1 files changed, 60 insertions, 0 deletions
diff --git a/include/linux/timerqueue.h b/include/linux/timerqueue.h
new file mode 100644
index 000000000..adc80e291
--- /dev/null
+++ b/include/linux/timerqueue.h
@@ -0,0 +1,60 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_TIMERQUEUE_H
+#define _LINUX_TIMERQUEUE_H
+
+#include <linux/rbtree.h>
+#include <linux/ktime.h>
+
+
+struct timerqueue_node {
+	struct rb_node node;
+	ktime_t expires;
+};
+
+struct timerqueue_head {
+	struct rb_root_cached rb_root;
+};
+
+
+extern bool timerqueue_add(struct timerqueue_head *head,
+			   struct timerqueue_node *node);
+extern bool timerqueue_del(struct timerqueue_head *head,
+			   struct timerqueue_node *node);
+extern struct timerqueue_node *timerqueue_iterate_next(
+						struct timerqueue_node *node);
+
+/**
+ * timerqueue_getnext - Returns the timer with the earliest expiration time
+ *
+ * @head: head of timerqueue
+ *
+ * Returns a pointer to the timer node that has the earliest expiration time.
+ */
+static inline
+struct timerqueue_node *timerqueue_getnext(struct timerqueue_head *head)
+{
+	struct rb_node *leftmost = rb_first_cached(&head->rb_root);
+
+	return rb_entry_safe(leftmost, struct timerqueue_node, node);
+}
+
+static inline void timerqueue_init(struct timerqueue_node *node)
+{
+	RB_CLEAR_NODE(&node->node);
+}
+
+static inline bool timerqueue_node_queued(struct timerqueue_node *node)
+{
+	return !RB_EMPTY_NODE(&node->node);
+}
+
+static inline bool timerqueue_node_expires(struct timerqueue_node *node)
+{
+	return node->expires;
+}
+
+static inline void timerqueue_init_head(struct timerqueue_head *head)
+{
+	head->rb_root = RB_ROOT_CACHED;
+}
+#endif /* _LINUX_TIMERQUEUE_H */