Remove mpte optimization from pmap_enter_quick().

There is a race with the current locking scheme and removing
it should have no measurable performance impact.
This fixes page faults leading to panics in pmap_enter_quick_locked()
on amd64/i386.

Reviewed by: alc,jhb,peter,ps

11 files changed, 28 insertions, 47 deletions

diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index 9206f7d..44ed928 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -2356,15 +2356,13 @@ pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
  * but is *MUCH* faster than pmap_enter...
  */
 
-vm_page_t
-pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
-    vm_page_t mpte)
+void
+pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
 {
 
 	PMAP_LOCK(pmap);
-	mpte = pmap_enter_quick_locked(pmap, va, m, prot, mpte);
+	(void) pmap_enter_quick_locked(pmap, va, m, prot, NULL);
 	PMAP_UNLOCK(pmap);
-	return (mpte);
 }
 
 static vm_page_t
diff --git a/sys/arm/arm/pmap.c b/sys/arm/arm/pmap.c
index 2d03111..7ebc5ea 100644
--- a/sys/arm/arm/pmap.c
+++ b/sys/arm/arm/pmap.c
@@ -3572,16 +3572,14 @@ pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
  * but is *MUCH* faster than pmap_enter...
  */
 
-vm_page_t
-pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
-    vm_page_t mpte)
+void
+pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
 {
 
  	PMAP_LOCK(pmap);
 	pmap_enter_locked(pmap, va, m, prot & (VM_PROT_READ | VM_PROT_EXECUTE),
 	    FALSE);
  	PMAP_UNLOCK(pmap);
-	return (NULL);
 }
 
 /*
diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c
index 86afaee..63b5b7c 100644
--- a/sys/i386/i386/pmap.c
+++ b/sys/i386/i386/pmap.c
@@ -2432,15 +2432,13 @@ pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
  * but is *MUCH* faster than pmap_enter...
  */
 
-vm_page_t
-pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
-    vm_page_t mpte)
+void
+pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
 {
 
 	PMAP_LOCK(pmap);
-	mpte = pmap_enter_quick_locked(pmap, va, m, prot, mpte);
+	(void) pmap_enter_quick_locked(pmap, va, m, prot, NULL);
 	PMAP_UNLOCK(pmap);
-	return (mpte);
 }
 
 static vm_page_t
diff --git a/sys/ia64/ia64/pmap.c b/sys/ia64/ia64/pmap.c
index 0fa0d0e..155b0c7 100644
--- a/sys/ia64/ia64/pmap.c
+++ b/sys/ia64/ia64/pmap.c
@@ -1665,15 +1665,13 @@ pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
  * but is *MUCH* faster than pmap_enter...
  */
 
-vm_page_t
-pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
-    vm_page_t mpte)
+void
+pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
 {
 
 	PMAP_LOCK(pmap);
 	pmap_enter_quick_locked(pmap, va, m, prot);
 	PMAP_UNLOCK(pmap);
-	return (NULL);
 }
 
 static void
diff --git a/sys/powerpc/aim/mmu_oea.c b/sys/powerpc/aim/mmu_oea.c
index 23e8c4f..6a9af00 100644
--- a/sys/powerpc/aim/mmu_oea.c
+++ b/sys/powerpc/aim/mmu_oea.c
@@ -313,8 +313,7 @@ void moea_copy_page(mmu_t, vm_page_t, vm_page_t);
 void moea_enter(mmu_t, pmap_t, vm_offset_t, vm_page_t, vm_prot_t, boolean_t);
 void moea_enter_object(mmu_t, pmap_t, vm_offset_t, vm_offset_t, vm_page_t,
     vm_prot_t);
-vm_page_t moea_enter_quick(mmu_t, pmap_t, vm_offset_t, vm_page_t, vm_prot_t,
-    vm_page_t);
+void moea_enter_quick(mmu_t, pmap_t, vm_offset_t, vm_page_t, vm_prot_t);
 vm_paddr_t moea_extract(mmu_t, pmap_t, vm_offset_t);
 vm_page_t moea_extract_and_hold(mmu_t, pmap_t, vm_offset_t, vm_prot_t);
 void moea_init(mmu_t);
@@ -1174,16 +1173,16 @@ moea_enter_object(mmu_t mmu, pmap_t pm, vm_offset_t start, vm_offset_t end,
 	PMAP_UNLOCK(pm);
 }
 
