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authorRoman Zippel <zippel@linux-m68k.org>2008-05-01 04:34:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-05-01 08:03:58 -0700
commitee9851b218b8bafa22942b5404505ff3d2d34324 (patch)
tree82e5a421d18bd3d469afd9c4c2827a865b9f19b5 /kernel/time
parentf8bd2258e2d520dff28c855658bd24bdafb5102d (diff)
ntp: cleanup ntp.c
This is mostly a style cleanup of ntp.c and extracts part of do_adjtimex as ntp_update_offset(). Otherwise the functionality is still the same as before. Signed-off-by: Roman Zippel <zippel@linux-m68k.org> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/time')
-rw-r--r--kernel/time/ntp.c173
1 files changed, 91 insertions, 82 deletions
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index dbd6f8905614..2586c30f0658 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -35,7 +35,7 @@ static u64 tick_length, tick_length_base;
/* TIME_ERROR prevents overwriting the CMOS clock */
static int time_state = TIME_OK; /* clock synchronization status */
int time_status = STA_UNSYNC; /* clock status bits */
-static s64 time_offset; /* time adjustment (ns) */
+static s64 time_offset; /* time adjustment (ns) */
static long time_constant = 2; /* pll time constant */
long time_maxerror = NTP_PHASE_LIMIT; /* maximum error (us) */
long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */
@@ -57,6 +57,44 @@ static void ntp_update_frequency(void)
tick_length_base = div_u64(tick_length_base, NTP_INTERVAL_FREQ);
}
+static void ntp_update_offset(long offset)
+{
+ long mtemp;
+ s64 freq_adj;
+
+ if (!(time_status & STA_PLL))
+ return;
+
+ time_offset = offset * NSEC_PER_USEC;
+
+ /*
+ * Scale the phase adjustment and
+ * clamp to the operating range.
+ */
+ time_offset = min(time_offset, (s64)MAXPHASE * NSEC_PER_USEC);
+ time_offset = max(time_offset, (s64)-MAXPHASE * NSEC_PER_USEC);
+
+ /*
+ * Select how the frequency is to be controlled
+ * and in which mode (PLL or FLL).
+ */
+ if (time_status & STA_FREQHOLD || time_reftime == 0)
+ time_reftime = xtime.tv_sec;
+ mtemp = xtime.tv_sec - time_reftime;
+ time_reftime = xtime.tv_sec;
+
+ freq_adj = time_offset * mtemp;
+ freq_adj = shift_right(freq_adj, time_constant * 2 +
+ (SHIFT_PLL + 2) * 2 - SHIFT_NSEC);
+ if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC))
+ freq_adj += div_s64(time_offset << (SHIFT_NSEC - SHIFT_FLL), mtemp);
+ freq_adj += time_freq;
+ freq_adj = min(freq_adj, (s64)MAXFREQ_NSEC);
+ time_freq = max(freq_adj, (s64)-MAXFREQ_NSEC);
+ time_offset = div_s64(time_offset, NTP_INTERVAL_FREQ);
+ time_offset <<= SHIFT_UPDATE;
+}
+
/**
* ntp_clear - Clears the NTP state variables
*
@@ -131,7 +169,7 @@ void second_overflow(void)
break;
case TIME_WAIT:
if (!(time_status & (STA_INS | STA_DEL)))
- time_state = TIME_OK;
+ time_state = TIME_OK;
}
/*
@@ -234,8 +272,7 @@ static inline void notify_cmos_timer(void) { }
*/
int do_adjtimex(struct timex *txc)
{
- long mtemp, save_adjust;
- s64 freq_adj;
+ long save_adjust;
int result;
/* In order to modify anything, you gotta be super-user! */
@@ -272,94 +309,63 @@ int do_adjtimex(struct timex *txc)
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;
+ 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) {
+ if (txc->freq > MAXFREQ || txc->freq < -MAXFREQ) {
+ result = -EINVAL;
+ goto leave;
+ }
+ time_freq = ((s64)txc->freq * NSEC_PER_USEC)
+ >> (SHIFT_USEC - SHIFT_NSEC);
