[RFC][PATCH - 1/13] NTP cleanup: Move NTP code into ntp.c
From: john stultz (johnstul_at_us.ibm.com)
Date: 08/11/05
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To: lkml <linux-kernel@vger.kernel.org> Date: Wed, 10 Aug 2005 18:23:04 -0700
All,
This patch moves the generic NTP code from time.c and timer.c into
ntp.c. It makes most of the NTP variables static providing more
understandable interfaces like ntp_synced() and ntp_clear().
Since some of the newly made static variables are used in arch generic
code, this patch alone will not compile. Thus this patch requires part 2
of the series which fixes the arch specific uses of the newly static
variables.
Any comments or feedback would be greatly appreciated.
thanks
-john
linux-2.6.13-rc6_timeofday-ntp-part1_B5.patch
============================================
diff --git a/include/linux/ntp.h b/include/linux/ntp.h
new file mode 100644
--- /dev/null
+++ b/include/linux/ntp.h
@@ -0,0 +1,31 @@
+/* linux/include/linux/ntp.h
+ *
+ * This file NTP state machine accessor functions.
+ */
+
+#ifndef _LINUX_NTP_H
+#define _LINUX_NTP_H
+#include <linux/types.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+
+/* NTP state machine interfaces */
+void ntp_advance(void);
+int ntp_adjtimex(struct timex*);
+void second_overflow(void);
+void ntp_clear(void);
+int ntp_synced(void);
+long ntp_get_fixed_ns_adjustment(void);
+
+
+extern int tickadj;
+extern long time_adjust;
+
+/* Due to ppc64 having its own NTP code,
+ * these variables cannot be made static just yet
+ */
+extern long time_offset;
+extern long time_freq;
+extern long time_constant;
+
+#endif
diff --git a/include/linux/timex.h b/include/linux/timex.h
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -226,39 +226,6 @@ struct timex {
*/
extern unsigned long tick_usec; /* USER_HZ period (usec) */
extern unsigned long tick_nsec; /* ACTHZ period (nsec) */
-extern int tickadj; /* amount of adjustment per tick */
-
-/*
- * phase-lock loop variables
- */
-extern int time_state; /* clock status */
-extern int time_status; /* clock synchronization status bits */
-extern long time_offset; /* time adjustment (us) */
-extern long time_constant; /* pll time constant */
-extern long time_tolerance; /* frequency tolerance (ppm) */
-extern long time_precision; /* clock precision (us) */
-extern long time_maxerror; /* maximum error */
-extern long time_esterror; /* estimated error */
-
-extern long time_freq; /* frequency offset (scaled ppm) */
-extern long time_reftime; /* time at last adjustment (s) */
-
-extern long time_adjust; /* The amount of adjtime left */
-extern long time_next_adjust; /* Value for time_adjust at next tick */
-
-/* interface variables pps->timer interrupt */
-extern long pps_offset; /* pps time offset (us) */
-extern long pps_jitter; /* time dispersion (jitter) (us) */
-extern long pps_freq; /* frequency offset (scaled ppm) */
-extern long pps_stabil; /* frequency dispersion (scaled ppm) */
-extern long pps_valid; /* pps signal watchdog counter */
-
-/* interface variables pps->adjtimex */
-extern int pps_shift; /* interval duration (s) (shift) */
-extern long pps_jitcnt; /* jitter limit exceeded */
-extern long pps_calcnt; /* calibration intervals */
-extern long pps_errcnt; /* calibration errors */
-extern long pps_stbcnt; /* stability limit exceeded */
#ifdef CONFIG_TIME_INTERPOLATION
diff --git a/kernel/Makefile b/kernel/Makefile
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -7,7 +7,7 @@ obj-y = sched.o fork.o exec_domain.o
sysctl.o capability.o ptrace.o timer.o user.o \
signal.o sys.o kmod.o workqueue.o pid.o \
rcupdate.o intermodule.o extable.o params.o posix-timers.o \
- kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o
+ kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o ntp.o
obj-$(CONFIG_FUTEX) += futex.o
obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
diff --git a/kernel/ntp.c b/kernel/ntp.c
new file mode 100644
--- /dev/null
+++ b/kernel/ntp.c
@@ -0,0 +1,490 @@
+/********************************************************************
+* linux/kernel/ntp.c
+*
+* NTP state machine and time scaling code.
+*
+* Code moved from kernel/time.c and kernel/timer.c
+* Please see those files for original copyrights.
+*
+* This program is free software; you can redistribute it and/or modify
+* it under the terms of the GNU General Public License as published by
+* the Free Software Foundation; either version 2 of the License, or
+* (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software
+* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*
+* Notes:
+*
+* Hopefully you should never have to understand or touch
+* any of the code below. but don't let that keep you from trying!
+*
+* This code is loosely based on David Mills' RFC 1589 and its
+* updates. Please see the following for more details:
+* http://www.eecis.udel.edu/~mills/database/rfc/rfc1589.txt
+* http://www.eecis.udel.edu/~mills/database/reports/kern/kernb.pdf
+*
+* NOTE: To simplify the code, we do not implement any of
+* the PPS code, as the code that uses it never was merged.
+* -johnstul@us.ibm.com
+*
+*********************************************************************/
+
+#include <linux/ntp.h>
+#include <linux/jiffies.h>
+#include <linux/errno.h>
+
+#ifdef CONFIG_TIME_INTERPOLATION
+void time_interpolator_update(long delta_nsec);
+#else
+#define time_interpolator_update(x) do {} while (0)
+#endif
+
+
+static long pps_offset; /* pps time offset (us) */
+static long pps_jitter = MAXTIME; /* time dispersion (jitter) (us) */
+
+static long pps_freq; /* frequency offset (scaled ppm) */
+static long pps_stabil = MAXFREQ; /* frequency dispersion (scaled ppm) */
+
+static long pps_valid = PPS_VALID; /* pps signal watchdog counter */
+
+static int pps_shift = PPS_SHIFT; /* interval duration (s) (shift) */
+
+static long pps_jitcnt; /* jitter limit exceeded */
+static long pps_calcnt; /* calibration intervals */
+static long pps_errcnt; /* calibration errors */
+static long pps_stbcnt; /* stability limit exceeded */
+
+/* Don't completely fail for HZ > 500. */
+int tickadj = 500/HZ ? : 1; /* microsecs */
+
+
+/*
+ * phase-lock loop variables
+ */
+/* TIME_ERROR prevents overwriting the CMOS clock */
+static int time_state = TIME_OK; /* clock synchronization status */
+static int time_status = STA_UNSYNC; /* clock status bits */
+long time_offset; /* time adjustment (us) */
+long time_constant = 2; /* pll time constant */
+static long time_tolerance = MAXFREQ; /* frequency tolerance (ppm) */
+static long time_precision = 1; /* clock precision (us) */
+static long time_maxerror = NTP_PHASE_LIMIT; /* maximum error (us) */
+static long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */
+static long time_phase; /* phase offset (scaled us) */
+long time_freq = (((NSEC_PER_SEC + HZ/2) % HZ - HZ/2) << SHIFT_USEC) / NSEC_PER_USEC;
+ /* frequency offset (scaled ppm) */
+static long time_adj; /* tick adjust (scaled 1 / HZ) */
+static long time_reftime; /* time at last adjustment (s) */
+long time_adjust;
+static long time_next_adjust;
+
+static long fixed_tick_ns_adj;
+
+void ntp_advance(void)
+{
+ long time_adjust_step;
+
+ if ( (time_adjust_step = time_adjust) != 0 ) {
+ /* We are doing an adjtime thing.
+ *
+ * Prepare time_adjust_step to be within bounds.
+ * Note that a positive time_adjust means we want the clock
+ * to run faster.
+ *
+ * Limit the amount of the step to be in the range
+ * -tickadj .. +tickadj
+ */
+ if (time_adjust > tickadj)
+ time_adjust_step = tickadj;
+ else if (time_adjust < -tickadj)
+ time_adjust_step = -tickadj;
+
+ /* Reduce by this step the amount of time left */
+ time_adjust -= time_adjust_step;
+ }
+ fixed_tick_ns_adj = time_adjust_step * 1000;
+
+ /*
+ * Advance the phase, once it gets to one microsecond, then
+ * advance the tick more.
+ */
+ time_phase += time_adj;
+ if (time_phase <= -FINENSEC) {
+ long ltemp = -time_phase >> (SHIFT_SCALE - 10);
+ time_phase += ltemp << (SHIFT_SCALE - 10);
+ fixed_tick_ns_adj -= ltemp;
+ } else if (time_phase >= FINENSEC) {
+ long ltemp = time_phase >> (SHIFT_SCALE - 10);
+ time_phase -= ltemp << (SHIFT_SCALE - 10);
+ fixed_tick_ns_adj += ltemp;
+ }
+
+ /* Changes by adjtime() do not take effect till next tick. */
+ if (time_next_adjust != 0) {
+ time_adjust = time_next_adjust;
+ time_next_adjust = 0;
+ }
+}
+
+
+/*
+ * this routine handles the overflow of the microsecond field
+ *
+ * The tricky bits of code to handle the accurate clock support
+ * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame.
+ * They were originally developed for SUN and DEC kernels.
+ * All the kudos should go to Dave for this stuff.
+ *
+ */
+void second_overflow(void)
+{
+ long ltemp;
+
+ /* Bump the maxerror field */
+ time_maxerror += time_tolerance >> SHIFT_USEC;
+ if ( time_maxerror > NTP_PHASE_LIMIT ) {
+ time_maxerror = NTP_PHASE_LIMIT;
+ time_status |= STA_UNSYNC;
+ }
+
+ /*
+ * Leap second processing. If in leap-insert state at
+ * the end of the day, the system clock is set back one
+ * second; if in leap-delete state, the system clock is
+ * set ahead one second. The microtime() routine or
+ * external clock driver will insure that reported time
+ * is always monotonic. The ugly divides should be
+ * replaced.
