diff options
| -rw-r--r-- | sys/kern/kern_tc.c | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/sys/kern/kern_tc.c b/sys/kern/kern_tc.c index 29d2f74..167ba20 100644 --- a/sys/kern/kern_tc.c +++ b/sys/kern/kern_tc.c @@ -21,6 +21,14 @@ __FBSDID("$FreeBSD$"); #include <sys/timex.h> /* + * a large step happens on boot. This constant detects such + * a steps. It is relatively small so that ntp_update_second gets called + * enough in the typical 'missed a couple of seconds' case, but doesn't + * loop forever when the time step is large. + */ +#define LARGE_STEP 200 + +/* * Implement a dummy timecounter which we can use until we get a real one * in the air. This allows the console and other early stuff to use * time services. @@ -344,6 +352,7 @@ tc_windup(void) u_int64_t scale; u_int delta, ncount, ogen; int i; + time_t t; /* * Make the next timehands a copy of the current one, but do not @@ -381,13 +390,28 @@ tc_windup(void) if (tho->th_counter->tc_poll_pps) tho->th_counter->tc_poll_pps(tho->th_counter); + /* + * Compute the UTC time, before any leapsecond adjustments, are + * made. + */ + bt = th->th_offset; + bintime_add(&bt, &boottimebin); + /* * Deal with NTP second processing. The for loop normally only * iterates once, but in extreme situations it might keep NTP sane - * if timeouts are not run for several seconds. + * if timeouts are not run for several seconds. At boot, the + * time step can be large when the TOD hardware has been read, so + * on really large steps, we call ntp_update_second only once. */ - for (i = th->th_offset.sec - tho->th_offset.sec; i > 0; i--) - ntp_update_second(&th->th_adjustment, &th->th_offset.sec); + for (i = bt.sec - tho->th_microtime.tv_sec; i > 0; i--) { + t = bt.sec; + ntp_update_second(&th->th_adjustment, &bt.sec); + if (bt.sec != t) + boottimebin.sec += bt.sec - t; + if (i > LARGE_STEP) + break; + } /* Now is a good time to change timecounters. */ if (th->th_counter != timecounter) { @@ -423,9 +447,6 @@ tc_windup(void) scale /= th->th_counter->tc_frequency; th->th_scale = scale * 2; - /* Update the UTC timestamps used for the get*() functions. */ - bt = th->th_offset; - bintime_add(&bt, &boottimebin); bintime2timeval(&bt, &th->th_microtime); bintime2timespec(&bt, &th->th_nanotime); |
