use atomic loads in critnib find_pre/succ

Author: bratpiorka

src/critnib/critnib.c

@@ -537,7 +537,6 @@ find_predecessor(struct critnib_node *__restrict n) {
         }
 
         utils_atomic_load_acquire_ptr((void **)&n->child[nib], (void **)&n);
-
         if (!n) {
             return NULL;
         }
@@ -644,7 +643,9 @@ void *critnib_find_le(struct critnib *c, word key) {
 static struct critnib_leaf *find_successor(struct critnib_node *__restrict n) {
     while (1) {
         unsigned nib;
+        struct critnib_node *m = NULL;
         for (nib = 0; nib <= NIB; nib++) {
+            utils_atomic_load_acquire_ptr((void **)&n->child[nib], (void **)&m);
             if (n->child[nib]) {
                 break;
             }
@@ -654,8 +655,7 @@ static struct critnib_leaf *find_successor(struct critnib_node *__restrict n) {
             return NULL;
         }
 
-        n = n->child[nib];
-
+        utils_atomic_load_acquire_ptr((void **)&n->child[nib], (void **)&n);
         if (!n) {
             return NULL;
         }