diff options
Diffstat (limited to 'sys/kern/kern_clock.c')
| -rw-r--r-- | sys/kern/kern_clock.c | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/sys/kern/kern_clock.c b/sys/kern/kern_clock.c index 9e6d64e..7992995 100644 --- a/sys/kern/kern_clock.c +++ b/sys/kern/kern_clock.c @@ -39,7 +39,7 @@ static volatile int print_tci = 1; * SUCH DAMAGE. * * @(#)kern_clock.c 8.5 (Berkeley) 1/21/94 - * $Id: kern_clock.c,v 1.73 1998/06/09 13:10:52 phk Exp $ + * $Id: kern_clock.c,v 1.74 1998/07/02 21:35:02 phk Exp $ */ #include <sys/param.h> @@ -747,15 +747,14 @@ switch_timecounter(struct timecounter *newtc) static struct timecounter * sync_other_counter(void) { - struct timecounter *tc, *tco; + struct timecounter *tc, *tcn, *tco; unsigned delta; - if (timecounter->tc_poll_pps) - timecounter->tc_poll_pps(timecounter); - tc = timecounter->tc_other; - tco = tc->tc_other; - *tc = *timecounter; - tc->tc_other = tco; + tco = timecounter; + tc = tco->tc_other; + tcn = tc->tc_other; + *tc = *tco; + tc->tc_other = tcn; delta = tco_delta(tc); tc->tc_offset_count += delta; tc->tc_offset_count &= tc->tc_counter_mask; @@ -770,6 +769,17 @@ tco_forward(void) struct timecounter *tc; tc = sync_other_counter(); + /* + * We may be inducing a tiny error here, the tc_poll_pps() may + * process a latched count which happens after the tco_delta() + * in sync_other_counter(), which would extend the previous + * counters parameters into the domain of this new one. + * Since the timewindow is very small for this, the error is + * going to be only a few weenieseconds (as Dave Mills would + * say), so lets just not talk more about it, OK ? + */ + if (tc->tc_poll_pps) + tc->tc_poll_pps(tc); if (timedelta != 0) { tc->tc_offset_nano += (u_int64_t)(tickdelta * 1000) << 32; timedelta -= tickdelta; |