+ */
+ switch (time_state) {
+
+ case TIME_OK:
+ if (time_status & STA_INS)
+ time_state = TIME_INS;
+ else if (time_status & STA_DEL)
+ time_state = TIME_DEL;
+ break;
+
+ case TIME_INS:
+ if (xtime.tv_sec % 86400 == 0) {
+ xtime.tv_sec--;
+ wall_to_monotonic.tv_sec++;
+ /* The timer interpolator will make time change gradually instead
+ * of an immediate jump by one second.
+ */
+ time_interpolator_update(-NSEC_PER_SEC);
+ time_state = TIME_OOP;
+ clock_was_set();
+ printk(KERN_NOTICE "Clock: inserting leap second 23:59:60 UTC\n");
+ }
+ break;
+
+ case TIME_DEL:
+ if ((xtime.tv_sec + 1) % 86400 == 0) {
+ xtime.tv_sec++;
+ wall_to_monotonic.tv_sec--;
+ /* Use of time interpolator for a gradual change of time */
+ time_interpolator_update(NSEC_PER_SEC);
+ time_state = TIME_WAIT;
+ clock_was_set();
+ printk(KERN_NOTICE "Clock: deleting leap second 23:59:59 UTC\n");
+ }
+ break;
+
+ case TIME_OOP:
+ time_state = TIME_WAIT;
+ break;
+
+ case TIME_WAIT:
+ if (!(time_status & (STA_INS | STA_DEL)))
+ time_state = TIME_OK;
+ }
+
+ /*
+ * Compute the phase adjustment for the next second. In
+ * PLL mode, the offset is reduced by a fixed factor
+ * times the time constant. In FLL mode the offset is
+ * used directly. In either mode, the maximum phase
+ * adjustment for each second is clamped so as to spread
+ * the adjustment over not more than the number of
+ * seconds between updates.
+ */
+ if (time_offset < 0) {
+ ltemp = -time_offset;
+ if (!(time_status & STA_FLL))
+ ltemp >>= SHIFT_KG + time_constant;
+ if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE)
+ ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE;
+ time_offset += ltemp;
+ time_adj = -ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
+ } else {
+ ltemp = time_offset;
+ if (!(time_status & STA_FLL))
+ ltemp >>= SHIFT_KG + time_constant;
+ if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE)
+ ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE;
+ time_offset -= ltemp;
+ time_adj = ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
+ }
+
+ /*
+ * Compute the frequency estimate and additional phase
+ * adjustment due to frequency error for the next
+ * second. When the PPS signal is engaged, gnaw on the
+ * watchdog counter and update the frequency computed by
+ * the pll and the PPS signal.
+ */
+ pps_valid++;
+ if (pps_valid == PPS_VALID) { /* PPS signal lost */
+ pps_jitter = MAXTIME;
+ pps_stabil = MAXFREQ;
+ time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER |
+ STA_PPSWANDER | STA_PPSERROR);
+ }
+ ltemp = time_freq + pps_freq;
+ if (ltemp < 0)
+ time_adj -= -ltemp >> (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE);
+ else
+ time_adj += ltemp >> (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE);
+
+#if HZ == 100
+ /* Compensate for (HZ==100) != (1 << SHIFT_HZ).
+ * Add 25% and 3.125% to get 128.125; => only 0.125% error (p. 14)
+ */
+ if (time_adj < 0)
+ time_adj -= (-time_adj >> 2) + (-time_adj >> 5);
+ else
+ time_adj += (time_adj >> 2) + (time_adj >> 5);
+#endif
+#if HZ == 1000
+ /* Compensate for (HZ==1000) != (1 << SHIFT_HZ).
+ * Add 1.5625% and 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
+ */
+ if (time_adj < 0)
+ time_adj -= (-time_adj >> 6) + (-time_adj >> 7);
+ else
+ time_adj += (time_adj >> 6) + (time_adj >> 7);
+#endif
+}
+
+/* adjtimex mainly allows reading (and writing, if superuser) of
+ * kernel time-keeping variables. used by xntpd.
