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Subject[RFC][PATCH - 1/13] NTP cleanup: Move NTP code into ntp.c
From
Date
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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