[SYSTEMTAP/PATCH v3 1/9] stp: rt: locking helper api

[Santosh Shukla <sshukla@mvista.com>]

Locking helper api used for replacing -rt and non-rt specific locks with common
helper lock starts with prefix stp_.  -rt version of locking api compatible to
kernel version 3.0 and greater. Older -rt version can be supported by adding
more kernel version checks, ifdefs in header file.. I haven't tested on
those(older) kernel version so not including code for now. Tested for
3.10.40-rt38 and 3.14.12-rt9.

Signed-off-by: Santosh Shukla <sshukla@mvista.com>
---
 runtime/stp_helper_lock.h | 67 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)
 create mode 100644 runtime/stp_helper_lock.h

diff --git a/runtime/stp_helper_lock.h b/runtime/stp_helper_lock.h
new file mode 100644
index 0000000..d1a69b4
--- /dev/null
+++ b/runtime/stp_helper_lock.h
@@ -0,0 +1,67 @@
+/* -*- linux-c -*- 
+ * Locking helper function api to support preempt-rt variant raw locks
+ * and keep legacy locking compatibility intact.
+ *
+ * Author: Santosh Shukla <sshukla@mvista.com>
+ *
+ * Copyright (C) 2014 Red Hat Inc.
+ * 
+ * This file is part of systemtap, and is free software.  You can
+ * redistribute it and/or modify it under the terms of the GNU General
+ * Public License (GPL); either version 2, or (at your option) any
+ * later version.
+ * */
+
+#ifndef _STP_HELPER_LOCK_H_
+#define _STP_HELPER_LOCK_H_
+
+#include <linux/spinlock.h>
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+
+#define STP_DEFINE_SPINLOCK(lock)	DEFINE_RAW_SPINLOCK(lock)
+
+static inline void stp_spin_lock(raw_spinlock_t *lock)		{ raw_spin_lock(lock); }
+static inline void stp_spin_unlock(raw_spinlock_t *lock)	{ raw_spin_unlock(lock); }
+
+#define stp_spin_lock_irqsave(lock, flags)		raw_spin_lock_irqsave(lock, flags)
+#define stp_spin_unlock_irqrestore(lock, flags)		raw_spin_unlock_irqrestore(lock, flags)
+
+
+#define STP_DEFINE_RWLOCK(lock)		DEFINE_RAW_SPINLOCK(lock)
+
+static inline void stp_read_lock(raw_spinlock_t *lock)		{ raw_spin_lock(lock); }
+static inline void stp_read_unlock(raw_spinlock_t *lock)	{ raw_spin_unlock(lock); }
+static inline void stp_write_lock(raw_spinlock_t *lock)		{ raw_spin_lock(lock); }
+static inline void stp_write_unlock(raw_spinlock_t *lock) 	{ raw_spin_unlock(lock); }
+
+#define stp_read_lock_irqsave(lock, flags)		raw_spin_lock_irqsave(lock, flags)
+#define stp_read_unlock_irqrestore(lock, flags)		raw_spin_unlock_irqrestore(lock, flags)
+#define stp_write_lock_irqsave(lock, flags)		raw_spin_lock_irqsave(lock, flags)
+#define stp_write_unlock_irqrestore(lock, flags) 	raw_spin_unlock_irqrestore(lock, flags)
+  
+#else
+#define STP_DEFINE_SPINLOCK(lock)	DEFINE_SPINLOCK(lock)
+
+static inline void stp_spin_lock(spinlock_t *lock)		{ spin_lock(lock); }
+static inline void stp_spin_unlock(spinlock_t *lock)		{ spin_unlock(lock); }
+
+#define stp_spin_lock_irqsave(lock, flags)		spin_lock_irqsave(lock, flags)
+#define stp_spin_unlock_irqrestore(lock, flags)		spin_unlock_irqrestore(lock, flags)
+
+#define STP_DEFINE_RWLOCK(lock)				DEFINE_RWLOCK(lock)
+
+static inline void stp_read_lock(rwlock_t *lock)	{ read_lock(lock); }
+static inline void stp_read_unlock(rwlock_t *lock)	{ read_unlock(lock); }
+static inline void stp_write_lock(rwlock_t *lock)	{ write_lock(lock); }
+static inline void stp_write_unlock(rwlock_t *lock)	{ write_unlock(lock); }
+
+#define stp_read_lock_irqsave(lock, flags)		read_lock_irqsave(lock, flags)
+#define stp_read_unlock_irqrestore(lock, flags)		read_unlock_irqrestore(lock, flags)
+#define stp_write_lock_irqsave(lock, flags)		write_lock_irqsave(lock, flags)
+#define stp_write_unlock_irqrestore(lock, flags) 	write_unlock_irqrestore(lock, flags)
+
+#endif
+
+#endif /* _STP_HELPER_LOCK_H_ */
+
-- 
1.8.3.1