[patch 02/23] locking: Split rwlock from spinlock headers

From: Thomas Gleixner
Date: Sun Dec 06 2009 - 13:02:41 EST


Move the rwlock defines and inlines into separate header files. This
makes the selection for -rt easier.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
include/linux/rwlock.h | 127 +++++++++++++++++++++++++++++++++++++++++
include/linux/rwlock_types.h | 56 ++++++++++++++++++
include/linux/spinlock.h | 100 ++------------------------------
include/linux/spinlock_types.h | 43 +------------
4 files changed, 197 insertions(+), 129 deletions(-)

Index: linux-2.6-tip/include/linux/rwlock.h
===================================================================
--- /dev/null
+++ linux-2.6-tip/include/linux/rwlock.h
@@ -0,0 +1,127 @@
+#ifndef __LINUX_RWLOCK_H
+#define __LINUX_RWLOCK_H
+
+#ifndef __LINUX_SPINLOCK_H
+# error "please don't include this file directly"
+#endif
+
+/*
+ * rwlock related methods
+ *
+ * split out from spinlock.h
+ *
+ * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ */
+
+extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+ extern void __rwlock_init(rwlock_t *lock, const char *name,
+ struct lock_class_key *key);
+# define rwlock_init(lock) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ __rwlock_init((lock), #lock, &__key); \
+} while (0)
+#else
+# define rwlock_init(lock) \
+ do { *(lock) = __RW_LOCK_UNLOCKED(lock); } while (0)
+#endif
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+ extern void _raw_read_lock(rwlock_t *lock);
+#define _raw_read_lock_flags(lock, flags) _raw_read_lock(lock)
+ extern int _raw_read_trylock(rwlock_t *lock);
+ extern void _raw_read_unlock(rwlock_t *lock);
+ extern void _raw_write_lock(rwlock_t *lock);
+#define _raw_write_lock_flags(lock, flags) _raw_write_lock(lock)
+ extern int _raw_write_trylock(rwlock_t *lock);
+ extern void _raw_write_unlock(rwlock_t *lock);
+#else
+# define _raw_read_lock(rwlock) __raw_read_lock(&(rwlock)->raw_lock)
+# define _raw_read_lock_flags(lock, flags) \
+ __raw_read_lock_flags(&(lock)->raw_lock, *(flags))
+# define _raw_read_trylock(rwlock) __raw_read_trylock(&(rwlock)->raw_lock)
+# define _raw_read_unlock(rwlock) __raw_read_unlock(&(rwlock)->raw_lock)
+# define _raw_write_lock(rwlock) __raw_write_lock(&(rwlock)->raw_lock)
+# define _raw_write_lock_flags(lock, flags) \
+ __raw_write_lock_flags(&(lock)->raw_lock, *(flags))
+# define _raw_write_trylock(rwlock) __raw_write_trylock(&(rwlock)->raw_lock)
+# define _raw_write_unlock(rwlock) __raw_write_unlock(&(rwlock)->raw_lock)
+#endif
+
+#define read_can_lock(rwlock) __raw_read_can_lock(&(rwlock)->raw_lock)
+#define write_can_lock(rwlock) __raw_write_can_lock(&(rwlock)->raw_lock)
+
+/*
+ * Define the various rw_lock methods. Note we define these
+ * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various
+ * methods are defined as nops in the case they are not required.
+ */
+#define read_trylock(lock) __cond_lock(lock, _read_trylock(lock))
+#define write_trylock(lock) __cond_lock(lock, _write_trylock(lock))
+
+#define write_lock(lock) _write_lock(lock)
+#define read_lock(lock) _read_lock(lock)
+
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+
+#define read_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ flags = _read_lock_irqsave(lock); \
+ } while (0)
+#define write_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ flags = _write_lock_irqsave(lock); \
+ } while (0)
+
+#else
+
+#define read_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ _read_lock_irqsave(lock, flags); \
+ } while (0)
+#define write_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ _write_lock_irqsave(lock, flags); \
+ } while (0)
+
+#endif
+
+#define read_lock_irq(lock) _read_lock_irq(lock)
+#define read_lock_bh(lock) _read_lock_bh(lock)
+#define write_lock_irq(lock) _write_lock_irq(lock)
+#define write_lock_bh(lock) _write_lock_bh(lock)
+#define read_unlock(lock) _read_unlock(lock)
+#define write_unlock(lock) _write_unlock(lock)
+#define read_unlock_irq(lock) _read_unlock_irq(lock)
+#define write_unlock_irq(lock) _write_unlock_irq(lock)
+
+#define read_unlock_irqrestore(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ _read_unlock_irqrestore(lock, flags); \
+ } while (0)
+#define read_unlock_bh(lock) _read_unlock_bh(lock)
+
+#define write_unlock_irqrestore(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ _write_unlock_irqrestore(lock, flags); \
+ } while (0)
+#define write_unlock_bh(lock) _write_unlock_bh(lock)
+
+#define write_trylock_irqsave(lock, flags) \
+({ \
+ local_irq_save(flags); \
+ write_trylock(lock) ? \
+ 1 : ({ local_irq_restore(flags); 0; }); \
+})
+
+#endif /* __LINUX_RWLOCK_H */
Index: linux-2.6-tip/include/linux/rwlock_types.h
===================================================================
--- /dev/null
+++ linux-2.6-tip/include/linux/rwlock_types.h
@@ -0,0 +1,56 @@
+#ifndef __LINUX_RWLOCK_TYPES_H
+#define __LINUX_RWLOCK_TYPES_H
+
+/*
+ * include/linux/rwlock_types.h - generic rwlock type definitions
+ * and initializers
+ *
+ * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ */
+typedef struct {
+ raw_rwlock_t raw_lock;
+#ifdef CONFIG_GENERIC_LOCKBREAK
+ unsigned int break_lock;
+#endif
+#ifdef CONFIG_DEBUG_SPINLOCK
+ unsigned int magic, owner_cpu;
+ void *owner;
+#endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+} rwlock_t;
+
+#define RWLOCK_MAGIC 0xdeaf1eed
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RW_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname }
+#else
+# define RW_DEP_MAP_INIT(lockname)
+#endif
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+#define __RW_LOCK_UNLOCKED(lockname) \
+ (rwlock_t) { .raw_lock = __RAW_RW_LOCK_UNLOCKED, \
+ .magic = RWLOCK_MAGIC, \
+ .owner = SPINLOCK_OWNER_INIT, \
+ .owner_cpu = -1, \
+ RW_DEP_MAP_INIT(lockname) }
+#else
+#define __RW_LOCK_UNLOCKED(lockname) \
+ (rwlock_t) { .raw_lock = __RAW_RW_LOCK_UNLOCKED, \
+ RW_DEP_MAP_INIT(lockname) }
+#endif
+
+/*
+ * RW_LOCK_UNLOCKED defeat lockdep state tracking and is hence
+ * deprecated.
+ *
+ * Please use DEFINE_RWLOCK() or __RW_LOCK_UNLOCKED() as appropriate.
+ */
+#define RW_LOCK_UNLOCKED __RW_LOCK_UNLOCKED(old_style_rw_init)
+
+#define DEFINE_RWLOCK(x) rwlock_t x = __RW_LOCK_UNLOCKED(x)
+
+#endif /* __LINUX_RWLOCK_TYPES_H */
Index: linux-2.6-tip/include/linux/spinlock.h
===================================================================
--- linux-2.6-tip.orig/include/linux/spinlock.h
+++ linux-2.6-tip/include/linux/spinlock.h
@@ -103,20 +103,6 @@ do { \
do { *(lock) = __SPIN_LOCK_UNLOCKED(lock); } while (0)
#endif

