0100 | [diff] [blame] | 1342 | |
| 1343 | /* |
| 1344 | * The 64-bit jiffies value is not atomic - you MUST NOT read it |
| 1345 | * without sampling the sequence number in xtime_lock. |
| 1346 | * jiffies is defined in the linker script... |
| 1347 | */ |
| 1348 | void do_timer(unsigned long ticks) |
| 1349 | { |
| 1350 | jiffies_64 += ticks; |
| 1351 | update_wall_time(); |
| 1352 | calc_global_load(ticks); |
| 1353 | } |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1354 | |
| 1355 | /** |
John Stultz | 314ac37 | 2011-02-14 18:43:08 -0800 | [diff] [blame] | 1356 | * get_xtime_and_monotonic_and_sleep_offset() - get xtime, wall_to_monotonic, |
| 1357 | * and sleep offsets. |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1358 | * @xtim: pointer to timespec to be set with xtime |
| 1359 | * @wtom: pointer to timespec to be set with wall_to_monotonic |
John Stultz | 314ac37 | 2011-02-14 18:43:08 -0800 | [diff] [blame] | 1360 | * @sleep: pointer to timespec to be set with time in suspend |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1361 | */ |
John Stultz | 314ac37 | 2011-02-14 18:43:08 -0800 | [diff] [blame] | 1362 | void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim, |
| 1363 | struct timespec *wtom, struct timespec *sleep) |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1364 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1365 | struct timekeeper *tk = &timekeeper; |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1366 | unsigned long seq; |
| 1367 | |
| 1368 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1369 | seq = read_seqbegin(&tk->lock); |
| 1370 | *xtim = tk_xtime(tk); |
| 1371 | *wtom = tk->wall_to_monotonic; |
| 1372 | *sleep = tk->total_sleep_time; |
| 1373 | } while (read_seqretry(&tk->lock, seq)); |
Torben Hohn | 48cf76f7 | 2011-01-27 15:59:05 +0100 | [diff] [blame] | 1374 | } |
Torben Hohn | f0af911a9 | 2011-01-27 15:59:10 +0100 | [diff] [blame] | 1375 | |
Thomas Gleixner | f6c06ab | 2012-07-10 18:43:24 -0400 | [diff] [blame] | 1376 | #ifdef CONFIG_HIGH_RES_TIMERS |
| 1377 | /** |
| 1378 | * ktime_get_update_offsets - hrtimer helper |
| 1379 | * @offs_real: pointer to storage for monotonic -> realtime offset |
| 1380 | * @offs_boot: pointer to storage for monotonic -> boottime offset |
| 1381 | * |
| 1382 | * Returns current monotonic time and updates the offsets |
| 1383 | * Called from hrtimer_interupt() or retrigger_next_event() |
| 1384 | */ |
| 1385 | ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot) |
| 1386 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1387 | struct timekeeper *tk = &timekeeper; |
Thomas Gleixner | f6c06ab | 2012-07-10 18:43:24 -0400 | [diff] [blame] | 1388 | ktime_t now; |
| 1389 | unsigned int seq; |
| 1390 | u64 secs, nsecs; |
| 1391 | |
| 1392 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1393 | seq = read_seqbegin(&tk->lock); |
Thomas Gleixner | f6c06ab | 2012-07-10 18:43:24 -0400 | [diff] [blame] | 1394 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1395 | secs = tk->xtime_sec; |
| 1396 | nsecs = timekeeping_get_ns(tk); |
Thomas Gleixner | f6c06ab | 2012-07-10 18:43:24 -0400 | [diff] [blame] | 1397 | |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1398 | *offs_real = tk->offs_real; |
| 1399 | *offs_boot = tk->offs_boot; |
| 1400 | } while (read_seqretry(&tk->lock, seq)); |
Thomas Gleixner | f6c06ab | 2012-07-10 18:43:24 -0400 | [diff] [blame] | 1401 | |
| 1402 | now = ktime_add_ns(ktime_set(secs, 0), nsecs); |
| 1403 | now = ktime_sub(now, *offs_real); |
| 1404 | return now; |
| 1405 | } |
| 1406 | #endif |
| 1407 | |
Torben Hohn | f0af911a9 | 2011-01-27 15:59:10 +0100 | [diff] [blame] | 1408 | /** |
Thomas Gleixner | 99ee531 | 2011-04-27 14:16:42 +0200 | [diff] [blame] | 1409 | * ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format |
| 1410 | */ |
| 1411 | ktime_t ktime_get_monotonic_offset(void) |
| 1412 | { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1413 | struct timekeeper *tk = &timekeeper; |
Thomas Gleixner | 99ee531 | 2011-04-27 14:16:42 +0200 | [diff] [blame] | 1414 | unsigned long seq; |
| 1415 | struct timespec wtom; |
| 1416 | |
| 1417 | do { |
John Stultz | 4e250fd | 2012-07-27 14:48:13 -0400 | [diff] [blame] | 1418 | seq = read_seqbegin(&tk->lock); |
| 1419 | wtom = tk->wall_to_monotonic; |
| 1420 | } while (read_seqretry(&tk->lock, seq)); |
John Stultz | 70471f2 | 2011-11-14 12:48:10 -0800 | [diff] [blame] | 1421 | |
Thomas Gleixner | 99ee531 | 2011-04-27 14:16:42 +0200 | [diff] [blame] | 1422 | return timespec_to_ktime(wtom); |
| 1423 | } |
John Stultz | a80b83b | 2012-02-03 00:19:07 -0800 | [diff] [blame] | 1424 | EXPORT_SYMBOL_GPL(ktime_get_monotonic_offset); |
| 1425 | |
Thomas Gleixner | 99ee531 | 2011-04-27 14:16:42 +0200 | [diff] [blame] | 1426 | /** |
Torben Hohn | f0af911a9 | 2011-01-27 15:59:10 +0100 | [diff] [blame] | 1427 | * xtime_update() - advances the timekeeping infrastructure |
| 1428 | * @ticks: number of ticks, that have elapsed since the last call. |
| 1429 | * |
| 1430 | * Must be called with interrupts disabled. |
| 1431 | */ |
| 1432 | void xtime_update(unsigned long ticks) |
| 1433 | { |
| 1434 | write_seqlock(&xtime_lock); |
| 1435 | do_timer(ticks); |
| 1436 | write_sequnlock(&xtime_lock); |
| 1437 | } |