diff options
Diffstat (limited to 'contrib/ntp/ntpd/ntp_loopfilter.c')
| -rw-r--r-- | contrib/ntp/ntpd/ntp_loopfilter.c | 651 |
1 files changed, 379 insertions, 272 deletions
diff --git a/contrib/ntp/ntpd/ntp_loopfilter.c b/contrib/ntp/ntpd/ntp_loopfilter.c index 15b625de6f20..c8a86cf12b66 100644 --- a/contrib/ntp/ntpd/ntp_loopfilter.c +++ b/contrib/ntp/ntpd/ntp_loopfilter.c @@ -6,19 +6,17 @@ # include <config.h> #endif +#include "ntpd.h" +#include "ntp_io.h" +#include "ntp_unixtime.h" +#include "ntp_stdlib.h" + #include <stdio.h> #include <ctype.h> -#include <sys/time.h> - #include <signal.h> #include <setjmp.h> -#include "ntpd.h" -#include "ntp_io.h" -#include "ntp_unixtime.h" -#include "ntp_stdlib.h" - #if defined(VMS) && defined(VMS_LOCALUNIT) /*wjm*/ #include "ntp_refclock.h" #endif /* VMS */ @@ -36,8 +34,9 @@ */ #define CLOCK_MAX .128 /* default max offset (s) */ #define CLOCK_PANIC 1000. /* default panic offset (s) */ -#define CLOCK_MAXSTAB 2e-6 /* max frequency stability */ +#define CLOCK_MAXSTAB 2e-6 /* max frequency stability (s/s) */ #define CLOCK_MAXERR 1e-2 /* max phase jitter (s) */ +#define CLOCK_PHI 15e-6 /* max frequency error (s/s) */ #define SHIFT_PLL 4 /* PLL loop gain (shift) */ #define CLOCK_AVG 4. /* FLL loop gain */ #define CLOCK_MINSEC 256. /* min FLL update interval (s) */ @@ -51,7 +50,26 @@ /* * Clock discipline state machine. This is used to control the * synchronization behavior during initialization and following a - * timewarp. + * timewarp. + * + * State < max > max Comments + * ==================================================== + * NSET FREQ FREQ no ntp.drift + * + * FSET TSET if (allow) TSET, ntp.drift + * else FREQ + * + * TSET SYNC FREQ time set + * + * FREQ SYNC if (mu < 900) FREQ calculate frequency + * else if (allow) TSET + * else FREQ + * + * SYNC SYNC if (mu < 900) SYNC normal state + * else SPIK + * + * SPIK SYNC if (allow) TSET spike detector + * else FREQ */ #define S_NSET 0 /* clock never set */ #define S_FSET 1 /* frequency set from the drift file */ @@ -72,10 +90,10 @@ * support is used as described above; if false, the kernel is bypassed * entirely and the daemon PLL used instead. * - * Each update to a prefer peer sets pps_update if it survives the + * Each update to a prefer peer sets pps_stratum if it survives the * intersection algorithm and its time is within range. The PPS time * discipline is enabled (STA_PPSTIME bit set in the status word) when - * pps_update is true and the PPS frequency discipline is enabled. If + * pps_stratum is true and the PPS frequency discipline is enabled. If * the PPS time discipline is enabled and the kernel reports a PPS * signal is present, the pps_control variable is set to the current * time. If the current time is later than pps_control by PPS_MAXAGE @@ -91,18 +109,27 @@ #define PPS_MAXAGE 120 /* kernel pps signal timeout (s) */ /* + * Program variables that can be tinkered. + */ +double clock_max = CLOCK_MAX; /* max offset before step (s) */ +double clock_panic = CLOCK_PANIC; /* max offset before panic (s) */ +double clock_phi = CLOCK_PHI; /* dispersion rate (s/s) */ +double clock_minstep = CLOCK_MINSTEP; /* step timeout (s) */ +double allan_xpt = CLOCK_ALLAN; /* minimum Allan intercept (s) */ + +/* * Program variables */ static double clock_offset; /* clock offset adjustment (s) */ -double drift_comp; /* clock frequency (ppm) */ -double clock_stability; /* clock stability (ppm) */ -double clock_max = CLOCK_MAX; /* max offset allowed before step (s) */ -static double clock_panic = CLOCK_PANIC; /* max offset allowed before panic */ +double drift_comp; /* clock