maple_tree: Attempt to reduce split function size

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 3164b7f4bf5ebf130560b3a6e3fa2689d71286eb..2cf44fdb3c68dd2dd83087529fcfbbc528bbbe7c 100644 (file)
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -1915,7 +1915,7 @@ static inline void mab_set_b_end(struct maple_big_node *b_node,
 }
 
 /* Private
- * mas_combine_set_parent() - combine_separate helper function.  Sets the parent
+ * mas_set_split_parent() - combine_separate helper function.  Sets the parent
  * of @mas->node to either @left or @right, depending on @slot and @split
  *
  * @mas - the maple state with the node that needs a parent
@@ -1924,11 +1924,10 @@ static inline void mab_set_b_end(struct maple_big_node *b_node,
  * @slot - the slot the mas->node was placed
  * @split - the split location between @left and @right
  */
-static inline void mas_separate_set_parent(struct ma_state *mas,
-                                          struct maple_enode *left,
-                                          struct maple_enode *right,
-                                          unsigned char *slot,
-                                          unsigned char split)
+static inline void mas_set_split_parent(struct ma_state *mas,
+                                       struct maple_enode *left,
+                                       struct maple_enode *right,
+                                       unsigned char *slot, unsigned char split)
 {
        if (!mas->node)
                return;
@@ -1936,7 +1935,7 @@ static inline void mas_separate_set_parent(struct ma_state *mas,
        if ((*slot) <= split)
                mte_set_parent(mas->node, left, *slot);
        else
-               mte_set_parent(mas->node, right, (*slot) - split);
+               mte_set_parent(mas->node, right, (*slot) - split - 1);
 
        (*slot)++;
 }
@@ -1986,7 +1985,7 @@ static inline int mas_combine_separate(struct ma_state *mas,
                struct maple_subtree_state *mast, unsigned char count)
 {
        unsigned char split, r_end, mid_split;
-       unsigned char slot = 0, l_slot = 0, r_slot = 0;
+       unsigned char slot = 0, l_slot = 0;
        struct maple_enode *left = NULL, *middle = NULL, *right = NULL;
        unsigned long range_min, range_max;
 
@@ -2014,9 +2013,9 @@ static inline int mas_combine_separate(struct ma_state *mas,
 
                /* Set parents from previous run */
                slot = mas_get_slot(&l_mas);
-               mas_separate_set_parent(&l_mas, left, right, &slot, split);
-               mas_separate_set_parent(&m_mas, left, right, &slot, split);
-               mas_separate_set_parent(&r_mas, left, right, &slot, split);
+               mas_set_split_parent(&l_mas, left, right, &slot, split);
+               mas_set_split_parent(&m_mas, left, right, &slot, split);
+               mas_set_split_parent(&r_mas, left, right, &slot, split);
 
                /* Copy data from mast->bn to new nodes */
                l_mas.node = left;
@@ -2090,7 +2089,6 @@ static inline int mas_combine_separate(struct ma_state *mas,
                                   &range_min, &range_max)) {
                        mas_set_slot(mast->orig_r, r_end + 1);
                }
-               r_slot = mas_get_slot(mast->orig_r);
                /* Set up the left side of things */
                mas_set_slot(mast->orig_l, 0);
                mast->orig_l->index = l_mas.min;
@@ -2287,11 +2285,7 @@ static inline int mas_split(struct ma_state *mas,
                        mas_set_slot(&r_mas, mas_get_slot(&l_mas) + 1);
                } else {
                        unsigned char p_slot;
-                       /* TODO: Check rebalancing to avoid continuing walking
-                        * up if there is space in a neighbour.
-                        * TODO: Use the same splitting as leaves, using height
-                        * to figure if there is enough room below.
-                        */
+                       /* Note, look into shifting data left or right */
                        /* internal node split - cut in half for now. */
                        split = slot_cnt / 2;
                        j = mab_mas_cp(b_node, 0, split, &l_mas, 0);
@@ -2299,23 +2293,10 @@ static inline int mas_split(struct ma_state *mas,
                        r_mas.min = l_mas.max + 1;
                        mab_mas_cp(b_node, j, slot_cnt, &r_mas, 0);
                        p_slot = mas_get_slot(&orig_l_mas);
-                       if (p_slot <= split) { // prev left side is on left.
-                               mte_set_parent(orig_l_mas.node, l_mas.node,
-                                              p_slot);
-                       }
-                       else {
-                               mte_set_parent(orig_l_mas.node, r_mas.node,
-                                              p_slot - split - 1);
-                       }
-
-                       p_slot = mas_get_slot(&orig_r_mas);
-                       if (p_slot <= split) {// prev right side is on left.
-                               mte_set_parent(orig_r_mas.node, l_mas.node,
-                                              p_slot);
-                       } else {
-                               mte_set_parent(orig_r_mas.node, r_mas.node,
-                                              p_slot - split - 1);
-                       }
+                       mas_set_split_parent(&orig_l_mas, l_mas.node,
+                                               r_mas.node, &p_slot, split);
+                       mas_set_split_parent(&orig_r_mas, l_mas.node,
+                                               r_mas.node, &p_slot, split);
                }
 
                b_node->b_end = 0;