diff options
Diffstat (limited to 'kernel/time/timekeeping.c')
-rw-r--r-- | kernel/time/timekeeping.c | 208 |
1 files changed, 103 insertions, 105 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index aeeaab8cba6e..5980e902978c 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -127,14 +127,14 @@ static void tk_xtime_add(struct timekeeper *tk, const struct timespec *ts) * * Unless you're the timekeeping code, you should not be using this! */ -static void timekeeper_setup_internals(struct clocksource *clock) +static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock) { cycle_t interval; u64 tmp, ntpinterval; struct clocksource *old_clock; - old_clock = timekeeper.clock; - timekeeper.clock = clock; + old_clock = tk->clock; + tk->clock = clock; clock->cycle_last = clock->read(clock); /* Do the ns -> cycle conversion first, using original mult */ @@ -147,64 +147,64 @@ static void timekeeper_setup_internals(struct clocksource *clock) tmp = 1; interval = (cycle_t) tmp; - timekeeper.cycle_interval = interval; + tk->cycle_interval = interval; /* Go back from cycles -> shifted ns */ - timekeeper.xtime_interval = (u64) interval * clock->mult; - timekeeper.xtime_remainder = ntpinterval - timekeeper.xtime_interval; - timekeeper.raw_interval = + tk->xtime_interval = (u64) interval * clock->mult; + tk->xtime_remainder = ntpinterval - tk->xtime_interval; + tk->raw_interval = ((u64) interval * clock->mult) >> clock->shift; /* if changing clocks, convert xtime_nsec shift units */ if (old_clock) { int shift_change = clock->shift - old_clock->shift; if (shift_change < 0) - timekeeper.xtime_nsec >>= -shift_change; + tk->xtime_nsec >>= -shift_change; else - timekeeper.xtime_nsec <<= shift_change; + tk->xtime_nsec <<= shift_change; } - timekeeper.shift = clock->shift; + tk->shift = clock->shift; - timekeeper.ntp_error = 0; - timekeeper.ntp_error_shift = NTP_SCALE_SHIFT - clock->shift; + tk->ntp_error = 0; + tk->ntp_error_shift = NTP_SCALE_SHIFT - clock->shift; /* * The timekeeper keeps its own mult values for the currently * active clocksource. These value will be adjusted via NTP * to counteract clock drifting. */ - timekeeper.mult = clock->mult; + tk->mult = clock->mult; } /* Timekeeper helper functions. */ -static inline s64 timekeeping_get_ns(void) +static inline s64 timekeeping_get_ns(struct timekeeper *tk) { cycle_t cycle_now, cycle_delta; struct clocksource *clock; s64 nsec; /* read clocksource: */ - clock = timekeeper.clock; + clock = tk->clock; cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; - nsec = cycle_delta * timekeeper.mult + timekeeper.xtime_nsec; - nsec >>= timekeeper.shift; + nsec = cycle_delta * tk->mult + tk->xtime_nsec; + nsec >>= tk->shift; /* If arch requires, add in gettimeoffset() */ return nsec + arch_gettimeoffset(); } -static inline s64 timekeeping_get_ns_raw(void) +static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk) { cycle_t cycle_now, cycle_delta; struct clocksource *clock; s64 nsec; /* read clocksource: */ - clock = timekeeper.clock; + clock = tk->clock; cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ @@ -217,27 +217,26 @@ static inline s64 timekeeping_get_ns_raw(void) return nsec + arch_gettimeoffset(); } -static void update_rt_offset(void) +static void update_rt_offset(struct timekeeper *tk) { - struct timespec tmp, *wtm = &timekeeper.wall_to_monotonic; + struct timespec tmp, *wtm = &tk->wall_to_monotonic; set_normalized_timespec(&tmp, -wtm->tv_sec, -wtm->tv_nsec); - timekeeper.offs_real = timespec_to_ktime(tmp); + tk->offs_real = timespec_to_ktime(tmp); } /* must hold write on