*/
/*
*/
+/*-
+ * Copyright (c) 1982, 1986, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)time.h 8.5 (Berkeley) 5/4/95
+ * $FreeBSD$
+ */
#include <mach/mach_types.h>
#include <kern/thread.h>
#include <kern/clock.h>
#include <kern/host_notify.h>
+#include <kern/thread_call.h>
+#include <libkern/OSAtomic.h>
#include <IOKit/IOPlatformExpert.h>
#include <machine/commpage.h>
+#include <machine/config.h>
+#include <machine/machine_routines.h>
#include <mach/mach_traps.h>
#include <mach/mach_time.h>
#include <sys/kdebug.h>
+#include <sys/timex.h>
+#include <kern/arithmetic_128.h>
+#include <os/log.h>
uint32_t hz_tick_interval = 1;
-
+static uint64_t has_monotonic_clock = 0;
decl_simple_lock_data(,clock_lock)
+lck_grp_attr_t * settime_lock_grp_attr;
+lck_grp_t * settime_lock_grp;
+lck_attr_t * settime_lock_attr;
+lck_mtx_t settime_lock;
#define clock_lock() \
simple_lock(&clock_lock)
#define clock_lock_init() \
simple_lock_init(&clock_lock, 0)
+#ifdef kdp_simple_lock_is_acquired
+boolean_t kdp_clock_is_locked()
+{
+ return kdp_simple_lock_is_acquired(&clock_lock);
+}
+#endif
+
+struct bintime {
+ time_t sec;
+ uint64_t frac;
+};
+
+static __inline void
+bintime_addx(struct bintime *_bt, uint64_t _x)
+{
+ uint64_t _u;
+
+ _u = _bt->frac;
+ _bt->frac += _x;
+ if (_u > _bt->frac)
+ _bt->sec++;
+}
+
+static __inline void
+bintime_subx(struct bintime *_bt, uint64_t _x)
+{
+ uint64_t _u;
+
+ _u = _bt->frac;
+ _bt->frac -= _x;
+ if (_u < _bt->frac)
+ _bt->sec--;
+}
+
+static __inline void
+bintime_addns(struct bintime *bt, uint64_t ns)
+{
+ bt->sec += ns/ (uint64_t)NSEC_PER_SEC;
+ ns = ns % (uint64_t)NSEC_PER_SEC;
+ if (ns) {
+ /* 18446744073 = int(2^64 / NSEC_PER_SEC) */
+ ns = ns * (uint64_t)18446744073LL;
+ bintime_addx(bt, ns);
+ }
+}
+
+static __inline void
+bintime_subns(struct bintime *bt, uint64_t ns)
+{
+ bt->sec -= ns/ (uint64_t)NSEC_PER_SEC;
+ ns = ns % (uint64_t)NSEC_PER_SEC;
+ if (ns) {
+ /* 18446744073 = int(2^64 / NSEC_PER_SEC) */
+ ns = ns * (uint64_t)18446744073LL;
+ bintime_subx(bt, ns);
+ }
+}
+
+static __inline void
+bintime_addxns(struct bintime *bt, uint64_t a, int64_t xns)
+{
+ uint64_t uxns = (xns > 0)?(uint64_t )xns:(uint64_t)-xns;
+ uint64_t ns = multi_overflow(a, uxns);
+ if (xns > 0) {
+ if (ns)
+ bintime_addns(bt, ns);
+ ns = (a * uxns) / (uint64_t)NSEC_PER_SEC;
+ bintime_addx(bt, ns);
+ }
+ else{
+ if (ns)
+ bintime_subns(bt, ns);
+ ns = (a * uxns) / (uint64_t)NSEC_PER_SEC;
+ bintime_subx(bt,ns);
+ }
+}
+
+
+static __inline void
+bintime_add(struct bintime *_bt, const struct bintime *_bt2)
+{
+ uint64_t _u;
+
+ _u = _bt->frac;
+ _bt->frac += _bt2->frac;
+ if (_u > _bt->frac)
+ _bt->sec++;
+ _bt->sec += _bt2->sec;
+}
+
+static __inline void
+bintime_sub(struct bintime *_bt, const struct bintime *_bt2)
+{
+ uint64_t _u;
+
+ _u = _bt->frac;
+ _bt->frac -= _bt2->frac;
+ if (_u < _bt->frac)
+ _bt->sec--;
+ _bt->sec -= _bt2->sec;
+}
+
+static __inline void
+clock2bintime(const clock_sec_t *secs, const clock_usec_t *microsecs, struct bintime *_bt)
+{
+
+ _bt->sec = *secs;
+ /* 18446744073709 = int(2^64 / 1000000) */
+ _bt->frac = *microsecs * (uint64_t)18446744073709LL;
+}
+
+static __inline void
+bintime2usclock(const struct bintime *_bt, clock_sec_t *secs, clock_usec_t *microsecs)
+{
+
+ *secs = _bt->sec;
+ *microsecs = ((uint64_t)USEC_PER_SEC * (uint32_t)(_bt->frac >> 32)) >> 32;
+}
+
+static __inline void
+bintime2nsclock(const struct bintime *_bt, clock_sec_t *secs, clock_usec_t *nanosecs)
+{
+
+ *secs = _bt->sec;
+ *nanosecs = ((uint64_t)NSEC_PER_SEC * (uint32_t)(_bt->frac >> 32)) >> 32;
+}
+
+static __inline void
+bintime2absolutetime(const struct bintime *_bt, uint64_t *abs)
+{
+ uint64_t nsec;
+ nsec = (uint64_t) _bt->sec * (uint64_t)NSEC_PER_SEC + (((uint64_t)NSEC_PER_SEC * (uint32_t)(_bt->frac >> 32)) >> 32);
+ nanoseconds_to_absolutetime(nsec, abs);
+}
+
+struct latched_time {
+ uint64_t monotonic_time_usec;
+ uint64_t mach_time;
+};
+
+extern int
+kernel_sysctlbyname(const char *name, void *oldp, size_t *oldlenp, void *newp, size_t newlen);
/*
* Time of day (calendar) variables.
*
* Algorithm:
*
- * TOD <- (seconds + epoch, fraction) <- CONV(current absolute time + offset)
+ * TOD <- bintime + delta*scale
*
- * where CONV converts absolute time units into seconds and a fraction.
+ * where :
+ * bintime is a cumulative offset that includes bootime and scaled time elapsed betweed bootime and last scale update.
+ * delta is ticks elapsed since last scale update.
+ * scale is computed according to an adjustment provided by ntp_kern.
*/
static struct clock_calend {
- uint64_t epoch;
- uint64_t offset;
- uint64_t epoch_absolute;
-
- int32_t adjdelta; /* Nanosecond time delta for this adjustment period */
- uint64_t adjstart; /* Absolute time value for start of this adjustment period */
- uint32_t adjoffset; /* Absolute time offset for this adjustment period as absolute value */
+ uint64_t s_scale_ns; /* scale to apply for each second elapsed, it converts in ns */
+ int64_t s_adj_nsx; /* additional adj to apply for each second elapsed, it is expressed in 64 bit frac of ns */
+ uint64_t tick_scale_x; /* scale to apply for each tick elapsed, it converts in 64 bit frac of s */
+ uint64_t offset_count; /* abs time from which apply current scales */
+ struct bintime offset; /* cumulative offset expressed in (sec, 64 bits frac of a second) */
+ struct bintime bintime; /* cumulative offset (it includes bootime) expressed in (sec, 64 bits frac of a second) */
+ struct bintime boottime; /* boot time expressed in (sec, 64 bits frac of a second) */
+ struct bintime basesleep;
} clock_calend;
+static uint64_t ticks_per_sec; /* ticks in a second (expressed in abs time) */
+
+#if DEVELOPMENT || DEBUG
+clock_sec_t last_utc_sec = 0;
+clock_usec_t last_utc_usec = 0;
+clock_sec_t max_utc_sec = 0;
+clock_sec_t last_sys_sec = 0;
+clock_usec_t last_sys_usec = 0;
+#endif
+
+#if DEVELOPMENT || DEBUG
+extern int g_should_log_clock_adjustments;
+
+static void print_all_clock_variables(const char*, clock_sec_t* pmu_secs, clock_usec_t* pmu_usec, clock_sec_t* sys_secs, clock_usec_t* sys_usec, struct clock_calend* calend_cp);
+static void print_all_clock_variables_internal(const char *, struct clock_calend* calend_cp);
+#else
+#define print_all_clock_variables(...) do { } while (0)
+#define print_all_clock_variables_internal(...) do { } while (0)
+#endif
+
#if CONFIG_DTRACE
+
/*
* Unlocked calendar flipflop; this is used to track a clock_calend such
* that we can safely access a snapshot of a valid clock_calend structure
#endif
-/*
- * Calendar adjustment variables and values.
