X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Ftime%2Fntp.c;h=e64efaf957e8485b4d233412a69fdf45a1225691;hb=b62c855938be50c13f3f2aa81fafe4a9ca2b6650;hp=eb12509e00bdd964fb2ed552aa8402a703f363ae;hpb=ef29498655b18d2bfd69048e20835d19333981ab;p=linux-2.6 diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index eb12509e00..e64efaf957 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -10,8 +10,11 @@ #include #include +#include #include - +#include +#include +#include #include #include @@ -32,7 +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 long 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) */ @@ -114,13 +117,7 @@ void second_overflow(void) 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"); } @@ -129,13 +126,7 @@ void second_overflow(void) 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"); } @@ -185,18 +176,70 @@ u64 current_tick_length(void) return tick_length; } +#ifdef CONFIG_GENERIC_CMOS_UPDATE + +/* Disable the cmos update - used by virtualization and embedded */ +int no_sync_cmos_clock __read_mostly; + +static void sync_cmos_clock(unsigned long dummy); + +static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0); + +static void sync_cmos_clock(unsigned long dummy) +{ + struct timespec now, next; + int fail = 1; + + /* + * If we have an externally synchronized Linux clock, then update + * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be + * called as close as possible to 500 ms before the new second starts. + * This code is run on a timer. If the clock is set, that timer + * may not expire at the correct time. Thus, we adjust... + */ + if (!ntp_synced()) + /* + * Not synced, exit, do not restart a timer (if one is + * running, let it run out). + */ + return; + + getnstimeofday(&now); + if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) + fail = update_persistent_clock(now); + + next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec; + if (next.tv_nsec <= 0) + next.tv_nsec += NSEC_PER_SEC; + + if (!fail) + next.tv_sec = 659; + else + next.tv_sec = 0; + + if (next.tv_nsec >= NSEC_PER_SEC) { + next.tv_sec++; + next.tv_nsec -= NSEC_PER_SEC; + } + mod_timer(&sync_cmos_timer, jiffies + timespec_to_jiffies(&next)); +} -void __attribute__ ((weak)) notify_arch_cmos_timer(void) +static void notify_cmos_timer(void) { - return; + if (!no_sync_cmos_clock) + mod_timer(&sync_cmos_timer, jiffies + 1); } +#else +static inline void notify_cmos_timer(void) { } +#endif + /* adjtimex mainly allows reading (and writing, if superuser) of * kernel time-keeping variables. used by xntpd. */ int do_adjtimex(struct timex *txc) { - long ltemp, mtemp, save_adjust; + long mtemp, save_adjust, rem; s64 freq_adj, temp64; int result; @@ -206,10 +249,12 @@ int do_adjtimex(struct timex *txc) /* Now we validate the data before disabling interrupts */ - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) + 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) + if (txc->modes != ADJ_OFFSET_SINGLESHOT && + txc->modes != ADJ_OFFSET_SS_READ) return -EINVAL; + } if (txc->modes != ADJ_OFFSET_SINGLESHOT && (txc->modes & ADJ_OFFSET)) /* adjustment Offset limited to +- .512 seconds */ @@ -277,14 +322,14 @@ int do_adjtimex(struct timex *txc) time_adjust = txc->offset; } else if (time_status & STA_PLL) { - ltemp = txc->offset * NSEC_PER_USEC; + time_offset = txc->offset * NSEC_PER_USEC; /* * Scale the phase adjustment and * clamp to the operating range. */ - time_offset = min(ltemp, MAXPHASE * NSEC_PER_USEC); - time_offset = max(time_offset, -MAXPHASE * NSEC_PER_USEC); + 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 @@ -297,11 +342,11 @@ int do_adjtimex(struct timex *txc) mtemp = xtime.tv_sec - time_reftime; time_reftime = xtime.tv_sec; - freq_adj = (s64)time_offset * mtemp; + 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)) { - temp64 = (s64)time_offset << (SHIFT_NSEC - SHIFT_FLL); + temp64 = time_offset << (SHIFT_NSEC - SHIFT_FLL); if (time_offset < 0) { temp64 = -temp64; do_div(temp64, mtemp); @@ -314,8 +359,10 @@ int do_adjtimex(struct timex *txc) freq_adj += time_freq; freq_adj = min(freq_adj, (s64)MAXFREQ_NSEC); time_freq = max(freq_adj, (s64)-MAXFREQ_NSEC); - time_offset = (time_offset / NTP_INTERVAL_FREQ) - << SHIFT_UPDATE; + time_offset = div_long_long_rem_signed(time_offset, + NTP_INTERVAL_FREQ, + &rem); + time_offset <<= SHIFT_UPDATE; } /* STA_PLL */ } /* txc->modes & ADJ_OFFSET */ if (txc->modes & ADJ_TICK) @@ -327,13 +374,14 @@ int do_adjtimex(struct timex *txc) leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0) result = TIME_ERROR; - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) - txc->offset = save_adjust; + if ((txc->modes == ADJ_OFFSET_SINGLESHOT) || + (txc->modes == ADJ_OFFSET_SS_READ)) + txc->offset = save_adjust; else - txc->offset = shift_right(time_offset, SHIFT_UPDATE) - * NTP_INTERVAL_FREQ / 1000; - txc->freq = (time_freq / NSEC_PER_USEC) - << (SHIFT_USEC - SHIFT_NSEC); + txc->offset = ((long)shift_right(time_offset, SHIFT_UPDATE)) * + NTP_INTERVAL_FREQ / 1000; + txc->freq = (time_freq / NSEC_PER_USEC) << + (SHIFT_USEC - SHIFT_NSEC); txc->maxerror = time_maxerror; txc->esterror = time_esterror; txc->status = time_status; @@ -353,6 +401,6 @@ leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0) txc->stbcnt = 0; write_sequnlock_irq(&xtime_lock); do_gettimeofday(&txc->time); - notify_arch_cmos_timer(); + notify_cmos_timer(); return(result); }