+ */
+int ntp_adjtimex(struct timex *txc)
+{
+ long ltemp, mtemp, save_adjust;
+ int result;
+
+ /* Now we validate the data before disabling interrupts */
+
+ if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT)
+ /* singleshot must not be used with any other mode bits */
+ if (txc->modes != ADJ_OFFSET_SINGLESHOT)
+ return -EINVAL;
+
+ if (txc->modes != ADJ_OFFSET_SINGLESHOT && (txc->modes & ADJ_OFFSET))
+ /* adjustment Offset limited to +- .512 seconds */
+ if (txc->offset <= - MAXPHASE || txc->offset >= MAXPHASE )
+ return -EINVAL;
+
+ /* if the quartz is off by more than 10% something is VERY wrong ! */
+ if (txc->modes & ADJ_TICK)
+ if (txc->tick < 900000/USER_HZ ||
+ txc->tick > 1100000/USER_HZ)
+ return -EINVAL;
+
+ write_seqlock_irq(&xtime_lock);
+ result = time_state; /* mostly `TIME_OK' */
+
+ /* Save for later - semantics of adjtime is to return old value */
+ save_adjust = time_next_adjust ? time_next_adjust : time_adjust;
+
+ /* If there are input parameters, then process them */
+ if (txc->modes) {
+ if (txc->modes & ADJ_STATUS) /* only set allowed bits */
+ time_status = (txc->status & ~STA_RONLY) |
+ (time_status & STA_RONLY);
+
+ if (txc->modes & ADJ_FREQUENCY) { /* p. 22 */
+ if (txc->freq > MAXFREQ || txc->freq < -MAXFREQ) {
+ result = -EINVAL;
+ goto leave;
+ }
+ time_freq = txc->freq - pps_freq;
+ }
+
+ if (txc->modes & ADJ_MAXERROR) {
+ if (txc->maxerror < 0
+ || txc->maxerror >= NTP_PHASE_LIMIT) {
+ result = -EINVAL;
+ goto leave;
+ }
+ time_maxerror = txc->maxerror;
+ }
+
+ if (txc->modes & ADJ_ESTERROR) {
+ if (txc->esterror < 0
+ || txc->esterror >= NTP_PHASE_LIMIT) {
+ result = -EINVAL;
+ goto leave;
+ }
+ time_esterror = txc->esterror;
+ }
+
+ if (txc->modes & ADJ_TIMECONST) { /* p. 24 */
+ if (txc->constant < 0) { /* NTP v4 uses values > 6 */
+ result = -EINVAL;
+ goto leave;
+ }
+ time_constant = txc->constant;
+ }
+
+ if (txc->modes & ADJ_OFFSET) { /* values checked earlier */
+ if (txc->modes == ADJ_OFFSET_SINGLESHOT) {
+ /* adjtime() is independent from ntp_adjtime() */
+ if ((time_next_adjust = txc->offset) == 0)
+ time_adjust = 0;
+ } else if ( time_status & (STA_PLL | STA_PPSTIME) ) {
+ ltemp = (time_status
+ & (STA_PPSTIME | STA_PPSSIGNAL))
+ == (STA_PPSTIME | STA_PPSSIGNAL) ?
+ pps_offset : txc->offset;
+
+ /*
+ * Scale the phase adjustment and
+ * clamp to the operating range.
+ */
+ if (ltemp > MAXPHASE)
+ time_offset = MAXPHASE << SHIFT_UPDATE;
+ else if (ltemp < -MAXPHASE)
+ time_offset = -(MAXPHASE
+ << SHIFT_UPDATE);
+ else
+ time_offset = ltemp << SHIFT_UPDATE;
+
+ /*
+ * Select whether the frequency is to be controlled
+ * and in which mode (PLL or FLL). Clamp to the operating
+ * range. Ugly multiply/divide should be replaced someday.
+ */
+
+ if (time_status & STA_FREQHOLD || time_reftime == 0)
+ time_reftime = xtime.tv_sec;
+
+ mtemp = xtime.tv_sec - time_reftime;
+ time_reftime = xtime.tv_sec;
+
+ if (time_status & STA_FLL) {
+ if (mtemp >= MINSEC) {
+ ltemp = (time_offset / mtemp) << (SHIFT_USEC -
+ SHIFT_UPDATE);
+ if (ltemp < 0)
+ time_freq -= -ltemp >> SHIFT_KH;
+ else
+ time_freq += ltemp >> SHIFT_KH;
+ } else /* calibration interval too short (p. 12) */
+ result = TIME_ERROR;
+ } else { /* PLL mode */
+ if (mtemp < MAXSEC) {
+ ltemp *= mtemp;
+ if (ltemp < 0)
+ time_freq -= -ltemp >> (time_constant +
+ time_constant +
+ SHIFT_KF - SHIFT_USEC);
+ else
+ time_freq += ltemp >> (time_constant +
+ time_constant +
+ SHIFT_KF - SHIFT_USEC);
+ } else /* calibration interval too long (p. 12) */
+ result = TIME_ERROR;
+ }
+
+ if (time_freq > time_tolerance)
+ time_freq = time_tolerance;
+ else if (time_freq < -time_tolerance)
+ time_freq = -time_tolerance;
+ } /* STA_PLL || STA_PPSTIME */
+ } /* txc->modes & ADJ_OFFSET */
+
+ if (txc->modes & ADJ_TICK) {
+ tick_usec = txc->tick;