timekeeper.lock */ -static void timekeeping_update(bool clearntp) +static void timekeeping_update(struct timekeeper *tk, bool clearntp) { struct timespec xt; if (clearntp) { - timekeeper.ntp_error = 0; + tk->ntp_error = 0; ntp_clear(); } - update_rt_offset(); - xt = tk_xtime(&timekeeper); - update_vsyscall(&xt, &timekeeper.wall_to_monotonic, - timekeeper.clock, timekeeper.mult); + update_rt_offset(tk); + xt = tk_xtime(tk); + update_vsyscall(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult); } @@ -248,26 +247,26 @@ static void timekeeping_update(bool clearntp) * update_wall_time(). This is useful before significant clock changes, * as it avoids having to deal with this time offset explicitly. */ -static void timekeeping_forward_now(void) +static void timekeeping_forward_now(struct timekeeper *tk) { cycle_t cycle_now, cycle_delta; struct clocksource *clock; s64 nsec; - clock = timekeeper.clock; + clock = tk->clock; cycle_now = clock->read(clock); cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; clock->cycle_last = cycle_now; - timekeeper.xtime_nsec += cycle_delta * timekeeper.mult; + tk->xtime_nsec += cycle_delta * tk->mult; /* If arch requires, add in gettimeoffset() */ - timekeeper.xtime_nsec += arch_gettimeoffset() << timekeeper.shift; + tk->xtime_nsec += arch_gettimeoffset() << tk->shift; - tk_normalize_xtime(&timekeeper); + tk_normalize_xtime(tk); nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); - timespec_add_ns(&timekeeper.raw_time, nsec); + timespec_add_ns(&tk->raw_time, nsec); } /** @@ -287,7 +286,7 @@ void getnstimeofday(struct timespec *ts) seq = read_seqbegin(&timekeeper.lock); ts->tv_sec = timekeeper.xtime_sec; - ts->tv_nsec = timekeeping_get_ns(); + ts->tv_nsec = timekeeping_get_ns(&timekeeper); } while (read_seqretry(&timekeeper.lock, seq)); @@ -306,7 +305,7 @@ ktime_t ktime_get(void) seq = read_seqbegin(&timekeeper.lock); secs = timekeeper.xtime_sec + timekeeper.wall_to_monotonic.tv_sec; - nsecs = timekeeping_get_ns() + + nsecs = timekeeping_get_ns(&timekeeper) + timekeeper.wall_to_monotonic.tv_nsec; } while (read_seqretry(&timekeeper.lock, seq)); @@ -336,7 +335,7 @@ void ktime_get_ts(struct timespec *ts) do { seq = read_seqbegin(&timekeeper.lock); ts->tv_sec = timekeeper.xtime_sec; - ts->tv_nsec = timekeeping_get_ns(); + ts->tv_nsec = timekeeping_get_ns(&timekeeper); tomono = timekeeper.wall_to_monotonic; } while (read_seqretry(&timekeeper.lock, seq)); @@ -371,8 +370,8 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) ts_real->tv_sec = timekeeper.xtime_sec; ts_real->tv_nsec = 0; - nsecs_raw = timekeeping_get_ns_raw(); - nsecs_real = timekeeping_get_ns(); + nsecs_raw = timekeeping_get_ns_raw(&timekeeper); + nsecs_real = timekeeping_get_ns(&timekeeper); } while (read_seqretry(&timekeeper.lock, seq)); @@ -415,7 +414,7 @@ int do_settimeofday(const struct timespec *tv) write_seqlock_irqsave(&timekeeper.lock, flags); - timekeeping_forward_now(); + timekeeping_forward_now(&timekeeper); xt = tk_xtime(&timekeeper); ts_delta.tv_sec = tv->tv_sec - xt.tv_sec; @@ -426,7 +425,7 @@ int do_settimeofday(const struct timespec *tv) tk_set_xtime(&timekeeper, tv); - timekeeping_update(true); + timekeeping_update(&timekeeper, true); write_sequnlock_irqrestore(&timekeeper.lock, flags); @@ -453,14 +452,14 @@ int timekeeping_inject_offset(struct timespec *ts) write_seqlock_irqsave(&timekeeper.lock, flags); - timekeeping_forward_now(); + timekeeping_forward_now(&timekeeper); tk_xtime_add(&timekeeper, ts); timekeeper.wall_to_monotonic = timespec_sub(timekeeper.wall_to_monotonic, *ts); - timekeeping_update(true); + timekeeping_update(&timekeeper, true); write_sequnlock_irqrestore(&timekeeper.lock, flags); @@ -485,14 +484,14 @@ static int change_clocksource(void *data) write_seqlock_irqsave(&timekeeper.lock, flags); - timekeeping_forward_now(); + timekeeping_forward_now(&timekeeper); if (!new->enable || new->enable(new) == 0) { old = timekeeper.clock; - timekeeper_setup_internals(new); + tk_setup_internals(&timekeeper, new); if (old->disable) old->disable(old); } - timekeeping_update(true); + timekeeping_update(&timekeeper, true); write_sequnlock_irqrestore(&timekeeper.lock, flags); @@ -542,7 +541,7 @@ void getrawmonotonic(struct timespec *ts) do { seq = read_seqbegin(&timekeeper.lock); - nsecs = timekeeping_get_ns_raw(); + nsecs = timekeeping_get_ns_raw(&timekeeper); *ts = timekeeper.raw_time; } while (read_seqretry(&timekeeper.lock, seq)); @@ -638,7 +637,7 @@ void __init timekeeping_init(void) clock = clocksource_default_clock(); if (clock->enable) clock->enable(clock); - timekeeper_setup_internals(clock); + tk_setup_internals(&timekeeper, clock); tk_set_xtime(&timekeeper, &now); timekeeper.raw_time.tv_sec = 0; @@ -648,7 +647,7 @@ void __init timekeeping_init(void) set_normalized_timespec(&timekeeper.wall_to_monotonic, -boot.tv_sec, -boot.tv_nsec); - update_rt_offset(); + update_rt_offset(&timekeeper); timekeeper.total_sleep_time.tv_sec = 0; timekeeper.total_sleep_time.tv_nsec = 0; write_sequnlock_irqrestore(&timekeeper.lock, flags); @@ -670,7 +669,8 @@ static void update_sleep_time(struct timespec t) * Takes a timespec offset measuring a suspend interval and properly * adds the sleep offset to the timekeeping variables. */ -static void __timekeeping_inject_sleeptime(struct timespec *delta) +static void __timekeeping_inject_sleeptime(struct timekeeper *tk, + struct timespec *delta) { if (!timespec_valid(delta)) { printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid " @@ -678,10 +678,9 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta) return; } - tk_xtime_add(&timekeeper, delta); - timekeeper.wall_to_monotonic = - timespec_sub(timekeeper.wall_to_monotonic, *delta); - update_sleep_time(timespec_add(timekeeper.total_sleep_time, *delta)); + tk_xtime_add(tk, delta); + tk->wall_to_monotonic = timespec_sub(tk->wall_to_monotonic, *delta); + update_sleep_time(timespec_add(tk->total_sleep_time, *delta)); } @@ -707,11 +706,11 @@ void timekeeping_inject_sleeptime(struct timespec *delta) write_seqlock_irqsave(&timekeeper.lock, flags); - timekeeping_forward_now(); + timekeeping_forward_now(&timekeeper); - __timekeeping_inject_sleeptime(delta); + __timekeeping_inject_sleeptime(&timekeeper, delta); - timekeeping_update(true); + timekeeping_update(&timekeeper, true); write_sequnlock_irqrestore(&timekeeper.lock, flags); @@ -740,7 +739,7 @@ static void timekeeping_resume(void) if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) { ts = timespec_sub(ts, timekeeping_suspend_time); - __timekeeping_inject_sleeptime(&ts); + __timekeeping_inject_sleeptime(&timekeeper, &ts); } /* re-base the last cycle value */ timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock); @@ -765,7 +764,7 @@ static int timekeeping_suspend(void) read_persistent_clock(&timekeeping_suspend_time); write_seqlock_irqsave(&timekeeper.lock, flags); - timekeeping_forward_now(); + timekeeping_forward_now(&timekeeper); timekeeping_suspended = 1; /* @@ -813,7 +812,8 @@ device_initcall(timekeeping_init_ops); * If the error is already larger, we look ahead even further * to compensate for late or lost adjustments. */ -static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval, +static __always_inline int timekeeping_bigadjust(struct timekeeper *tk, + s64 error, s64 *interval, s64 *offset) { s64 tick_error, i; @@ -829,7 +829,7 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval, * here. This is tuned so that an error of about 1 msec is adjusted * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks). */ - error2 = timekeeper.ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ); + error2 = tk->ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ); error2 = abs(error2); for (look_ahead = 0; error2 > 0; look_ahead++) error2 >>= 2; @@ -838,8 +838,8 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval, * Now calculate the error in (1 << look_ahead) ticks, but first * remove the single look ahead already included in the error. */ - tick_error = ntp_tick_length() >> (timekeeper.ntp_error_shift + 1); - tick_error -= timekeeper.xtime_interval >> 1; + tick_error = ntp_tick_length() >> (tk->ntp_error_shift + 1); + tick_error -= tk->xtime_interval >> 1; error = ((error - tick_error) >> look_ahead) + tick_error; /* Finally calculate the adjustment shift value. */ @@ -864,9 +864,9 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval, * this is optimized for the most common adjustments of -1,0,1, * for other values we can do a bit more work. */ -static void timekeeping_adjust(s64 offset) +static void timekeeping_adjust(struct timekeeper *tk, s64 offset) { - s64 error, interval = timekeeper.cycle_interval; + s64 error, interval = tk->cycle_interval; int adj; /* @@ -882,7 +882,7 @@ static void timekeeping_adjust(s64 offset) * * Note: It does not "save" on aggravation when reading the code. */ - error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1); + error = tk->ntp_error >> (tk->ntp_error_shift - 1); if (error > interval) { /* * We now divide error by 4(via shift), which checks if @@ -904,7 +904,8 @@ static void timekeeping_adjust(s64 offset) if (likely(error <= interval)) adj = 1; else - adj = timekeeping_bigadjust(error, &interval, &offset); + adj = timekeeping_bigadjust(tk, error, &interval, + &offset); } else if (error < -interval) { /* See comment above, this is just switched for the negative */ error >>= 2; @@ -913,18 +914,17 @@ static void timekeeping_adjust(s64 offset) interval = -interval; offset = -offset; } else - adj = timekeeping_bigadjust(error, &interval, &offset); - } else /* No adjustment needed */ + adj = timekeeping_bigadjust(tk, error, &interval, + &offset); + } else return; - if (unlikely(timekeeper.clock->maxadj && - (timekeeper.mult + adj > - timekeeper.clock->mult + timekeeper.clock->maxadj))) { + if (unlikely(tk->clock->maxadj && + (tk->mult + adj > tk->clock->mult + tk->clock->maxadj))) { printk_once(KERN_WARNING "Adjusting %s more than 11%% (%ld vs %ld)\n", - timekeeper.clock->name, (long)timekeeper.mult + adj, - (long)timekeeper.clock->mult + - timekeeper.clock->maxadj); + tk->clock->name, (long)tk->mult + adj, + (long)tk->clock->mult + tk->clock->maxadj); } /* * So the following can be confusing. @@ -975,11 +975,10 @@ static void timekeeping_adjust(s64 offset) * * XXX - TODO: Doc ntp_error calculation. */ - timekeeper.mult += adj; - timekeeper.xtime_interval += interval; - timekeeper.xtime_nsec -= offset; - timekeeper.ntp_error -= (interval - offset) << - timekeeper.ntp_error_shift; + tk->mult += adj; + tk->xtime_interval += interval; + tk->xtime_nsec -= offset; + tk->ntp_error -= (interval - offset) << tk->ntp_error_shift; /* * It may be possible that when we entered this function, xtime_nsec @@ -995,10 +994,10 @@ static void timekeeping_adjust(s64 