From ff13bc52ac8248043eabcaa4feac43afaf8e3f90 Mon Sep 17 00:00:00 2001
From: Venkatesh Srinivas <me@endeavour.zapto.org>
Date: Wed, 24 Nov 2010 12:40:40 -0800
Subject: [PATCH] kernel - Export vm_map_transition_wait and correct race
 between sleep/wakeup.

---
 sys/vm/vm_map.c | 5 +++--
 sys/vm/vm_map.h | 2 ++
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c
index c01e96d42a..4d8add2585 100644
--- a/sys/vm/vm_map.c
+++ b/sys/vm/vm_map.c
@@ -75,6 +75,7 @@
 #include <sys/systm.h>
 #include <sys/kernel.h>
 #include <sys/proc.h>
+#include <sys/serialize.h>
 #include <sys/lock.h>
 #include <sys/vmmeter.h>
 #include <sys/mman.h>
@@ -1418,12 +1419,12 @@ _vm_map_clip_end(vm_map_t map, vm_map_entry_t entry, vm_offset_t end,
  * Used to block when an in-transition collison occurs.  The map
  * is unlocked for the sleep and relocked before the return.
  */
-static
 void
 vm_map_transition_wait(vm_map_t map)
 {
+	tsleep_interlock(map, 0);
 	vm_map_unlock(map);
-	tsleep(map, 0, "vment", 0);
+	tsleep(map, PINTERLOCKED, "vment", 0);
 	vm_map_lock(map);
 }
 
diff --git a/sys/vm/vm_map.h b/sys/vm/vm_map.h
index 93c6a392b8..0fbcfe1705 100644
--- a/sys/vm/vm_map.h
+++ b/sys/vm/vm_map.h
@@ -529,6 +529,8 @@ int vm_map_growstack (struct proc *p, vm_offset_t addr);
 int vmspace_swap_count (struct vmspace *vmspace);
 int vmspace_anonymous_count (struct vmspace *vmspace);
 void vm_map_set_wired_quick(vm_map_t map, vm_offset_t addr, vm_size_t size, int *);
+void vm_map_transition_wait(vm_map_t map);
+
 
 #endif
 #endif				/* _VM_VM_MAP_H_ */
-- 
2.41.0