diff options
Diffstat (limited to 'mach/lock-intern.h')
| -rw-r--r-- | mach/lock-intern.h | 91 |
1 files changed, 66 insertions, 25 deletions
diff --git a/mach/lock-intern.h b/mach/lock-intern.h index 426628b9c2..ed8acb6aec 100644 --- a/mach/lock-intern.h +++ b/mach/lock-intern.h @@ -1,4 +1,4 @@ -/* Copyright (C) 1994-2016 Free Software Foundation, Inc. +/* Copyright (C) 1994-2018 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -19,20 +19,31 @@ #define _LOCK_INTERN_H #include <sys/cdefs.h> -#include <machine-lock.h> +#if defined __USE_EXTERN_INLINES && defined _LIBC +# include <lowlevellock.h> +#endif #ifndef _EXTERN_INLINE #define _EXTERN_INLINE __extern_inline #endif +/* The type of a spin lock variable. */ +typedef unsigned int __spin_lock_t; + +/* Static initializer for spinlocks. */ +#define __SPIN_LOCK_INITIALIZER LLL_INITIALIZER /* Initialize LOCK. */ +extern void __spin_lock_init (__spin_lock_t *__lock); + +#if defined __USE_EXTERN_INLINES && defined _LIBC _EXTERN_INLINE void __spin_lock_init (__spin_lock_t *__lock) { *__lock = __SPIN_LOCK_INITIALIZER; } +#endif /* Lock LOCK, blocking if we can't get it. */ @@ -40,57 +51,87 @@ extern void __spin_lock_solid (__spin_lock_t *__lock); /* Lock the spin lock LOCK. */ +extern void __spin_lock (__spin_lock_t *__lock); + +#if defined __USE_EXTERN_INLINES && defined _LIBC _EXTERN_INLINE void __spin_lock (__spin_lock_t *__lock) { - if (! __spin_try_lock (__lock)) - __spin_lock_solid (__lock); + lll_lock (__lock, 0); } - -/* Name space-clean internal interface to mutex locks. +#endif - Code internal to the C library uses these functions to lock and unlock - mutex locks. These locks are of type `struct mutex', defined in - <cthreads.h>. The functions here are name space-clean. If the program - is linked with the cthreads library, `__mutex_lock_solid' and - `__mutex_unlock_solid' will invoke the corresponding cthreads functions - to implement real mutex locks. If not, simple stub versions just use - spin locks. */ +/* Unlock LOCK. */ +extern void __spin_unlock (__spin_lock_t *__lock); +#if defined __USE_EXTERN_INLINES && defined _LIBC +_EXTERN_INLINE void +__spin_unlock (__spin_lock_t *__lock) +{ + lll_unlock (__lock, 0); +} +#endif -/* Initialize the newly allocated mutex lock LOCK for further use. */ -extern void __mutex_init (void *__lock); +/* Try to lock LOCK; return nonzero if we locked it, zero if another has. */ +extern int __spin_try_lock (__spin_lock_t *__lock); -/* Lock LOCK, blocking if we can't get it. */ -extern void __mutex_lock_solid (void *__lock); +#if defined __USE_EXTERN_INLINES && defined _LIBC +_EXTERN_INLINE int +__spin_try_lock (__spin_lock_t *__lock) +{ + return (lll_trylock (__lock) == 0); +} +#endif + +/* Return nonzero if LOCK is locked. */ +extern int __spin_lock_locked (__spin_lock_t *__lock); + +#if defined __USE_EXTERN_INLINES && defined _LIBC +_EXTERN_INLINE int +__spin_lock_locked (__spin_lock_t *__lock) +{ + return (*(volatile __spin_lock_t *)__lock != 0); +} +#endif + +/* Name space-clean internal interface to mutex locks. */ -/* Finish unlocking LOCK, after the spin lock LOCK->held has already been - unlocked. This function will wake up any thread waiting on LOCK. */ -extern void __mutex_unlock_solid (void *__lock); +/* Initialize the newly allocated mutex lock LOCK for further use. */ +extern void __mutex_init (void *__lock); /* Lock the mutex lock LOCK. */ +extern void __mutex_lock (void *__lock); + +#if defined __USE_EXTERN_INLINES && defined _LIBC _EXTERN_INLINE void __mutex_lock (void *__lock) { - if (! __spin_try_lock ((__spin_lock_t *) __lock)) - __mutex_lock_solid (__lock); + __spin_lock ((__spin_lock_t *)__lock); } +#endif /* Unlock the mutex lock LOCK. */ +extern void __mutex_unlock (void *__lock); + +#if defined __USE_EXTERN_INLINES && defined _LIBC _EXTERN_INLINE void __mutex_unlock (void *__lock) { - __spin_unlock ((__spin_lock_t *) __lock); - __mutex_unlock_solid (__lock); + __spin_unlock ((__spin_lock_t *)__lock); } +#endif +extern int __mutex_trylock (void *__lock); + +#if defined __USE_EXTERN_INLINES && defined _LIBC _EXTERN_INLINE int __mutex_trylock (void *__lock) { - return __spin_try_lock ((__spin_lock_t *) __lock); + return (__spin_try_lock ((__spin_lock_t *)__lock)); } +#endif #endif /* lock-intern.h */ |