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, 5 insertions, 5 deletions

diff --git a/sys/uvm/uvm_km.c b/sys/uvm/uvm_km.c
index 4273e866a72..aa6f73fc8a5 100644
--- a/sys/uvm/uvm_km.c
+++ b/sys/uvm/uvm_km.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_km.c,v 1.57 2007/04/11 12:10:42 art Exp $	*/
+/*	$OpenBSD: uvm_km.c,v 1.58 2007/04/13 18:57:49 art Exp $	*/
 /*	$NetBSD: uvm_km.c,v 1.42 2001/01/14 02:10:01 thorpej Exp $	*/
 
 /* 
@@ -283,7 +283,7 @@ uvm_km_pgremove(struct uvm_object *uobj, vaddr_t start, vaddr_t end)
 
 		if (pp->pg_flags & PG_BUSY) {
 			/* owner must check for this when done */
-			pp->pg_flags |= PG_RELEASED;
+			atomic_setbits_int(&pp->pg_flags, PG_RELEASED);
 		} else {
 			/* free the swap slot... */
 			uao_dropswap(uobj, curoff >> PAGE_SHIFT);
@@ -404,7 +404,7 @@ uvm_km_kmemalloc(map, obj, size, flags)
 	while (size) {
 		pg = uvm_pagealloc(obj, offset, NULL, 0);
 		if (pg) {
-			pg->pg_flags &= ~PG_BUSY;	/* new page */
+			atomic_clearbits_int(&pg->pg_flags, PG_BUSY);
 			UVM_PAGE_OWN(pg, NULL);
 		}
 		
@@ -532,7 +532,7 @@ uvm_km_alloc1(struct vm_map *map, vsize_t size, vsize_t align, boolean_t zeroit)
 		if (pg) {
 			if ((pg->pg_flags & PG_RELEASED) == 0)
 				panic("uvm_km_alloc1: non-released page");
-			pg->pg_flags |= PG_WANTED;
+			atomic_setbits_int(&pg->pg_flags, PG_WANTED);
 			UVM_UNLOCK_AND_WAIT(pg, &uvm.kernel_object->vmobjlock,
 			    FALSE, "km_alloc", 0);
 			continue;   /* retry */
@@ -541,7 +541,7 @@ uvm_km_alloc1(struct vm_map *map, vsize_t size, vsize_t align, boolean_t zeroit)
 		/* allocate ram */
 		pg = uvm_pagealloc(uvm.kernel_object, offset, NULL, 0);
 		if (pg) {
-			pg->pg_flags &= ~PG_BUSY;	/* new page */
+			atomic_clearbits_int(&pg->pg_flags, PG_BUSY);
 			UVM_PAGE_OWN(pg, NULL);
 		}
 		simple_unlock(&uvm.kernel_object->vmobjlock);