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 fe2860c0244..5685a9a5dba 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;