1999/0227/port/tod.c (diff list | history)

1999/0225/sys/src/9/port/tod.c:102,110 – 1999/0227/sys/src/9/port/tod.c:102,110 (short | long | prev | next)
1999/0219		vlong last; // last reading of fast clock vlong off; // offset from epoch to last vlong lasttime; // last return value from gettod vlong delta; // amount to add to bias each slow clock tick int n; // number of times to add in delta int i; // number of times we've added in delta
1999/0227		vlong delta; // add 'delta' each slow clock tick from sstart to send ulong sstart; // ... ulong send; // ...
1999/0219		} tod; int
1999/0225/sys/src/9/port/tod.c:159,165 – 1999/0227/sys/src/9/port/tod.c:159,164
1999/0225		tod.multiplier = (TODFREQ<<tod.s1)/f; tod.maxdiff = 1LL<<(10 + lf);
1999/0219		iunlock(&tod);
1999/0225		//print("hz %lld mult %lld s1 %d s2 %d maxdiff %lld\n", tod.hz, tod.multiplier, tod.s1, tod.s2, tod.maxdiff);
1999/0219		} //
1999/0225/sys/src/9/port/tod.c:169,182 – 1999/0227/sys/src/9/port/tod.c:168,190
1999/0219		todset(vlong t, vlong delta, int n) { ilock(&tod); tod.i = tod.n = 0;
1999/0227		tod.sstart = tod.send = 0;
1999/0219		if(t >= 0){ tod.off = t; tod.last = fastticks(nil); tod.lasttime = 0; } else {
1999/0227		if(n <= 0) n = 1; n *= HZ; if(delta < 0 && n > -delta) n = -delta; if(delta > 0 && n > delta) n = delta; delta /= n; tod.sstart = MACHP(0)->ticks; tod.send = tod.sstart + n;
1999/0219		tod.delta = delta; tod.n = n; } iunlock(&tod); }
1999/0225/sys/src/9/port/tod.c:188,193 – 1999/0227/sys/src/9/port/tod.c:196,202
1999/0219		todget(void) { vlong ticks, x, diff;
1999/0227		ulong t;
1999/0219		ilock(&tod);
1999/0225/sys/src/9/port/tod.c:197,202 – 1999/0227/sys/src/9/port/tod.c:206,220
1999/0219		ticks = fastticks(nil); diff = ticks - tod.last;
1999/0227		// add in correction if(tod.sstart < tod.send){ t = MACHP(0)->ticks; if(t >= tod.send) t = tod.send; tod.off += tod.delta*(t - tod.sstart); tod.sstart = t; }
1999/0219		// convert to epoch
1999/0225		x = ((diff>>tod.s2)*tod.multiplier)>>(tod.s1-tod.s2);
1999/0219		x += tod.off;
1999/0225/sys/src/9/port/tod.c:222,236 – 1999/0227/sys/src/9/port/tod.c:240,245
1999/0219		void todfix(void) { if((MACHP(0)->ticks % HZ) != 0) return;
1999/0225		// once a second apply correction
1999/0219		ilock(&tod); if(tod.n > tod.i++) tod.off += tod.delta; iunlock(&tod);
1999/0225		// once a minute, make sure we don't overflow if((MACHP(0)->ticks % (60*HZ)) == 0) todget();