3 files changed, 13 insertions(+), 15 deletions(-)

M pc/i8253.c
M pc/trap.c
M port/edf.c

@@ 188,6 188,8 @@ guesscpuhz(int aalcycles)
 ulong i8253periodset;
 int i8253dotimerset = 1;
 
+ulong phist[128];
+
 void
 i8253timerset(uvlong next)
 {


@@ 212,11 214,13 @@ i8253timerset(uvlong next)
 
 	/* hysteresis */
 	if(i8253.period != period){
+memmove(&phist[0], &phist[1], sizeof(phist)-sizeof(ulong));
+phist[nelem(phist)-1] = period;
 		ilock(&i8253);
 		/* load new value */
 		outb(Tmode, Load0|Square);
 		outb(T0cntr, period);		/* low byte */
-		outb(T0cntr, period>>8);	/* high byte */
+		outb(T0cntr, period>>8);		/* high byte */
 
 		/* remember period */
 		i8253.period = period;

@@ 265,8 265,10 @@ intrtime(Mach*, int vno)
 		m->perf.inidle -= diff;
 
 	diff /= m->cpumhz;
-	if(diff >= Ntimevec)
+	if(diff >= Ntimevec){
+		if (vno == 32) print("timer took %d µs\n", diff);
 		diff = Ntimevec-1;
+	}
 	intrtimes[vno][diff]++;
 }
 

@@ 213,8 213,6 @@ edfreleasetimer(void)
 	if ((t = qwaitrelease.head) == nil)
 		return;
 	DPRINT("edfreleasetimer clock\n");
-	if (releasetimer[m->machno].when)
-		timerdel(&releasetimer[m->machno]);
 	releasetimer[m->machno].when = t->r;
 	if (releasetimer[m->machno].when <= now)
 		releasetimer[m->machno].when = now;


@@ 356,8 354,6 @@ edfadmit(Task *t)
 		}
 		assert(t->runq.n > 0 || (up && up->task == t));
 		edfpush(t);
-		if (deadlinetimer[m->machno].when)
-			timerdel(&deadlinetimer[m->machno]);
 		deadlinetimer[m->machno].when = t->d;
 		timeradd(&deadlinetimer[m->machno]);
 	}else{


@@ 478,6 474,8 @@ edfdeadlineintr(Ureg*, Timer *timer)
 		now = fastticks(nil);
 
 		t = up->task;
+
+		assert(t->state == EdfRunning);
 		assert(t->scheduled > 0);
 	
 		used = now - t->scheduled;


@@ 806,12 804,9 @@ runt:
 		DPRINT("%d edftimer: %T too late\n", m->machno, ticks2time(now-when));
 		when = now;
 	}
-	if (deadlinetimer[m->machno].when){
-		if(deadlinetimer[m->machno].when == when){
-			iunlock(&edflock);
-			return p;
-		}
-		timerdel(&deadlinetimer[m->machno]);
+	if(deadlinetimer[m->machno].when == when){
+		iunlock(&edflock);
+		return p;
 	}
 	deadlinetimer[m->machno].when = when;
 	timeradd(&deadlinetimer[m->machno]);


@@ 1081,7 1076,6 @@ resacquire(Task *t, CSN *c)
 		t->curcsn->S -= used;
 	when = now + c->S;
 	if (when < deadlinetimer[m->machno].when){
-		timerdel(&deadlinetimer[m->machno]);
 		deadlinetimer[m->machno].when = when;
 		timeradd(&deadlinetimer[m->machno]);
 	}


@@ 1119,8 1113,6 @@ resrelease(Task *t)
 		t->Delta = Infinity;
 	c->S = 0LL;	/* don't allow reuse */
 	if(devrt) devrt(t, now, SResrel);
-	if (deadlinetimer[m->machno].when)
-		timerdel(&deadlinetimer[m->machno]);
 	deadlinetimer[m->machno].when = when;
 	timeradd(&deadlinetimer[m->machno]);