Back out the modification of vm_map locks from lockmgr to sx locks. The

best path forward now is likely to change the lockmgr locks to simple
sleep mutexes, then see if any extra contention it generates is greater
than removed overhead of managing local locking state information,
cost of extra calls into lockmgr, etc.

Additionally, making the vm_map lock a mutex and respecting it properly
will put us much closer to not needing Giant magic in vm.

1 files changed, 3 insertions, 1 deletions

diff --git a/sys/vm/vm_glue.c b/sys/vm/vm_glue.c
index 75bd9b42..efbe38a 100644
--- a/sys/vm/vm_glue.c
+++ b/sys/vm/vm_glue.c
@@ -560,7 +560,9 @@ retry:
 			 * data structures there is a
 			 * possible deadlock.
 			 */
-			if (vm_map_try_lock(&vm->vm_map)) {
+			if (lockmgr(&vm->vm_map.lock,
+					LK_EXCLUSIVE | LK_NOWAIT,
+					NULL, curthread)) {
 				vmspace_free(vm);
 				PROC_UNLOCK(p);
 				goto nextproc;