Index: vfs_subr.c
===================================================================
RCS file: /usr/cvs/src/sys/kern/vfs_subr.c,v
retrieving revision 1.687
diff -u -r1.687 vfs_subr.c
--- vfs_subr.c	31 Oct 2006 21:48:53 -0000	1.687
+++ vfs_subr.c	7 Nov 2006 18:33:22 -0000
@@ -1630,8 +1630,8 @@
 	EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc,
 	    SHUTDOWN_PRI_LAST);
 
+	mtx_lock(&sync_mtx);
 	for (;;) {
-		mtx_lock(&sync_mtx);
 		if (syncer_state == SYNCER_FINAL_DELAY &&
 		    syncer_final_iter == 0) {
 			mtx_unlock(&sync_mtx);
@@ -1696,7 +1696,6 @@
 		}
 		if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0)
 			syncer_final_iter--;
-		mtx_unlock(&sync_mtx);
 		/*
 		 * The variable rushjob allows the kernel to speed up the
 		 * processing of the filesystem syncer process. A rushjob
@@ -1707,13 +1706,10 @@
 		 * ahead of the disk that the kernel memory pool is being
 		 * threatened with exhaustion.
 		 */
-		mtx_lock(&sync_mtx);
 		if (rushjob > 0) {
 			rushjob -= 1;
-			mtx_unlock(&sync_mtx);
 			continue;
 		}
-		mtx_unlock(&sync_mtx);
 		/*
 		 * Just sleep for a short period if time between
 		 * iterations when shutting down to allow some I/O
@@ -1727,10 +1723,10 @@
 		 * filesystem activity.
 		 */
 		if (syncer_state != SYNCER_RUNNING)
-			tsleep(&dummychan, PPAUSE, "syncfnl",
+			msleep(&dummychan, &sync_mtx, PPAUSE, "syncfnl",
 			    hz / SYNCER_SHUTDOWN_SPEEDUP);
 		else if (time_uptime == starttime)
-			tsleep(&lbolt, PPAUSE, "syncer", 0);
+			msleep(&lbolt, &sync_mtx, PPAUSE, "syncer", 0);
 	}
 }