offset) * We'll correct this error next time through this function, when * xtime_nsec is not as small. */ - if (unlikely((s64)timekeeper.xtime_nsec < 0)) { - s64 neg = -(s64)timekeeper.xtime_nsec; - timekeeper.xtime_nsec = 0; - timekeeper.ntp_error += neg << timekeeper.ntp_error_shift; + if (unlikely((s64)tk->xtime_nsec < 0)) { + s64 neg = -(s64)tk->xtime_nsec; + tk->xtime_nsec = 0; + tk->ntp_error += neg << tk->ntp_error_shift; } } @@ -1042,37 +1041,36 @@ static inline void accumulate_nsecs_to_secs(struct timekeeper *tk) * * Returns the unconsumed cycles. */ -static cycle_t logarithmic_accumulation(cycle_t offset, u32 shift) +static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, + u32 shift) { u64 raw_nsecs; - /* If the offset is smaller than a shifted interval, do nothing */ - if (offset < timekeeper.cycle_interval<<shift) + /* If the offset is smaller then a shifted interval, do nothing */ + if (offset < tk->cycle_interval<<shift) return offset; /* Accumulate one shifted interval */ - offset -= timekeeper.cycle_interval << shift; - timekeeper.clock->cycle_last += timekeeper.cycle_interval << shift; + offset -= tk->cycle_interval << shift; + tk->clock->cycle_last += tk->cycle_interval << shift; - timekeeper.xtime_nsec += timekeeper.xtime_interval << shift; - - accumulate_nsecs_to_secs(&timekeeper); + tk->xtime_nsec += tk->xtime_interval << shift; + accumulate_nsecs_to_secs(tk); /* Accumulate raw time */ - raw_nsecs = timekeeper.raw_interval << shift; - raw_nsecs += timekeeper.raw_time.tv_nsec; + raw_nsecs = tk->raw_interval << shift; + raw_nsecs += tk->raw_time.tv_nsec; if (raw_nsecs >= NSEC_PER_SEC) { u64 raw_secs = raw_nsecs; raw_nsecs = do_div(raw_secs, NSEC_PER_SEC); - timekeeper.raw_time.tv_sec += raw_secs; + tk->raw_time.tv_sec += raw_secs; } - timekeeper.raw_time.tv_nsec = raw_nsecs; + tk->raw_time.tv_nsec = raw_nsecs; /* Accumulate error between NTP and clock interval */ - timekeeper.ntp_error += ntp_tick_length() << shift; - timekeeper.ntp_error -= - (timekeeper.xtime_interval + timekeeper.xtime_remainder) << - (timekeeper.ntp_error_shift + shift); + tk->ntp_error += ntp_tick_length() << shift; + tk->ntp_error -= (tk->xtime_interval + tk->xtime_remainder) << + (tk->ntp_error_shift + shift); return offset; } @@ -1118,13 +1116,13 @@ static void update_wall_time(void) maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1; shift = min(shift, maxshift); while (offset >= timekeeper.cycle_interval) { - offset = logarithmic_accumulation(offset, shift); + offset = logarithmic_accumulation(&timekeeper, offset, shift); if(offset < timekeeper.cycle_interval<<shift) shift--; } /* correct the clock when NTP error is too big */ - timekeeping_adjust(offset); + timekeeping_adjust(&timekeeper, offset); /* @@ -1147,7 +1145,7 @@ static void update_wall_time(void) */ accumulate_nsecs_to_secs(&timekeeper); - timekeeping_update(false); + timekeeping_update(&timekeeper, false); out: write_sequnlock_irqrestore(&timekeeper.lock, flags); @@ -1198,7 +1196,7 @@ void get_monotonic_boottime(struct timespec *ts) do { seq = read_seqbegin(&timekeeper.lock); ts->tv_sec = timekeeper.xtime_sec; - ts->tv_nsec = timekeeping_get_ns(); + ts->tv_nsec = timekeeping_get_ns(&timekeeper); tomono = timekeeper.wall_to_monotonic; sleep = timekeeper.total_sleep_time; @@ -1330,7 +1328,7 @@ ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot) seq = read_seqbegin(&timekeeper.lock); secs = timekeeper.xtime_sec; - nsecs = timekeeping_get_ns(); + nsecs = timekeeping_get_ns(&timekeeper); *offs_real = timekeeper.offs_real; *offs_boot = timekeeper.offs_boot; |