- */
-#define calend_adjperiod (NSEC_PER_SEC / 100) /* adjustment period, ns */
-#define calend_adjskew (40 * NSEC_PER_USEC) /* "standard" skew, ns / period */
-#define calend_adjbig (NSEC_PER_SEC) /* use 10x skew above adjbig ns */
-
-static int64_t calend_adjtotal; /* Nanosecond remaining total adjustment */
-static uint64_t calend_adjdeadline; /* Absolute time value for next adjustment period */
-static uint32_t calend_adjinterval; /* Absolute time interval of adjustment period */
-
-static timer_call_data_t calend_adjcall;
-static uint32_t calend_adjactive;
-
-static uint32_t calend_set_adjustment(
- long *secs,
- int *microsecs);
+void _clock_delay_until_deadline(uint64_t interval, uint64_t deadline);
+void _clock_delay_until_deadline_with_leeway(uint64_t interval, uint64_t deadline, uint64_t leeway);
-static void calend_adjust_call(void);
-static uint32_t calend_adjust(void);
-
-void _clock_delay_until_deadline(uint64_t interval,
- uint64_t deadline);
-void _clock_delay_until_deadline_with_leeway(uint64_t interval,
- uint64_t deadline,
- uint64_t leeway);
-
-static uint64_t clock_boottime; /* Seconds boottime epoch */
+/* Boottime variables*/
+static uint64_t clock_boottime;
+static uint32_t clock_boottime_usec;
#define TIME_ADD(rsecs, secs, rfrac, frac, unit) \
MACRO_BEGIN \
void
clock_config(void)
{
+
clock_lock_init();
- timer_call_setup(&calend_adjcall, (timer_call_func_t)calend_adjust_call, NULL);
+ settime_lock_grp_attr = lck_grp_attr_alloc_init();
+ settime_lock_grp = lck_grp_alloc_init("settime grp", settime_lock_grp_attr);
+ settime_lock_attr = lck_attr_alloc_init();
+ lck_mtx_init(&settime_lock, settime_lock_grp, settime_lock_attr);
clock_oldconfig();
+
+ ntp_init();
+
+ nanoseconds_to_absolutetime((uint64_t)NSEC_PER_SEC, &ticks_per_sec);
}
/*
{
uint64_t abstime;
- nanoseconds_to_absolutetime(calend_adjperiod, &abstime);
- calend_adjinterval = (uint32_t)abstime;
-
nanoseconds_to_absolutetime(NSEC_PER_SEC / 100, &abstime);
hz_tick_interval = (uint32_t)abstime;
struct mach_timebase_info_trap_args *args)
{
mach_vm_address_t out_info_addr = args->info;
- mach_timebase_info_data_t info;
+ mach_timebase_info_data_t info = {};
clock_timebase_info(&info);
*/
void
clock_get_calendar_microtime(
- clock_sec_t *secs,
+ clock_sec_t *secs,
clock_usec_t *microsecs)
{
clock_get_calendar_absolute_and_microtime(secs, microsecs, NULL);
}
+/*
+ * get_scale_factors_from_adj:
+ *
+ * computes scale factors from the value given in adjustment.
+ *
+ * Part of the code has been taken from tc_windup of FreeBSD
+ * written by Poul-Henning Kamp <phk@FreeBSD.ORG>, Julien Ridoux and
+ * Konstantin Belousov.
+ * https://github.com/freebsd/freebsd/blob/master/sys/kern/kern_tc.c
+ */
+static void
+get_scale_factors_from_adj(int64_t adjustment, uint64_t* tick_scale_x, uint64_t* s_scale_ns, int64_t* s_adj_nsx)
+{
+ uint64_t scale;
+ int64_t nano, frac;
+
+ /*-
+ * Calculating the scaling factor. We want the number of 1/2^64
+ * fractions of a second per period of the hardware counter, taking
+ * into account the th_adjustment factor which the NTP PLL/adjtime(2)
+ * processing provides us with.
+ *
+ * The th_adjustment is nanoseconds per second with 32 bit binary
+ * fraction and we want 64 bit binary fraction of second:
+ *
+ * x = a * 2^32 / 10^9 = a * 4.294967296
+ *
+ * The range of th_adjustment is +/- 5000PPM so inside a 64bit int
+ * we can only multiply by about 850 without overflowing, that
+ * leaves no suitably precise fractions for multiply before divide.
+ *
+ * Divide before multiply with a fraction of 2199/512 results in a
+ * systematic undercompensation of 10PPM of th_adjustment. On a
+ * 5000PPM adjustment this is a 0.05PPM error. This is acceptable.
+ *
+ * We happily sacrifice the lowest of the 64 bits of our result
+ * to the goddess of code clarity.
+ *
+ */
+ scale = (uint64_t)1 << 63;
+ scale += (adjustment / 1024) * 2199;
+ scale /= ticks_per_sec;
+ *tick_scale_x = scale * 2;
+
+ /*
+ * hi part of adj
+ * it contains ns (without fraction) to add to the next sec.
+ * Get ns scale factor for the next sec.
+ */
+ nano = (adjustment > 0)? adjustment >> 32 : -((-adjustment) >> 32);
+ scale = (uint64_t) NSEC_PER_SEC;
+ scale += nano;
+ *s_scale_ns = scale;
+
+ /*
+ * lo part of adj
+ * it contains 32 bit frac of ns to add to the next sec.
+ * Keep it as additional adjustment for the next sec.
+ */
+ frac = (adjustment > 0)? ((uint32_t) adjustment) : -((uint32_t) (-adjustment));
+ *s_adj_nsx = (frac>0)? frac << 32 : -( (-frac) << 32);
+
+ return;
+}
+
+/*
+ * scale_delta:
+ *
+ * returns a bintime struct representing delta scaled accordingly to the
+ * scale factors provided to this function.
+ */
+static struct bintime
+scale_delta(uint64_t delta, uint64_t tick_scale_x, uint64_t s_scale_ns, int64_t s_adj_nsx)
+{
+ uint64_t sec, new_ns, over;
+ struct bintime bt;
+
+ bt.sec = 0;
+ bt.frac = 0;
+
+ /*
+ * If more than one second is elapsed,
+ * scale fully elapsed seconds using scale factors for seconds.
+ * s_scale_ns -> scales sec to ns.
+ * s_adj_nsx -> additional adj expressed in 64 bit frac of ns to apply to each sec.
+ */
+ if (delta > ticks_per_sec) {
+ sec = (delta/ticks_per_sec);
+ new_ns = sec * s_scale_ns;
+ bintime_addns(&bt, new_ns);
+ if (s_adj_nsx) {
+ if (sec == 1) {
+ /* shortcut, no overflow can occur */
+ if (s_adj_nsx > 0)
+ bintime_addx(&bt, (uint64_t)s_adj_nsx/ (uint64_t)NSEC_PER_SEC);
+ else
+ bintime_subx(&bt, (uint64_t)-s_adj_nsx/ (uint64_t)NSEC_PER_SEC);
+ }
+ else{
+ /*
+ * s_adj_nsx is 64 bit frac of ns.
