Index: kern/kern_exit.c
===================================================================
RCS file: /cvsroot/src/sys/kern/kern_exit.c,v
retrieving revision 1.262
diff -u -r1.262 kern_exit.c
--- kern/kern_exit.c	5 May 2005 06:42:02 -0000	1.262
+++ kern/kern_exit.c	19 May 2005 02:56:12 -0000
@@ -503,15 +503,7 @@
 	critical_enter();
 	mtx_unlock_spin(&sched_lock);
 	wakeup(p->p_pptr);
-	/*
-	 * XXX hack, swap in parent process, please see TDP_WAKEPROC0
-	 * code, because TDP_WAKEPROC0 is only useful if thread is
-	 * leaving critical region, but here we never leave and
-	 * thread_exit() will call cpu_throw(), TDP_WAKEPROC0 is never
-	 * cleared.
-	 */
-	if (p->p_pptr->p_sflag & PS_SWAPINREQ)
-		wakeup(&proc0);
+	
 	PROC_UNLOCK(p->p_pptr);
 	mtx_lock_spin(&sched_lock);
 	critical_exit();
Index: kern/kern_switch.c
===================================================================
RCS file: /cvsroot/src/sys/kern/kern_switch.c,v
retrieving revision 1.112
diff -u -r1.112 kern_switch.c
--- kern/kern_switch.c	19 May 2005 01:08:30 -0000	1.112
+++ kern/kern_switch.c	19 May 2005 02:56:12 -0000
@@ -593,15 +593,9 @@
 	td = curthread;
 	KASSERT(td->td_critnest != 0,
 	    ("critical_exit: td_critnest == 0"));
+#ifdef PREEMPTION
 	if (td->td_critnest == 1) {
-		if (td->td_pflags & TDP_WAKEPROC0) {
-			td->td_pflags &= ~TDP_WAKEPROC0;
-			wakeup(&proc0);
-		}
-		
 		td->td_critnest = 0;
-
-#ifdef PREEMPTION
 		mtx_assert(&sched_lock, MA_NOTOWNED);
 		if (td->td_owepreempt) {
 			td->td_critnest = 1;
@@ -610,12 +604,11 @@
 			mi_switch(SW_INVOL, NULL);
 			mtx_unlock_spin(&sched_lock);
 		}
-	             
+	} else 
 #endif
-
-	} else {
 		td->td_critnest--;
-	}
+	
+	
 	CTR4(KTR_CRITICAL, "critical_exit by thread %p (%ld, %s) to %d", td,
 	    (long)td->td_proc->p_pid, td->td_proc->p_comm, td->td_critnest);
 }
Index: kern/kern_synch.c
===================================================================
RCS file: /cvsroot/src/sys/kern/kern_synch.c,v
retrieving revision 1.269
diff -u -r1.269 kern_synch.c
--- kern/kern_synch.c	8 Apr 2005 03:37:53 -0000	1.269
+++ kern/kern_synch.c	19 May 2005 02:56:12 -0000
@@ -410,11 +410,10 @@
 			p->p_sflag |= PS_SWAPINREQ;
 			/*
 			 * due to a LOR between sched_lock and
-			 * the sleepqueue chain locks, delay
-			 * wakeup proc0 until thread leaves
-			 * critical region.
+			 * the sleepqueue chain locks, use
+			 * lower level scheduling functions.
 			 */
-			curthread->td_pflags |= TDP_WAKEPROC0;
+			kick_proc0();
 		}
 	} else
 		sched_wakeup(td);
Index: sys/proc.h
===================================================================
RCS file: /cvsroot/src/sys/sys/proc.h,v
retrieving revision 1.428
diff -u -r1.428 proc.h
--- sys/proc.h	23 Apr 2005 02:32:32 -0000	1.428
+++ sys/proc.h	19 May 2005 02:56:18 -0000
@@ -370,7 +370,7 @@
 #define	TDP_SA		0x00000080 /* A scheduler activation based thread. */
 #define	TDP_UNUSED8	0x00000100 /* --available -- */
 #define	TDP_OWEUPC	0x00000200 /* Call addupc() at next AST. */
-#define	TDP_WAKEPROC0	0x00000400 /* Wants caller to wakeup(&proc0) */
+#define	TDP_UNUSED10	0x00000400 /* --available -- */
 #define	TDP_CAN_UNBIND	0x00000800 /* Only temporarily bound. */
 #define	TDP_SCHED1	0x00001000 /* Reserved for scheduler private use */
 #define	TDP_SCHED2	0x00002000 /* Reserved for scheduler private use */
@@ -848,6 +848,7 @@
 	    struct trapframe *);
 void	fork_return(struct thread *, struct trapframe *);
 int	inferior(struct proc *p);
+void 	kick_proc0(void);
 int	leavepgrp(struct proc *p);
 int	maybe_preempt(struct thread *td);
 void	mi_switch(int flags, struct thread *newtd);
Index: vm/vm_glue.c
===================================================================
RCS file: /cvsroot/src/sys/vm/vm_glue.c,v
retrieving revision 1.210
diff -u -r1.210 vm_glue.c
--- vm/vm_glue.c	22 Jan 2005 19:21:29 -0000	1.210
+++ vm/vm_glue.c	19 May 2005 02:56:18 -0000
@@ -113,6 +113,10 @@
 static void swapout(struct proc *);
 #endif
 