-#ifdef CONFIG_DEBUG_SPINLOCK
- extern void __rwlock_init(rwlock_t *lock, const char *name,
- struct lock_class_key *key);
-# define rwlock_init(lock) \
-do { \
- static struct lock_class_key __key; \
- \
- __rwlock_init((lock), #lock, &__key); \
-} while (0)
-#else
-# define rwlock_init(lock) \
- do { *(lock) = __RW_LOCK_UNLOCKED(lock); } while (0)
-#endif
-
#define spin_is_locked(lock) __raw_spin_is_locked(&(lock)->raw_lock)

#ifdef CONFIG_GENERIC_LOCKBREAK
@@ -146,43 +132,21 @@ static inline void smp_mb__after_lock(vo
#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
extern int _raw_spin_trylock(spinlock_t *lock);
extern void _raw_spin_unlock(spinlock_t *lock);
- extern void _raw_read_lock(rwlock_t *lock);
-#define _raw_read_lock_flags(lock, flags) _raw_read_lock(lock)
- extern int _raw_read_trylock(rwlock_t *lock);
- extern void _raw_read_unlock(rwlock_t *lock);
- extern void _raw_write_lock(rwlock_t *lock);
-#define _raw_write_lock_flags(lock, flags) _raw_write_lock(lock)
- extern int _raw_write_trylock(rwlock_t *lock);
- extern void _raw_write_unlock(rwlock_t *lock);
#else
# define _raw_spin_lock(lock) __raw_spin_lock(&(lock)->raw_lock)
# define _raw_spin_lock_flags(lock, flags) \
__raw_spin_lock_flags(&(lock)->raw_lock, *(flags))
# define _raw_spin_trylock(lock) __raw_spin_trylock(&(lock)->raw_lock)
# define _raw_spin_unlock(lock) __raw_spin_unlock(&(lock)->raw_lock)
-# define _raw_read_lock(rwlock) __raw_read_lock(&(rwlock)->raw_lock)
-# define _raw_read_lock_flags(lock, flags) \
- __raw_read_lock_flags(&(lock)->raw_lock, *(flags))
-# define _raw_read_trylock(rwlock) __raw_read_trylock(&(rwlock)->raw_lock)
-# define _raw_read_unlock(rwlock) __raw_read_unlock(&(rwlock)->raw_lock)
-# define _raw_write_lock(rwlock) __raw_write_lock(&(rwlock)->raw_lock)
-# define _raw_write_lock_flags(lock, flags) \
- __raw_write_lock_flags(&(lock)->raw_lock, *(flags))
-# define _raw_write_trylock(rwlock) __raw_write_trylock(&(rwlock)->raw_lock)
-# define _raw_write_unlock(rwlock) __raw_write_unlock(&(rwlock)->raw_lock)
#endif