+ * sec*s_adj_nsx might overflow in int64_t.
+ * use bintime_addxns to not lose overflowed ns.
+ */
+ bintime_addxns(&bt, sec, s_adj_nsx);
+ }
+ }
+ delta = (delta % ticks_per_sec);
+ }
+
+ over = multi_overflow(tick_scale_x, delta);
+ if(over){
+ bt.sec += over;
+ }
+
+ /*
+ * scale elapsed ticks using the scale factor for ticks.
+ */
+ bintime_addx(&bt, delta * tick_scale_x);
+
+ return bt;
+}
+
+/*
+ * get_scaled_time:
+ *
+ * returns the scaled time of the time elapsed from the last time
+ * scale factors were updated to now.
+ */
+static struct bintime
+get_scaled_time(uint64_t now)
+{
+ uint64_t delta;
+
+ /*
+ * Compute ticks elapsed since last scale update.
+ * This time will be scaled according to the value given by ntp kern.
+ */
+ delta = now - clock_calend.offset_count;
+
+ return scale_delta(delta, clock_calend.tick_scale_x, clock_calend.s_scale_ns, clock_calend.s_adj_nsx);
+}
+
+static void
+clock_get_calendar_absolute_and_microtime_locked(
+ clock_sec_t *secs,
+ clock_usec_t *microsecs,
+ uint64_t *abstime)
+{
+ uint64_t now;
+ struct bintime bt;
+
+ now = mach_absolute_time();
+ if (abstime)
+ *abstime = now;
+
+ bt = get_scaled_time(now);
+ bintime_add(&bt, &clock_calend.bintime);
+ bintime2usclock(&bt, secs, microsecs);
+}
+
+static void
+clock_get_calendar_absolute_and_nanotime_locked(
+ clock_sec_t *secs,
+ clock_usec_t *nanosecs,
+ uint64_t *abstime)
+{
+ uint64_t now;
+ struct bintime bt;
+
+ now = mach_absolute_time();
+ if (abstime)
+ *abstime = now;
+
+ bt = get_scaled_time(now);
+ bintime_add(&bt, &clock_calend.bintime);
+ bintime2nsclock(&bt, secs, nanosecs);
+}
+
/*
* clock_get_calendar_absolute_and_microtime:
*
*/
void
clock_get_calendar_absolute_and_microtime(
- clock_sec_t *secs,
+ clock_sec_t *secs,
clock_usec_t *microsecs,
uint64_t *abstime)
{
- uint64_t now;
spl_t s;
s = splclock();
clock_lock();
- now = mach_absolute_time();
- if (abstime)
- *abstime = now;
-
- if (clock_calend.adjdelta < 0) {
- uint32_t t32;
-
- /*
- * Since offset is decremented during a negative adjustment,
- * ensure that time increases monotonically without going
- * temporarily backwards.
- * If the delta has not yet passed, now is set to the start
- * of the current adjustment period; otherwise, we're between
- * the expiry of the delta and the next call to calend_adjust(),
- * and we offset accordingly.
- */
- if (now > clock_calend.adjstart) {
- t32 = (uint32_t)(now - clock_calend.adjstart);
-
- if (t32 > clock_calend.adjoffset)
- now -= clock_calend.adjoffset;
- else
- now = clock_calend.adjstart;
- }
- }
-
- now += clock_calend.offset;
-
- absolutetime_to_microtime(now, secs, microsecs);
-
- *secs += (clock_sec_t)clock_calend.epoch;
+ clock_get_calendar_absolute_and_microtime_locked(secs, microsecs, abstime);
clock_unlock();
splx(s);
*/
void
clock_get_calendar_nanotime(
- clock_sec_t *secs,
+ clock_sec_t *secs,
clock_nsec_t *nanosecs)
{
- uint64_t now;
spl_t s;
s = splclock();
clock_lock();
- now = mach_absolute_time();
-
- if (clock_calend.adjdelta < 0) {
- uint32_t t32;
-
- if (now > clock_calend.adjstart) {
- t32 = (uint32_t)(now - clock_calend.adjstart);
-
- if (t32 > clock_calend.adjoffset)
- now -= clock_calend.adjoffset;
- else
- now = clock_calend.adjstart;
- }
- }
-
- now += clock_calend.offset;
-
- absolutetime_to_microtime(now, secs, nanosecs);
-
- *nanosecs *= NSEC_PER_USEC;
-
- *secs += (clock_sec_t)clock_calend.epoch;
+ clock_get_calendar_absolute_and_nanotime_locked(secs, nanosecs, NULL);
clock_unlock();
splx(s);
*/
void
clock_gettimeofday(
- clock_sec_t *secs,
+ clock_sec_t *secs,
clock_usec_t *microsecs)
+{
+ clock_gettimeofday_and_absolute_time(secs, microsecs, NULL);
+}
+
+void
+clock_gettimeofday_and_absolute_time(
+ clock_sec_t *secs,
+ clock_usec_t *microsecs,
+ uint64_t *mach_time)
{
uint64_t now;
spl_t s;
+ struct bintime bt;
s = splclock();
clock_lock();
now = mach_absolute_time();
+ bt = get_scaled_time(now);
+ bintime_add(&bt, &clock_calend.bintime);
+ bintime2usclock(&bt, secs, microsecs);
- if (clock_calend.adjdelta >= 0) {
- clock_gettimeofday_set_commpage(now, clock_calend.epoch, clock_calend.offset, secs, microsecs);
- }
- else {
- uint32_t t32;
+ clock_gettimeofday_set_commpage(now, bt.sec, bt.frac, clock_calend.tick_scale_x, ticks_per_sec);
- if (now > clock_calend.adjstart) {
- t32 = (uint32_t)(now - clock_calend.adjstart);
-
- if (t32 > clock_calend.adjoffset)
- now -= clock_calend.adjoffset;
- else
- now = clock_calend.adjstart;
- }
-
- now += clock_calend.offset;
-
- absolutetime_to_microtime(now, secs, microsecs);
+ clock_unlock();
+ splx(s);
- *secs += (clock_sec_t)clock_calend.epoch;
+ if (mach_time) {
+ *mach_time = now;
}
+}
- clock_unlock();
- splx(s);
+static void
+update_basesleep(struct bintime delta, bool forward)
+{
+ /*
+ * Update basesleep only if the platform does not have monotonic clock.
+ * In that case the sleep time computation will use the PMU time
+ * which offset gets modified by settimeofday.
+ * We don't need this for mononic clock because in that case the sleep
+ * time computation is independent from the offset value of the PMU.
+ */
+ if (!has_monotonic_clock) {
+ if (forward)
+ bintime_add(&clock_calend.basesleep, &delta);
+ else
+ bintime_sub(&clock_calend.basesleep, &delta);
+ }
}
/*
*/
void
clock_set_calendar_microtime(
- clock_sec_t secs,
+ clock_sec_t secs,
clock_usec_t microsecs)
{
- clock_sec_t sys;
- clock_usec_t microsys;
- clock_sec_t newsecs;
- clock_usec_t newmicrosecs;
- spl_t s;
+ uint64_t absolutesys;
+ clock_sec_t newsecs;
+ clock_sec_t oldsecs;
+ clock_usec_t newmicrosecs;
+ clock_usec_t oldmicrosecs;
+ uint64_t commpage_value;
+ spl_t s;
+ struct bintime bt;
+ clock_sec_t deltasecs;
+ clock_usec_t deltamicrosecs;
+
+ newsecs = secs;
+ newmicrosecs = microsecs;
- newsecs = secs;
- newmicrosecs = microsecs;
+ /*
+ * settime_lock mtx is used to avoid that racing settimeofdays update the wall clock and
+ * the platform clock concurrently.