+
+static volatile int proc0_rescan;
+
+
 /*
  * MPSAFE
  *
@@ -578,7 +582,8 @@
  *
  *  XXXKSE - process with the thread with highest priority counts..
  *
- * Giant is still held at this point, to be released in tsleep.
+ * Giant is still held at this point.
+ * ups: Do we still need Giant here?
  */
 /* ARGSUSED*/
 static void
@@ -597,6 +602,9 @@
 loop:
 	if (vm_page_count_min()) {
 		VM_WAIT;
+		mtx_lock_spin(&sched_lock);
+		proc0_rescan = 0;
+		mtx_unlock_spin(&sched_lock);
 		goto loop;
 	}
 
@@ -642,7 +650,15 @@
 	 * Nothing to do, back to sleep.
 	 */
 	if ((p = pp) == NULL) {
-		tsleep(&proc0, PVM, "sched", maxslp * hz / 2);
+		mtx_unlock(&Giant);
+		mtx_lock_spin(&sched_lock);
+		if (!proc0_rescan) {
+			TD_SET_IWAIT(&thread0);
+			mi_switch(SW_VOL, NULL);
+		}
+		proc0_rescan = 0;
+		mtx_unlock_spin(&sched_lock);
+		mtx_lock(&Giant);
 		goto loop;
 	}
 	PROC_LOCK(p);
@@ -654,6 +670,9 @@
 	 */
 	if (p->p_sflag & (PS_INMEM | PS_SWAPPINGOUT | PS_SWAPPINGIN)) {
 		PROC_UNLOCK(p);
+		mtx_lock_spin(&sched_lock);
+		proc0_rescan = 0;
+		mtx_unlock_spin(&sched_lock);
 		goto loop;
 	}
 
@@ -669,9 +688,28 @@
 	PROC_UNLOCK(p);
 	mtx_lock_spin(&sched_lock);
 	p->p_swtime = 0;
+	proc0_rescan = 0;
 	mtx_unlock_spin(&sched_lock);
 	goto loop;
 }
+
+void kick_proc0(void)
+{
+	struct thread *td = &thread0;
+
+		
+	if (TD_AWAITING_INTR(td)) {
+		CTR2(KTR_INTR, "%s: setrunqueue %d", __func__, 0);
+		TD_CLR_IWAIT(td);
+		setrunqueue(td, SRQ_INTR);
+	} else {
+		proc0_rescan = 1;
+		CTR2(KTR_INTR, "%s: state %d",
+		    __func__, td->td_state);
+	}
+	
+}
+
 
 #ifndef NO_SWAPPING