While splitting flags and pqflags might have been a good idea in theory

to separate locking, on most modern machines this is not enough
since operations on short types touch other short types that share the
same word in memory.

Merge pg_flags and pqflags again and now use atomic operations to change
the flags. Also bump wire_count to an int and pg_version might go
int as well, just for alignment.

tested by many, many. ok miod@

1 files changed, 20 insertions, 22 deletions

diff --git a/sys/uvm/uvm_page_i.h b/sys/uvm/uvm_page_i.h
index d9df6e18754..b993e652220 100644
--- a/sys/uvm/uvm_page_i.h
+++ b/sys/uvm/uvm_page_i.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_page_i.h,v 1.16 2007/04/04 17:44:45 art Exp $	*/
+/*	$OpenBSD: uvm_page_i.h,v 1.17 2007/04/13 18:57:49 art Exp $	*/
 /*	$NetBSD: uvm_page_i.h,v 1.14 2000/11/27 07:47:42 chs Exp $	*/
 
 /* 
@@ -151,17 +151,17 @@ PAGE_INLINE void
 uvm_pagewire(struct vm_page *pg)
 {
 	if (pg->wire_count == 0) {
-		if (pg->pqflags & PQ_ACTIVE) {
+		if (pg->pg_flags & PQ_ACTIVE) {
 			TAILQ_REMOVE(&uvm.page_active, pg, pageq);
-			pg->pqflags &= ~PQ_ACTIVE;
+			atomic_clearbits_int(&pg->pg_flags, PQ_ACTIVE);
 			uvmexp.active--;
 		}
-		if (pg->pqflags & PQ_INACTIVE) {
-			if (pg->pqflags & PQ_SWAPBACKED)
+		if (pg->pg_flags & PQ_INACTIVE) {
+			if (pg->pg_flags & PQ_SWAPBACKED)
 				TAILQ_REMOVE(&uvm.page_inactive_swp, pg, pageq);
 			else
 				TAILQ_REMOVE(&uvm.page_inactive_obj, pg, pageq);
-			pg->pqflags &= ~PQ_INACTIVE;
+			atomic_clearbits_int(&pg->pg_flags, PQ_INACTIVE);
 			uvmexp.inactive--;
 		}
 		uvmexp.wired++;
@@ -183,7 +183,7 @@ uvm_pageunwire(struct vm_page *pg)
 	if (pg->wire_count == 0) {
 		TAILQ_INSERT_TAIL(&uvm.page_active, pg, pageq);
 		uvmexp.active++;
-		pg->pqflags |= PQ_ACTIVE;
+		atomic_setbits_int(&pg->pg_flags, PQ_ACTIVE);
 		uvmexp.wired--;
 	}
 }
@@ -199,22 +199,20 @@ uvm_pageunwire(struct vm_page *pg)
 PAGE_INLINE void
 uvm_pagedeactivate(struct vm_page *pg)
 {
-	if (pg->pqflags & PQ_ACTIVE) {
+	if (pg->pg_flags & PQ_ACTIVE) {
 		TAILQ_REMOVE(&uvm.page_active, pg, pageq);
-		pg->pqflags &= ~PQ_ACTIVE;
+		atomic_clearbits_int(&pg->pg_flags, PQ_ACTIVE);
 		uvmexp.active--;
 	}
-	if ((pg->pqflags & PQ_INACTIVE) == 0) {
+	if ((pg->pg_flags & PQ_INACTIVE) == 0) {
 		KASSERT(pg->wire_count == 0);
-		if (pg->pqflags & PQ_SWAPBACKED)
+		if (pg->pg_flags & PQ_SWAPBACKED)
 			TAILQ_INSERT_TAIL(&uvm.page_inactive_swp, pg, pageq);
 		else
 			TAILQ_INSERT_TAIL(&uvm.page_inactive_obj, pg, pageq);
-		pg->pqflags |= PQ_INACTIVE;
+		atomic_setbits_int(&pg->pg_flags, PQ_INACTIVE);
 		uvmexp.inactive++;
-#ifndef UBC
 		pmap_clear_reference(pg);
-#endif
 		/*
 		 * update the "clean" bit.  this isn't 100%
 		 * accurate, and doesn't have to be.  we'll
@@ -223,7 +221,7 @@ uvm_pagedeactivate(struct vm_page *pg)
 		 */
 		if ((pg->pg_flags & PG_CLEAN) != 0 &&
 		    pmap_is_modified(pg))
-			pg->pg_flags &= ~PG_CLEAN;
+			atomic_clearbits_int(&pg->pg_flags, PG_CLEAN);
 	}
 }
 
@@ -236,12 +234,12 @@ uvm_pagedeactivate(struct vm_page *pg)
 PAGE_INLINE void
 uvm_pageactivate(struct vm_page *pg)
 {
-	if (pg->pqflags & PQ_INACTIVE) {
-		if (pg->pqflags & PQ_SWAPBACKED)
+	if (pg->pg_flags & PQ_INACTIVE) {
+		if (pg->pg_flags & PQ_SWAPBACKED)
 			TAILQ_REMOVE(&uvm.page_inactive_swp, pg, pageq);
 		else
 			TAILQ_REMOVE(&uvm.page_inactive_obj, pg, pageq);
-		pg->pqflags &= ~PQ_INACTIVE;
+		atomic_clearbits_int(&pg->pg_flags, PQ_INACTIVE);
 		uvmexp.inactive--;
 	}
 	if (pg->wire_count == 0) {
@@ -251,10 +249,10 @@ uvm_pageactivate(struct vm_page *pg)
 		 * can put it at tail.  if it wasn't active, then mark
 		 * it active and bump active count
 		 */
-		if (pg->pqflags & PQ_ACTIVE)
+		if (pg->pg_flags & PQ_ACTIVE)
 			TAILQ_REMOVE(&uvm.page_active, pg, pageq);
 		else {
-			pg->pqflags |= PQ_ACTIVE;
+			atomic_setbits_int(&pg->pg_flags, PQ_ACTIVE);
 			uvmexp.active++;
 		}
 
@@ -272,7 +270,7 @@ uvm_pageactivate(struct vm_page *pg)
 PAGE_INLINE void
 uvm_pagezero(struct vm_page *pg)
 {
-	pg->pg_flags &= ~PG_CLEAN;
+	atomic_clearbits_int(&pg->pg_flags, PG_CLEAN);
 	pmap_zero_page(pg);
 }
 
@@ -286,7 +284,7 @@ uvm_pagezero(struct vm_page *pg)
 PAGE_INLINE void
 uvm_pagecopy(struct vm_page *src, struct vm_page *dst)
 {
-	dst->pg_flags &= ~PG_CLEAN;
+	atomic_clearbits_int(&dst->pg_flags, PG_CLEAN);
 	pmap_copy_page(src, dst);
 }