frequency (s/s) */ +double clock_stability; /* clock stability (s/s) */ u_long pps_control; /* last pps sample time */ -static void rstclock P((int)); /* state transition function */ +static void rstclock P((int, double, double)); /* transition function */ #ifdef KERNEL_PLL -int pll_status; /* status bits for kernel pll */ +struct timex ntv; /* kernel API parameters */ +int pll_status; /* status bits for kernel pll */ +int pll_nano; /* nanosecond kernel switch */ #endif /* KERNEL_PLL */ /* @@ -111,32 +138,38 @@ int pll_status; /* status bits for kernel pll */ int ntp_enable; /* clock discipline enabled */ int pll_control; /* kernel support available */ int kern_enable; /* kernel support enabled */ +int pps_enable; /* kernel PPS discipline enabled */ int ext_enable; /* external clock enabled */ -int pps_update; /* pps update valid */ -int allow_set_backward = TRUE; /* step corrections allowed */ -int correct_any = FALSE; /* corrections > 1000 s allowed */ - -#ifdef STA_NANO -int pll_nano; /* nanosecond kernel switch */ -#endif /* STA_NANO */ +int pps_stratum; /* pps stratum */ +int allow_step = TRUE; /* allow step correction */ +int allow_panic = FALSE; /* allow panic correction */ +int mode_ntpdate = FALSE; /* exit on first clock set */ /* * Clock state machine variables */ -u_char sys_poll; /* log2 of system poll interval */ +u_char sys_minpoll = NTP_MINDPOLL; /* min sys poll interval (log2 s) */ +u_char sys_poll = NTP_MINDPOLL; /* system poll interval (log2 s) */ int state; /* clock discipline state */ int tc_counter; /* poll-adjust counter */ u_long last_time; /* time of last clock update (s) */ double last_offset; /* last clock offset (s) */ -double allan_xpt; /* Allan intercept (s) */ -double sys_error; /* system standard error (s) */ +double sys_jitter; /* system RMS jitter (s) */ + +/* + * Huff-n'-puff filter variables + */ +static double *sys_huffpuff; /* huff-n'-puff filter */ +static int sys_hufflen; /* huff-n'-puff filter stages */ +static int sys_huffptr; /* huff-n'-puff filter pointer */ +static double sys_mindly; /* huff-n'-puff filter min delay */ #if defined(KERNEL_PLL) /* Emacs cc-mode goes nuts if we split the next line... */ #define MOD_BITS (MOD_OFFSET | MOD_MAXERROR | MOD_ESTERROR | \ MOD_STATUS | MOD_TIMECONST) -static void pll_trap P((int)); /* configuration trap */ #ifdef SIGSYS +static void pll_trap P((int)); /* configuration trap */ static struct sigaction sigsys; /* current sigaction status */ static struct sigaction newsigsys; /* new sigaction status */ static sigjmp_buf env; /* environment var. for pll_trap() */ @@ -153,7 +186,7 @@ init_loopfilter(void) * Initialize state variables. Initially, we expect no drift * file, so set the state to S_NSET. */ - rstclock(S_NSET); + rstclock(S_NSET, current_time, 0); } /* @@ -175,30 +208,70 @@ local_clock( double dtemp, etemp; /* double temps */ int retval; /* return value */ -#if defined(KERNEL_PLL) - struct timex ntv; /* kernel interface structure */ -#endif /* KERNEL_PLL */ - + /* + * If the loop is opened, monitor and record the offsets + * anyway in order to determine the open-loop response. + */ #ifdef DEBUG if (debug) printf( - "local_clock: offset %.6f jitter %.6f state %d\n", - fp_offset, SQRT(epsil), state); + "local_clock: assocID %d off %.6f jit %.6f sta %d\n", + peer->associd, fp_offset, SQRT(epsil), state); #endif - if (!ntp_enable) - return(0); + if (!ntp_enable) { + record_loop_stats(fp_offset, drift_comp, SQRT(epsil), + clock_stability, sys_poll); + return (0); + } /* - * If the clock is way off, don't tempt fate by correcting it. + * If the clock is