-#define read_can_lock(rwlock) __raw_read_can_lock(&(rwlock)->raw_lock)
-#define write_can_lock(rwlock) __raw_write_can_lock(&(rwlock)->raw_lock)
-
/*
- * Define the various spin_lock and rw_lock methods. Note we define these
- * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various
- * methods are defined as nops in the case they are not required.
+ * Define the various spin_lock methods. Note we define these
+ * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The
+ * various methods are defined as nops in the case they are not
+ * required.
*/
#define spin_trylock(lock) __cond_lock(lock, _spin_trylock(lock))
-#define read_trylock(lock) __cond_lock(lock, _read_trylock(lock))
-#define write_trylock(lock) __cond_lock(lock, _write_trylock(lock))

#define spin_lock(lock) _spin_lock(lock)

@@ -198,9 +162,6 @@ static inline void smp_mb__after_lock(vo
# define spin_lock_nest_lock(lock, nest_lock) _spin_lock(lock)
#endif

-#define write_lock(lock) _write_lock(lock)
-#define read_lock(lock) _read_lock(lock)
-
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)

#define spin_lock_irqsave(lock, flags) \
@@ -208,16 +169,6 @@ static inline void smp_mb__after_lock(vo
typecheck(unsigned long, flags); \
flags = _spin_lock_irqsave(lock); \
} while (0)
-#define read_lock_irqsave(lock, flags) \
- do { \
- typecheck(unsigned long, flags); \
- flags = _read_lock_irqsave(lock); \
- } while (0)
-#define write_lock_irqsave(lock, flags) \
- do { \
- typecheck(unsigned long, flags); \
- flags = _write_lock_irqsave(lock); \
- } while (0)

#ifdef CONFIG_DEBUG_LOCK_ALLOC
#define spin_lock_irqsave_nested(lock, flags, subclass) \
@@ -240,16 +191,7 @@ static inline void smp_mb__after_lock(vo
typecheck(unsigned long, flags); \
_spin_lock_irqsave(lock, flags); \
} while (0)
-#define read_lock_irqsave(lock, flags) \
- do { \
- typecheck(unsigned long, flags); \
- _read_lock_irqsave(lock, flags); \
- } while (0)
-#define write_lock_irqsave(lock, flags) \
- do { \
- typecheck(unsigned long, flags); \
- _write_lock_irqsave(lock, flags); \
- } while (0)
+
#define spin_lock_irqsave_nested(lock, flags, subclass) \
spin_lock_irqsave(lock, flags)

@@ -257,16 +199,8 @@ static inline void smp_mb__after_lock(vo

#define spin_lock_irq(lock) _spin_lock_irq(lock)
#define spin_lock_bh(lock) _spin_lock_bh(lock)
-#define read_lock_irq(lock) _read_lock_irq(lock)
-#define read_lock_bh(lock) _read_lock_bh(lock)
-#define write_lock_irq(lock) _write_lock_irq(lock)
-#define write_lock_bh(lock) _write_lock_bh(lock)
#define spin_unlock(lock) _spin_unlock(lock)
-#define read_unlock(lock) _read_unlock(lock)
-#define write_unlock(lock) _write_unlock(lock)
#define spin_unlock_irq(lock) _spin_unlock_irq(lock)
-#define read_unlock_irq(lock) _read_unlock_irq(lock)
-#define write_unlock_irq(lock) _write_unlock_irq(lock)

#define spin_unlock_irqrestore(lock, flags) \
do { \
@@ -275,20 +209,6 @@ static inline void smp_mb__after_lock(vo
} while (0)
#define spin_unlock_bh(lock) _spin_unlock_bh(lock)

