/* [<][>][^][v][top][bottom][index][help] */
#ifndef __LINUX_SPINLOCK_H
#define __LINUX_SPINLOCK_H
/*
* include/linux/spinlock.h - generic spinlock/rwlock declarations
*
* here's the role of the various spinlock/rwlock related include files:
*
* on SMP builds:
*
* asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
* initializers
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel
* implementations, mostly inline assembly code
*
* (also included on UP-debug builds:)
*
* linux/spinlock_api_smp.h:
* contains the prototypes for the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*
* on UP builds:
*
* linux/spinlock_type_up.h:
* contains the generic, simplified UP spinlock type.
* (which is an empty structure on non-debug builds)
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* linux/spinlock_up.h:
* contains the __raw_spin_*()/etc. version of UP
* builds. (which are NOPs on non-debug, non-preempt
* builds)
*
* (included on UP-non-debug builds:)
*
* linux/spinlock_api_up.h:
* builds the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*/
#include <linux/typecheck.h>
#include <linux/preempt.h>
#include <linux/linkage.h>
#include <linux/compiler.h>
#include <linux/thread_info.h>
#include <linux/kernel.h>
#include <linux/stringify.h>
#include <linux/bottom_half.h>
#include <asm/system.h>
/*
* Must define these before including other files, inline functions need them
*/
#define LOCK_SECTION_NAME ".text.lock."KBUILD_BASENAME
#define LOCK_SECTION_START(extra) \
".subsection 1\n\t" \
extra \
".ifndef " LOCK_SECTION_NAME "\n\t" \
LOCK_SECTION_NAME ":\n\t" \
".endif\n"
#define LOCK_SECTION_END \
".previous\n\t"
#define __lockfunc __attribute__((section(".spinlock.text")))
/*
* Pull the raw_spinlock_t and raw_rwlock_t definitions:
*/
#include <linux/spinlock_types.h>
extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);
/*
* Pull the __raw*() functions/declarations (UP-nondebug doesnt need them):
*/
#ifdef CONFIG_SMP
# include <asm/spinlock.h>
#else
# include <linux/spinlock_up.h>
#endif
#ifdef CONFIG_DEBUG_SPINLOCK
extern void __spin_lock_init(spinlock_t *lock, const char *name,
struct lock_class_key *key);
# define spin_lock_init(lock) \
do { \
static struct lock_class_key __key; \
\
__spin_lock_init((lock), #lock, &__key); \
} while (0)
#else
# define spin_lock_init(lock) \
do { *(lock) = SPIN_LOCK_UNLOCKED; } 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; } while (0)
#endif
#define spin_is_locked(lock) __raw_spin_is_locked(&(lock)->raw_lock)
#ifdef CONFIG_GENERIC_LOCKBREAK
#define spin_is_contended(lock) ((lock)->break_lock)
#else
#define spin_is_contended(lock) __raw_spin_is_contended(&(lock)->raw_lock)
#endif
/**
* spin_unlock_wait - wait until the spinlock gets unlocked
* @lock: the spinlock in question.
*/
#define spin_unlock_wait(lock) __raw_spin_unlock_wait(&(lock)->raw_lock)
/*
* Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
*/
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
# include <linux/spinlock_api_smp.h>
#else
# include <linux/spinlock_api_up.h>
#endif
#ifdef CONFIG_DEBUG_SPINLOCK
extern void _raw_spin_lock(spinlock_t *lock);
#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);
extern int _raw_read_trylock(rwlock_t *lock);
extern void _raw_read_unlock(rwlock_t *lock);
extern void _raw_write_lock(rwlock_t *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_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_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 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)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define spin_lock_nested(lock, subclass) _spin_lock_nested(lock, subclass)
# define spin_lock_nest_lock(lock, nest_lock) \
do { \
typecheck(struct lockdep_map *, &(nest_lock)->dep_map);\
_spin_lock_nest_lock(lock, &(nest_lock)->dep_map); \
} while (0)
#else
# define spin_lock_nested(lock, subclass) _spin_lock(lock)
# 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) \
do { \
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) \
do { \
typecheck(unsigned long, flags); \
flags = _spin_lock_irqsave_nested(lock, subclass); \
} while (0)
#else
#define spin_lock_irqsave_nested(lock, flags, subclass) \
do { \
typecheck(unsigned long, flags); \
flags = _spin_lock_irqsave(lock); \
} while (0)
#endif
#else
#define spin_lock_irqsave(lock, flags) \
do { \
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)
#endif
#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)
/*
* We inline the unlock functions in the nondebug case:
*/
#if defined(CONFIG_DEBUG_SPINLOCK) || defined(CONFIG_PREEMPT) || \
!defined(CONFIG_SMP)
# 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)
#else
# define spin_unlock(lock) \
do {__raw_spin_unlock(&(lock)->raw_lock); __release(lock); } while (0)
# define read_unlock(lock) \
do {__raw_read_unlock(&(lock)->raw_lock); __release(lock); } while (0)
# define write_unlock(lock) \
do {__raw_write_unlock(&(lock)->raw_lock); __release(lock); } while (0)
# define spin_unlock_irq(lock) \
do { \
__raw_spin_unlock(&(lock)->raw_lock); \
__release(lock); \
local_irq_enable(); \
} while (0)
# define read_unlock_irq(lock) \
do { \
__raw_read_unlock(&(lock)->raw_lock); \
__release(lock); \
local_irq_enable(); \
} while (0)
# define write_unlock_irq(lock) \
do { \
__raw_write_unlock(&(lock)->raw_lock); \
__release(lock); \
local_irq_enable(); \
} while (0)
#endif
#define spin_unlock_irqrestore(lock, flags) \
do { \
typecheck(unsigned long, flags); \
_spin_unlock_irqrestore(lock, flags); \
} 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) \
({ \
local_irq_disable(); \
spin_trylock(lock) ? \
1 : ({ local_irq_enable(); 0; }); \
})
#define spin_trylock_irqsave(lock, flags) \
({ \
local_irq_save(flags); \
spin_trylock(lock) ? \
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)
*/
#include <asm/atomic.h>
/**
* atomic_dec_and_lock - lock on reaching reference count zero
* @atomic: the atomic counter
* @lock: the spinlock in question
*
* Decrements @atomic by 1. If the result is 0, returns true and locks
* @lock. Returns false for all other cases.
*/
extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
#define atomic_dec_and_lock(atomic, lock) \
__cond_lock(lock, _atomic_dec_and_lock(atomic, lock))
/**
* spin_can_lock - would spin_trylock() succeed?
* @lock: the spinlock in question.
*/
#define spin_can_lock(lock) (!spin_is_locked(lock))
#endif /* __LINUX_SPINLOCK_H */