api: spinlock_recursive: added recursive spinlock

Applications can use recursive spinlocks to avoid deadlock from
single thread acquiring the same lock multiple times. Recursive
locks are used in legacy applications. ODP version of recursive
spinlock enable porting of those applications.

Signed-off-by: Petri Savolainen <petri.savolainen@nokia.com>
Reviewed-by: Bill Fischofer <bill.fischofer@linaro.org>
Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>

Conflicts:
	platform/linux-generic/Makefile.am

1 files changed, 82 insertions, 0 deletions

diff --git a/include/odp/api/spinlock_recursive.h b/include/odp/api/spinlock_recursive.h
new file mode 100644
index 000000000..46b6be762
--- /dev/null
+++ b/include/odp/api/spinlock_recursive.h
@@ -0,0 +1,82 @@
+/* Copyright (c) 2015, Linaro Limited
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier:     BSD-3-Clause
+ */
+
+/**
+ * @file
+ *
+ * ODP recursive spinlock
+ */
+
+#ifndef ODP_API_SPINLOCK_RECURSIVE_H_
+#define ODP_API_SPINLOCK_RECURSIVE_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** @addtogroup odp_synchronizers
+ *  Operations on recursive spinlocks.
+ *  @{
+ */
+
+/**
+ * @typedef odp_spinlock_recursive_t
+ * Recursive spinlock
+ *
+ * A thread can acquire the lock multiple times without a deadlock. To release
+ * the lock, the thread must unlock it the same number of times.
+ */
+
+/**
+ * Initialize recursive spinlock.
+ *
+ * @param lock    Pointer to a lock
+ */
+void odp_spinlock_recursive_init(odp_spinlock_recursive_t *lock);
+
+/**
+ * Acquire recursive spinlock.
+ *
+ * @param lock    Pointer to a lock
+ */
+void odp_spinlock_recursive_lock(odp_spinlock_recursive_t *lock);
+
+/**
+ * Try to acquire recursive spinlock.
+ *
+ * @param lock    Pointer to a lock
+ *
+ * @retval 1 lock acquired
+ * @retval 0 lock not acquired
+ */
+int odp_spinlock_recursive_trylock(odp_spinlock_recursive_t *lock);
+
+/**
+ * Release recursive spinlock.
+ *
+ * @param lock    Pointer to a lock
+ */
+void odp_spinlock_recursive_unlock(odp_spinlock_recursive_t *lock);
+
+/**
+ * Check if recursive spinlock is locked.
+ *
+ * @param lock    Pointer to a lock
+ *
+ * @retval 1 lock is locked
+ * @retval 0 lock is not locked
+ */
+int odp_spinlock_recursive_is_locked(odp_spinlock_recursive_t *lock);
+
+/**
+ * @}
+ */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif