maple_tree: Optimize mas_node_walk() and standardize __mas_walk() a bit

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

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 39cf6bf18797081ce683fa261275abf26e13e1ac..6d2d71e05759a646f164459ab6b5911d2f2bcdb3 100644 (file)
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -2938,35 +2938,32 @@ static inline void mas_node_walk(struct ma_state *mas, enum maple_type type,
                unsigned long *range_min, unsigned long *range_max)
 {
        unsigned long *pivots = ma_pivots(mas_mn(mas), type);
-       unsigned long min, pivot = 0;
 
-       min = mas_safe_min(mas, pivots, mas->offset);
-       if (ma_is_dense(type)) {
-               // Linear node.
-               // What if mas->index != mas->last?
-               pivot = min = mas->index;
+       if (unlikely(ma_is_dense(type))) {
+               (*range_max) = (*range_min) = mas->index;
                mas->offset = mas->index = mas->min;
-               goto dense;
+               return;
        }
 
-       while (mas->offset < mt_slots[type]) {
-               pivot = _mas_safe_pivot(mas, pivots, mas->offset, type);
+       (*range_min) = mas_safe_min(mas, pivots, mas->offset);
+       if (unlikely(mas->offset == mt_pivots[type]))
+               goto max;
 
-               if (!pivot && mas->offset) {
-                       pivot = mas->max;
-                       break;
-               }
+       while (mas->offset < mt_pivots[type]) {
 
-               if (mas->index <= pivot)
-                       break;
+               (*range_max) = pivots[mas->offset];
+               if (!(*range_max) && mas->offset)
+                       goto max;
 
-               min = pivot + 1;
+               if (mas->index <= (*range_max))
+                       return;
+
+               (*range_min) = (*range_max) + 1;
                mas->offset++;
        }
 
-dense:
-       *range_min = min;
-       *range_max = pivot;
+max:
+       *range_max = mas->max;
 }
 
 /*
@@ -3067,18 +3064,16 @@ static inline bool __mas_walk(struct ma_state *mas, unsigned long *range_min,
 {
        struct maple_enode *next;
        enum maple_type type;
-       bool ret = false;
 
        while (true) {
-               mas->depth++;
                type = mte_node_type(mas->node);
+               mas->depth++;
 
                mas_node_walk(mas, type, range_min, range_max);
                if (ma_is_leaf(type)) // Leaf.
                        return true;
 
                next = mas_get_slot(mas, mas->offset);
-
                if (!next)
                        return false;
 
@@ -3088,7 +3083,7 @@ static inline bool __mas_walk(struct ma_state *mas, unsigned long *range_min,
                mas->node = next;
                mas->offset = 0;
        }
-       return ret;
+       return false;
 }
 
 /*