urcu-rbtree: Allow configuration of rcu_deref

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/urcu-rbtree.c b/urcu-rbtree.c
index da75e9ee2cfc3733f0d5400a567a843fbf4b6903..c73d1410f9d401f096a3e04482fb9a5985e82d95 100644 (file)
--- a/urcu-rbtree.c
+++ b/urcu-rbtree.c
@@ -161,6 +161,12 @@
 #define RBTREE_RCU_SUPPORT_TRANSPLANT
 #define RBTREE_RCU_SUPPORT
 
+#ifdef RBTREE_RCU_SUPPORT
+#define c_rcu_dereference(x)   rcu_dereference(x)
+#else
+#define c_rcu_dereference(x)   (x)
+#endif
+
 /*
  * Add internal mutex locking within the RBTree, for debugging. Enable this
  * define and add mutexes to RCU readers to debug races with with rotation or
@@ -241,7 +247,7 @@ static
 struct rcu_rbtree_node *get_parent_and_pos(struct rcu_rbtree_node *node,
                                unsigned int *pos)
 {
-       unsigned long parent_pos = rcu_dereference(node->parent);
+       unsigned long parent_pos = c_rcu_dereference(node->parent);
 
        *pos = (unsigned int) (parent_pos & 1UL);
        return (struct rcu_rbtree_node *) (parent_pos & ~1UL);
@@ -419,11 +425,11 @@ struct rcu_rbtree_node *rcu_rbtree_search(struct rcu_rbtree *rbtree,
        struct rcu_rbtree_node *xl;
 
        dbg_printf("searching point 0x%lx\n", (unsigned long) point);
-       x = rcu_dereference(x);
+       x = c_rcu_dereference(x);
 
        while (!rcu_rbtree_is_nil(rbtree, x)) {
                dbg_usleep(10);
-               xl = rcu_dereference(x->_left);
+               xl = c_rcu_dereference(x->_left);
                dbg_printf("search x %lx x_end %lx x_max_end %lx\n", (unsigned long) x->begin,
                                                (unsigned long) x->end, (unsigned long) x->max_end);
                dbg_printf("search xl %lx xl_end %lx xl_max_end %lx\n", (unsigned long) xl->begin,
@@ -438,7 +444,7 @@ struct rcu_rbtree_node *rcu_rbtree_search(struct rcu_rbtree *rbtree,
                        break;
                } else if (rbtree->comp(point, x->begin) > 0) {
                        dbg_printf("go right\n");
-                       x = rcu_dereference(x->_right);
+                       x = c_rcu_dereference(x->_right);
                } else {
                        dbg_printf("not found!\n");
                        x = make_nil(rbtree);
@@ -471,15 +477,15 @@ struct rcu_rbtree_node *rcu_rbtree_search_begin_key(struct rcu_rbtree *rbtree,
                                          struct rcu_rbtree_node *x,
                                          void *k)
 {
-       x = rcu_dereference(x);
+       x = c_rcu_dereference(x);
        int comp;
 
        while (!rcu_rbtree_is_nil(rbtree, x) && (comp = rbtree->comp(k, x->begin)) != 0) {
                dbg_usleep(10);
                if (comp < 0)
-                       x = rcu_dereference(x->_left);
+                       x = c_rcu_dereference(x->_left);
                else
-                       x = rcu_dereference(x->_right);
+                       x = c_rcu_dereference(x->_right);
        }
        return x;
 }
@@ -491,7 +497,7 @@ struct rcu_rbtree_node *rcu_rbtree_min_dup_decay(struct rcu_rbtree *rbtree,
 {
        struct rcu_rbtree_node *xl;
 
-       x = rcu_dereference(x);
+       x = c_rcu_dereference(x);
 
        if (rcu_rbtree_is_nil(rbtree, x)) {
                *zr = x;
@@ -499,7 +505,7 @@ struct rcu_rbtree_node *rcu_rbtree_min_dup_decay(struct rcu_rbtree *rbtree,
        } else
                *zr = x = dup_decay_node(rbtree, x);
 