+ tick_nsec = TICK_USEC_TO_NSEC(tick_usec);
+ }
+ } /* txc->modes */
+leave:
+
+ if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0
+ || ((time_status & (STA_PPSFREQ|STA_PPSTIME)) != 0
+ && (time_status & STA_PPSSIGNAL) == 0)
+ /* p. 24, (b) */
+ || ((time_status & (STA_PPSTIME|STA_PPSJITTER))
+ == (STA_PPSTIME|STA_PPSJITTER))
+ /* p. 24, (c) */
+ || ((time_status & STA_PPSFREQ) != 0
+ && (time_status & (STA_PPSWANDER|STA_PPSERROR)) != 0))
+ /* p. 24, (d) */
+ result = TIME_ERROR;
+
+ if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT)
+ txc->offset = save_adjust;
+ else {
+ if (time_offset < 0)
+ txc->offset = -(-time_offset >> SHIFT_UPDATE);
+ else
+ txc->offset = time_offset >> SHIFT_UPDATE;
+ }
+ txc->freq = time_freq + pps_freq;
+ txc->maxerror = time_maxerror;
+ txc->esterror = time_esterror;
+ txc->status = time_status;
+ txc->constant = time_constant;
+ txc->precision = time_precision;
+ txc->tolerance = time_tolerance;
+ txc->tick = tick_usec;
+ txc->ppsfreq = pps_freq;
+ txc->jitter = pps_jitter >> PPS_AVG;
+ txc->shift = pps_shift;
+ txc->stabil = pps_stabil;
+ txc->jitcnt = pps_jitcnt;
+ txc->calcnt = pps_calcnt;
+ txc->errcnt = pps_errcnt;
+ txc->stbcnt = pps_stbcnt;
+ write_sequnlock_irq(&xtime_lock);
+ do_gettimeofday(&txc->time);
+ return result;
+}
+
+/**
+ * ntp_clear - Clears the NTP state machine.
+ *
+ * Must be called while holding a write on the xtime_lock
+ */
+void ntp_clear(void)
+{
+ time_adjust = 0; /* stop active adjtime() */
+ time_status |= STA_UNSYNC;
+ time_maxerror = NTP_PHASE_LIMIT;
+ time_esterror = NTP_PHASE_LIMIT;
+}
+
+/**
+ * ntp_synced - Returns 1 if the NTP status is not UNSYNC
+ *
+ */
+int ntp_synced(void)
+{
+ return !(time_status & STA_UNSYNC);
+}
+
+long ntp_get_fixed_ns_adjustment(void)
+{
+ return fixed_tick_ns_adj;
+}
diff --git a/kernel/time.c b/kernel/time.c
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -35,6 +35,7 @@
#include <linux/security.h>
#include <linux/fs.h>
#include <linux/module.h>
+#include <linux/ntp.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
@@ -198,20 +199,6 @@ asmlinkage long sys_settimeofday(struct
return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL);
}
-long pps_offset; /* pps time offset (us) */
-long pps_jitter = MAXTIME; /* time dispersion (jitter) (us) */
-
-long pps_freq; /* frequency offset (scaled ppm) */
-long pps_stabil = MAXFREQ; /* frequency dispersion (scaled ppm) */
-
-long pps_valid = PPS_VALID; /* pps signal watchdog counter */
-
-int pps_shift = PPS_SHIFT; /* interval duration (s) (shift) */
-
-long pps_jitcnt; /* jitter limit exceeded */
-long pps_calcnt; /* calibration intervals */
-long pps_errcnt; /* calibration errors */
-long pps_stbcnt; /* stability limit exceeded */
/* hook for a loadable hardpps kernel module */
void (*hardpps_ptr)(struct timeval *);
@@ -229,184 +216,14 @@ void __attribute__ ((weak)) notify_arch_
*/
int do_adjtimex(struct timex *txc)
{
- long ltemp, mtemp, save_adjust;
int result;
/* In order to modify anything, you gotta be super-user! */
if (txc->modes && !capable(CAP_SYS_TIME))
return -EPERM;
- /* Now we validate the data before disabling interrupts */
-
- if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT)
- /* singleshot must not be used with any other mode bits */
- if (txc->modes != ADJ_OFFSET_SINGLESHOT)
- return -EINVAL;
-
- if (txc->modes != ADJ_OFFSET_SINGLESHOT && (txc->modes & ADJ_OFFSET))
- /* adjustment Offset limited to +- .512 seconds */
- if (txc->offset <= - MAXPHASE || txc->offset >= MAXPHASE )
- return -EINVAL;
-
- /* if the quartz is off by more than 10% something is VERY wrong ! */
- if (txc->modes & ADJ_TICK)
- if (txc->tick < 900000/USER_HZ ||
- txc->tick > 1100000/USER_HZ)
- return -EINVAL;
-
- write_seqlock_irq(&xtime_lock);
- result = time_state; /* mostly `TIME_OK' */
-
