--- xinu/sys/resched.c	2018/04/24 17:39:03	1.1.1.1
+++ xinu/sys/resched.c	2018/04/24 17:39:31	1.1.1.2
@@ -10,7 +10,7 @@
  *
  * Notes:	Upon entry, currpid gives current process id.
  *		Proctab[currpid].pstate gives correct NEXT state for
- *			current process if other than PRCURR.
+ *			current process if other than PRREADY.
  *------------------------------------------------------------------------
  */
 int	resched()
@@ -21,8 +21,9 @@ int	resched()
 	/* no switch needed if current process priority higher than next*/
 
 	if ( ( (optr= &proctab[currpid])->pstate == PRCURR) &&
-	   (lastkey(rdytail)<optr->pprio))
+	   (lastkey(rdytail)<optr->pprio)) {
 		return(OK);
+	}
 
 	/* force context switch */
 
@@ -35,22 +36,12 @@ int	resched()
 
 	nptr = &proctab[ (currpid = getlast(rdytail)) ];
 	nptr->pstate = PRCURR;		/* mark it currently running	*/
-#ifdef	STKCHK
-	if ( *( (int *)nptr->pbase  ) != MAGIC ) {
-		kprintf("Bad magic pid=%d, value=%x, at %x\n",
-			currpid, *( (int *)nptr->pbase ), nptr->pbase);
-		panic("stack corrupted");
-	}
-	if ( ((unsigned)nptr->pregs[SPINDX]) < ((unsigned)nptr->plimit) ) {
-		kprintf("Bad SP pid=%d (%s), lim=%x will be %x\n",
-			currpid, nptr->pname, nptr->plimit,
-			nptr->pregs[SPINDX]);
-		panic("stack overflow");
-	}
-#endif
 #ifdef	RTCLOCK
 	preempt = QUANTUM;		/* reset preemption counter	*/
 #endif
-	ctxsw(nptr->pregs);
+	ctxsw(optr->pregs,nptr->pregs);
+
+	/* The OLD process returns here when resumed. */
+
 	return(OK);
 }