/*
- * Copyright (c) 2000-2008 Apple Inc. All rights reserved.
+ * Copyright (c) 2000-2019 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
+ *
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
- *
+ *
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
+ *
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
- *
+ *
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
*/
/*
*/
+/*-
+ * 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>
-uint32_t hz_tick_interval = 1;
+#include <sys/kdebug.h>
+#include <sys/timex.h>
+#include <kern/arithmetic_128.h>
+#include <os/log.h>
+uint32_t hz_tick_interval = 1;
+#if !HAS_CONTINUOUS_HWCLOCK
+static uint64_t has_monotonic_clock = 0;
+#endif
-decl_simple_lock_data(,clock_lock)
+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() \
+ simple_lock(&clock_lock, LCK_GRP_NULL)
-#define clock_unlock() \
+#define clock_unlock() \
simple_unlock(&clock_lock)
-#define clock_lock_init() \
+#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;
+}
+
+#if !defined(HAS_CONTINUOUS_HWCLOCK)
+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);
+#endif
/*
* 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;
-
- 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) */
+#if !HAS_CONTINUOUS_HWCLOCK
+ struct bintime basesleep;
+#endif
} clock_calend;
-#if CONFIG_DTRACE
+static uint64_t ticks_per_sec; /* ticks in a second (expressed in abs time) */
+
+#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
*
* The trick is to use a generation count and set the low bit when it is
* being updated/read; by doing this, we guarantee, through use of the
- * hw_atomic functions, that the generation is incremented when the bit
+ * os_atomic functions, that the generation is incremented when the bit
* is cleared atomically (by using a 1 bit add).
*/
static struct unlocked_clock_calend {
- struct clock_calend calend; /* copy of calendar */
- uint32_t gen; /* generation count */
-} flipflop[ 2];
+ struct clock_calend calend; /* copy of calendar */
+ uint32_t gen; /* generation count */
+} flipflop[2];
static void clock_track_calend_nowait(void);
#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);
-
-static void calend_adjust_call(void);
-static uint32_t calend_adjust(void);
-
-static thread_call_data_t calend_wakecall;
-
-extern void IOKitResetTime(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);
-void _clock_delay_until_deadline(uint64_t interval,
- uint64_t deadline);
+/* Boottime variables*/
+static uint64_t clock_boottime;
+static uint32_t clock_boottime_usec;
-static uint64_t clock_boottime; /* Seconds boottime epoch */
-
-#define TIME_ADD(rsecs, secs, rfrac, frac, unit) \
-MACRO_BEGIN \
- if (((rfrac) += (frac)) >= (unit)) { \
- (rfrac) -= (unit); \
- (rsecs) += 1; \
- } \
- (rsecs) += (secs); \
+#define TIME_ADD(rsecs, secs, rfrac, frac, unit) \
+MACRO_BEGIN \
+ if (((rfrac) += (frac)) >= (unit)) { \
+ (rfrac) -= (unit); \
+ (rsecs) += 1; \
+ } \
+ (rsecs) += (secs); \
MACRO_END
-#define TIME_SUB(rsecs, secs, rfrac, frac, unit) \
-MACRO_BEGIN \
- if ((int)((rfrac) -= (frac)) < 0) { \
- (rfrac) += (unit); \
- (rsecs) -= 1; \
- } \
- (rsecs) -= (secs); \
+#define TIME_SUB(rsecs, secs, rfrac, frac, unit) \
+MACRO_BEGIN \
+ if ((int)((rfrac) -= (frac)) < 0) { \
+ (rfrac) += (unit); \
+ (rsecs) -= 1; \
+ } \
+ (rsecs) -= (secs); \
MACRO_END
/*
{
clock_lock_init();
- timer_call_setup(&calend_adjcall, (timer_call_func_t)calend_adjust_call, NULL);
- thread_call_setup(&calend_wakecall, (thread_call_func_t)IOKitResetTime, 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);
}
/*
void
clock_timebase_init(void)
{
- uint64_t abstime;
-
- nanoseconds_to_absolutetime(calend_adjperiod, &abstime);
- calend_adjinterval = (uint32_t)abstime;
+ uint64_t abstime;
nanoseconds_to_absolutetime(NSEC_PER_SEC / 100, &abstime);
