waitqueue: add in_waitqueue field

[userspace-rcu.git] / urcu / waitqueue-lifo.h

diff --git a/urcu/waitqueue-lifo.h b/urcu/waitqueue-lifo.h
index fccba17844001cdd6f678ff9ad7bfb406b72465c..96b211c68355bbd9611c4895ebaab5a295e961fb 100644 (file)
--- a/urcu/waitqueue-lifo.h
+++ b/urcu/waitqueue-lifo.h
@@ -45,6 +45,7 @@ enum urcu_wait_state {
 struct urcu_wait_node {
        struct cds_lfs_node node;
        int32_t state;  /* enum urcu_wait_state */
+       int in_waitqueue;
 };
 
 #define URCU_WAIT_NODE_INIT(name, _state)              \
@@ -88,6 +89,8 @@ static inline
 bool urcu_wait_add(struct urcu_wait_queue *queue,
                struct urcu_wait_node *node)
 {
+       cds_lfs_node_init(&node->node);
+       CMM_STORE_SHARED(node->in_waitqueue, true);
        return cds_lfs_push(&queue->stack, &node->node);
 }
 
@@ -122,6 +125,13 @@ void urcu_wait_node_init(struct urcu_wait_node *node,
 {
        urcu_wait_set_state(node, state);
        cds_lfs_node_init(&node->node);
+       node->in_waitqueue = false;
+}
+
+static inline
+bool urcu_in_waitqueue(struct urcu_wait_node *node)
+{
+       return CMM_LOAD_SHARED(node->in_waitqueue);
 }
 
 /*
@@ -206,7 +216,7 @@ int urcu_dequeue_wake_single(struct urcu_wait_queue *queue)
        if (!node)
                return -ENOENT;
        wait_node = caa_container_of(node, struct urcu_wait_node, node);
-       CMM_STORE_SHARED(wait_node->node.next, NULL);
+       CMM_STORE_SHARED(wait_node->in_waitqueue, false);
        /* Don't wake already running threads */
        if (!(wait_node->state & URCU_WAIT_RUNNING))
                ret = urcu_adaptative_wake_up(wait_node);
@@ -247,7 +257,7 @@ int urcu_wake_all_waiters(struct urcu_waiters *waiters)
                struct urcu_wait_node *wait_node =
                        caa_container_of(iter, struct urcu_wait_node, node);
 
-               CMM_STORE_SHARED(wait_node->node.next, NULL);
+               CMM_STORE_SHARED(wait_node->in_waitqueue, false);
                /* Don't wake already running threads */
                if (wait_node->state & URCU_WAIT_RUNNING)
                        continue;