- /* Save for later - semantics of adjtime is to return old value */
- save_adjust = time_next_adjust ? time_next_adjust : time_adjust;
-
-#if 0 /* STA_CLOCKERR is never set yet */
- time_status &= ~STA_CLOCKERR; /* reset STA_CLOCKERR */
-#endif
- /* If there are input parameters, then process them */
- if (txc->modes)
- {
- if (txc->modes & ADJ_STATUS) /* only set allowed bits */
- time_status = (txc->status & ~STA_RONLY) |
- (time_status & STA_RONLY);
-
- if (txc->modes & ADJ_FREQUENCY) { /* p. 22 */
- if (txc->freq > MAXFREQ || txc->freq < -MAXFREQ) {
- result = -EINVAL;
- goto leave;
- }
- time_freq = txc->freq - pps_freq;
- }
-
- if (txc->modes & ADJ_MAXERROR) {
- if (txc->maxerror < 0 || txc->maxerror >= NTP_PHASE_LIMIT) {
- result = -EINVAL;
- goto leave;
- }
- time_maxerror = txc->maxerror;
- }
-
- if (txc->modes & ADJ_ESTERROR) {
- if (txc->esterror < 0 || txc->esterror >= NTP_PHASE_LIMIT) {
- result = -EINVAL;
- goto leave;
- }
- time_esterror = txc->esterror;
- }
-
- if (txc->modes & ADJ_TIMECONST) { /* p. 24 */
- if (txc->constant < 0) { /* NTP v4 uses values > 6 */
- result = -EINVAL;
- goto leave;
- }
- time_constant = txc->constant;
- }
-
- if (txc->modes & ADJ_OFFSET) { /* values checked earlier */
- if (txc->modes == ADJ_OFFSET_SINGLESHOT) {
- /* adjtime() is independent from ntp_adjtime() */
- if ((time_next_adjust = txc->offset) == 0)
- time_adjust = 0;
- }
- else if ( time_status & (STA_PLL | STA_PPSTIME) ) {
- ltemp = (time_status & (STA_PPSTIME | STA_PPSSIGNAL)) ==
- (STA_PPSTIME | STA_PPSSIGNAL) ?
- pps_offset : txc->offset;
-
- /*
- * Scale the phase adjustment and
- * clamp to the operating range.
- */
- if (ltemp > MAXPHASE)
- time_offset = MAXPHASE << SHIFT_UPDATE;
- else if (ltemp < -MAXPHASE)
- time_offset = -(MAXPHASE << SHIFT_UPDATE);
- else
- time_offset = ltemp << SHIFT_UPDATE;
-
- /*
- * Select whether the frequency is to be controlled
- * and in which mode (PLL or FLL). Clamp to the operating
- * range. Ugly multiply/divide should be replaced someday.
- */
-
- if (time_status & STA_FREQHOLD || time_reftime == 0)
- time_reftime = xtime.tv_sec;
- mtemp = xtime.tv_sec - time_reftime;
- time_reftime = xtime.tv_sec;
- if (time_status & STA_FLL) {
- if (mtemp >= MINSEC) {
- ltemp = (time_offset / mtemp) << (SHIFT_USEC -
- SHIFT_UPDATE);
- if (ltemp < 0)
- time_freq -= -ltemp >> SHIFT_KH;
- else
- time_freq += ltemp >> SHIFT_KH;
- } else /* calibration interval too short (p. 12) */
- result = TIME_ERROR;
- } else { /* PLL mode */
- if (mtemp < MAXSEC) {
- ltemp *= mtemp;
- if (ltemp < 0)
- time_freq -= -ltemp >> (time_constant +
- time_constant +
- SHIFT_KF - SHIFT_USEC);
- else
- time_freq += ltemp >> (time_constant +
- time_constant +
- SHIFT_KF - SHIFT_USEC);
- } else /* calibration interval too long (p. 12) */
- result = TIME_ERROR;
- }
- if (time_freq > time_tolerance)
- time_freq = time_tolerance;
- else if (time_freq < -time_tolerance)
- time_freq = -time_tolerance;
- } /* STA_PLL || STA_PPSTIME */
- } /* txc->modes & ADJ_OFFSET */
- if (txc->modes & ADJ_TICK) {
- tick_usec = txc->tick;
- tick_nsec = TICK_USEC_TO_NSEC(tick_usec);
- }
- } /* txc->modes */
-leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0
- || ((time_status & (STA_PPSFREQ|STA_PPSTIME)) != 0
- && (time_status & STA_PPSSIGNAL) == 0)
- /* p. 24, (b) */
- || ((time_status & (STA_PPSTIME|STA_PPSJITTER))
- == (STA_PPSTIME|STA_PPSJITTER))
- /* p. 24, (c) */
- || ((time_status & STA_PPSFREQ) != 0
- && (time_status & (STA_PPSWANDER|STA_PPSERROR)) != 0))
- /* p. 24, (d) */
- result = TIME_ERROR;
+ result = ntp_adjtimex(txc);
- if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT)
- txc->offset = save_adjust;
- else {
- if (time_offset < 0)
- txc->offset = -(-time_offset >> SHIFT_UPDATE);
- else
- txc->offset = time_offset >> SHIFT_UPDATE;
- }
- txc->freq = time_freq + pps_freq;