-       while (!rcu_rbtree_is_nil(rbtree, xl = rcu_dereference(x->_left))) {
+       while (!rcu_rbtree_is_nil(rbtree, xl = c_rcu_dereference(x->_left))) {
                x = dup_decay_node(rbtree, xl);
                set_parent(x, get_decay(get_parent(x)), get_pos(x));
                get_parent(x)->_left = get_decay(get_parent(x)->_left);
@@ -513,7 +519,7 @@ struct rcu_rbtree_node *rcu_rbtree_min_update_decay(struct rcu_rbtree *rbtree,
 {
        struct rcu_rbtree_node *xl;
 
-       x = rcu_dereference(x);
+       x = c_rcu_dereference(x);
 
        if (rcu_rbtree_is_nil(rbtree, x))
                return x;
@@ -524,7 +530,7 @@ struct rcu_rbtree_node *rcu_rbtree_min_update_decay(struct rcu_rbtree *rbtree,
                           get_pos(x->_left));
        }
 
-       while (!rcu_rbtree_is_nil(rbtree, xl = rcu_dereference(x->_left))) {
+       while (!rcu_rbtree_is_nil(rbtree, xl = c_rcu_dereference(x->_left))) {
                x = xl;
                set_parent(x->_right, get_decay(get_parent(x->_right)),
                           get_pos(x->_right));
@@ -539,12 +545,12 @@ struct rcu_rbtree_node *rcu_rbtree_min(struct rcu_rbtree *rbtree,
 {
        struct rcu_rbtree_node *xl;
 
-       x = rcu_dereference(x);
+       x = c_rcu_dereference(x);
 
        if (rcu_rbtree_is_nil(rbtree, x))
                return x;
 
-       while (!rcu_rbtree_is_nil(rbtree, xl = rcu_dereference(x->_left)))
+       while (!rcu_rbtree_is_nil(rbtree, xl = c_rcu_dereference(x->_left)))
                x = xl;
        return x;
 }
@@ -554,12 +560,12 @@ struct rcu_rbtree_node *rcu_rbtree_max(struct rcu_rbtree *rbtree,
 {
        struct rcu_rbtree_node *xr;
 
-       x = rcu_dereference(x);
+       x = c_rcu_dereference(x);
 
        if (rcu_rbtree_is_nil(rbtree, x))
                return x;
 
-       while (!rcu_rbtree_is_nil(rbtree, xr = rcu_dereference(x->_right)))
+       while (!rcu_rbtree_is_nil(rbtree, xr = c_rcu_dereference(x->_right)))
                x = xr;
        return x;
 }
@@ -574,9 +580,9 @@ struct rcu_rbtree_node *rcu_rbtree_next(struct rcu_rbtree *rbtree,
        struct rcu_rbtree_node *xr, *y;
        unsigned int x_pos;
 
-       x = rcu_dereference(x);
+       x = c_rcu_dereference(x);
 
-       if (!rcu_rbtree_is_nil(rbtree, xr = rcu_dereference(x->_right)))
+       if (!rcu_rbtree_is_nil(rbtree, xr = c_rcu_dereference(x->_right)))
                return rcu_rbtree_min(rbtree, xr);
        y = get_parent_and_pos(x, &x_pos);
        while (!rcu_rbtree_is_nil(rbtree, y) && x_pos == IS_RIGHT) {
@@ -592,9 +598,9 @@ struct rcu_rbtree_node *rcu_rbtree_prev(struct rcu_rbtree *rbtree,
        struct rcu_rbtree_node *xl, *y;
        unsigned int x_pos;
 
-       x = rcu_dereference(x);
+       x = c_rcu_dereference(x);
 
-       if (!rcu_rbtree_is_nil(rbtree, xl = rcu_dereference(x->_left)))
+       if (!rcu_rbtree_is_nil(rbtree, xl = c_rcu_dereference(x->_left)))
                return rcu_rbtree_max(rbtree, xl);
        y = get_parent_and_pos(x, &x_pos);
        while (!rcu_rbtree_is_nil(rbtree, y) && x_pos == IS_LEFT) {