locking: Separate rwlock api from spinlock api

Move the rwlock smp api defines and functions into a separate header
file. Makes the -rt selection simpler and less intrusive.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 277 insertions, 0 deletions

diff --git a/include/linux/rwlock_api_smp.h b/include/linux/rwlock_api_smp.h
new file mode 100644
index 000000000000..090f876f828d
--- /dev/null
+++ b/include/linux/rwlock_api_smp.h
@@ -0,0 +1,277 @@
+#ifndef __LINUX_RWLOCK_API_SMP_H
+#define __LINUX_RWLOCK_API_SMP_H
+
+#ifndef __LINUX_SPINLOCK_API_SMP_H
+# error "please don't include this file directly"
+#endif
+
+/*
+ * include/linux/rwlock_api_smp.h
+ *
+ * spinlock API declarations on SMP (and debug)
+ * (implemented in kernel/spinlock.c)
+ *
+ * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ */
+
+void __lockfunc _read_lock(rwlock_t *lock)              __acquires(lock);
+void __lockfunc _write_lock(rwlock_t *lock)             __acquires(lock);
+void __lockfunc _read_lock_bh(rwlock_t *lock)           __acquires(lock);
+void __lockfunc _write_lock_bh(rwlock_t *lock)          __acquires(lock);
+void __lockfunc _read_lock_irq(rwlock_t *lock)          __acquires(lock);
+void __lockfunc _write_lock_irq(rwlock_t *lock)         __acquires(lock);
+unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock)
+                                                        __acquires(lock);
+unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock)
+                                                        __acquires(lock);
+int __lockfunc _read_trylock(rwlock_t *lock);
+int __lockfunc _write_trylock(rwlock_t *lock);
+void __lockfunc _read_unlock(rwlock_t *lock)            __releases(lock);
+void __lockfunc _write_unlock(rwlock_t *lock)           __releases(lock);
+void __lockfunc _read_unlock_bh(rwlock_t *lock)         __releases(lock);
+void __lockfunc _write_unlock_bh(rwlock_t *lock)        __releases(lock);
+void __lockfunc _read_unlock_irq(rwlock_t *lock)        __releases(lock);
+void __lockfunc _write_unlock_irq(rwlock_t *lock)       __releases(lock);
+void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+                                                        __releases(lock);
+void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+                                                        __releases(lock);
+
+#ifdef CONFIG_INLINE_READ_LOCK
+#define _read_lock(lock) __read_lock(lock)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_LOCK
+#define _write_lock(lock) __write_lock(lock)
+#endif
+
+#ifdef CONFIG_INLINE_READ_LOCK_BH
+#define _read_lock_bh(lock) __read_lock_bh(lock)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_LOCK_BH
+#define _write_lock_bh(lock) __write_lock_bh(lock)
+#endif
+
+#ifdef CONFIG_INLINE_READ_LOCK_IRQ
+#define _read_lock_irq(lock) __read_lock_irq(lock)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_LOCK_IRQ
+#define _write_lock_irq(lock) __write_lock_irq(lock)
+#endif
+
+#ifdef CONFIG_INLINE_READ_LOCK_IRQSAVE
+#define _read_lock_irqsave(lock) __read_lock_irqsave(lock)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_LOCK_IRQSAVE
+#define _write_lock_irqsave(lock) __write_lock_irqsave(lock)
+#endif
+
+#ifdef CONFIG_INLINE_READ_TRYLOCK
+#define _read_trylock(lock) __read_trylock(lock)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_TRYLOCK
+#define _write_trylock(lock) __write_trylock(lock)
+#endif
+
+#ifdef CONFIG_INLINE_READ_UNLOCK
+#define _read_unlock(lock) __read_unlock(lock)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_UNLOCK
+#define _write_unlock(lock) __write_unlock(lock)
+#endif
+
+#ifdef CONFIG_INLINE_READ_UNLOCK_BH
+#define _read_unlock_bh(lock) __read_unlock_bh(lock)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_UNLOCK_BH
+#define _write_unlock_bh(lock) __write_unlock_bh(lock)
+#endif
+
+#ifdef CONFIG_INLINE_READ_UNLOCK_IRQ
+#define _read_unlock_irq(lock) __read_unlock_irq(lock)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_UNLOCK_IRQ
+#define _write_unlock_irq(lock) __write_unlock_irq(lock)
+#endif
+
+#ifdef CONFIG_INLINE_READ_UNLOCK_IRQRESTORE
+#define _read_unlock_irqrestore(lock, flags) __read_unlock_irqrestore(lock, flags)
+#endif
+
+#ifdef CONFIG_INLINE_WRITE_UNLOCK_IRQRESTORE
+#define _write_unlock_irqrestore(lock, flags) __write_unlock_irqrestore(lock, flags)
+#endif
+
+static inline int __read_trylock(rwlock_t *lock)
+{
+        preempt_disable();
+        if (_raw_read_trylock(lock)) {
+                rwlock_acquire_read(&lock->dep_map, 0, 1, _RET_IP_);
+                return 1;
+        }
+        preempt_enable();
+        return 0;