hz_tick_interval = (uint32_t)abstime;
mach_timebase_info_trap(
struct mach_timebase_info_trap_args *args)
{
- mach_vm_address_t out_info_addr = args->info;
- mach_timebase_info_data_t info;
+ mach_vm_address_t out_info_addr = args->info;
+ mach_timebase_info_data_t info = {};
clock_timebase_info(&info);
- copyout((void *)&info, out_info_addr, sizeof (info));
+ copyout((void *)&info, out_info_addr, sizeof(info));
- return (KERN_SUCCESS);
+ return KERN_SUCCESS;
}
/*
*/
void
clock_get_calendar_microtime(
- clock_sec_t *secs,
- clock_usec_t *microsecs)
+ 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_usec_t *microsecs,
- uint64_t *abstime)
+ clock_sec_t *secs,
+ clock_usec_t *microsecs,
+ uint64_t *abstime)
{
- uint64_t now;
- spl_t s;
+ 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_nsec_t *nanosecs)
+ clock_sec_t *secs,
+ clock_nsec_t *nanosecs)
{
- uint64_t now;
- spl_t s;
+ 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_usec_t *microsecs)
+ 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;
+ 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;
-
- 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_gettimeofday_set_commpage(now, bt.sec, bt.frac, clock_calend.tick_scale_x, ticks_per_sec);
clock_unlock();
splx(s);
+
+ if (mach_time) {
+ *mach_time = now;
+ }
}
/*
*/
void
clock_set_calendar_microtime(
- clock_sec_t secs,
- clock_usec_t microsecs)
+ 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);
- /*
- * 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);
+ } else {
+ // moving backwards
+ deltasecs = oldsecs;
+ deltamicrosecs = oldmicrosecs;
+
+ TIME_SUB(deltasecs, secs, deltamicrosecs, microsecs, USEC_PER_SEC);
+
+ TIME_SUB(clock_boottime, deltasecs, clock_boottime_usec, deltamicrosecs, USEC_PER_SEC);
+ clock2bintime(&deltasecs, &deltamicrosecs, &bt);
+ bintime_sub(&clock_calend.boottime, &bt);
+ }
+
+ 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:
- *
- * Set the calendar and related clocks
- * from the platform clock at boot or
- * wake event.
+ * clock_update_calendar:
*
- * Also sends host notifications.
+ * called by ntp timer to update scale factors.
*/
void
-clock_initialize_calendar(void)
+clock_update_calendar(void)
{
- clock_sec_t sys, secs;
- clock_usec_t microsys, microsecs;
- 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();
+ now = mach_absolute_time();
- if ((long)secs >= (long)clock_boottime) {
- /*
- * Initialize the boot time based on the platform clock.
- */
- if (clock_boottime == 0)
- clock_boottime = secs;
+ /*
+ * scale the time elapsed since the last update and
+ * add it to offset.
+ */
+ bt = get_scaled_time(now);
+ bintime_add(&clock_calend.offset, &bt);
- /*
- * 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);
+ /*
+ * update the base from which apply next scale factors.
+ */
+ delta = now - clock_calend.offset_count;
+ clock_calend.offset_count += delta;
- /*
- * Set the new calendar epoch.
- */
- 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);
- /*
- * Cancel any adjustment in progress.
- */
- calend_adjtotal = clock_calend.adjdelta = 0;
+#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);
+
+ clock_gettimeofday_set_commpage(now, clock_calend.bintime.sec, clock_calend.bintime.frac, clock_calend.tick_scale_x, ticks_per_sec);
+
+#if DEVELOPMENT || DEBUG
+ struct clock_calend calend_cp = clock_calend;
+#endif
clock_unlock();
splx(s);
- /*
- * Send host notifications.
- */
- host_notify_calendar_change();
-
-#if CONFIG_DTRACE
- clock_track_calend_nowait();
+ 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 (!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);
+
+#if !HAS_CONTINUOUS_HWCLOCK
+ 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);
#endif
}
-/*
- * clock_get_boottime_nanotime:
- *
- * Return the boottime, used by sysctl.