+ *
+ * clock_lock cannot be used for this race because it is acquired from interrupt context
+ * and it needs interrupts disabled while instead updating the platform clock needs to be
+ * called with interrupts enabled.
+ */
+ lck_mtx_lock(&settime_lock);
s = splclock();
clock_lock();
+#if DEVELOPMENT || DEBUG
+ struct clock_calend clock_calend_cp = clock_calend;
+#endif
commpage_disable_timestamp();
- /*
- * Calculate the new calendar epoch based on
- * the new value and the system clock.
- */
- clock_get_system_microtime(&sys, µsys);
- TIME_SUB(secs, sys, microsecs, microsys, USEC_PER_SEC);
-
/*
* Adjust the boottime based on the delta.
*/
- clock_boottime += secs - clock_calend.epoch;
+ clock_get_calendar_absolute_and_microtime_locked(&oldsecs, &oldmicrosecs, &absolutesys);
+
+#if DEVELOPMENT || DEBUG
+ if (g_should_log_clock_adjustments) {
+ os_log(OS_LOG_DEFAULT, "%s wall %lu s %d u computed with %llu abs\n",
+ __func__, (unsigned long)oldsecs, oldmicrosecs, absolutesys);
+ os_log(OS_LOG_DEFAULT, "%s requested %lu s %d u\n",
+ __func__, (unsigned long)secs, microsecs );
+ }
+#endif
- /*
- * Set the new calendar epoch.
- */
- clock_calend.epoch = secs;
+ if (oldsecs < secs || (oldsecs == secs && oldmicrosecs < microsecs)) {
+ // moving forwards
+ deltasecs = secs;
+ deltamicrosecs = microsecs;
- nanoseconds_to_absolutetime((uint64_t)microsecs * NSEC_PER_USEC, &clock_calend.offset);
+ TIME_SUB(deltasecs, oldsecs, deltamicrosecs, oldmicrosecs, USEC_PER_SEC);
- clock_interval_to_absolutetime_interval((uint32_t) secs, NSEC_PER_SEC, &clock_calend.epoch_absolute);
- clock_calend.epoch_absolute += clock_calend.offset;
+#if DEVELOPMENT || DEBUG
+ if (g_should_log_clock_adjustments) {
+ os_log(OS_LOG_DEFAULT, "%s delta requested %lu s %d u\n",
+ __func__, (unsigned long)deltasecs, deltamicrosecs);
+ }
+#endif
- /*
- * Cancel any adjustment in progress.
- */
- calend_adjtotal = clock_calend.adjdelta = 0;
+ TIME_ADD(clock_boottime, deltasecs, clock_boottime_usec, deltamicrosecs, USEC_PER_SEC);
+ clock2bintime(&deltasecs, &deltamicrosecs, &bt);
+ bintime_add(&clock_calend.boottime, &bt);
+ update_basesleep(bt, TRUE);
+ } else {
+ // moving backwards
+ deltasecs = oldsecs;
+ deltamicrosecs = oldmicrosecs;
+
+ TIME_SUB(deltasecs, secs, deltamicrosecs, microsecs, USEC_PER_SEC);
+#if DEVELOPMENT || DEBUG
+ if (g_should_log_clock_adjustments) {
+ os_log(OS_LOG_DEFAULT, "%s negative delta requested %lu s %d u\n",
+ __func__, (unsigned long)deltasecs, deltamicrosecs);
+ }
+#endif
+
+ TIME_SUB(clock_boottime, deltasecs, clock_boottime_usec, deltamicrosecs, USEC_PER_SEC);
+ clock2bintime(&deltasecs, &deltamicrosecs, &bt);
+ bintime_sub(&clock_calend.boottime, &bt);
+ update_basesleep(bt, FALSE);
+ }
+
+ clock_calend.bintime = clock_calend.boottime;
+ bintime_add(&clock_calend.bintime, &clock_calend.offset);
+
+ clock2bintime((clock_sec_t *) &secs, (clock_usec_t *) µsecs, &bt);
+
+ clock_gettimeofday_set_commpage(absolutesys, bt.sec, bt.frac, clock_calend.tick_scale_x, ticks_per_sec);
+
+#if DEVELOPMENT || DEBUG
+ struct clock_calend clock_calend_cp1 = clock_calend;
+#endif
+
+ commpage_value = clock_boottime * USEC_PER_SEC + clock_boottime_usec;
clock_unlock();
+ splx(s);
/*
* Set the new value for the platform clock.
+ * This call might block, so interrupts must be enabled.
*/
+#if DEVELOPMENT || DEBUG
+ uint64_t now_b = mach_absolute_time();
+#endif
+
PESetUTCTimeOfDay(newsecs, newmicrosecs);
- splx(s);
+#if DEVELOPMENT || DEBUG
+ uint64_t now_a = mach_absolute_time();
+ if (g_should_log_clock_adjustments) {
+ os_log(OS_LOG_DEFAULT, "%s mach bef PESet %llu mach aft %llu \n", __func__, now_b, now_a);
+ }
+#endif
+
+ print_all_clock_variables_internal(__func__, &clock_calend_cp);
+ print_all_clock_variables_internal(__func__, &clock_calend_cp1);
+
+ commpage_update_boottime(commpage_value);
/*
* Send host notifications.
*/
host_notify_calendar_change();
-
+ host_notify_calendar_set();
+
#if CONFIG_DTRACE
clock_track_calend_nowait();
#endif
+
+ lck_mtx_unlock(&settime_lock);
}
+uint64_t mach_absolutetime_asleep = 0;
+uint64_t mach_absolutetime_last_sleep = 0;
+
+void
+clock_get_calendar_uptime(clock_sec_t *secs)
+{
+ uint64_t now;
+ spl_t s;
+ struct bintime bt;
+
+ s = splclock();
+ clock_lock();
+
+ now = mach_absolute_time();
+
+ bt = get_scaled_time(now);
+ bintime_add(&bt, &clock_calend.offset);
+
+ *secs = bt.sec;
+
+ clock_unlock();
+ splx(s);
+}
+
+
/*
- * clock_initialize_calendar:
+ * clock_update_calendar:
*
- * Set the calendar and related clocks
- * from the platform clock at boot or
- * wake event.
- *
- * Also sends host notifications.
+ * called by ntp timer to update scale factors.
*/
-
-uint64_t mach_absolutetime_asleep;
-uint64_t mach_absolutetime_last_sleep;
-
void
-clock_initialize_calendar(void)
+clock_update_calendar(void)
{
- clock_sec_t sys, secs;
- clock_usec_t microsys, microsecs;
- uint64_t new_epoch;
- spl_t s;
- PEGetUTCTimeOfDay(&secs, µsecs);
+ uint64_t now, delta;
+ struct bintime bt;
+ spl_t s;
+ int64_t adjustment;
s = splclock();
clock_lock();
- commpage_disable_timestamp();
-
- if ((long)secs >= (long)clock_boottime) {
- /*
- * Initialize the boot time based on the platform clock.
- */
- if (clock_boottime == 0)
- clock_boottime = secs;
+ now = mach_absolute_time();
- /*
- * Calculate the new calendar epoch based on
- * the platform clock and the system clock.
- */
- clock_get_system_microtime(&sys, µsys);
- TIME_SUB(secs, sys, microsecs, microsys, USEC_PER_SEC);
+ /*
+ * scale the time elapsed since the last update and
+ * add it to offset.
+ */
+ bt = get_scaled_time(now);
+ bintime_add(&clock_calend.offset, &bt);
- /*
- * Set the new calendar epoch.
- */
+ /*
+ * update the base from which apply next scale factors.