way off, panic is declared. The clock_panic + * defaults to 1000 s; if set to zero, the panic will never + * occur. The allow_panic defaults to FALSE, so the first panic + * will exit. It can be set TRUE by a command line option, in + * which case the clock will be set anyway and time marches on. + * But, allow_panic will be set it FALSE when the update is + * within the step range; so, subsequent panics will exit. */ -#ifndef SYS_WINNT - if (fabs(fp_offset) >= clock_panic && !correct_any) { + if (fabs(fp_offset) > clock_panic && clock_panic > 0 && + !allow_panic) { msyslog(LOG_ERR, - "time error %.0f over %d seconds; set clock manually", - fp_offset, (int)clock_panic); + "time correction of %.0f seconds exceeds sanity limit (%.0f); set clock manually to the correct UTC time.", + fp_offset, clock_panic); return (-1); } -#endif + + /* + * If simulating ntpdate, set the clock directly, rather than + * using the discipline. The clock_max defines the step + * threshold, above which the clock will be stepped instead of + * slewed. The value defaults to 128 ms, but can be set to even + * unreasonable values. If set to zero, the clock will never be + * stepped. + * + * Note that if ntpdate is active, the terminal does not detach, + * so the termination comments print directly to the console. + */ + if (mode_ntpdate) { + if (allow_step && fabs(fp_offset) > clock_max && + clock_max > 0) { + step_systime(fp_offset); + NLOG(NLOG_SYNCEVENT|NLOG_SYSEVENT) + msyslog(LOG_NOTICE, "time reset %.6f s", + fp_offset); + printf("ntpd: time reset %.6fs\n", fp_offset); + } else { + adj_systime(fp_offset); + NLOG(NLOG_SYNCEVENT|NLOG_SYSEVENT) + msyslog(LOG_NOTICE, "time slew %.6f s", + fp_offset); + printf("ntpd: time slew %.6fs\n", fp_offset); + } + record_loop_stats(fp_offset, drift_comp, SQRT(epsil), + clock_stability, sys_poll); + exit (0); + } + /* * If the clock has never been set, set it and initialize the * discipline parameters. We then switch to frequency mode to @@ -210,29 +283,60 @@ local_clock( step_systime(fp_offset); NLOG(NLOG_SYNCEVENT|NLOG_SYSEVENT) msyslog(LOG_NOTICE, "time set %.6f s", fp_offset); - rstclock(S_TSET); - rstclock(S_FREQ); + rstclock(S_FREQ, peer->epoch, fp_offset); return (1); } /* * Update the jitter estimate. */ - oerror = sys_error; - dtemp = SQUARE(sys_error); - sys_error = SQRT(dtemp + (epsil - dtemp) / CLOCK_AVG); + oerror = sys_jitter; + dtemp = SQUARE(sys_jitter); + sys_jitter = SQRT(dtemp + (epsil - dtemp) / CLOCK_AVG); + + /* + * The huff-n'-puff filter finds the lowest delay in the recent + * interval. This is used to correct the offset by one-half the + * difference between the sample delay and minimum delay. This + * is most effective if the delays are highly assymetric and + * clockhopping is avoided and the clock frequency wander is + * relatively small. + */ + if (sys_huffpuff != NULL) { + if (peer->delay < sys_huffpuff[sys_huffptr]) + sys_huffpuff[sys_huffptr] = peer->delay; + if (peer->delay < sys_mindly) + sys_mindly = peer->delay; + if (fp_offset > 0) + dtemp = -(peer->delay - sys_mindly) / 2; + else + dtemp = (peer->delay - sys_mindly) / 2; + fp_offset += dtemp; +#ifdef DEBUG + if (debug) + printf( + "local_clock: size %d mindly %.6f huffpuff %.6f\n", + sys_hufflen, sys_mindly, dtemp); +#endif + } /* * Clock state machine transition function. This is where the * action is and defines how the system reacts to large phase * and frequency errors. There are two main regimes: when the - * phase error exceeds the maximum allowed for ordinary tracking - * and otherwise when it does not. + * offset exceeds the step