- */
+
void
-clock_get_boottime_nanotime(
- clock_sec_t *secs,
- clock_nsec_t *nanosecs)
+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;
+#if !HAS_CONTINUOUS_HWCLOCK
+ 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;
- s = splclock();
- clock_lock();
+#endif
+ //Get the UTC time and corresponding sys time
+ PEGetUTCTimeOfDay(&secs, µsecs);
+ clock_get_system_microtime(&sys, µsys);
- 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++;
+#if !HAS_CONTINUOUS_HWCLOCK
+ /*
+ * If the platform has a monotonic clock, use kern.monotonicclock_usecs
+ * to estimate the sleep/wake time, otherwise use the UTC time to estimate
+ * the sleep time.
+ */
+ 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__);
}
- else
- if (timer_call_cancel(&calend_adjcall))
- calend_adjactive--;
-
- clock_unlock();
- splx(s);
-}
-
-static uint32_t
-calend_set_adjustment(
- long *secs,
- int *microsecs)
-{
- uint64_t now, t64;
- int64_t total, ototal;
- uint32_t interval = 0;
+#endif
- /*
- * Compute the total adjustment time in nanoseconds.
- */
- total = ((int64_t)*secs * (int64_t)NSEC_PER_SEC) + (*microsecs * (int64_t)NSEC_PER_USEC);
+ s = splclock();
+ clock_lock();
- /*
- * Disable commpage gettimeofday().
- */
commpage_disable_timestamp();
- /*
- * Get current absolute time.
- */
- now = mach_absolute_time();
+ utc_offset_secs = secs;
+ utc_offset_microsecs = microsecs;
- /*
- * Save the old adjustment total for later return.
+ /*
+ * 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.
*/
- ototal = calend_adjtotal;
+ if ((sys > secs) || ((sys == secs) && (microsys > microsecs))) {
+ os_log(OS_LOG_DEFAULT, "%s WARNING: UTC time is less then sys time, (%lu s %d u) UTC (%lu s %d u) sys\n",
+ __func__, (unsigned long) secs, microsecs, (unsigned long)sys, microsys);
+ secs = utc_offset_secs = sys;
+ microsecs = utc_offset_microsecs = microsys;
+ }
+
+ // UTC - 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);
+ // This function converts utc_offset_secs and utc_offset_microsecs in bintime
+ 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);
+
+ 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;
+
+ clock_calend.tick_scale_x = (uint64_t)1 << 63;
+ clock_calend.tick_scale_x /= ticks_per_sec;
+ clock_calend.tick_scale_x *= 2;
+
+ clock_calend.s_scale_ns = NSEC_PER_SEC;
+ clock_calend.s_adj_nsx = 0;
+
+#if !HAS_CONTINUOUS_HWCLOCK
+ 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;
+
+ // monotonic clock - 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;
+ }
+#endif
+ commpage_update_mach_continuous_time(mach_absolutetime_asleep);
- /*
- * Store the total adjustment time in ns.
- */
- calend_adjtotal = total;
-
- /*
- * Store the delta for this adjustment period in ns.
- */
- clock_calend.adjdelta = delta;
+#if DEVELOPMENT || DEBUG
+ struct clock_calend clock_calend_cp = clock_calend;
+#endif
- /*
- * 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_unlock();
+ splx(s);
- /*
- * If an prior correction was in progress, return the
- * remaining uncorrected time from it.
+ print_all_clock_variables(__func__, &secs, µsecs, &sys, µsys, &clock_calend_cp);
+
+ /*
+ * Send host notifications.
*/
- if (ototal != 0) {
- *secs = (long)(ototal / (long)NSEC_PER_SEC);
- *microsecs = (int)((ototal % (int)NSEC_PER_SEC) / (int)NSEC_PER_USEC);
- }
- else
- *secs = *microsecs = 0;
+ host_notify_calendar_change();
#if CONFIG_DTRACE
clock_track_calend_nowait();
#endif
-
- return (interval);
}
+#if HAS_CONTINUOUS_HWCLOCK
+
static void
-calend_adjust_call(void)
+scale_sleep_time(void)
+{
+ /* Apply the current NTP frequency adjustment to the time slept.