- txc->maxerror = time_maxerror;
- txc->esterror = time_esterror;
- txc->status = time_status;
- txc->constant = time_constant;
- txc->precision = time_precision;
- txc->tolerance = time_tolerance;
- txc->tick = tick_usec;
- txc->ppsfreq = pps_freq;
- txc->jitter = pps_jitter >> PPS_AVG;
- txc->shift = pps_shift;
- txc->stabil = pps_stabil;
- txc->jitcnt = pps_jitcnt;
- txc->calcnt = pps_calcnt;
- txc->errcnt = pps_errcnt;
- txc->stbcnt = pps_stbcnt;
- write_sequnlock_irq(&xtime_lock);
- do_gettimeofday(&txc->time);
notify_arch_cmos_timer();
return(result);
}
@@ -522,10 +339,8 @@ int do_settimeofday (struct timespec *tv
set_normalized_timespec(&xtime, sec, nsec);
set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
- time_adjust = 0; /* stop active adjtime() */
- time_status |= STA_UNSYNC;
- time_maxerror = NTP_PHASE_LIMIT;
- time_esterror = NTP_PHASE_LIMIT;
+ ntp_clear();
+
time_interpolator_reset();
}
write_sequnlock_irq(&xtime_lock);
diff --git a/kernel/timer.c b/kernel/timer.c
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -33,6 +33,7 @@
#include <linux/posix-timers.h>
#include <linux/cpu.h>
#include <linux/syscalls.h>
+#include <linux/ntp.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
@@ -41,7 +42,7 @@
#include <asm/io.h>
#ifdef CONFIG_TIME_INTERPOLATION
-static void time_interpolator_update(long delta_nsec);
+void time_interpolator_update(long delta_nsec);
#else
#define time_interpolator_update(x)
#endif
@@ -597,219 +598,19 @@ struct timespec wall_to_monotonic __attr
EXPORT_SYMBOL(xtime);
-/* Don't completely fail for HZ > 500. */
-int tickadj = 500/HZ ? : 1; /* microsecs */
-
-
-/*
- * phase-lock loop variables
- */
-/* TIME_ERROR prevents overwriting the CMOS clock */
-int time_state = TIME_OK; /* clock synchronization status */
-int time_status = STA_UNSYNC; /* clock status bits */
-long time_offset; /* time adjustment (us) */
-long time_constant = 2; /* pll time constant */
-long time_tolerance = MAXFREQ; /* frequency tolerance (ppm) */
-long time_precision = 1; /* clock precision (us) */
-long time_maxerror = NTP_PHASE_LIMIT; /* maximum error (us) */
-long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */
-static long time_phase; /* phase offset (scaled us) */
-long time_freq = (((NSEC_PER_SEC + HZ/2) % HZ - HZ/2) << SHIFT_USEC) / NSEC_PER_USEC;
- /* frequency offset (scaled ppm)*/
-static long time_adj; /* tick adjust (scaled 1 / HZ) */
-long time_reftime; /* time at last adjustment (s) */
-long time_adjust;
-long time_next_adjust;
-
-/*
- * this routine handles the overflow of the microsecond field
- *
- * The tricky bits of code to handle the accurate clock support
- * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame.
- * They were originally developed for SUN and DEC kernels.
- * All the kudos should go to Dave for this stuff.
- *
- */
-static void second_overflow(void)
-{
- long ltemp;
-
- /* Bump the maxerror field */
- time_maxerror += time_tolerance >> SHIFT_USEC;
- if ( time_maxerror > NTP_PHASE_LIMIT ) {
- time_maxerror = NTP_PHASE_LIMIT;
- time_status |= STA_UNSYNC;
- }
-
- /*
- * Leap second processing. If in leap-insert state at
- * the end of the day, the system clock is set back one
- * second; if in leap-delete state, the system clock is
- * set ahead one second. The microtime() routine or
- * external clock driver will insure that reported time
- * is always monotonic. The ugly divides should be
- * replaced.
- */
- switch (time_state) {
-
- case TIME_OK:
- if (time_status & STA_INS)
- time_state = TIME_INS;
- else if (time_status & STA_DEL)
- time_state = TIME_DEL;
- break;
-
- case TIME_INS:
- if (xtime.tv_sec % 86400 == 0) {
- xtime.tv_sec--;
- wall_to_monotonic.tv_sec++;
- /* The timer interpolator will make time change gradually instead
- * of an immediate jump by one second.