+ */
+ delta = now - clock_calend.offset_count;
+ clock_calend.offset_count += delta;
- clock_calend.epoch = secs;
+ clock_calend.bintime = clock_calend.offset;
+ bintime_add(&clock_calend.bintime, &clock_calend.boottime);
- nanoseconds_to_absolutetime((uint64_t)microsecs * NSEC_PER_USEC, &clock_calend.offset);
+ /*
+ * recompute next adjustment.
+ */
+ ntp_update_second(&adjustment, clock_calend.bintime.sec);
- clock_interval_to_absolutetime_interval((uint32_t) secs, NSEC_PER_SEC, &new_epoch);
- new_epoch += clock_calend.offset;
+#if DEVELOPMENT || DEBUG
+ if (g_should_log_clock_adjustments) {
+ os_log(OS_LOG_DEFAULT, "%s adjustment %lld\n", __func__, adjustment);
+ }
+#endif
+
+ /*
+ * recomputing scale factors.
+ */
+ get_scale_factors_from_adj(adjustment, &clock_calend.tick_scale_x, &clock_calend.s_scale_ns, &clock_calend.s_adj_nsx);
- if (clock_calend.epoch_absolute)
- {
- mach_absolutetime_last_sleep = new_epoch - clock_calend.epoch_absolute;
- mach_absolutetime_asleep += mach_absolutetime_last_sleep;
- KERNEL_DEBUG_CONSTANT(
- MACHDBG_CODE(DBG_MACH_CLOCK,MACH_EPOCH_CHANGE) | DBG_FUNC_NONE,
- (uintptr_t) mach_absolutetime_last_sleep,
- (uintptr_t) mach_absolutetime_asleep,
- (uintptr_t) (mach_absolutetime_last_sleep >> 32),
- (uintptr_t) (mach_absolutetime_asleep >> 32),
- 0);
- }
- clock_calend.epoch_absolute = new_epoch;
+ clock_gettimeofday_set_commpage(now, clock_calend.bintime.sec, clock_calend.bintime.frac, clock_calend.tick_scale_x, ticks_per_sec);
- /*
- * Cancel any adjustment in progress.
- */
- calend_adjtotal = clock_calend.adjdelta = 0;
- }
+#if DEVELOPMENT || DEBUG
+ struct clock_calend calend_cp = clock_calend;
+#endif
clock_unlock();
splx(s);
- /*
- * Send host notifications.
- */
- host_notify_calendar_change();
+ print_all_clock_variables(__func__, NULL,NULL,NULL,NULL, &calend_cp);
+}
+
+
+#if DEVELOPMENT || DEBUG
+
+void print_all_clock_variables_internal(const char* func, struct clock_calend* clock_calend_cp)
+{
+ clock_sec_t offset_secs;
+ clock_usec_t offset_microsecs;
+ clock_sec_t bintime_secs;
+ clock_usec_t bintime_microsecs;
+ clock_sec_t bootime_secs;
+ clock_usec_t bootime_microsecs;
-#if CONFIG_DTRACE
- clock_track_calend_nowait();
-#endif
+ if (!g_should_log_clock_adjustments)
+ return;
+
+ bintime2usclock(&clock_calend_cp->offset, &offset_secs, &offset_microsecs);
+ bintime2usclock(&clock_calend_cp->bintime, &bintime_secs, &bintime_microsecs);
+ bintime2usclock(&clock_calend_cp->boottime, &bootime_secs, &bootime_microsecs);
+
+ os_log(OS_LOG_DEFAULT, "%s s_scale_ns %llu s_adj_nsx %lld tick_scale_x %llu offset_count %llu\n",
+ func , clock_calend_cp->s_scale_ns, clock_calend_cp->s_adj_nsx,
+ clock_calend_cp->tick_scale_x, clock_calend_cp->offset_count);
+ os_log(OS_LOG_DEFAULT, "%s offset.sec %ld offset.frac %llu offset_secs %lu offset_microsecs %d\n",
+ func, clock_calend_cp->offset.sec, clock_calend_cp->offset.frac,
+ (unsigned long)offset_secs, offset_microsecs);
+ os_log(OS_LOG_DEFAULT, "%s bintime.sec %ld bintime.frac %llu bintime_secs %lu bintime_microsecs %d\n",
+ func, clock_calend_cp->bintime.sec, clock_calend_cp->bintime.frac,
+ (unsigned long)bintime_secs, bintime_microsecs);
+ os_log(OS_LOG_DEFAULT, "%s bootime.sec %ld bootime.frac %llu bootime_secs %lu bootime_microsecs %d\n",
+ func, clock_calend_cp->boottime.sec, clock_calend_cp->boottime.frac,
+ (unsigned long)bootime_secs, bootime_microsecs);
+
+ clock_sec_t basesleep_secs;
+ clock_usec_t basesleep_microsecs;
+
+ bintime2usclock(&clock_calend_cp->basesleep, &basesleep_secs, &basesleep_microsecs);
+ os_log(OS_LOG_DEFAULT, "%s basesleep.sec %ld basesleep.frac %llu basesleep_secs %lu basesleep_microsecs %d\n",
+ func, clock_calend_cp->basesleep.sec, clock_calend_cp->basesleep.frac,
+ (unsigned long)basesleep_secs, basesleep_microsecs);
+
}
-/*
- * clock_get_boottime_nanotime:
- *
- * Return the boottime, used by sysctl.
- */
-void
-clock_get_boottime_nanotime(
- clock_sec_t *secs,
- clock_nsec_t *nanosecs)
+
+void print_all_clock_variables(const char* func, clock_sec_t* pmu_secs, clock_usec_t* pmu_usec, clock_sec_t* sys_secs, clock_usec_t* sys_usec, struct clock_calend* clock_calend_cp)
{
- spl_t s;
+ if (!g_should_log_clock_adjustments)
+ return;
- s = splclock();
- clock_lock();
+ struct bintime bt;
+ clock_sec_t wall_secs;
+ clock_usec_t wall_microsecs;
+ uint64_t now;
+ uint64_t delta;
- *secs = (clock_sec_t)clock_boottime;
- *nanosecs = 0;
+ if (pmu_secs) {
+ os_log(OS_LOG_DEFAULT, "%s PMU %lu s %d u \n", func, (unsigned long)*pmu_secs, *pmu_usec);
+ }
+ if (sys_secs) {
+ os_log(OS_LOG_DEFAULT, "%s sys %lu s %d u \n", func, (unsigned long)*sys_secs, *sys_usec);
+ }
- clock_unlock();
- splx(s);
+ print_all_clock_variables_internal(func, clock_calend_cp);
+
+ now = mach_absolute_time();
+ delta = now - clock_calend_cp->offset_count;
+
+ bt = scale_delta(delta, clock_calend_cp->tick_scale_x, clock_calend_cp->s_scale_ns, clock_calend_cp->s_adj_nsx);
+ bintime_add(&bt, &clock_calend_cp->bintime);
+ bintime2usclock(&bt, &wall_secs, &wall_microsecs);
+
+ os_log(OS_LOG_DEFAULT, "%s wall %lu s %d u computed with %llu abs\n",
+ func, (unsigned long)wall_secs, wall_microsecs, now);
}
+
+#endif /* DEVELOPMENT || DEBUG */
+
+
/*
- * clock_adjtime:
+ * clock_initialize_calendar:
*
- * Interface to adjtime() syscall.
+ * Set the calendar and related clocks
+ * from the platform clock at boot.
*
- * Calculates adjustment variables and
- * initiates adjustment.
+ * Also sends host notifications.