+ * The frequency adjustment remains stable between calls to ntp_adjtime(),
+ * and should thus provide a reasonable approximation of the total adjustment
+ * required for the time slept. */
+ struct bintime sleep_time;
+ uint64_t tick_scale_x, s_scale_ns;
+ int64_t s_adj_nsx;
+ int64_t sleep_adj = ntp_get_freq();
+ if (sleep_adj) {
+ get_scale_factors_from_adj(sleep_adj, &tick_scale_x, &s_scale_ns, &s_adj_nsx);
+ sleep_time = scale_delta(mach_absolutetime_last_sleep, tick_scale_x, s_scale_ns, s_adj_nsx);
+ } else {
+ tick_scale_x = (uint64_t)1 << 63;
+ tick_scale_x /= ticks_per_sec;
+ tick_scale_x *= 2;
+ sleep_time.sec = mach_absolutetime_last_sleep / ticks_per_sec;
+ sleep_time.frac = (mach_absolutetime_last_sleep % ticks_per_sec) * tick_scale_x;
+ }
+ bintime_add(&clock_calend.offset, &sleep_time);
+ bintime_add(&clock_calend.bintime, &sleep_time);
+}
+
+void
+clock_wakeup_calendar(void)
{
- uint32_t interval;
- spl_t s;
+ 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);
+ commpage_disable_timestamp();
- if (!timer_call_enter(&calend_adjcall, calend_adjdeadline, TIMER_CALL_SYS_CRITICAL))
- calend_adjactive++;
- }
- }
+ uint64_t abstime = mach_absolute_time();
+ uint64_t total_sleep_time = ml_get_hwclock() - abstime;
+
+ mach_absolutetime_last_sleep = total_sleep_time - mach_absolutetime_asleep;
+ mach_absolutetime_asleep = total_sleep_time;
+
+ scale_sleep_time();
+
+ 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);
+
+ commpage_update_mach_continuous_time(mach_absolutetime_asleep);
+ adjust_cont_time_thread_calls();
clock_unlock();
splx(s);
+
+ host_notify_calendar_change();
+
+#if CONFIG_DTRACE
+ clock_track_calend_nowait();
+#endif
}
-static uint32_t
-calend_adjust(void)
+#else /* HAS_CONTINUOUS_HWCLOCK */
+
+void
+clock_wakeup_calendar(void)
{
- uint64_t now, t64;
- int32_t delta;
- uint32_t interval = 0;
+ clock_sec_t wake_sys_sec;
+ clock_usec_t wake_sys_usec;
+ clock_sec_t wake_sec;
+ clock_usec_t wake_usec;
+ clock_sec_t wall_time_sec;
+ clock_usec_t wall_time_usec;
+ clock_sec_t diff_sec;
+ clock_usec_t diff_usec;
+ clock_sec_t var_s;
+ clock_usec_t var_us;
+ spl_t s;
+ struct bintime bt, last_sleep_bt;
+ struct latched_time monotonic_time;
+ uint64_t monotonic_usec_total;
+ uint64_t wake_abs;
+ size_t size;
- commpage_disable_timestamp();
+ /*
+ * 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 (sys time) does not tick,
+ * so the sleep time is the difference between 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 clock we set the wall time to what the
+ * UTC clock returns us.
+ * Setting the wall time to UTC time implies that we loose all the adjustments
+ * done during wake time through adjtime/ntp_adjustime.
+ * The UTC time is the monotonic clock + an offset that can be set
+ * by kernel.
+ * The time slept in this case is the difference between wall time and UTC
+ * at wake.
+ *
+ * IMPORTANT:
+ * We assume that only the kernel is setting the offset of the PMU/RTC and that
+ * it is doing it only througth the settimeofday interface.
+ */
+ if (has_monotonic_clock) {
+#if DEVELOPMENT || DEBUG
+ /*
+ * Just for debugging, get the wake UTC time.