+}
+
+static inline int __write_trylock(rwlock_t *lock)
+{
+        preempt_disable();
+        if (_raw_write_trylock(lock)) {
+                rwlock_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+                return 1;
+        }
+        preempt_enable();
+        return 0;
+}
+
+/*
+ * If lockdep is enabled then we use the non-preemption spin-ops
+ * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are
+ * not re-enabled during lock-acquire (which the preempt-spin-ops do):
+ */
+#if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC)
+
+static inline void __read_lock(rwlock_t *lock)
+{
+        preempt_disable();
+        rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
+        LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
+}
+
+static inline unsigned long __read_lock_irqsave(rwlock_t *lock)
+{
+        unsigned long flags;
+
+        local_irq_save(flags);
+        preempt_disable();
+        rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
+        LOCK_CONTENDED_FLAGS(lock, _raw_read_trylock, _raw_read_lock,
+                             _raw_read_lock_flags, &flags);
+        return flags;
+}
+
+static inline void __read_lock_irq(rwlock_t *lock)
+{
+        local_irq_disable();
+        preempt_disable();
+        rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
+        LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
+}
+
+static inline void __read_lock_bh(rwlock_t *lock)
+{
+        local_bh_disable();
+        preempt_disable();
+        rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
+        LOCK_CONTENDED(lock, _raw_read_trylock, _raw_read_lock);
+}
+
+static inline unsigned long __write_lock_irqsave(rwlock_t *lock)
+{
+        unsigned long flags;
+
+        local_irq_save(flags);
+        preempt_disable();
+        rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+        LOCK_CONTENDED_FLAGS(lock, _raw_write_trylock, _raw_write_lock,
+                             _raw_write_lock_flags, &flags);
+        return flags;
+}
+
+static inline void __write_lock_irq(rwlock_t *lock)
+{
+        local_irq_disable();
+        preempt_disable();
+        rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+        LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
+}
+
+static inline void __write_lock_bh(rwlock_t *lock)
+{
+        local_bh_disable();
+        preempt_disable();
+        rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+        LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
+}
+
+static inline void __write_lock(rwlock_t *lock)
+{
+        preempt_disable();
+        rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+        LOCK_CONTENDED(lock, _raw_write_trylock, _raw_write_lock);
+}
+
+#endif /* CONFIG_PREEMPT */
+
+static inline void __write_unlock(rwlock_t *lock)
+{
+        rwlock_release(&lock->dep_map, 1, _RET_IP_);
+        _raw_write_unlock(lock);
+        preempt_enable();
+}
+
+static inline void __read_unlock(rwlock_t *lock)
+{
+        rwlock_release(&lock->dep_map, 1, _RET_IP_);
+        _raw_read_unlock(lock);
+        preempt_enable();
+}
+
+static inline void __read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+{
+        rwlock_release(&lock->dep_map, 1, _RET_IP_);
+        _raw_read_unlock(lock);
+        local_irq_restore(flags);
+        preempt_enable();
+}
+
+static inline void __read_unlock_irq(rwlock_t *lock)
+{
+        rwlock_release(&lock->dep_map, 1, _RET_IP_);
+        _raw_read_unlock(lock);
+        local_irq_enable();
+        preempt_enable();
+}
+
+static inline void __read_unlock_bh(rwlock_t *lock)
+{
+        rwlock_release(&lock->dep_map, 1, _RET_IP_);
+        _raw_read_unlock(lock);
+        preempt_enable_no_resched();
+        local_bh_enable_ip((unsigned long)__builtin_return_address(0));
+}
+
+static inline void __write_unlock_irqrestore(rwlock_t *lock,
+                                             unsigned long flags)
+{
+        rwlock_release(&lock->dep_map, 1, _RET_IP_);
+        _raw_write_unlock(lock);
+        local_irq_restore(flags);
+        preempt_enable();
+}
+
+static inline void __write_unlock_irq(rwlock_t *lock)
+{
+        rwlock_release(&lock->dep_map, 1, _RET_IP_);
+        _raw_write_unlock(lock);
+        local_irq_enable();
+        preempt_enable();
+}
+
+static inline void __write_unlock_bh(rwlock_t *lock)
+{
+        rwlock_release(&lock->dep_map, 1, _RET_IP_);
+        _raw_write_unlock(lock);
+        preempt_enable_no_resched();
+        local_bh_enable_ip((unsigned long)__builtin_return_address(0));
+}
+
+#endif /* __LINUX_RWLOCK_API_SMP_H */