1 files changed, 61 insertions, 0 deletions

diff --git a/include/litmus/prioq_lock.h b/include/litmus/prioq_lock.h
new file mode 100644
index 000000000000..f3c11d241991
--- /dev/null
+++ b/include/litmus/prioq_lock.h
@@ -0,0 +1,61 @@
+#ifndef LITMUS_PRIOQ_H
+#define LITMUS_PRIOQ_H
+
+#include <litmus/litmus.h>
+#include <litmus/binheap.h>
+#include <litmus/locking.h>
+
+/* struct for semaphore with priority inheritance */
+struct prioq_mutex {
+        struct litmus_lock litmus_lock;
+
+        /* current resource holder */
+        struct task_struct *owner;
+
+        /* highest-priority waiter */
+        struct task_struct *hp_waiter;
+
+        /* priority-ordered queue of waiting tasks.
+         * Ironically, we don't use a binheap because that would make DGL
+         * implementation a LOT harder. */
+        wait_queue_head_t       wait;
+
+        /* we do some nesting within spinlocks, so we can't use the normal
+         sleeplocks found in wait_queue_head_t. */
+        raw_spinlock_t          lock;
+};
+
+static inline struct prioq_mutex* prioq_mutex_from_lock(struct litmus_lock* lock)
+{
+        return container_of(lock, struct prioq_mutex, litmus_lock);
+}
+
+#ifdef CONFIG_LITMUS_DGL_SUPPORT
+int prioq_mutex_is_owner(struct litmus_lock *l, struct task_struct *t);
+int prioq_mutex_dgl_lock(struct litmus_lock *l, dgl_wait_state_t* dgl_wait, wait_queue_t* wq_node);
+void prioq_mutex_enable_priority(struct litmus_lock *l, dgl_wait_state_t* dgl_wait);
+void prioq_mutex_dgl_quick_lock(struct litmus_lock *l, struct litmus_lock *cur_lock,
+                                                                struct task_struct* t, wait_queue_t *q);
+int prioq_mutex_dgl_can_quick_lock(struct litmus_lock *l, struct task_struct *t);
+#endif
+
+void prioq_mutex_propagate_increase_inheritance(struct litmus_lock* l,
+                                                                                          struct task_struct* t,
+                                                                                          raw_spinlock_t* to_unlock,
+                                                                                          unsigned long irqflags);
+
+void prioq_mutex_propagate_decrease_inheritance(struct litmus_lock* l,
+                                                                                          struct task_struct* t,
+                                                                                          raw_spinlock_t* to_unlock,
+                                                                                          unsigned long irqflags);
+
+
+int prioq_mutex_lock(struct litmus_lock* l);
+int prioq_mutex_unlock(struct litmus_lock* l);
+int prioq_mutex_close(struct litmus_lock* l);
+void prioq_mutex_free(struct litmus_lock* l);
+struct litmus_lock* prioq_mutex_new(struct litmus_lock_ops*);
+
+
+#endif
+