+ */
+ PEGetUTCTimeOfDay(&var_s, &var_us);
+#endif
+ /*
+ * 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__);
+ }
+ wake_abs = monotonic_time.mach_time;
+ absolutetime_to_microtime(wake_abs, &wake_sys_sec, &wake_sys_usec);
- now = mach_absolute_time();
+ monotonic_usec_total = monotonic_time.monotonic_time_usec;
+ wake_sec = monotonic_usec_total / (clock_sec_t)USEC_PER_SEC;
+ wake_usec = monotonic_usec_total % (clock_usec_t)USEC_PER_SEC;
+ } else {
+ /*
+ * Get UTC time and corresponding sys time
+ */
+ PEGetUTCTimeOfDay(&wake_sec, &wake_usec);
+ wake_abs = mach_absolute_time();
+ absolutetime_to_microtime(wake_abs, &wake_sys_sec, &wake_sys_usec);
+ }
- delta = clock_calend.adjdelta;
+#if DEVELOPMENT || DEBUG
+ os_log(OS_LOG_DEFAULT, "time at wake %lu s %d u from %s clock, abs %llu\n", (unsigned long)wake_sec, wake_usec, (has_monotonic_clock)?"monotonic":"UTC", wake_abs);
+ if (has_monotonic_clock) {
+ os_log(OS_LOG_DEFAULT, "UTC time %lu s %d u\n", (unsigned long)var_s, var_us);
+ }
+#endif /* DEVELOPMENT || DEBUG */
- if (delta > 0) {
- clock_calend.offset += clock_calend.adjoffset;
+ s = splclock();
+ clock_lock();
- calend_adjtotal -= delta;
- if (delta > calend_adjtotal) {
- clock_calend.adjdelta = delta = (int32_t)calend_adjtotal;
+ commpage_disable_timestamp();
- nanoseconds_to_absolutetime((uint64_t)delta, &t64);
- clock_calend.adjoffset = (uint32_t)t64;
- }
+#if DEVELOPMENT || DEBUG
+ struct clock_calend clock_calend_cp1 = clock_calend;
+#endif /* DEVELOPMENT || DEBUG */
+
+ /*
+ * We normally expect the UTC/monotonic clock to be always-on and produce
+ * greater readings than the sys counter. There may be corner cases
+ * due to differing clock resolutions (UTC/monotonic clock is likely lower) and
+ * and errors reading the UTC/monotonic clock (some implementations return 0
+ * on error) in which that doesn't hold true.
+ */
+ if ((wake_sys_sec > wake_sec) || ((wake_sys_sec == wake_sec) && (wake_sys_usec > wake_usec))) {
+ os_log_error(OS_LOG_DEFAULT, "WARNING: %s clock is less then sys clock at wake: %lu s %d u vs %lu s %d u, defaulting sleep time to zero\n", (has_monotonic_clock)?"monotonic":"UTC", (unsigned long)wake_sec, wake_usec, (unsigned long)wake_sys_sec, wake_sys_usec);
+ mach_absolutetime_last_sleep = 0;
+ goto done;
}
- 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;
+ if (has_monotonic_clock) {
+ /*
+ * computer the difference monotonic - sys
+ * we already checked that monotonic time is
+ * greater than sys.
+ */
+ diff_sec = wake_sec;
+ diff_usec = wake_usec;
+ // This macro stores the subtraction result in diff_sec and diff_usec
+ TIME_SUB(diff_sec, wake_sys_sec, diff_usec, wake_sys_usec, USEC_PER_SEC);
+ //This function converts diff_sec and diff_usec in bintime
+ clock2bintime(&diff_sec, &diff_usec, &bt);
- nanoseconds_to_absolutetime((uint64_t)-delta, &t64);
- clock_calend.adjoffset = (uint32_t)t64;
- }
+ /*
+ * Safety belt: the monotonic clock will likely have a lower resolution than the sys counter.