threshold and when it does not. + * However, if the step threshold is set to zero, a step will + * never occur. See the instruction manual for the details how + * these actions interact with the command line options. */ retval = 0; + if (sys_poll > peer->maxpoll) + sys_poll = peer->maxpoll; + else if (sys_poll < peer->minpoll) + sys_poll = peer->minpoll; clock_frequency = flladj = plladj = 0; - mu = current_time - last_time; - if (fabs(fp_offset) > clock_max) { + mu = peer->epoch - last_time; + if (fabs(fp_offset) > clock_max && clock_max > 0) { switch (state) { /* @@ -243,32 +347,29 @@ local_clock( * to S_FREQ state. */ case S_TSET: - rstclock(S_FREQ); - last_offset = clock_offset = fp_offset; - return (0); + state = S_FREQ; + break; /* * In S_SYNC state we ignore outlyers. At the first - * outlyer after CLOCK_MINSTEP (900 s), switch to S_SPIK + * outlyer after the stepout threshold, switch to S_SPIK * state. */ case S_SYNC: - if (mu < CLOCK_MINSTEP) + if (mu < clock_minstep) return (0); - rstclock(S_SPIK); + state = S_SPIK; return (0); /* * In S_FREQ state we ignore outlyers. At the first - * outlyer after CLOCK_MINSTEP (900 s), compute the - * apparent phase and frequency correction. + * outlyer after 900 s, compute the apparent phase and + * frequency correction. */ case S_FREQ: - if (mu < CLOCK_MINSTEP) + if (mu < clock_minstep) return (0); - clock_frequency = (fp_offset - clock_offset) / - mu; - /* fall through to default */ + /* fall through to S_SPIK */ /* * In S_SPIK state a large correction is necessary. @@ -286,19 +387,19 @@ local_clock( * reset or shaken, but never stirred. */ default: - if (allow_set_backward | correct_any) { + if (allow_step) { step_systime(fp_offset); NLOG(NLOG_SYNCEVENT|NLOG_SYSEVENT) msyslog(LOG_NOTICE, "time reset %.6f s", fp_offset); - rstclock(S_TSET); + rstclock(S_TSET, peer->epoch, 0); retval = 1; } else { NLOG(NLOG_SYNCEVENT|NLOG_SYSEVENT) msyslog(LOG_NOTICE, "time slew %.6f s", fp_offset); - rstclock(S_FREQ); - last_offset = clock_offset = fp_offset; + rstclock(S_FREQ, peer->epoch, + fp_offset); } break; } @@ -306,28 +407,25 @@ local_clock( switch (state) { /* - * If this is the first update, initialize the - * discipline parameters and pretend we had just set the - * clock. We don't want to step the clock unless we have - * to. + * In S_FSET state this is the first update. Adjust the + * phase, but don't adjust the frequency until the next + * update. */ case S_FSET: - rstclock(S_TSET); - last_offset = clock_offset = fp_offset; - return (0); + rstclock(S_TSET, peer->epoch, fp_offset); + break; /* - * In S_FREQ state we ignore updates until CLOCK_MINSTEP - * (900 s). After that, correct the phase and frequency - * and switch to S_SYNC state. + * In S_FREQ state ignore updates until the stepout + * threshold. After that, correct the phase and + * frequency and switch to S_SYNC state. */ case S_FREQ: - if (mu < CLOCK_MINSTEP) + if (mu < clock_minstep) return (0); clock_frequency = (fp_offset - clock_offset) / mu; - clock_offset = fp_offset; - rstclock(S_SYNC); + rstclock(S_SYNC, peer->epoch, fp_offset); break; /* @@ -337,7 +435,7 @@ local_clock( */ case S_TSET: case S_SPIK: - rstclock(S_SYNC); + state = S_SYNC; /* fall through to default */ /* @@ -349,14 +447,17 @@ local_clock( * and ignore it. */ default: + allow_panic = TRUE; if (fabs(fp_offset - last_offset) > CLOCK_SGATE * oerror && mu < ULOGTOD(sys_poll + 1)) { #ifdef DEBUG if (debug) printf( - "local_clock: popcorn %.6f %.6f\n", - fp_offset, last_offset); + "local_clock: popcorn %.6f %.6f\n", + fabs(fp_offset - + last_offset), CLOCK_SGATE * + oerror); #endif