With Alfred's permission, remove vm_mtx in favor of a fine-grained approach

(this commit is just the first stage).  Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.

1 files changed, 2 insertions, 3 deletions

diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index dd3eb04e157a..9eecbc28c1f9 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -209,6 +209,8 @@ fork1(p1, flags, procp)
 	struct forklist *ep;
 	struct filedesc *fd;
 
+	GIANT_REQUIRED;
+
 	/* Can't copy and clear */
 	if ((flags & (RFFDG|RFCFDG)) == (RFFDG|RFCFDG))
 		return (EINVAL);
@@ -218,9 +220,7 @@ fork1(p1, flags, procp)
 	 * certain parts of a process from itself.
 	 */
 	if ((flags & RFPROC) == 0) {
-
 		vm_fork(p1, 0, flags);
-		mtx_assert(&vm_mtx, MA_NOTOWNED);
 
 		/*
 		 * Close all file descriptors.
@@ -561,7 +561,6 @@ again:
 	 * execution path later.  (ie: directly into user mode)
 	 */
 	vm_fork(p1, p2, flags);
-	mtx_assert(&vm_mtx, MA_NOTOWNED);
 
 	if (flags == (RFFDG | RFPROC)) {
 		cnt.v_forks++;