+ * It's also possible that the device didn't fully transition to the powered-off state on
+ * the most recent sleep, so the sys counter may not have reset or may have only briefly
+ * turned off. In that case it's possible for the difference between the monotonic clock and the
+ * sys 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 monotonic - abs) and (last wake monotonic - abs)
+ last_sleep_bt = bt;
+ bintime_sub(&last_sleep_bt, &clock_calend.basesleep);
- if (clock_calend.adjdelta != 0)
- clock_calend.adjstart = now;
+ bintime2absolutetime(&last_sleep_bt, &mach_absolutetime_last_sleep);
+ mach_absolutetime_asleep += mach_absolutetime_last_sleep;
+
+ //set basesleep to current monotonic - abs
+ clock_calend.basesleep = bt;
+
+ //update wall time
+ bintime_add(&clock_calend.offset, &last_sleep_bt);
+ bintime_add(&clock_calend.bintime, &last_sleep_bt);
+
+ bintime2usclock(&last_sleep_bt, &var_s, &var_us);
+ os_log(OS_LOG_DEFAULT, "time_slept (%lu s %d u)\n", (unsigned long) var_s, var_us);
+ } else {
+ bintime2usclock(&clock_calend.basesleep, &var_s, &var_us);
+ os_log_error(OS_LOG_DEFAULT, "WARNING: last wake monotonic-sys time (%lu s %d u) is greater then current monotonic-sys time(%lu s %d u), defaulting sleep time to zero\n", (unsigned long) var_s, var_us, (unsigned long) diff_sec, diff_usec);
+
+ mach_absolutetime_last_sleep = 0;
+ }
+ } else {
+ /*
+ * set the wall time to UTC value
+ */
+ bt = get_scaled_time(wake_abs);
+ bintime_add(&bt, &clock_calend.bintime);
+ bintime2usclock(&bt, &wall_time_sec, &wall_time_usec);
+
+ if (wall_time_sec > wake_sec || (wall_time_sec == wake_sec && wall_time_usec > wake_usec)) {
+ os_log(OS_LOG_DEFAULT, "WARNING: wall time (%lu s %d u) is greater than current UTC time (%lu s %d u), defaulting sleep time to zero\n", (unsigned long) wall_time_sec, wall_time_usec, (unsigned long) wake_sec, wake_usec);
+
+ mach_absolutetime_last_sleep = 0;
+ } else {
+ diff_sec = wake_sec;
+ diff_usec = wake_usec;
+ // This macro stores the subtraction result in diff_sec and diff_usec
+ TIME_SUB(diff_sec, wall_time_sec, diff_usec, wall_time_usec, USEC_PER_SEC);
+ //This function converts diff_sec and diff_usec in bintime
+ clock2bintime(&diff_sec, &diff_usec, &bt);
+
+ //time slept in this case is the difference between PMU/RTC and wall time
+ last_sleep_bt = bt;
+
+ bintime2absolutetime(&last_sleep_bt, &mach_absolutetime_last_sleep);
+ mach_absolutetime_asleep += mach_absolutetime_last_sleep;
+
+ //update wall time
+ bintime_add(&clock_calend.offset, &last_sleep_bt);
+ bintime_add(&clock_calend.bintime, &last_sleep_bt);
+
+ bintime2usclock(&last_sleep_bt, &var_s, &var_us);
+ os_log(OS_LOG_DEFAULT, "time_slept (%lu s %d u)\n", (unsigned long)var_s, var_us);
}
+ }
+done:
+ 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);
+
+ commpage_update_mach_continuous_time(mach_absolutetime_asleep);
+ adjust_cont_time_thread_calls();
+
+#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) {
+ print_all_clock_variables("clock_wakeup_calendar: BEFORE", NULL, NULL, NULL, NULL, &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
+}
+
+#endif /* !HAS_CONTINUOUS_HWCLOCK */
+
+/*
+ * 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;
- return (interval);
+ 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_wakeup_calendar:
+ * clock_get_boottime_nanotime:
*
- * Interface to power management, used
- * to initiate the reset of the calendar
- * on wake from sleep event.
+ * Return the boottime, used by sysctl.
*/
void
-clock_wakeup_calendar(void)
+clock_get_boottime_microtime(
+ clock_sec_t *secs,
+ clock_usec_t *microsecs)
{
- thread_call_enter(&calend_wakecall);
+ 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.