*/
void
-clock_adjtime(
- long *secs,
- int *microsecs)
+clock_initialize_calendar(void)
{
- uint32_t interval;
- spl_t s;
+ clock_sec_t sys; // sleepless time since boot in seconds
+ clock_sec_t secs; // Current UTC time
+ clock_sec_t utc_offset_secs; // Difference in current UTC time and sleepless time since boot
+ clock_usec_t microsys;
+ clock_usec_t microsecs;
+ clock_usec_t utc_offset_microsecs;
+ spl_t s;
+ struct bintime bt;
+ struct bintime monotonic_bt;
+ struct latched_time monotonic_time;
+ uint64_t monotonic_usec_total;
+ clock_sec_t sys2, monotonic_sec;
+ clock_usec_t microsys2, monotonic_usec;
+ size_t size;
+
+ //Get PMU time with offset and corresponding sys time
+ PEGetUTCTimeOfDay(&secs, µsecs);
+ clock_get_system_microtime(&sys, µsys);
+
+ /*
+ * If the platform has a monotonic clock, use kern.monotonicclock_usecs
+ * to estimate the sleep/wake time, otherwise use the PMU and adjustments
+ * provided through settimeofday to estimate the sleep time.
+ * NOTE: the latter case relies that the kernel is the only component
+ * to set the PMU offset.
+ */
+ size = sizeof(monotonic_time);
+ if (kernel_sysctlbyname("kern.monotonicclock_usecs", &monotonic_time, &size, NULL, 0) != 0) {
+ has_monotonic_clock = 0;
+ os_log(OS_LOG_DEFAULT, "%s system does not have monotonic clock.\n", __func__);
+ } else {
+ has_monotonic_clock = 1;
+ monotonic_usec_total = monotonic_time.monotonic_time_usec;
+ absolutetime_to_microtime(monotonic_time.mach_time, &sys2, µsys2);
+ os_log(OS_LOG_DEFAULT, "%s system has monotonic clock.\n", __func__);
+ }
s = splclock();
clock_lock();
- interval = calend_set_adjustment(secs, microsecs);
- if (interval != 0) {
- calend_adjdeadline = mach_absolute_time() + interval;
- if (!timer_call_enter(&calend_adjcall, calend_adjdeadline, TIMER_CALL_SYS_CRITICAL))
- calend_adjactive++;
- }
- else
- if (timer_call_cancel(&calend_adjcall))
- calend_adjactive--;
-
- clock_unlock();
- splx(s);
-}
+ commpage_disable_timestamp();
-static uint32_t
-calend_set_adjustment(
- long *secs,
- int *microsecs)
-{
- uint64_t now, t64;
- int64_t total, ototal;
- uint32_t interval = 0;
+ utc_offset_secs = secs;
+ utc_offset_microsecs = microsecs;
- /*
- * Compute the total adjustment time in nanoseconds.
- */
- total = ((int64_t)*secs * (int64_t)NSEC_PER_SEC) + (*microsecs * (int64_t)NSEC_PER_USEC);
+#if DEVELOPMENT || DEBUG
+ last_utc_sec = secs;
+ last_utc_usec = microsecs;
+ last_sys_sec = sys;
+ last_sys_usec = microsys;
+ if (secs > max_utc_sec)
+ max_utc_sec = secs;
+#endif
- /*
- * Disable commpage gettimeofday().
+ /*
+ * We normally expect the UTC clock to be always-on and produce
+ * greater readings than the tick counter. There may be corner cases
+ * due to differing clock resolutions (UTC clock is likely lower) and
+ * and errors reading the UTC clock (some implementations return 0
+ * on error) in which that doesn't hold true. Bring the UTC measurements
+ * in-line with the tick counter measurements as a best effort in that case.
*/
- commpage_disable_timestamp();
+ //FIXME if the current time is prior than 1970 secs will be negative
+ if ((sys > secs) || ((sys == secs) && (microsys > microsecs))) {
+ os_log(OS_LOG_DEFAULT, "%s WARNING: PMU offset is less then sys PMU %lu s %d u sys %lu s %d u\n",
+ __func__, (unsigned long) secs, microsecs, (unsigned long)sys, microsys);
+ secs = utc_offset_secs = sys;
+ microsecs = utc_offset_microsecs = microsys;
+ }
- /*
- * Get current absolute time.
- */
- now = mach_absolute_time();
+ // PMU time with offset - sys
+ // This macro stores the subtraction result in utc_offset_secs and utc_offset_microsecs
+ TIME_SUB(utc_offset_secs, sys, utc_offset_microsecs, microsys, USEC_PER_SEC);
- /*
- * Save the old adjustment total for later return.
- */
- ototal = calend_adjtotal;
+ clock2bintime(&utc_offset_secs, &utc_offset_microsecs, &bt);
/*
- * Is a new correction specified?
+ * Initialize the boot time based on the platform clock.
*/
- if (total != 0) {
- /*
- * Set delta to the standard, small, adjustment skew.
- */
- int32_t delta = calend_adjskew;
-
- if (total > 0) {
- /*
- * Positive adjustment. If greater than the preset 'big'
- * threshold, slew at a faster rate, capping if necessary.
- */
- if (total > (int64_t) calend_adjbig)
- delta *= 10;
- if (delta > total)
- delta = (int32_t)total;
-
- /*
- * Convert the delta back from ns to absolute time and store in adjoffset.
- */
- nanoseconds_to_absolutetime((uint64_t)delta, &t64);
- clock_calend.adjoffset = (uint32_t)t64;
- }
- else {
- /*
- * Negative adjustment; therefore, negate the delta. If
- * greater than the preset 'big' threshold, slew at a faster
- * rate, capping if necessary.
- */
- if (total < (int64_t) -calend_adjbig)
- delta *= 10;
- delta = -delta;
- if (delta < total)
- delta = (int32_t)total;
-
- /*
- * Save the current absolute time. Subsequent time operations occuring
- * during this negative correction can make use of this value to ensure
- * that time increases monotonically.
- */
- clock_calend.adjstart = now;
-
- /*
- * Convert the delta back from ns to absolute time and store in adjoffset.
- */
- nanoseconds_to_absolutetime((uint64_t)-delta, &t64);
- clock_calend.adjoffset = (uint32_t)t64;
- }
+ clock_boottime = secs;
+ clock_boottime_usec = microsecs;
+ commpage_update_boottime(clock_boottime * USEC_PER_SEC + clock_boottime_usec);
- /*
- * Store the total adjustment time in ns.
- */
- calend_adjtotal = total;
-
- /*
- * Store the delta for this adjustment period in ns.
- */
- clock_calend.adjdelta = delta;
+ nanoseconds_to_absolutetime((uint64_t)NSEC_PER_SEC, &ticks_per_sec);
+ clock_calend.boottime = bt;
+ clock_calend.bintime = bt;
+ clock_calend.offset.sec = 0;
+ clock_calend.offset.frac = 0;
- /*
- * Set the interval in absolute time for later return.
- */
- interval = calend_adjinterval;
- }
- else {
- /*
- * No change; clear any prior adjustment.
- */
- calend_adjtotal = clock_calend.adjdelta = 0;
- }
+ clock_calend.tick_scale_x = (uint64_t)1 << 63;
+ clock_calend.tick_scale_x /= ticks_per_sec;
+ clock_calend.tick_scale_x *= 2;
- /*
- * If an prior correction was in progress, return the
- * remaining uncorrected time from it.
