Add a helper to do what is needed when the maple copy node contains a new root node. This is useful for future commits and is self-documenting code. Signed-off-by: Liam R. Howlett --- lib/maple_tree.c | 71 ++++++++++++++++++++++++++---------------------- 1 file changed, 38 insertions(+), 33 deletions(-) diff --git a/lib/maple_tree.c b/lib/maple_tree.c index 005cf46aadc10..326d6026afee3 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -3330,6 +3330,43 @@ static void mas_spanning_rebalance(struct ma_state *mas, mas_spanning_rebalance_loop(mas, mast, count); } +static inline bool cp_is_new_root(struct maple_copy *cp, struct ma_state *mas) +{ + if (cp->min || cp->max != ULONG_MAX) + return false; + + if (cp->d_count != 1) { + enum maple_type mt = maple_arange_64; + + if (!mt_is_alloc(mas->tree)) + mt = maple_range_64; + + cp->data = cp->d_count; + cp->s_count = 0; + dst_setup(cp, mas, mt); + init_cp_src(cp); + node_copy(mas, cp->src[0].node, 0, cp->data, cp->max, maple_copy, + cp->dst[0].node, 0, mt); + node_finalise(cp->dst[0].node, mt, cp->end + 1); + /* + * Warning, see cp_leaf_init() comment and rcu_assign_pointer() + * documentation. Since this is a new root, there are no + * read-side operations that can view it until it is insert into + * the tree after an rcu_assign_pointer() call. + */ + RCU_INIT_POINTER(cp->slot[0], mt_mk_node(cp->dst[0].node, mt)); + cp->height++; + } + WARN_ON_ONCE(cp->dst[0].node != mte_to_node( + mt_slot_locked(mas->tree, cp->slot, 0))); + cp->dst[0].node->parent = ma_parent_ptr(mas_tree_parent(mas)); + mas->min = 0; + mas->max = ULONG_MAX; + mas->depth = 0; + mas->node = mas_root_locked(mas); + return true; +} + /* * spanning_ascend() - See if a spanning store operation has to keep walking up * the tree @@ -3352,40 +3389,8 @@ static bool spanning_ascend(struct maple_copy *cp, struct ma_state *mas, } cp_dst_to_slots(cp, l_wr_mas->mas->min, r_wr_mas->mas->max, mas); - if (!cp->min && cp->max == ULONG_MAX) { - /* New root */ - if (cp->d_count != 1) { - enum maple_type mt = maple_arange_64; - - if (!mt_is_alloc(mas->tree)) - mt = maple_range_64; - - cp->data = cp->d_count; - cp->s_count = 0; - dst_setup(cp, mas, mt); - init_cp_src(cp); - node_copy(mas, cp->src[0].node, 0, cp->data, cp->max, maple_copy, - cp->dst[0].node, 0, mt); - node_finalise(cp->dst[0].node, mt, cp->end + 1); - /* - * Warning, see cp_leaf_init() comment and rcu_assign_pointer() - * documentation. Since this is a new root, there are no - * read-side operations that can view it until it is insert into - * the tree after an rcu_assign_pointer() call. - */ - RCU_INIT_POINTER(cp->slot[0], - mt_mk_node(cp->dst[0].node, mt)); - cp->height++; - } - WARN_ON_ONCE(cp->dst[0].node != mte_to_node( - mt_slot_locked(mas->tree, cp->slot, 0))); - cp->dst[0].node->parent = ma_parent_ptr(mas_tree_parent(mas)); - mas->min = 0; - mas->max = ULONG_MAX; - mas->depth = 0; - mas->node = mas_root_locked(mas); + if (cp_is_new_root(cp, mas)) return false; - } /* Converged and has a single destination */ if ((cp->d_count == 1) && -- 2.47.3