*/
static void
mach_wait_until_continue(
- __unused void *parameter,
- wait_result_t wresult)
+ __unused void *parameter,
+ wait_result_t wresult)
{
thread_syscall_return((wresult == THREAD_INTERRUPTED)? KERN_ABORTED: KERN_SUCCESS);
/*NOTREACHED*/
* Parameters: args->deadline Amount of time to wait
*
* Returns: 0 Success
- * !0 Not success
+ * !0 Not success
*
*/
kern_return_t
mach_wait_until_trap(
- struct mach_wait_until_trap_args *args)
+ struct mach_wait_until_trap_args *args)
{
- uint64_t deadline = args->deadline;
- wait_result_t wresult;
+ uint64_t deadline = args->deadline;
+ wait_result_t wresult;
wresult = assert_wait_deadline_with_leeway((event_t)mach_wait_until_trap, THREAD_ABORTSAFE,
- TIMEOUT_URGENCY_USER_NORMAL, deadline, 0);
- if (wresult == THREAD_WAITING)
+ TIMEOUT_URGENCY_USER_NORMAL, deadline, 0);
+ if (wresult == THREAD_WAITING) {
wresult = thread_block(mach_wait_until_continue);
+ }
- return ((wresult == THREAD_INTERRUPTED)? KERN_ABORTED: KERN_SUCCESS);
+ return (wresult == THREAD_INTERRUPTED)? KERN_ABORTED: KERN_SUCCESS;
}
void
clock_delay_until(
- uint64_t deadline)
+ uint64_t deadline)
{
- uint64_t now = mach_absolute_time();
+ uint64_t now = mach_absolute_time();
- if (now >= deadline)
+ if (now >= deadline) {
return;
+ }
_clock_delay_until_deadline(deadline - now, deadline);
}
*/
void
_clock_delay_until_deadline(
- uint64_t interval,
- uint64_t deadline)
+ uint64_t interval,
+ uint64_t deadline)
{
+ _clock_delay_until_deadline_with_leeway(interval, deadline, 0);
+}
- if (interval == 0)
+/*
+ * Like _clock_delay_until_deadline, but it accepts a
+ * leeway value.
+ */
+void
+_clock_delay_until_deadline_with_leeway(
+ uint64_t interval,
+ uint64_t deadline,
+ uint64_t leeway)
+{
+ if (interval == 0) {
return;
+ }
- if ( ml_delay_should_spin(interval) ||
- get_preemption_level() != 0 ||
- ml_get_interrupts_enabled() == FALSE ) {
+ if (ml_delay_should_spin(interval) ||
+ get_preemption_level() != 0 ||
+ ml_get_interrupts_enabled() == FALSE) {
machine_delay_until(interval, deadline);
} else {
- assert_wait_deadline((event_t)clock_delay_until, THREAD_UNINT, deadline);
+ /*
+ * For now, assume a leeway request of 0 means the client does not want a leeway
+ * value. We may want to change this interpretation in the future.
+ */
+
+ if (leeway) {
+ assert_wait_deadline_with_leeway((event_t)clock_delay_until, THREAD_UNINT, TIMEOUT_URGENCY_LEEWAY, deadline, leeway);
+ } else {
+ assert_wait_deadline((event_t)clock_delay_until, THREAD_UNINT, deadline);
+ }
thread_block(THREAD_CONTINUE_NULL);
}
}
-
void
delay_for_interval(
- uint32_t interval,
- uint32_t scale_factor)
+ uint32_t interval,
+ uint32_t scale_factor)
{
- uint64_t abstime;
+ uint64_t abstime;
clock_interval_to_absolutetime_interval(interval, scale_factor, &abstime);
_clock_delay_until_deadline(abstime, mach_absolute_time() + abstime);
}
+void
+delay_for_interval_with_leeway(
+ uint32_t interval,
+ uint32_t leeway,
+ uint32_t scale_factor)
+{
+ uint64_t abstime_interval;
+ uint64_t abstime_leeway;
+
+ clock_interval_to_absolutetime_interval(interval, scale_factor, &abstime_interval);
+ clock_interval_to_absolutetime_interval(leeway, scale_factor, &abstime_leeway);
+
+ _clock_delay_until_deadline_with_leeway(abstime_interval, mach_absolute_time() + abstime_interval, abstime_leeway);
+}
+
void
delay(
- int usec)
+ int usec)
{
delay_for_interval((usec < 0)? -usec: usec, NSEC_PER_USEC);
}
*/
void
clock_interval_to_deadline(
- uint32_t interval,
- uint32_t scale_factor,
- uint64_t *result)
+ uint32_t interval,
+ uint32_t scale_factor,
+ uint64_t *result)
{
- uint64_t abstime;
+ uint64_t abstime;
clock_interval_to_absolutetime_interval(interval, scale_factor, &abstime);
- *result = mach_absolute_time() + abstime;