}
- time_freq = ((s64)txc->freq * NSEC_PER_USEC)
- >> (SHIFT_USEC - SHIFT_NSEC);
- }
-
- if (txc->modes & ADJ_MAXERROR) {
- if (txc->maxerror < 0 || txc->maxerror >= NTP_PHASE_LIMIT) {
- result = -EINVAL;
- goto leave;
+
+ if (txc->modes & ADJ_MAXERROR) {
+ if (txc->maxerror < 0 || txc->maxerror >= NTP_PHASE_LIMIT) {
+ result = -EINVAL;
+ goto leave;
+ }
+ time_maxerror = txc->maxerror;
}
- time_maxerror = txc->maxerror;
- }
- if (txc->modes & ADJ_ESTERROR) {
- if (txc->esterror < 0 || txc->esterror >= NTP_PHASE_LIMIT) {
- result = -EINVAL;
- goto leave;
+ if (txc->modes & ADJ_ESTERROR) {
+ if (txc->esterror < 0 || txc->esterror >= NTP_PHASE_LIMIT) {
+ result = -EINVAL;
+ goto leave;
+ }
+ time_esterror = txc->esterror;
}
- time_esterror = txc->esterror;
- }
- if (txc->modes & ADJ_TIMECONST) { /* p. 24 */
- if (txc->constant < 0) { /* NTP v4 uses values > 6 */
- result = -EINVAL;
- goto leave;
+ if (txc->modes & ADJ_TIMECONST) {
+ if (txc->constant < 0) { /* NTP v4 uses values > 6 */
+ result = -EINVAL;
+ goto leave;
+ }
+ time_constant = min(txc->constant + 4, (long)MAXTC);
}
- time_constant = min(txc->constant + 4, (long)MAXTC);
- }
- if (txc->modes & ADJ_OFFSET) { /* values checked earlier */
- if (txc->modes == ADJ_OFFSET_SINGLESHOT) {
- /* adjtime() is independent from ntp_adjtime() */
- time_adjust = txc->offset;
+ if (txc->modes & ADJ_OFFSET) {
+ if (txc->modes == ADJ_OFFSET_SINGLESHOT)
+ /* adjtime() is independent from ntp_adjtime() */
+ time_adjust = txc->offset;
+ else
+ ntp_update_offset(txc->offset);
}
- else if (time_status & STA_PLL) {
- time_offset = txc->offset * NSEC_PER_USEC;
-
- /*
- * Scale the phase adjustment and
- * clamp to the operating range.
- */
- time_offset = min(time_offset, (s64)MAXPHASE * NSEC_PER_USEC);
- time_offset = max(time_offset, (s64)-MAXPHASE * NSEC_PER_USEC);
-
- /*
- * 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;
-
- freq_adj = time_offset * mtemp;
- freq_adj = shift_right(freq_adj, time_constant * 2 +
- (SHIFT_PLL + 2) * 2 - SHIFT_NSEC);
- if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC))
- freq_adj += div_s64(time_offset << (SHIFT_NSEC - SHIFT_FLL), mtemp);
- freq_adj += time_freq;
- freq_adj = min(freq_adj, (s64)MAXFREQ_NSEC);
- time_freq = max(freq_adj, (s64)-MAXFREQ_NSEC);
- time_offset = div_s64(time_offset, NTP_INTERVAL_FREQ);
- time_offset <<= SHIFT_UPDATE;
- } /* STA_PLL */
- } /* txc->modes & ADJ_OFFSET */
- if (txc->modes & ADJ_TICK)
- tick_usec = txc->tick;
-
- if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET))
- ntp_update_frequency();
- } /* txc->modes */
-leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0)
+ if (txc->modes & ADJ_TICK)
+ tick_usec = txc->tick;
+
+ if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET))
+ ntp_update_frequency();
+ }
+leave:
+ if (time_status & (STA_UNSYNC|STA_CLOCKERR))
result = TIME_ERROR;
if ((txc->modes == ADJ_OFFSET_SINGLESHOT) ||
- (txc->modes == ADJ_OFFSET_SS_READ))
+ (txc->modes == ADJ_OFFSET_SS_READ))
txc->offset = save_adjust;
else
txc->offset = ((long)shift_right(time_offset, SHIFT_UPDATE)) *
@@ -384,9 +390,12 @@ leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0)
txc->errcnt = 0;
txc->stbcnt = 0;
write_sequnlock_irq(&xtime_lock);
+
do_gettimeofday(&txc->time);
+
notify_cmos_timer();
- return(result);
+
+ return result;
}
static int __init ntp_tick_adj_setup(char *str)