-#define read_unlock_irqrestore(lock, flags) \
- do { \
- typecheck(unsigned long, flags); \
- _read_unlock_irqrestore(lock, flags); \
- } while (0)
-#define read_unlock_bh(lock) _read_unlock_bh(lock)
-
-#define write_unlock_irqrestore(lock, flags) \
- do { \
- typecheck(unsigned long, flags); \
- _write_unlock_irqrestore(lock, flags); \
- } while (0)
-#define write_unlock_bh(lock) _write_unlock_bh(lock)
-
#define spin_trylock_bh(lock) __cond_lock(lock, _spin_trylock_bh(lock))

#define spin_trylock_irq(lock) \
@@ -305,13 +225,6 @@ static inline void smp_mb__after_lock(vo
1 : ({ local_irq_restore(flags); 0; }); \
})

-#define write_trylock_irqsave(lock, flags) \
-({ \
- local_irq_save(flags); \
- write_trylock(lock) ? \
- 1 : ({ local_irq_restore(flags); 0; }); \
-})
-
/*
* Pull the atomic_t declaration:
* (asm-mips/atomic.h needs above definitions)
@@ -335,6 +248,9 @@ extern int _atomic_dec_and_lock(atomic_t
*/
#define spin_can_lock(lock) (!spin_is_locked(lock))

+/* Include rwlock functions */
+#include <linux/rwlock.h>
+
/*
* Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
*/
Index: linux-2.6-tip/include/linux/spinlock_types.h
===================================================================
--- linux-2.6-tip.orig/include/linux/spinlock_types.h
+++ linux-2.6-tip/include/linux/spinlock_types.h
@@ -33,22 +33,6 @@ typedef struct {

#define SPINLOCK_MAGIC 0xdead4ead

-typedef struct {
- raw_rwlock_t raw_lock;
-#ifdef CONFIG_GENERIC_LOCKBREAK
- unsigned int break_lock;
-#endif
-#ifdef CONFIG_DEBUG_SPINLOCK
- unsigned int magic, owner_cpu;
- void *owner;
-#endif
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map dep_map;
-#endif
-} rwlock_t;
-
-#define RWLOCK_MAGIC 0xdeaf1eed
-
#define SPINLOCK_OWNER_INIT ((void *)-1L)

#ifdef CONFIG_DEBUG_LOCK_ALLOC
@@ -57,12 +41,6 @@ typedef struct {
# define SPIN_DEP_MAP_INIT(lockname)
#endif

-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define RW_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname }
-#else
-# define RW_DEP_MAP_INIT(lockname)
-#endif
-
#ifdef CONFIG_DEBUG_SPINLOCK
# define __SPIN_LOCK_UNLOCKED(lockname) \
(spinlock_t) { .raw_lock = __RAW_SPIN_LOCK_UNLOCKED, \
@@ -70,31 +48,22 @@ typedef struct {
.owner = SPINLOCK_OWNER_INIT, \
.owner_cpu = -1, \
SPIN_DEP_MAP_INIT(lockname) }
-#define __RW_LOCK_UNLOCKED(lockname) \
- (rwlock_t) { .raw_lock = __RAW_RW_LOCK_UNLOCKED, \
- .magic = RWLOCK_MAGIC, \
- .owner = SPINLOCK_OWNER_INIT, \
- .owner_cpu = -1, \
- RW_DEP_MAP_INIT(lockname) }
#else
# define __SPIN_LOCK_UNLOCKED(lockname) \
(spinlock_t) { .raw_lock = __RAW_SPIN_LOCK_UNLOCKED, \
SPIN_DEP_MAP_INIT(lockname) }
-#define __RW_LOCK_UNLOCKED(lockname) \
- (rwlock_t) { .raw_lock = __RAW_RW_LOCK_UNLOCKED, \
- RW_DEP_MAP_INIT(lockname) }
#endif

/*
- * SPIN_LOCK_UNLOCKED and RW_LOCK_UNLOCKED defeat lockdep state tracking and
- * are hence deprecated.
- * Please use DEFINE_SPINLOCK()/DEFINE_RWLOCK() or
- * __SPIN_LOCK_UNLOCKED()/__RW_LOCK_UNLOCKED() as appropriate.
+ * SPIN_LOCK_UNLOCKED defeats lockdep state tracking and is hence
+ * deprecated.
+ * Please use DEFINE_SPINLOCK() or __SPIN_LOCK_UNLOCKED() as
+ * appropriate.
*/
#define SPIN_LOCK_UNLOCKED __SPIN_LOCK_UNLOCKED(old_style_spin_init)
-#define RW_LOCK_UNLOCKED __RW_LOCK_UNLOCKED(old_style_rw_init)

#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
-#define DEFINE_RWLOCK(x) rwlock_t x = __RW_LOCK_UNLOCKED(x)
+
+#include <linux/rwlock_types.h>

#endif /* __LINUX_SPINLOCK_TYPES_H */


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