ceph: use rbtree for snap_realms

Switch from radix tree to rbtree for snap realms.  This is much more
appropriate given that realm keys are few and far between.

Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 5 insertions, 11 deletions

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 81840d6b68a4..02834cecc3a0 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2097,9 +2097,8 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
 {
         struct ceph_mds_session *session = NULL;
         struct ceph_msg *reply;
+        struct rb_node *p;
         int err;
-        int got;
-        u64 next_snap_ino = 0;
         struct ceph_pagelist *pagelist;
 
         pr_info("reconnect to recovering mds%d\n", mds);
@@ -2155,14 +2154,10 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
          * parent for all of our realms.  If the mds has any newer info,
          * it will tell us.
          */
-        next_snap_ino = 0;
-        while (1) {
-                struct ceph_snap_realm *realm;
+        for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
+                struct ceph_snap_realm *realm =
+                        rb_entry(p, struct ceph_snap_realm, node);
                 struct ceph_mds_snaprealm_reconnect sr_rec;
-                got = radix_tree_gang_lookup(&mdsc->snap_realms,
-                                             (void **)&realm, next_snap_ino, 1);
-                if (!got)
-                        break;
 
                 dout(" adding snap realm %llx seq %lld parent %llx\n",
                      realm->ino, realm->seq, realm->parent_ino);
@@ -2172,7 +2167,6 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
                 err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
                 if (err)
                         goto fail;
-                next_snap_ino = realm->ino + 1;
         }
 
 send:
@@ -2603,7 +2597,7 @@ int ceph_mdsc_init(struct ceph_mds_client *mdsc, struct ceph_client *client)
         mdsc->max_sessions = 0;
         mdsc->stopping = 0;
         init_rwsem(&mdsc->snap_rwsem);
-        INIT_RADIX_TREE(&mdsc->snap_realms, GFP_NOFS);
+        mdsc->snap_realms = RB_ROOT;
         INIT_LIST_HEAD(&mdsc->snap_empty);
         spin_lock_init(&mdsc->snap_empty_lock);
         mdsc->last_tid = 0;