svn commit: r332879 - head/sys/kern

[Mateusz Guzik]

Author: mjg
Date: Mon Apr 23 07:52:10 2018
New Revision: 332879
URL: https://svnweb.freebsd.org/changeset/base/332879

Log:
  lockf: skip the hard work in lf_purgelocks if possible
  
  Tested by:      pho

Modified:
  head/sys/kern/kern_lockf.c

Modified: head/sys/kern/kern_lockf.c
==============================================================================
--- head/sys/kern/kern_lockf.c	Mon Apr 23 07:51:19 2018	(r332878)
+++ head/sys/kern/kern_lockf.c	Mon Apr 23 07:52:10 2018	(r332879)
@@ -777,6 +777,12 @@ lf_purgelocks(struct vnode *vp, struct lockf **statep)
 		return;
 	}
 	*statep = NULL;
+	if (LIST_EMPTY(&state->ls_active) && state->ls_threads == 0) {
+		KASSERT(LIST_EMPTY(&state->ls_pending),
+		    ("freeing state with pending locks"));
+		VI_UNLOCK(vp);
+		goto out_free;
+	}
 	state->ls_threads++;
 	VI_UNLOCK(vp);
 
@@ -823,6 +829,7 @@ lf_purgelocks(struct vnode *vp, struct lockf **statep)
 		LIST_REMOVE(lock, lf_link);
 		lf_free_lock(lock);
 	}
+out_free:
 	sx_xlock(&lf_lock_states_lock);
 	LIST_REMOVE(state, ls_link);
 	sx_xunlock(&lf_lock_states_lock);