Major update to the way synchronization is done in the kernel. Highlights

include:

* Mutual exclusion is used instead of spl*().  See mutex(9).  (Note: The
  alpha port is still in transition and currently uses both.)

* Per-CPU idle processes.

* Interrupts are run in their own separate kernel threads and can be
  preempted (i386 only).

Partially contributed by:	BSDi (BSD/OS)
Submissions by (at least):	cp, dfr, dillon, grog, jake, jhb, sheldonh

1 files changed, 10 insertions, 1 deletions

diff --git a/sys/vm/vm_glue.c b/sys/vm/vm_glue.c
index 849a30affd60..ea39d7f1305c 100644
--- a/sys/vm/vm_glue.c
+++ b/sys/vm/vm_glue.c
@@ -74,9 +74,11 @@
 #include <sys/sysctl.h>
 
 #include <sys/kernel.h>
+#include <sys/ktr.h>
 #include <sys/unistd.h>
 
 #include <machine/limits.h>
+#include <machine/mutex.h>
 
 #include <vm/vm.h>
 #include <vm/vm_param.h>
@@ -316,8 +318,11 @@ faultin(p)
 
 		s = splhigh();
 
-		if (p->p_stat == SRUN)
+		if (p->p_stat == SRUN) {
+			mtx_enter(&sched_lock, MTX_SPIN);
 			setrunqueue(p);
+			mtx_exit(&sched_lock, MTX_SPIN);
+		}
 
 		p->p_flag |= P_INMEM;
 
@@ -332,6 +337,8 @@ faultin(p)
  * This swapin algorithm attempts to swap-in processes only if there
  * is enough space for them.  Of course, if a process waits for a long
  * time, it will be swapped in anyway.
+ *
+ * Giant is still held at this point, to be released in tsleep.
  */
 /* ARGSUSED*/
 static void
@@ -343,6 +350,8 @@ scheduler(dummy)
 	struct proc *pp;
 	int ppri;
 
+	mtx_assert(&Giant, MA_OWNED);
+
 loop:
 	if (vm_page_count_min()) {
 		VM_WAIT;