| #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> |
| |
| /* |
| * 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(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 |
| #define spin_is_contended(lock) ((lock)->break_lock) |
| #else |
| |
| #ifdef __raw_spin_is_contended |
| #define spin_is_contended(lock) __raw_spin_is_contended(&(lock)->raw_lock) |
| #else |
| #define spin_is_contended(lock) (((void)(lock), 0)) |
| #endif /*__raw_spin_is_contended*/ |
| #endif |
| |
| /* The lock does not imply full memory barrier. */ |
| #ifndef ARCH_HAS_SMP_MB_AFTER_LOCK |
| static inline void smp_mb__after_lock(void) { smp_mb(); } |
| #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) |
| |
| #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); |
| #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 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) |
| #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 { \ |
| 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)) |
| |
| /* |
| * 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 |
| |
| #endif /* __LINUX_SPINLOCK_H */ |