- */
- if (ototal != 0) {
- *secs = (long)(ototal / (long)NSEC_PER_SEC);
- *microsecs = (int)((ototal % (int)NSEC_PER_SEC) / (int)NSEC_PER_USEC);
+ clock_calend.s_scale_ns = NSEC_PER_SEC;
+ clock_calend.s_adj_nsx = 0;
+
+ if (has_monotonic_clock) {
+
+ monotonic_sec = monotonic_usec_total / (clock_sec_t)USEC_PER_SEC;
+ monotonic_usec = monotonic_usec_total % (clock_usec_t)USEC_PER_SEC;
+
+ // PMU time without offset - sys
+ // This macro stores the subtraction result in monotonic_sec and monotonic_usec
+ TIME_SUB(monotonic_sec, sys2, monotonic_usec, microsys2, USEC_PER_SEC);
+ clock2bintime(&monotonic_sec, &monotonic_usec, &monotonic_bt);
+
+ // set the baseleep as the difference between monotonic clock - sys
+ clock_calend.basesleep = monotonic_bt;
+ } else {
+ // set the baseleep as the difference between PMU clock - sys
+ clock_calend.basesleep = bt;
}
- else
- *secs = *microsecs = 0;
+ commpage_update_mach_continuous_time(mach_absolutetime_asleep);
+#if DEVELOPMENT || DEBUG
+ struct clock_calend clock_calend_cp = clock_calend;
+#endif
+
+ clock_unlock();
+ splx(s);
+
+ print_all_clock_variables(__func__, &secs, µsecs, &sys, µsys, &clock_calend_cp);
+
+ /*
+ * Send host notifications.
+ */
+ host_notify_calendar_change();
+
#if CONFIG_DTRACE
clock_track_calend_nowait();
#endif
-
- return (interval);
}
-static void
-calend_adjust_call(void)
-{
- uint32_t interval;
- spl_t s;
-
- s = splclock();
- clock_lock();
- if (--calend_adjactive == 0) {
- interval = calend_adjust();
- if (interval != 0) {
- clock_deadline_for_periodic_event(interval, mach_absolute_time(), &calend_adjdeadline);
+void
+clock_wakeup_calendar(void)
+{
+ clock_sec_t sys;
+ clock_sec_t secs;
+ clock_usec_t microsys;
+ clock_usec_t microsecs;
+ spl_t s;
+ struct bintime bt, last_sleep_bt;
+ clock_sec_t basesleep_s, last_sleep_sec;
+ clock_usec_t basesleep_us, last_sleep_usec;
+ struct latched_time monotonic_time;
+ uint64_t monotonic_usec_total;
+ size_t size;
+ clock_sec_t secs_copy;
+ clock_usec_t microsecs_copy;
+#if DEVELOPMENT || DEBUG
+ clock_sec_t utc_sec;
+ clock_usec_t utc_usec;
+ PEGetUTCTimeOfDay(&utc_sec, &utc_usec);
+#endif
- if (!timer_call_enter(&calend_adjcall, calend_adjdeadline, TIMER_CALL_SYS_CRITICAL))
- calend_adjactive++;
+ /*
+ * If the platform has the monotonic clock use that to
+ * compute the sleep time. The monotonic clock does not have an offset
+ * that can be modified, so nor kernel or userspace can change the time
+ * of this clock, it can only monotonically increase over time.
+ * During sleep mach_absolute_time does not tick,
+ * so the sleep time is the difference betwen the current monotonic time
+ * less the absolute time and the previous difference stored at wake time.
+ *
+ * basesleep = monotonic - sys ---> computed at last wake
+ * sleep_time = (monotonic - sys) - basesleep
+ *
+ * If the platform does not support monotonic time we use the PMU time
+ * to compute the last sleep.
+ * The PMU time is the monotonic clock + an offset that can be set
+ * by kernel.
+ *
+ * IMPORTANT:
+ * We assume that only the kernel is setting the offset of the PMU and that
+ * it is doing it only througth the settimeofday interface.
+ *
+ * basesleep is the different between the PMU time and the mach_absolute_time
+ * at wake.
+ * During awake time settimeofday can change the PMU offset by a delta,
+ * and basesleep is shifted by the same delta applyed to the PMU. So the sleep
+ * time computation becomes:
+ *
+ * PMU = monotonic + PMU_offset
+ * basesleep = PMU - sys ---> computed at last wake
+ * basesleep += settimeofday_delta
+ * PMU_offset += settimeofday_delta
+ * sleep_time = (PMU - sys) - basesleep
+ */
+ if (has_monotonic_clock) {
+ //Get monotonic time with corresponding sys time
+ size = sizeof(monotonic_time);
+ if (kernel_sysctlbyname("kern.monotonicclock_usecs", &monotonic_time, &size, NULL, 0) != 0) {
+ panic("%s: could not call kern.monotonicclock_usecs", __func__);
}
- }
+ monotonic_usec_total = monotonic_time.monotonic_time_usec;
+ absolutetime_to_microtime(monotonic_time.mach_time, &sys, µsys);
- clock_unlock();
- splx(s);
-}
+ secs = monotonic_usec_total / (clock_sec_t)USEC_PER_SEC;
+ microsecs = monotonic_usec_total % (clock_usec_t)USEC_PER_SEC;
+ } else {
+ //Get PMU time with offset and corresponding sys time
+ PEGetUTCTimeOfDay(&secs, µsecs);
+ clock_get_system_microtime(&sys, µsys);
-static uint32_t
-calend_adjust(void)
-{
- uint64_t now, t64;
- int32_t delta;
- uint32_t interval = 0;
+ }
+ s = splclock();
+ clock_lock();
+
commpage_disable_timestamp();
- now = mach_absolute_time();
+ secs_copy = secs;
+ microsecs_copy = microsecs;
- delta = clock_calend.adjdelta;
+#if DEVELOPMENT || DEBUG
+ struct clock_calend clock_calend_cp1 = clock_calend;
+#endif /* DEVELOPMENT || DEBUG */
- if (delta > 0) {
- clock_calend.offset += clock_calend.adjoffset;
+#if DEVELOPMENT || DEBUG
+ last_utc_sec = secs;
+ last_utc_usec = microsecs;
+ last_sys_sec = sys;
+ last_sys_usec = microsys;
+ if (secs > max_utc_sec)
+ max_utc_sec = secs;
+#endif
+ /*
+ * We normally expect the UTC clock to be always-on and produce
+ * greater readings than the tick counter. There may be corner cases
+ * due to differing clock resolutions (UTC clock is likely lower) and
+ * and errors reading the UTC clock (some implementations return 0
+ * on error) in which that doesn't hold true. Bring the UTC measurements
+ * in-line with the tick counter measurements as a best effort in that case.
+ */
+ //FIXME if the current time is prior than 1970 secs will be negative
+ if ((sys > secs) || ((sys == secs) && (microsys > microsecs))) {
+ os_log(OS_LOG_DEFAULT, "%s WARNING: %s is less then sys %s %lu s %d u sys %lu s %d u\n",
+ __func__, (has_monotonic_clock)?"monotonic":"PMU", (has_monotonic_clock)?"monotonic":"PMU", (unsigned long)secs, microsecs, (unsigned long)sys, microsys);
+ secs = sys;
+ microsecs = microsys;
+ }
- calend_adjtotal -= delta;
- if (delta > calend_adjtotal) {
- clock_calend.adjdelta = delta = (int32_t)calend_adjtotal;
+ // PMU or monotonic - sys
+ // This macro stores the subtraction result in secs and microsecs
+ TIME_SUB(secs, sys, microsecs, microsys, USEC_PER_SEC);
+ clock2bintime(&secs, µsecs, &bt);
- nanoseconds_to_absolutetime((uint64_t)delta, &t64);
- clock_calend.adjoffset = (uint32_t)t64;
- }
+ /*
+ * Safety belt: the UTC clock will likely have a lower resolution than the tick counter.
+ * It's also possible that the device didn't fully transition to the powered-off state on
+ * the most recent sleep, so the tick counter may not have reset or may have only briefly
+ * tured off. In that case it's possible for the difference between the UTC clock and the
+ * tick counter to be less than the previously recorded value in clock.calend.basesleep.
+ * In that case simply record that we slept for 0 ticks.
