diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c
index 529b1542abc9..9e6fcecdbdb0 100644
--- a/sys/i386/i386/pmap.c
+++ b/sys/i386/i386/pmap.c
@@ -117,6 +117,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/sx.h>
 #include <sys/user.h>
 #include <sys/vmmeter.h>
+#include <sys/sched.h>
 #include <sys/sysctl.h>
 #ifdef SMP
 #include <sys/smp.h>
@@ -2340,38 +2341,6 @@ pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len,
 	}
 }	
 
-#ifdef SMP
-
-/*
- *	pmap_zpi_switchout*()
- *
- *	These functions allow us to avoid doing IPIs alltogether in certain
- *	temporary page-mapping situations (page zeroing).  Instead to deal
- *	with being preempted and moved onto a different cpu we invalidate
- *	the page when the scheduler switches us in.  This does not occur
- *	very often so we remain relatively optimal with very little effort.
- */
-static void
-pmap_zpi_switchout12(void)
-{
-	invlpg((u_int)CADDR1);
-	invlpg((u_int)CADDR2);
-}
-
-static void
-pmap_zpi_switchout2(void)
-{
-	invlpg((u_int)CADDR2);
-}
-
-static void
-pmap_zpi_switchout3(void)
-{
-	invlpg((u_int)CADDR3);
-}
-
-#endif
-
 static __inline void
 pagezero(void *page)
 {
@@ -2409,19 +2378,12 @@ pmap_zero_page(vm_page_t m)
 	mtx_lock(&CMAPCADDR12_lock);
 	if (*CMAP2)
 		panic("pmap_zero_page: CMAP2 busy");
-#ifdef SMP
-	curthread->td_pcb->pcb_switchout = pmap_zpi_switchout2;
-#endif
+	sched_pin();
 	*CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M;
-#ifdef SMP
-	invlpg((u_int)CADDR2);
-#endif
+	invlcaddr(CADDR2);
 	pagezero(CADDR2);
 	*CMAP2 = 0;
-	invlcaddr(CADDR2);
-#ifdef SMP
-	curthread->td_pcb->pcb_switchout = NULL;
-#endif
+	sched_unpin();
 	mtx_unlock(&CMAPCADDR12_lock);
 }
 
@@ -2438,22 +2400,15 @@ pmap_zero_page_area(vm_page_t m, int off, int size)
 	mtx_lock(&CMAPCADDR12_lock);
 	if (*CMAP2)
 		panic("pmap_zero_page: CMAP2 busy");
-#ifdef SMP
-	curthread->td_pcb->pcb_switchout = pmap_zpi_switchout2;
-#endif
+	sched_pin();
 	*CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M;
-#ifdef SMP
-	invlpg((u_int)CADDR2);
-#endif
+	invlcaddr(CADDR2);
 	if (off == 0 && size == PAGE_SIZE) 
 		pagezero(CADDR2);
 	else
 		bzero((char *)CADDR2 + off, size);
 	*CMAP2 = 0;
-	invlcaddr(CADDR2);
-#ifdef SMP
-	curthread->td_pcb->pcb_switchout = NULL;
-#endif
+	sched_unpin();
 	mtx_unlock(&CMAPCADDR12_lock);
 }
 
@@ -2469,19 +2424,12 @@ pmap_zero_page_idle(vm_page_t m)
 
 	if (*CMAP3)
 		panic("pmap_zero_page: CMAP3 busy");
-#ifdef SMP
-	curthread->td_pcb->pcb_switchout = pmap_zpi_switchout3;
-#endif
+	sched_pin();
 	*CMAP3 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M;
-#ifdef SMP
-	invlpg((u_int)CADDR3);
-#endif
+	invlcaddr(CADDR3);
 	pagezero(CADDR3);
 	*CMAP3 = 0;
-	invlcaddr(CADDR3);
-#ifdef SMP
-	curthread->td_pcb->pcb_switchout = NULL;
-#endif
+	sched_unpin();
 }
 
 /*
@@ -2499,27 +2447,19 @@ pmap_copy_page(vm_page_t src, vm_page_t dst)
 		panic("pmap_copy_page: CMAP1 busy");
 	if (*CMAP2)
 		panic("pmap_copy_page: CMAP2 busy");
-#ifdef SMP
-	curthread->td_pcb->pcb_switchout = pmap_zpi_switchout12;
-#endif
-	*CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A;
-	*CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M;
-#ifdef SMP
-	invlpg((u_int)CADDR1);
-	invlpg((u_int)CADDR2);
-#endif
-	bcopy(CADDR1, CADDR2, PAGE_SIZE);
-	*CMAP1 = 0;
-	*CMAP2 = 0;
+	sched_pin();
 #ifdef I386_CPU
 	invltlb();
 #else
 	invlpg((u_int)CADDR1);
 	invlpg((u_int)CADDR2);
 #endif
-#ifdef SMP
-	curthread->td_pcb->pcb_switchout = NULL;
-#endif
+	*CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A;
+	*CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M;
+	bcopy(CADDR1, CADDR2, PAGE_SIZE);
+	*CMAP1 = 0;
+	*CMAP2 = 0;
+	sched_unpin();
 	mtx_unlock(&CMAPCADDR12_lock);
 }