-vm_page_t
+void
 moea_enter_quick(mmu_t mmu, pmap_t pm, vm_offset_t va, vm_page_t m,
-    vm_prot_t prot, vm_page_t mpte)
+    vm_prot_t prot)
 {
 
 	PMAP_LOCK(pm);
 	moea_enter_locked(pm, va, m, prot & (VM_PROT_READ | VM_PROT_EXECUTE),
 	    FALSE);
 	PMAP_UNLOCK(pm);
-	return (NULL);
+
 }
 
 vm_paddr_t
diff --git a/sys/powerpc/powerpc/mmu_if.m b/sys/powerpc/powerpc/mmu_if.m
index cd9a1d5..5fd0510 100644
--- a/sys/powerpc/powerpc/mmu_if.m
+++ b/sys/powerpc/powerpc/mmu_if.m
@@ -227,17 +227,13 @@ METHOD void enter_object {
  * @param _va		mapping virtual address
  * @param _pg		mapping physical page
  * @param _prot		new page protection - used to see if page is exec.
- * @param _mpte		???
- *
- * @retval NULL		(possibly a hint for future calls ?)
  */
-METHOD vm_page_t enter_quick {
+METHOD void enter_quick {
 	mmu_t		_mmu;
 	pmap_t		_pmap;
 	vm_offset_t	_va;
 	vm_page_t	_pg;
 	vm_prot_t	_prot;
-	vm_page_t	_mpte;
 };
 
 
diff --git a/sys/powerpc/powerpc/mmu_oea.c b/sys/powerpc/powerpc/mmu_oea.c
index 23e8c4f..6a9af00 100644
--- a/sys/powerpc/powerpc/mmu_oea.c
+++ b/sys/powerpc/powerpc/mmu_oea.c
@@ -313,8 +313,7 @@ void moea_copy_page(mmu_t, vm_page_t, vm_page_t);
 void moea_enter(mmu_t, pmap_t, vm_offset_t, vm_page_t, vm_prot_t, boolean_t);
 void moea_enter_object(mmu_t, pmap_t, vm_offset_t, vm_offset_t, vm_page_t,
     vm_prot_t);
-vm_page_t moea_enter_quick(mmu_t, pmap_t, vm_offset_t, vm_page_t, vm_prot_t,
-    vm_page_t);
+void moea_enter_quick(mmu_t, pmap_t, vm_offset_t, vm_page_t, vm_prot_t);
 vm_paddr_t moea_extract(mmu_t, pmap_t, vm_offset_t);
 vm_page_t moea_extract_and_hold(mmu_t, pmap_t, vm_offset_t, vm_prot_t);
 void moea_init(mmu_t);
@@ -1174,16 +1173,16 @@ moea_enter_object(mmu_t mmu, pmap_t pm, vm_offset_t start, vm_offset_t end,
 	PMAP_UNLOCK(pm);
 }
 
-vm_page_t
+void
 moea_enter_quick(mmu_t mmu, pmap_t pm, vm_offset_t va, vm_page_t m,
-    vm_prot_t prot, vm_page_t mpte)
+    vm_prot_t prot)
 {
 
 	PMAP_LOCK(pm);
 	moea_enter_locked(pm, va, m, prot & (VM_PROT_READ | VM_PROT_EXECUTE),
 	    FALSE);
 	PMAP_UNLOCK(pm);
-	return (NULL);
+
 }
 
 vm_paddr_t
diff --git a/sys/powerpc/powerpc/pmap_dispatch.c b/sys/powerpc/powerpc/pmap_dispatch.c
index d454af6..77f8368 100644
--- a/sys/powerpc/powerpc/pmap_dispatch.c
+++ b/sys/powerpc/powerpc/pmap_dispatch.c
@@ -122,11 +122,10 @@ pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
 	MMU_ENTER_OBJECT(mmu_obj, pmap, start, end, m_start, prot);
 }
 
