svn commit: r193556 - head/sys/fs/pseudofs

[Dag-Erling Smorgrav]

Author: des
Date: Sat Jun  6 00:44:13 2009
New Revision: 193556
URL: http://svn.freebsd.org/changeset/base/193556

Log:
  Drop Giant.
  
  MFC after:	1 week

Modified:
  head/sys/fs/pseudofs/pseudofs_vncache.c

Modified: head/sys/fs/pseudofs/pseudofs_vncache.c
==============================================================================
--- head/sys/fs/pseudofs/pseudofs_vncache.c	Sat Jun  6 00:38:15 2009	(r193555)
+++ head/sys/fs/pseudofs/pseudofs_vncache.c	Sat Jun  6 00:44:13 2009	(r193556)
@@ -270,13 +270,13 @@ pfs_vncache_free(struct vnode *vp)
  * The only way to improve this situation is to change the data structure
  * used to implement the cache.
  */
-void
-pfs_purge(struct pfs_node *pn)
+static void
+pfs_purge_locked(struct pfs_node *pn)
 {
 	struct pfs_vdata *pvd;
 	struct vnode *vnp;
 
-	mtx_lock(&pfs_vncache_mutex);
+	mtx_assert(&pfs_vncache_mutex, MA_OWNED);
 	pvd = pfs_vncache;
 	while (pvd != NULL) {
 		if (pvd->pvd_dead || (pn != NULL && pvd->pvd_pn == pn)) {
@@ -286,22 +286,26 @@ pfs_purge(struct pfs_node *pn)
 			VOP_LOCK(vnp, LK_EXCLUSIVE);
 			vgone(vnp);
 			VOP_UNLOCK(vnp, 0);
-			vdrop(vnp);
 			mtx_lock(&pfs_vncache_mutex);
+			vdrop(vnp);
 			pvd = pfs_vncache;
 		} else {
 			pvd = pvd->pvd_next;
 		}
 	}
+}
+
+void
+pfs_purge(struct pfs_node *pn)
+{
+
+	mtx_lock(&pfs_vncache_mutex);
+	pfs_purge_locked(pn);
 	mtx_unlock(&pfs_vncache_mutex);
 }
 
 /*
  * Free all vnodes associated with a defunct process
- *
- * XXXRW: It is unfortunate that pfs_exit() always acquires and releases two
- * mutexes (one of which is Giant) for every process exit, even if procfs
- * isn't mounted.
  */
 static void
 pfs_exit(void *arg, struct proc *p)
@@ -311,13 +315,11 @@ pfs_exit(void *arg, struct proc *p)
 
 	if (pfs_vncache == NULL)
 		return;
-	mtx_lock(&Giant);
 	mtx_lock(&pfs_vncache_mutex);
 	for (pvd = pfs_vncache, dead = 0; pvd != NULL; pvd = pvd->pvd_next)
 		if (pvd->pvd_pid == p->p_pid)
 			dead = pvd->pvd_dead = 1;
-	mtx_unlock(&pfs_vncache_mutex);
 	if (dead)
-		pfs_purge(NULL);
-	mtx_unlock(&Giant);
+		pfs_purge_locked(NULL);
+	mtx_unlock(&pfs_vncache_mutex);
 }