crush: fix tree node weight lookup

(cherry picked from commit f671d4cd9b36691ac4ef42cde44c1b7a84e13631)

Fix the node weight lookup for tree buckets by using a correct accessor.

Reflects ceph.git commit d287ade5bcbdca82a3aef145b92924cf1e856733.

Reviewed-by: Alex Elder <elder@inktank.com>
Signed-off-by: Sage Weil <sage@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/crush/crush.h b/include/linux/crush/crush.h
index 3f50369a50e8fa50860b713d6ef106f2416560fa..e7a8c9055cb21cb99c84d0fe155b1c0ee198b1d0 100644 (file)
--- a/include/linux/crush/crush.h
+++ b/include/linux/crush/crush.h
@@ -177,4 +177,9 @@ extern void crush_destroy_bucket_straw(struct crush_bucket_straw *b);
 extern void crush_destroy_bucket(struct crush_bucket *b);
 extern void crush_destroy(struct crush_map *map);
 
+static inline int crush_calc_tree_node(int i)
+{
+       return ((i+1) << 1)-1;
+}
+
 #endif

diff --git a/net/ceph/crush/crush.c b/net/ceph/crush/crush.c
index 8dd19a0deedc28e19c18ee3197111d56b4e5d69d..f23611d0cdee437e8ff42ae01d765b5a7167ae1b 100644 (file)
--- a/net/ceph/crush/crush.c
+++ b/net/ceph/crush/crush.c
@@ -37,9 +37,7 @@ int crush_get_bucket_item_weight(const struct crush_bucket *b, int p)
        case CRUSH_BUCKET_LIST:
                return ((struct crush_bucket_list *)b)->item_weights[p];
        case CRUSH_BUCKET_TREE:
-               if (p & 1)
-                       return ((struct crush_bucket_tree *)b)->node_weights[p];
-               return 0;
+               return ((struct crush_bucket_tree *)b)->node_weights[crush_calc_tree_node(p)];
        case CRUSH_BUCKET_STRAW:
                return ((struct crush_bucket_straw *)b)->item_weights[p];
        }