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#ifndef __LINUX_SPINLOCK_H
#define __LINUX_SPINLOCK_H
/*
* include/linux/spinlock.h - generic locking declarations
*/
#include <linux/config.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 <asm/system.h>
/*
* Must define these before including other files, inline functions need them
*/
#define LOCK_SECTION_NAME \
".text.lock." __stringify(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\t"
#define LOCK_SECTION_END \
".previous\n\t"
/*
* If CONFIG_SMP is set, pull in the _raw_* definitions
*/
#ifdef CONFIG_SMP
#include <asm/spinlock.h>
/*
* !CONFIG_SMP and spin_lock_init not previously defined
* (e.g. by including include/asm/spinlock.h)
*/
#elif !defined(spin_lock_init)
#ifndef CONFIG_PREEMPT
# define atomic_dec_and_lock(atomic,lock) atomic_dec_and_test(atomic)
# define ATOMIC_DEC_AND_LOCK
#endif
/*
* gcc versions before ~2.95 have a nasty bug with empty initializers.
*/
#if (__GNUC__ > 2)
typedef struct { } spinlock_t;
typedef struct { } rwlock_t;
#define SPIN_LOCK_UNLOCKED (spinlock_t) { }
#define RW_LOCK_UNLOCKED (rwlock_t) { }
#else
typedef struct { int gcc_is_buggy; } spinlock_t;
typedef struct { int gcc_is_buggy; } rwlock_t;
#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
#define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
#endif
/*
* If CONFIG_SMP is unset, declare the _raw_* definitions as nops
*/
#define spin_lock_init(lock) do { (void)(lock); } while(0)
#define _raw_spin_lock(lock) do { (void)(lock); } while(0)
#define spin_is_locked(lock) ((void)(lock), 0)
#define _raw_spin_trylock(lock) ((void)(lock), 1)
#define spin_unlock_wait(lock) do { (void)(lock); } while(0)
#define _raw_spin_unlock(lock) do { (void)(lock); } while(0)
#define rwlock_init(lock) do { (void)(lock); } while(0)
#define _raw_read_lock(lock) do { (void)(lock); } while(0)
#define _raw_read_unlock(lock) do { (void)(lock); } while(0)
#define _raw_write_lock(lock) do { (void)(lock); } while(0)
#define _raw_write_unlock(lock) do { (void)(lock); } while(0)
#endif /* !SMP */
/*
* 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_lock(lock) \
do { \
preempt_disable(); \
_raw_spin_lock(lock); \
} while(0)
#define spin_trylock(lock) ({preempt_disable(); _raw_spin_trylock(lock) ? \
1 : ({preempt_enable(); 0;});})
#define spin_unlock(lock) \
do { \
_raw_spin_unlock(lock); \
preempt_enable(); \
} while (0)
#define read_lock(lock) \
do { \
preempt_disable(); \
_raw_read_lock(lock); \
} while(0)
#define read_unlock(lock) \
do { \
_raw_read_unlock(lock); \
preempt_enable(); \
} while(0)
#define write_lock(lock) \
do { \
preempt_disable(); \
_raw_write_lock(lock); \
} while(0)
#define write_unlock(lock) \
do { \
_raw_write_unlock(lock); \
preempt_enable(); \
} while(0)
#define write_trylock(lock) ({preempt_disable();_raw_write_trylock(lock) ? \
1 : ({preempt_enable(); 0;});})
#define spin_lock_irqsave(lock, flags) \
do { \
local_irq_save(flags); \
preempt_disable(); \
_raw_spin_lock(lock); \
} while (0)
#define spin_lock_irq(lock) \
do { \
local_irq_disable(); \
preempt_disable(); \
_raw_spin_lock(lock); \
} while (0)
#define spin_lock_bh(lock) \
do { \
local_bh_disable(); \
preempt_disable(); \
_raw_spin_lock(lock); \
} while (0)
#define read_lock_irqsave(lock, flags) \
do { \
local_irq_save(flags); \
preempt_disable(); \
_raw_read_lock(lock); \
} while (0)
#define read_lock_irq(lock) \
do { \
local_irq_disable(); \
preempt_disable(); \
_raw_read_lock(lock); \
} while (0)
#define read_lock_bh(lock) \
do { \
local_bh_disable(); \
preempt_disable(); \
_raw_read_lock(lock); \
} while (0)
#define write_lock_irqsave(lock, flags) \
do { \
local_irq_save(flags); \
preempt_disable(); \
_raw_write_lock(lock); \
} while (0)
#define write_lock_irq(lock) \
do { \
local_irq_disable(); \
preempt_disable(); \
_raw_write_lock(lock); \
} while (0)
#define write_lock_bh(lock) \
do { \
local_bh_disable(); \
preempt_disable(); \
_raw_write_lock(lock); \
} while (0)
#define spin_unlock_irqrestore(lock, flags) \
do { \
_raw_spin_unlock(lock); \
local_irq_restore(flags); \
preempt_enable(); \
} while (0)
#define _raw_spin_unlock_irqrestore(lock, flags) \
do { \
_raw_spin_unlock(lock); \
local_irq_restore(flags); \
} while (0)
#define spin_unlock_irq(lock) \
do { \
_raw_spin_unlock(lock); \
local_irq_enable(); \
preempt_enable(); \
} while (0)
#define spin_unlock_bh(lock) \
do { \
_raw_spin_unlock(lock); \
preempt_enable(); \
local_bh_enable(); \
} while (0)
#define read_unlock_irqrestore(lock, flags) \
do { \
_raw_read_unlock(lock); \
local_irq_restore(flags); \
preempt_enable(); \
} while (0)
#define read_unlock_irq(lock) \
do { \
_raw_read_unlock(lock); \
local_irq_enable(); \
preempt_enable(); \
} while (0)
#define read_unlock_bh(lock) \
do { \
_raw_read_unlock(lock); \
preempt_enable(); \
local_bh_enable(); \
} while (0)
#define write_unlock_irqrestore(lock, flags) \
do { \
_raw_write_unlock(lock); \
local_irq_restore(flags); \
preempt_enable(); \
} while (0)
#define write_unlock_irq(lock) \
do { \
_raw_write_unlock(lock); \
local_irq_enable(); \
preempt_enable(); \
} while (0)
#define write_unlock_bh(lock) \
do { \
_raw_write_unlock(lock); \
preempt_enable(); \
local_bh_enable(); \
} while (0)
#define spin_trylock_bh(lock) ({ local_bh_disable(); preempt_disable(); \
_raw_spin_trylock(lock) ? 1 : \
({preempt_enable(); local_bh_enable(); 0;});})
/* "lock on reference count zero" */
#ifndef ATOMIC_DEC_AND_LOCK
#include <asm/atomic.h>
extern int atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
#endif
#endif /* __LINUX_SPINLOCK_H */
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