+ if (os_add_overflow(mach_absolute_time(), abstime, result)) {
+ *result = UINT64_MAX;
+ }
}
void
clock_absolutetime_interval_to_deadline(
- uint64_t abstime,
- uint64_t *result)
+ uint64_t abstime,
+ uint64_t *result)
{
- *result = mach_absolute_time() + abstime;
+ if (os_add_overflow(mach_absolute_time(), abstime, result)) {
+ *result = UINT64_MAX;
+ }
+}
+
+void
+clock_continuoustime_interval_to_deadline(
+ uint64_t conttime,
+ uint64_t *result)
+{
+ if (os_add_overflow(mach_continuous_time(), conttime, result)) {
+ *result = UINT64_MAX;
+ }
}
void
clock_get_uptime(
- uint64_t *result)
+ uint64_t *result)
{
*result = mach_absolute_time();
}
void
clock_deadline_for_periodic_event(
- uint64_t interval,
- uint64_t abstime,
- uint64_t *deadline)
+ uint64_t interval,
+ uint64_t abstime,
+ uint64_t *deadline)
{
assert(interval != 0);
- *deadline += interval;
+ // *deadline += interval;
+ if (os_add_overflow(*deadline, interval, deadline)) {
+ *deadline = UINT64_MAX;
+ }
if (*deadline <= abstime) {
- *deadline = abstime + interval;
+ // *deadline = abstime + interval;
+ if (os_add_overflow(abstime, interval, deadline)) {
+ *deadline = UINT64_MAX;
+ }
+
abstime = mach_absolute_time();
+ if (*deadline <= abstime) {
+ // *deadline = abstime + interval;
+ if (os_add_overflow(abstime, interval, deadline)) {
+ *deadline = UINT64_MAX;
+ }
+ }
+ }
+}
- if (*deadline <= abstime)
- *deadline = abstime + interval;
+uint64_t
+mach_continuous_time(void)
+{
+#if HAS_CONTINUOUS_HWCLOCK
+ return ml_get_hwclock();
+#else
+ 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;
+ }
}
+#endif
}
-#if CONFIG_DTRACE
+uint64_t
+mach_continuous_approximate_time(void)
+{
+#if HAS_CONTINUOUS_HWCLOCK
+ return ml_get_hwclock();
+#else
+ 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;
+ }
+ }
+#endif
+}
+
+/*
+ * 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
/*
* clock_get_calendar_nanotime_nowait
*/
void
clock_get_calendar_nanotime_nowait(
- clock_sec_t *secs,
- clock_nsec_t *nanosecs)
+ clock_sec_t *secs,
+ clock_nsec_t *nanosecs)
{
int i = 0;
- uint64_t now;
+ uint64_t now;
struct unlocked_clock_calend stable;
+ struct bintime bt;
for (;;) {
- stable = flipflop[i]; /* take snapshot */
+ stable = flipflop[i]; /* take snapshot */
/*
* Use a barrier instructions to ensure atomicity. We AND
* off the "in progress" bit to get the current generation
* count.
*/
- (void)hw_atomic_and(&stable.gen, ~(uint32_t)1);
+ os_atomic_andnot(&stable.gen, 1, relaxed);
/*
* If an update _is_ in progress, the generation count will be
* and if we caught it at a good time, it will be equal (and
* our snapshot is threfore stable).
*/
- if (flipflop[i].gen == stable.gen)
+ 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;
+ bt = get_scaled_time(now);
- if (now > stable.calend.adjstart) {
- t32 = (uint32_t)(now - stable.calend.adjstart);
+ bintime_add(&bt, &clock_calend.bintime);
- if (t32 > stable.calend.adjoffset)
- now -= stable.calend.adjoffset;
- else
- now = stable.calend.adjstart;
- }
- }
-
- now += stable.calend.offset;
-
- absolutetime_to_microtime(now, secs, nanosecs);
- *nanosecs *= NSEC_PER_USEC;
-
- *secs += (clock_sec_t)stable.calend.epoch;
+ bintime2nsclock(&bt, secs, nanosecs);
}
-static void
+static void
clock_track_calend_nowait(void)
{
int i;
* will flag an update in progress to an async caller trying
* to examine the contents.
*/
- (void)hw_atomic_or(&flipflop[i].gen, 1);
+ os_atomic_or(&flipflop[i].gen, 1, relaxed);
flipflop[i].calend = tmp;
* count after taking a copy while in progress, the count
* will be off by two.
*/
- (void)hw_atomic_add(&flipflop[i].gen, 1);
+ os_atomic_inc(&flipflop[i].gen, relaxed);
}
}
-#endif /* CONFIG_DTRACE */
-
+#endif /* CONFIG_DTRACE */
projects / apple / xnu.git / blobdiff