last_offset = fp_offset; return (0); @@ -366,29 +467,32 @@ local_clock( * Compute the FLL and PLL frequency adjustments * conditioned on intricate weighting factors. * For the FLL, the averaging interval is - * clamped not to decrease below the Allan - * intercept and the gain is decreased from - * unity for mu above CLOCK_MINSEC (1024 s) to - * zero below CLOCK_MINSEC (256 s). For the PLL, - * the averaging interval is clamped not to - * exceed the sustem poll interval. These - * measures insure stability of the clock - * discipline even when the rules of fair - * engagement are broken. + * clamped to a minimum of 1024 s and the gain + * is decreased from unity for mu above 1024 s + * to zero below 256 s. For the PLL, the + * averaging interval is clamped not to exceed + * the sustem poll interval. No gain factor is + * necessary, since the frequency steering above + * 1024 s is negligible. Particularly for the + * PLL, these measures allow oversampling, but + * not undersampling and insure stability even + * when the rules of fair engagement are broken. */ dtemp = max(mu, allan_xpt); etemp = min(max(0, mu - CLOCK_MINSEC) / - CLOCK_ALLAN, 1.); + allan_xpt, 1.); flladj = fp_offset * etemp / (dtemp * CLOCK_AVG); dtemp = ULOGTOD(SHIFT_PLL + 2 + sys_poll); etemp = min(mu, ULOGTOD(sys_poll)); plladj = fp_offset * etemp / (dtemp * dtemp); - clock_offset = fp_offset; + last_time = peer->epoch; + last_offset = clock_offset = fp_offset; break; } } +#if defined(KERNEL_PLL) /* * This code segment works when clock adjustments are made using * precision time kernel support and the ntp_adjtime() system @@ -399,7 +503,6 @@ local_clock( * modifications provide a true microsecond clock and nanosecond * clock, respectively. */ -#if defined(KERNEL_PLL) if (pll_control && kern_enable) { /* @@ -413,7 +516,7 @@ local_clock( * frequency offsets for jitter and stability values and * to update the drift file. */ - memset((char *)&ntv, 0, sizeof ntv); + memset(&ntv, 0, sizeof(ntv)); if (ext_enable) { ntv.modes = MOD_STATUS; } else { @@ -422,25 +525,21 @@ local_clock( dtemp = -.5; else dtemp = .5; -#ifdef STA_NANO - if (pll_nano) + if (pll_nano) { ntv.offset = (int32)(clock_offset * 1e9 + dtemp); - else -#endif /* STA_NANO */ + ntv.constant = sys_poll; + } else { ntv.offset = (int32)(clock_offset * 1e6 + dtemp); + ntv.constant = sys_poll - 4; + } if (clock_frequency != 0) { ntv.modes |= MOD_FREQUENCY; ntv.freq = (int32)((clock_frequency + drift_comp) * 65536e6); } -#ifdef STA_NANO - ntv.constant = sys_poll; -#else - ntv.constant = sys_poll - 4; -#endif /* STA_NANO */ - ntv.esterror = (u_int32)(sys_error * 1e6); + ntv.esterror = (u_int32)(sys_jitter * 1e6); ntv.maxerror = (u_int32)((sys_rootdelay / 2 + sys_rootdispersion) * 1e6); ntv.status = STA_PLL; @@ -467,63 +566,53 @@ local_clock( */ if (sys_poll > NTP_MAXDPOLL) ntv.status |= STA_FLL; - } - /* - * Wiggle the PPS bits according to the health of the - * prefer peer. - */ - if (pll_status & STA_PPSSIGNAL) - ntv.status |= STA_PPSFREQ; - if (pll_status & STA_PPSFREQ && pps_update) - ntv.status |= STA_PPSTIME; + /* + * If the PPS signal is up and enabled, light + * the frequency bit. If the PPS driver is + * working, light the phase bit as well. If not, + * douse the lights, since somebody else may + * have left the switch on. + */ + if (pps_enable && pll_status & STA_PPSSIGNAL) { + ntv.status |= STA_PPSFREQ; + if (pps_stratum < STRATUM_UNSPEC) + ntv.status |= STA_PPSTIME; + } else { + ntv.status &= ~(STA_PPSFREQ | + STA_PPSTIME); + } + } /* - * Update the offset and frequency from the kernel - * variables. + * Pass