+ */
+ if ((bt.sec > clock_calend.basesleep.sec) ||
+ ((bt.sec == clock_calend.basesleep.sec) && (bt.frac > clock_calend.basesleep.frac))) {
+
+ //last_sleep is the difference between current PMU or monotonic - abs and last wake PMU or monotonic - abs
+ last_sleep_bt = bt;
+ bintime_sub(&last_sleep_bt, &clock_calend.basesleep);
+
+ //set baseseep to current PMU or monotonic - abs
+ clock_calend.basesleep = bt;
+ bintime2usclock(&last_sleep_bt, &last_sleep_sec, &last_sleep_usec);
+ bintime2absolutetime(&last_sleep_bt, &mach_absolutetime_last_sleep);
+ mach_absolutetime_asleep += mach_absolutetime_last_sleep;
+
+ bintime_add(&clock_calend.offset, &last_sleep_bt);
+ bintime_add(&clock_calend.bintime, &last_sleep_bt);
+
+ } else{
+ mach_absolutetime_last_sleep = 0;
+ last_sleep_sec = last_sleep_usec = 0;
+ bintime2usclock(&clock_calend.basesleep, &basesleep_s, &basesleep_us);
+ os_log(OS_LOG_DEFAULT, "%s WARNING: basesleep (%lu s %d u) > %s-sys (%lu s %d u) \n",
+ __func__, (unsigned long) basesleep_s, basesleep_us, (has_monotonic_clock)?"monotonic":"PMU", (unsigned long) secs_copy, microsecs_copy );
}
- else
- if (delta < 0) {
- clock_calend.offset -= clock_calend.adjoffset;
- calend_adjtotal -= delta;
- if (delta < calend_adjtotal) {
- clock_calend.adjdelta = delta = (int32_t)calend_adjtotal;
+ KERNEL_DEBUG_CONSTANT(
+ MACHDBG_CODE(DBG_MACH_CLOCK,MACH_EPOCH_CHANGE) | DBG_FUNC_NONE,
+ (uintptr_t) mach_absolutetime_last_sleep,
+ (uintptr_t) mach_absolutetime_asleep,
+ (uintptr_t) (mach_absolutetime_last_sleep >> 32),
+ (uintptr_t) (mach_absolutetime_asleep >> 32),
+ 0);
- nanoseconds_to_absolutetime((uint64_t)-delta, &t64);
- clock_calend.adjoffset = (uint32_t)t64;
- }
+ commpage_update_mach_continuous_time(mach_absolutetime_asleep);
+ adjust_cont_time_thread_calls();
- if (clock_calend.adjdelta != 0)
- clock_calend.adjstart = now;
- }
+#if DEVELOPMENT || DEBUG
+ struct clock_calend clock_calend_cp = clock_calend;
+#endif
+
+ clock_unlock();
+ splx(s);
+
+#if DEVELOPMENT || DEBUG
+ if (g_should_log_clock_adjustments) {
+ os_log(OS_LOG_DEFAULT, "PMU was %lu s %d u\n",(unsigned long) utc_sec, utc_usec);
+ os_log(OS_LOG_DEFAULT, "last sleep was %lu s %d u\n",(unsigned long) last_sleep_sec, last_sleep_usec);
+ print_all_clock_variables("clock_wakeup_calendar:BEFORE",
+ &secs_copy, µsecs_copy, &sys, µsys, &clock_calend_cp1);
+ print_all_clock_variables("clock_wakeup_calendar:AFTER", NULL, NULL, NULL, NULL, &clock_calend_cp);
+ }
+#endif /* DEVELOPMENT || DEBUG */
- if (clock_calend.adjdelta != 0)
- interval = calend_adjinterval;
+ host_notify_calendar_change();
#if CONFIG_DTRACE
clock_track_calend_nowait();
#endif
+}
+
- return (interval);
+/*
+ * clock_get_boottime_nanotime:
+ *
+ * Return the boottime, used by sysctl.
+ */
+void
+clock_get_boottime_nanotime(
+ clock_sec_t *secs,
+ clock_nsec_t *nanosecs)
+{
+ spl_t s;
+
+ s = splclock();
+ clock_lock();
+
+ *secs = (clock_sec_t)clock_boottime;
+ *nanosecs = (clock_nsec_t)clock_boottime_usec * NSEC_PER_USEC;
+
+ clock_unlock();
+ splx(s);
+}
+
+/*
+ * clock_get_boottime_nanotime:
+ *
+ * Return the boottime, used by sysctl.
+ */
+void
+clock_get_boottime_microtime(
+ clock_sec_t *secs,
+ clock_usec_t *microsecs)
+{
+ spl_t s;
+
+ s = splclock();
+ clock_lock();
+
+ *secs = (clock_sec_t)clock_boottime;
+ *microsecs = (clock_nsec_t)clock_boottime_usec;
+
+ clock_unlock();
+ splx(s);
}
+
/*
* Wait / delay routines.
*/
*result = mach_absolute_time() + abstime;
}
+void
+clock_continuoustime_interval_to_deadline(
+ uint64_t conttime,
+ uint64_t *result)
+{
+ *result = mach_continuous_time() + conttime;
+}
+
void
clock_get_uptime(
uint64_t *result)
}
}
+uint64_t
+mach_continuous_time(void)
+{
+ while(1) {
+ uint64_t read1 = mach_absolutetime_asleep;
+ uint64_t absolute = mach_absolute_time();
+ OSMemoryBarrier();
+ uint64_t read2 = mach_absolutetime_asleep;
+
+ if(__builtin_expect(read1 == read2, 1)) {
+ return absolute + read1;
+ }
+ }
+}
+
+uint64_t
+mach_continuous_approximate_time(void)
+{
+ while(1) {
+ uint64_t read1 = mach_absolutetime_asleep;
+ uint64_t absolute = mach_approximate_time();
+ OSMemoryBarrier();
+ uint64_t read2 = mach_absolutetime_asleep;
+
+ if(__builtin_expect(read1 == read2, 1)) {
+ return absolute + read1;
+ }
+ }
+}
+
+/*
+ * continuoustime_to_absolutetime
+ * Must be called with interrupts disabled
+ * Returned value is only valid until the next update to
+ * mach_continuous_time
+ */
+uint64_t
+continuoustime_to_absolutetime(uint64_t conttime) {
+ if (conttime <= mach_absolutetime_asleep)
+ return 0;
+ else
+ return conttime - mach_absolutetime_asleep;
+}
+
+/*
+ * absolutetime_to_continuoustime
+ * Must be called with interrupts disabled
+ * Returned value is only valid until the next update to
+ * mach_continuous_time
+ */
+uint64_t
+absolutetime_to_continuoustime(uint64_t abstime) {
+ return abstime + mach_absolutetime_asleep;
+}
+
#if CONFIG_DTRACE
/*
int i = 0;
uint64_t now;
struct unlocked_clock_calend stable;
+ struct bintime bt;
for (;;) {
stable = flipflop[i]; /* take snapshot */
if (flipflop[i].gen == stable.gen)
break;
- /* Switch to the oher element of the flipflop, and try again. */
+ /* Switch to the other element of the flipflop, and try again. */
i ^= 1;
}
now = mach_absolute_time();
- if (stable.calend.adjdelta < 0) {
- uint32_t t32;
-
- if (now > stable.calend.adjstart) {
- t32 = (uint32_t)(now - stable.calend.adjstart);
-
- if (t32 > stable.calend.adjoffset)
- now -= stable.calend.adjoffset;
- else
- now = stable.calend.adjstart;
- }
- }
-
- now += stable.calend.offset;
+ bt = get_scaled_time(now);
- absolutetime_to_microtime(now, secs, nanosecs);
- *nanosecs *= NSEC_PER_USEC;
+ bintime_add(&bt, &clock_calend.bintime);
- *secs += (clock_sec_t)stable.calend.epoch;
+ bintime2nsclock(&bt, secs, nanosecs);
}
static void
projects / apple / xnu.git / blobdiff