- */
- time_interpolator_update(-NSEC_PER_SEC);
- time_state = TIME_OOP;
- clock_was_set();
- printk(KERN_NOTICE "Clock: inserting leap second 23:59:60 UTC\n");
- }
- break;
-
- case TIME_DEL:
- if ((xtime.tv_sec + 1) % 86400 == 0) {
- xtime.tv_sec++;
- wall_to_monotonic.tv_sec--;
- /* Use of time interpolator for a gradual change of time */
- time_interpolator_update(NSEC_PER_SEC);
- time_state = TIME_WAIT;
- clock_was_set();
- printk(KERN_NOTICE "Clock: deleting leap second 23:59:59 UTC\n");
- }
- break;
-
- case TIME_OOP:
- time_state = TIME_WAIT;
- break;
-
- case TIME_WAIT:
- if (!(time_status & (STA_INS | STA_DEL)))
- time_state = TIME_OK;
- }
-
- /*
- * Compute the phase adjustment for the next second. In
- * PLL mode, the offset is reduced by a fixed factor
- * times the time constant. In FLL mode the offset is
- * used directly. In either mode, the maximum phase
- * adjustment for each second is clamped so as to spread
- * the adjustment over not more than the number of
- * seconds between updates.
- */
- if (time_offset < 0) {
- ltemp = -time_offset;
- if (!(time_status & STA_FLL))
- ltemp >>= SHIFT_KG + time_constant;
- if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE)
- ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE;
- time_offset += ltemp;
- time_adj = -ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
- } else {
- ltemp = time_offset;
- if (!(time_status & STA_FLL))
- ltemp >>= SHIFT_KG + time_constant;
- if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE)
- ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE;
- time_offset -= ltemp;
- time_adj = ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE);
- }
-
- /*
- * Compute the frequency estimate and additional phase
- * adjustment due to frequency error for the next
- * second. When the PPS signal is engaged, gnaw on the
- * watchdog counter and update the frequency computed by
- * the pll and the PPS signal.
- */
- pps_valid++;
- if (pps_valid == PPS_VALID) { /* PPS signal lost */
- pps_jitter = MAXTIME;
- pps_stabil = MAXFREQ;
- time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER |
- STA_PPSWANDER | STA_PPSERROR);
- }
- ltemp = time_freq + pps_freq;
- if (ltemp < 0)
- time_adj -= -ltemp >>
- (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE);
- else
- time_adj += ltemp >>
- (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE);
-
-#if HZ == 100
- /* Compensate for (HZ==100) != (1 << SHIFT_HZ).
- * Add 25% and 3.125% to get 128.125; => only 0.125% error (p. 14)
- */
- if (time_adj < 0)
- time_adj -= (-time_adj >> 2) + (-time_adj >> 5);
- else
- time_adj += (time_adj >> 2) + (time_adj >> 5);
-#endif
-#if HZ == 1000
- /* Compensate for (HZ==1000) != (1 << SHIFT_HZ).
- * Add 1.5625% and 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
- */
- if (time_adj < 0)
- time_adj -= (-time_adj >> 6) + (-time_adj >> 7);
- else
- time_adj += (time_adj >> 6) + (time_adj >> 7);
-#endif
-}
/* in the NTP reference this is called "hardclock()" */
static void update_wall_time_one_tick(void)
{
- long time_adjust_step, delta_nsec;
+ long delta_nsec;
- if ( (time_adjust_step = time_adjust) != 0 ) {
- /* We are doing an adjtime thing.
- *
- * Prepare time_adjust_step to be within bounds.
- * Note that a positive time_adjust means we want the clock
- * to run faster.
- *
- * Limit the amount of the step to be in the range
- * -tickadj .. +tickadj
- */
- if (time_adjust > tickadj)
- time_adjust_step = tickadj;
- else if (time_adjust < -tickadj)
- time_adjust_step = -tickadj;
+ ntp_advance();
+
+ delta_nsec = tick_nsec + ntp_get_fixed_ns_adjustment();
- /* Reduce by this step the amount of time left */
- time_adjust -= time_adjust_step;
- }
- delta_nsec = tick_nsec + time_adjust_step * 1000;
- /*
- * Advance the phase, once it gets to one microsecond, then
- * advance the tick more.
- */
- time_phase += time_adj;
- if (time_phase <= -FINENSEC) {
- long ltemp = -time_phase >> (SHIFT_SCALE - 10);
- time_phase += ltemp << (SHIFT_SCALE - 10);
- delta_nsec -= ltemp;
- }
- else if (time_phase >= FINENSEC) {
- long ltemp = time_phase >> (SHIFT_SCALE - 10);
- time_phase -= ltemp << (SHIFT_SCALE - 10);
- delta_nsec += ltemp;
- }
xtime.tv_nsec += delta_nsec;
time_interpolator_update(delta_nsec);
- /* Changes by adjtime() do not take effect till next tick. */
- if (time_next_adjust != 0) {
- time_adjust = time_next_adjust;
- time_next_adjust = 0;
- }
}
/*
@@ -1473,7 +1274,7 @@ unsigned long time_interpolator_get_offs
#define INTERPOLATOR_ADJUST 65536
#define INTERPOLATOR_MAX_SKIP 10*INTERPOLATOR_ADJUST
-static void time_interpolator_update(long delta_nsec)
+void time_interpolator_update(long delta_nsec)
{
u64 counter;
unsigned long offset;
-
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