the stuff to the kernel. If it squeals, turn off + * the pigs. In any case, fetch the kernel offset and + * frequency and pretend we did it here. */ if (ntp_adjtime(&ntv) == TIME_ERROR) { if (ntv.status != pll_status) msyslog(LOG_ERR, - "kernel pll status change %x", + "kernel time discipline status change %x", ntv.status); + ntv.status &= ~(STA_PPSFREQ | STA_PPSTIME); } pll_status = ntv.status; -#ifdef STA_NANO if (pll_nano) clock_offset = ntv.offset / 1e9; else -#endif /* STA_NANO */ clock_offset = ntv.offset / 1e6; -#ifdef STA_NANO - sys_poll = ntv.constant; -#else - sys_poll = ntv.constant + 4; -#endif /* STA_NANO */ clock_frequency = ntv.freq / 65536e6 - drift_comp; flladj = plladj = 0; /* - * If the kernel pps discipline is working, monitor its - * performance. + * If the kernel PPS is lit, monitor its performance. */ if (ntv.status & STA_PPSTIME) { - if (!pps_control) - NLOG(NLOG_SYSEVENT)msyslog(LOG_INFO, - "pps sync enabled"); pps_control = current_time; -#ifdef STA_NANO if (pll_nano) - record_peer_stats( - &loopback_interface->sin, - ctlsysstatus(), ntv.offset / 1e9, - 0., ntv.jitter / 1e9, 0.); + sys_jitter = ntv.jitter / 1e9; else -#endif /* STA_NANO */ - record_peer_stats( - &loopback_interface->sin, - ctlsysstatus(), ntv.offset / 1e6, - 0., ntv.jitter / 1e6, 0.); + sys_jitter = ntv.jitter / 1e6; } } #endif /* KERNEL_PLL */ @@ -537,21 +626,26 @@ local_clock( */ etemp = clock_frequency + flladj + plladj; drift_comp += etemp; - if (drift_comp > sys_maxfreq) - drift_comp = sys_maxfreq; - else if (drift_comp <= -sys_maxfreq) - drift_comp = -sys_maxfreq; + if (drift_comp > NTP_MAXFREQ) + drift_comp = NTP_MAXFREQ; + else if (drift_comp <= -NTP_MAXFREQ) + drift_comp = -NTP_MAXFREQ; dtemp = SQUARE(clock_stability); etemp = SQUARE(etemp) - dtemp; clock_stability = SQRT(dtemp + etemp / CLOCK_AVG); - allan_xpt = max(CLOCK_ALLAN, clock_stability * CLOCK_ADF); /* - * In SYNC state, adjust the poll interval. + * In SYNC state, adjust the poll interval. The trick here is to + * compare the apparent frequency change induced by the system + * jitter over the poll interval, or fritter, to the frequency + * stability. If the fritter is greater than the stability, + * phase noise predominates and the averaging interval is + * increased; otherwise, it is decreased. A bit of hysteresis + * helps calm the dance. Works best using burst mode. */ if (state == S_SYNC) { - if (clock_stability < CLOCK_MAXSTAB && - fabs(clock_offset) < CLOCK_PGATE * sys_error) { + if (sys_jitter / ULOGTOD(sys_poll) > clock_stability && + fabs(clock_offset) < CLOCK_PGATE * sys_jitter) { tc_counter += sys_poll; if (tc_counter > CLOCK_LIMIT) { tc_counter = CLOCK_LIMIT; @@ -575,25 +669,17 @@ local_clock( /* * Update the system time variables. */ - last_time = current_time; - last_offset = clock_offset; - dtemp = peer->disp + SQRT(peer->variance + SQUARE(sys_error)); + dtemp = peer->disp + sys_jitter; if ((peer->flags & FLAG_REFCLOCK) == 0 && dtemp < MINDISPERSE) dtemp = MINDISPERSE; sys_rootdispersion = peer->rootdispersion + dtemp; - (void)record_loop_stats(); -#ifdef DEBUG - if (debug) - printf( - "local_clock: mu %.0f allan %.0f fadj %.3f fll %.3f pll %.3f\n", - mu, allan_xpt, clock_frequency * 1e6, flladj * 1e6, - plladj * 1e6); -#endif /* DEBUG */ + record_loop_stats(last_offset, drift_comp, sys_jitter, + clock_stability, sys_poll); #ifdef DEBUG if (debug) printf( - "local_clock: jitter %.6f freq %.3f stab %.3f poll %d count %d\n", - sys_error, drift_comp * 1e6, clock_stability * 1e6, + "local_clock: mu %.0f noi %.3f stb %.3f pol %d cnt %d\n", + mu, sys_jitter * 1e6 / mu, clock_stability * 1e6, sys_poll, tc_counter); #endif /* DEBUG */ return (retval); @@ -620,7 +706,7 @@ adj_host_clock( * maximum error and the local clock driver will pick it up and * pass to the common refclock routines. Very elegant. */ - sys_rootdispersion += CLOCK_PHI; + sys_rootdispersion += clock_phi; /* * Declare PPS kernel unsync if the pps signal has not been @@ -665,51 +751,35 @@ adj_host_clock( */ static void rstclock( - int trans /* new state */ + int trans, /* new state */ + double epoch, /* last time */ + double offset /* last offset */ ) { - correct_any = FALSE; + tc_counter = 0; + sys_poll = NTP_MINPOLL; state = trans; - switch (state) { - - /* - * Frequency mode. The clock has ben set, but the frequency has - * not yet been determined. Note that the Allan intercept is set - * insure the clock filter considers only the most recent - * measurements. - */ - case S_FREQ: - sys_poll = NTP_MINDPOLL; - allan_xpt = CLOCK_ALLAN; - last_time = current_time; - break; + last_time = epoch; + last_offset = clock_offset = offset; +} - /* - * Synchronized mode. Discipline the poll interval. - */ - case S_SYNC: - sys_poll = NTP_MINDPOLL; - allan_xpt = CLOCK_ALLAN; - tc_counter = 0; - break; - /* - * Don't do anything in S_SPIK state; just continue from S_SYNC - * state. - */ - case S_SPIK: - break; +/* + * huff-n'-puff filter + */ +void +huffpuff() +{ + int i; - /* - * S_NSET, S_FSET and S_TSET states. These transient states set - * the time reference for future frequency updates. - */ - default: - sys_poll = NTP_MINDPOLL; - allan_xpt = CLOCK_ALLAN; - last_time = current_time; - last_offset = clock_offset = 0; - break; + if (sys_huffpuff == NULL) + return; + sys_huffptr = (sys_huffptr + 1) % sys_hufflen; + sys_huffpuff[sys_huffptr] = 1e9; + sys_mindly = 1e9; + for (i = 0; i < sys_hufflen; i++) { + if (sys_huffpuff[i] < sys_mindly) + sys_mindly = sys_huffpuff[i]; } } @@ -723,111 +793,148 @@ loop_config( double freq ) { -#if defined(KERNEL_PLL) - struct timex ntv; -#endif /* KERNEL_PLL */ + int i; -#ifdef DEBUG - if (debug) - printf("loop_config: state %d freq %.3f\n", item, freq * - 1e6); -#endif switch (item) { - case LOOP_DRIFTINIT: - case LOOP_DRIFTCOMP: + case LOOP_DRIFTINIT: - /* - * The drift file is present and the initial frequency - * is available, so set the state to S_FSET - */ - rstclock(S_FSET); - drift_comp = freq; - if (drift_comp > sys_maxfreq) - drift_comp = sys_maxfreq; - if (drift_comp < -sys_maxfreq) - drift_comp = -sys_maxfreq; #ifdef KERNEL_PLL /* - * If the phase-lock code is implemented in the kernel, - * give the time_constant and saved frequency offset to - * the kernel. If not, no harm is done. Note the initial - * time constant is zero, but the first clock update - * will fix that. + * Assume the kernel supports the ntp_adjtime() syscall. + * If that syscall works, initialize the kernel + * variables. Otherwise, continue leaving no harm + * behind. While at it, ask to set nanosecond mode. If + * the kernel agrees, rejoice; othewise, it does only + * microseconds. */ - memset((char *)&ntv, 0, sizeof ntv); pll_control = 1; -#ifdef MOD_NANO - ntv.modes = MOD_NANO; -#endif /* MOD_NANO */ + memset(&ntv, 0, sizeof(ntv)); +#ifdef STA_NANO + ntv.modes = MOD_BITS | MOD_NANO; +#else + ntv.modes = MOD_BITS; +#endif /* STA_NANO */ + ntv.maxerror = MAXDISPERSE; + ntv.esterror = MAXDISPERSE; + ntv.status = STA_UNSYNC; #ifdef SIGSYS + /* + * Use sigsetjmp() to save state and then call + * ntp_adjtime(); if it fails, then siglongjmp() is used + * to return control + */ newsigsys.sa_handler = pll_trap; newsigsys.sa_flags = 0; if (sigaction(SIGSYS, &newsigsys, &sigsys)) { msyslog(LOG_ERR, "sigaction() fails to save SIGSYS trap: %m"); pll_control = 0; - return; } - - /* - * Use sigsetjmp() to save state and then call - * ntp_adjtime(); if it fails, then siglongjmp() is used - * to return control - */ if (sigsetjmp(env, 1) == 0) - (void)ntp_adjtime(&ntv); + ntp_adjtime(&ntv); if ((sigaction(SIGSYS, &sigsys, (struct sigaction *)NULL))) { msyslog(LOG_ERR, "sigaction() fails to restore SIGSYS trap: %m"); pll_control = 0; - return; } #else /* SIGSYS */ - if (ntp_adjtime(&ntv) < 0) { - msyslog(LOG_ERR, - "loop_config: ntp_adjtime() failed: %m"); - pll_control = 0; - } + ntp_adjtime(&ntv); #endif /* SIGSYS */ - - /* - * If the kernel support is available and enabled, - * initialize the parameters, but only if the external - * clock is not present. - */ - if (pll_control && kern_enable) { - msyslog(LOG_NOTICE, - "using kernel phase-lock loop %04x", - ntv.status); + pll_status = ntv.status; + if (pll_control) { #ifdef STA_NANO - if (ntv.status & STA_NANO) + if (pll_status & STA_NANO) pll_nano = 1; + if (pll_status & STA_CLK) + ext_enable = 1; #endif /* STA_NANO */ -#ifdef STA_CLK + msyslog(LOG_NOTICE, + "kernel time discipline status %04x", + pll_status); + } +#endif /* KERNEL_PLL */ + break; - if (ntv.status & STA_CLK) { - ext_enable = 1; - } else { - ntv.modes = MOD_BITS | MOD_FREQUENCY; + case LOOP_DRIFTCOMP: + + /* + * Initialize the kernel frequency and clamp to + * reasonable value. Also set the initial state to + * S_FSET to indicated the frequency has been + * initialized from the previously saved drift file. + */ + rstclock(S_FSET, current_time, 0); + drift_comp = freq; + if (drift_comp > NTP_MAXFREQ) + drift_comp = NTP_MAXFREQ; + if (drift_comp < -NTP_MAXFREQ) + drift_comp = -NTP_MAXFREQ; + +#ifdef KERNEL_PLL + /* + * Sanity check. If the kernel is enabled, load the + * frequency and light up the loop. If not, set the + * kernel frequency to zero and leave the loop dark. In + * either case set the time to zero to cancel any + * previous nonsense. + */ + if (pll_control) { + memset((char *)&ntv, 0, sizeof(ntv)); + ntv.modes = MOD_OFFSET | MOD_FREQUENCY; + if (kern_enable) { + ntv.modes |= MOD_STATUS; + ntv.status = STA_PLL; ntv.freq = (int32)(drift_comp * 65536e6); - ntv.maxerror = MAXDISPERSE; - ntv.esterror = MAXDISPERSE; - ntv.status = STA_UNSYNC | STA_PLL; - (void)ntp_adjtime(&ntv); } -#else - ntv.modes = MOD_BITS | MOD_FREQUENCY; - ntv.freq = (int32)(drift_comp * 65536e6); - ntv.maxerror = MAXDISPERSE; - ntv.esterror = MAXDISPERSE; - ntv.status = STA_UNSYNC | STA_PLL; (void)ntp_adjtime(&ntv); -#endif /* STA_CLK */ } #endif /* KERNEL_PLL */ + break; + + /* + * Special tinker variables for Ulrich Windl. Very dangerous. + */ + case LOOP_MAX: /* step threshold */ + clock_max = freq; + break; + + case LOOP_PANIC: /* panic exit threshold */ + clock_panic = freq; + break; + + case LOOP_PHI: /* dispersion rate */ + clock_phi = freq; + break; + + case LOOP_MINSTEP: /* watchdog bark */ + clock_minstep = freq; + break; + + case LOOP_MINPOLL: /* ephemeral association poll */ + if (freq < NTP_MINPOLL) + freq = NTP_MINPOLL; + sys_minpoll = (u_char)freq; + break; + + case LOOP_ALLAN: /* minimum Allan intercept */ + if (freq < CLOCK_ALLAN) + freq = CLOCK_ALLAN; + allan_xpt = freq; + break; + + case LOOP_HUFFPUFF: /* huff-n'-puff filter length */ + if (freq < HUFFPUFF) + freq = HUFFPUFF; + sys_hufflen = (int)(freq / HUFFPUFF); + sys_huffpuff = (double *)emalloc(sizeof(double) * + sys_hufflen); + for (i = 0; i < sys_hufflen; i++) + sys_huffpuff[i] = 1e9; + sys_mindly = 1e9; + break; } } |