replay cleanup from Dave Mills

bk: 463f02d6CiWBvOc2tXoKfOmFD8awdA

diff --git a/ntpd/ntp_proto.c b/ntpd/ntp_proto.c
index 5976ecc97449bd16fa6de92e4bbd4b539499907f..1ab9200a2cafde5dc62dce61143cad5164d1edea 100644 (file)
--- a/ntpd/ntp_proto.c
+++ b/ntpd/ntp_proto.c
@@ -938,6 +938,8 @@ receive(
                        peer->flash |= TEST3;   /* protocol unsynch */
                else if (!L_ISEQU(&p_org, &peer->xmt))
                        peer->flash |= TEST2;   /* bogus packet */
+               else
+                       L_CLR(&peer->org);      /* avoid replay */
        }
 
        /*
@@ -3102,18 +3104,12 @@ peer_unfit(
 #define MINLOOPS 5             /* minimum number of step samples */
 
 /*
- * This routine calculates the system precision, defined as the minimum
- * of a sequence of differences between successive readings of the
- * system clock. However, if the system clock can be read more than once
- * during a tick interval, the difference can be zero or one LSB unit,
- * where the LSB corresponds to one nanosecond or one microsecond.
- * Conceivably, if some other process preempts this one and reads the
- * clock, the difference can be more than one LSB unit.
- *
- * For hardware clock frequencies of 10 MHz or less, we assume the
- * logical clock advances only at the hardware clock tick. For higher
- * frequencies, we assume the logical clock can advance no more than 100
- * nanoseconds between ticks.
+ * This routine measures the system precision defined as the minimum of
+ * a sequence of differences between successive readings of the system
+ * clock. However, if a difference is less than MINSTEP, the clock has
+ * been read more than once during a clock tick and the difference is
+ * ignored. We set MINSTEP greater than zero in case something happens
+ * like a cache miss.
  */
 int
 default_get_precision(void)
@@ -3126,13 +3122,12 @@ default_get_precision(void)
        int     i;              /* log2 precision */
 
        /*
-        * Loop to find tick value in nanoseconds. Toss out outlyer
-        * values less than the minimun tick value. In wacky cases, use
-        * the default maximum value.
+        * Loop to find precision value in seconds.
         */
-       get_systime(&last);
        tick = MAXSTEP;
-       for (i = 0; i < MINLOOPS;) {
+       i = 0;
+       get_systime(&last);
+       while (1) {
                get_systime(&val);
                diff = val;
                L_SUB(&diff, &last);
@@ -3140,9 +3135,11 @@ default_get_precision(void)
                LFPTOD(&diff, dtemp);
                if (dtemp < MINSTEP)
                        continue;
-               i++;
+
                if (dtemp < tick)
                        tick = dtemp;
+               if (++i >= MINLOOPS)
+                       break;
        }
 
        /*