-vm_page_t
-pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
-    vm_page_t mpte)
+void
+pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
 {
-	return (MMU_ENTER_QUICK(mmu_obj, pmap, va, m, prot, mpte));
+	MMU_ENTER_QUICK(mmu_obj, pmap, va, m, prot);
 }
 
 vm_paddr_t
diff --git a/sys/sparc64/sparc64/pmap.c b/sys/sparc64/sparc64/pmap.c
index 43dfbd5..200867b 100644
--- a/sys/sparc64/sparc64/pmap.c
+++ b/sys/sparc64/sparc64/pmap.c
@@ -1443,16 +1443,14 @@ pmap_enter_object(pmap_t pm, vm_offset_t start, vm_offset_t end,
 	PMAP_UNLOCK(pm);
 }
 
-vm_page_t
-pmap_enter_quick(pmap_t pm, vm_offset_t va, vm_page_t m, vm_prot_t prot,
-    vm_page_t mpte)
+void
+pmap_enter_quick(pmap_t pm, vm_offset_t va, vm_page_t m, vm_prot_t prot)
 {
 
 	PMAP_LOCK(pm);
 	pmap_enter_locked(pm, va, m, prot & (VM_PROT_READ | VM_PROT_EXECUTE),
 	    FALSE);
 	PMAP_UNLOCK(pm);
-	return (NULL);
 }
 
 void
diff --git a/sys/vm/pmap.h b/sys/vm/pmap.h
index 937fc71..57d62aa 100644
--- a/sys/vm/pmap.h
+++ b/sys/vm/pmap.h
@@ -97,8 +97,8 @@ void		 pmap_copy(pmap_t, pmap_t, vm_offset_t, vm_size_t, vm_offset_t);
 void		 pmap_copy_page(vm_page_t, vm_page_t);
 void		 pmap_enter(pmap_t, vm_offset_t, vm_page_t, vm_prot_t,
 		    boolean_t);
-vm_page_t	 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m,
-		    vm_prot_t prot, vm_page_t mpte);
+void	 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m,
+		    vm_prot_t prot);
 void		 pmap_enter_object(pmap_t pmap, vm_offset_t start,
 		    vm_offset_t end, vm_page_t m_start, vm_prot_t prot);
 vm_paddr_t	 pmap_extract(pmap_t pmap, vm_offset_t va);
diff --git a/sys/vm/vm_fault.c b/sys/vm/vm_fault.c
index 2484af1..9387575 100644
--- a/sys/vm/vm_fault.c
+++ b/sys/vm/vm_fault.c
@@ -953,7 +953,7 @@ vm_fault_prefault(pmap_t pmap, vm_offset_t addra, vm_map_entry_t entry)
 	int i;
 	vm_offset_t addr, starta;
 	vm_pindex_t pindex;
-	vm_page_t m, mpte;
+	vm_page_t m;
 	vm_object_t object;
 
 	if (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))
@@ -968,7 +968,6 @@ vm_fault_prefault(pmap_t pmap, vm_offset_t addra, vm_map_entry_t entry)
 		starta = 0;
 	}
 
-	mpte = NULL;
 	for (i = 0; i < PAGEORDER_SIZE; i++) {
 		vm_object_t backing_object, lobject;
 
@@ -1009,8 +1008,7 @@ vm_fault_prefault(pmap_t pmap, vm_offset_t addra, vm_map_entry_t entry)
 			vm_page_lock_queues();
 			if (VM_PAGE_INQUEUE1(m, PQ_CACHE))
 				vm_page_deactivate(m);
-			mpte = pmap_enter_quick(pmap, addr, m,
-			    entry->protection, mpte);
+			pmap_enter_quick(pmap, addr, m, entry->protection);
 			vm_page_unlock_queues();
 		}
 		VM_OBJECT_UNLOCK(lobject);