dlm: convert rsb list to rb_tree

Change the linked lists to rb_tree's in the rsb
hash table to speed up searches.  Slow rsb searches
were having a large impact on gfs2 performance due
to the large number of dlm locks gfs2 uses.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index fe2860c02449..5685a9a5dba2 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -103,8 +103,8 @@ struct dlm_dirtable {
 };
 
 struct dlm_rsbtable {
-	struct list_head	list;
-	struct list_head	toss;
+	struct rb_root		keep;
+	struct rb_root		toss;
 	spinlock_t		lock;
 };
 
@@ -285,7 +285,10 @@ struct dlm_rsb {
 	unsigned long		res_toss_time;
 	uint32_t		res_first_lkid;
 	struct list_head	res_lookup;	/* lkbs waiting on first */
-	struct list_head	res_hashchain;	/* rsbtbl */
+	union {
+		struct list_head	res_hashchain;
+		struct rb_node		res_hashnode;	/* rsbtbl */
+	};
 	struct list_head	res_grantqueue;
 	struct list_head	res_convertqueue;
 	struct list_head	res_waitqueue;