diff options
Diffstat (limited to 'libpthread/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h')
| -rw-r--r-- | libpthread/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h | 284 | 
1 files changed, 284 insertions, 0 deletions
| diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h b/libpthread/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h new file mode 100644 index 000000000..b7f4de338 --- /dev/null +++ b/libpthread/nptl/sysdeps/unix/sysv/linux/alpha/lowlevellock.h @@ -0,0 +1,284 @@ +/* Copyright (C) 2003, 2004, 2006, 2007 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 +   modify it under the terms of the GNU Lesser General Public +   License as published by the Free Software Foundation; either +   version 2.1 of the License, or (at your option) any later version. + +   The GNU C Library is distributed in the hope that it will be useful, +   but WITHOUT ANY WARRANTY; without even the implied warranty of +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU +   Lesser General Public License for more details. + +   You should have received a copy of the GNU Lesser General Public +   License along with the GNU C Libr	\ary; if not, write to the Free +   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA +   02111-1307 USA.  */ + +#ifndef _LOWLEVELLOCK_H +#define _LOWLEVELLOCK_H	1 + +#include <time.h> +#include <sys/param.h> +#include <bits/pthreadtypes.h> +#include <atomic.h> +#include <sysdep.h> +#include <bits/kernel-features.h> + + +#define FUTEX_WAIT		0 +#define FUTEX_WAKE		1 +#define FUTEX_REQUEUE		3 +#define FUTEX_CMP_REQUEUE	4 +#define FUTEX_WAKE_OP		5 +#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1) +#define FUTEX_LOCK_PI		6 +#define FUTEX_UNLOCK_PI		7 +#define FUTEX_TRYLOCK_PI	8 +#define FUTEX_WAIT_BITSET	9 +#define FUTEX_WAKE_BITSET	10 +#define FUTEX_PRIVATE_FLAG	128 +#define FUTEX_CLOCK_REALTIME	256 + +#define FUTEX_BITSET_MATCH_ANY	0xffffffff + +/* Values for 'private' parameter of locking macros.  Yes, the +   definition seems to be backwards.  But it is not.  The bit will be +   reversed before passing to the system call.  */ +#define LLL_PRIVATE	0 +#define LLL_SHARED	FUTEX_PRIVATE_FLAG + + +#if !defined NOT_IN_libc || defined IS_IN_rtld +/* In libc.so or ld.so all futexes are private.  */ +# ifdef __ASSUME_PRIVATE_FUTEX +#  define __lll_private_flag(fl, private) \ +  ((fl) | FUTEX_PRIVATE_FLAG) +# else +#  define __lll_private_flag(fl, private) \ +  ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex)) +# endif +#else +# ifdef __ASSUME_PRIVATE_FUTEX +#  define __lll_private_flag(fl, private) \ +  (((fl) | FUTEX_PRIVATE_FLAG) ^ (private)) +# else +#  define __lll_private_flag(fl, private) \ +  (__builtin_constant_p (private)					      \ +   ? ((private) == 0							      \ +      ? ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex))	      \ +      : (fl))								      \ +   : ((fl) | (((private) ^ FUTEX_PRIVATE_FLAG)				      \ +	      & THREAD_GETMEM (THREAD_SELF, header.private_futex)))) +# endif	       +#endif + + +#define lll_futex_wait(futexp, val, private) \ +  lll_futex_timed_wait (futexp, val, NULL, private) + +#define lll_futex_timed_wait(futexp, val, timespec, private) \ +  ({									      \ +    INTERNAL_SYSCALL_DECL (__err);					      \ +    long int __ret;							      \ +    __ret = INTERNAL_SYSCALL (futex, __err, 4, (futexp),		      \ +			      __lll_private_flag (FUTEX_WAIT, private),	      \ +			      (val), (timespec));			      \ +    INTERNAL_SYSCALL_ERROR_P (__ret, __err)? -__ret : __ret;		      \ +  }) + +#define lll_futex_wake(futexp, nr, private) \ +  ({									      \ +    INTERNAL_SYSCALL_DECL (__err);					      \ +    long int __ret;							      \ +    __ret = INTERNAL_SYSCALL (futex, __err, 4, (futexp),		      \ +			      __lll_private_flag (FUTEX_WAKE, private),	      \ +			      (nr), 0);					      \ +    INTERNAL_SYSCALL_ERROR_P (__ret, __err)? -__ret : __ret;		      \ +  }) + +#define lll_robust_dead(futexv, private) \ +  do									      \ +    {									      \ +      int *__futexp = &(futexv);					      \ +      atomic_or (__futexp, FUTEX_OWNER_DIED);				      \ +      lll_futex_wake (__futexp, 1, private);				      \ +    }									      \ +  while (0) + +/* Returns non-zero if error happened, zero if success.  */ +#define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val, private) \ +  ({									      \ +    INTERNAL_SYSCALL_DECL (__err);					      \ +    long int __ret;							      \ +    __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp),		      \ +			      __lll_private_flag (FUTEX_CMP_REQUEUE, private),\ +			      (nr_wake), (nr_move), (mutex), (val));	      \ +    INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \ +  }) + +/* Returns non-zero if error happened, zero if success.  */ +#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \ +  ({									      \ +    INTERNAL_SYSCALL_DECL (__err);					      \ +    long int __ret;							      \ +    __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp),		      \ +			      __lll_private_flag (FUTEX_WAKE_OP, private),    \ +			      (nr_wake), (nr_wake2), (futexp2),		      \ +			      FUTEX_OP_CLEAR_WAKE_IF_GT_ONE);		      \ +    INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \ +  }) + + + + +static inline int __attribute__((always_inline)) +__lll_trylock(int *futex) +{ +  return atomic_compare_and_exchange_val_acq (futex, 1, 0) != 0; +} +#define lll_trylock(lock)	__lll_trylock (&(lock)) + + +static inline int __attribute__((always_inline)) +__lll_cond_trylock(int *futex) +{ +  return atomic_compare_and_exchange_val_acq (futex, 2, 0) != 0; +} +#define lll_cond_trylock(lock)	__lll_cond_trylock (&(lock)) + + +static inline int __attribute__((always_inline)) +__lll_robust_trylock(int *futex, int id) +{ +  return atomic_compare_and_exchange_val_acq (futex, id, 0) != 0; +} +#define lll_robust_trylock(lock, id) \ +  __lll_robust_trylock (&(lock), id) + +extern void __lll_lock_wait_private (int *futex) attribute_hidden; +extern void __lll_lock_wait (int *futex, int private) attribute_hidden; +extern int __lll_robust_lock_wait (int *futex, int private) attribute_hidden; + +static inline void __attribute__((always_inline)) +__lll_lock(int *futex, int private) +{ +  if (atomic_compare_and_exchange_bool_acq (futex, 1, 0) != 0) +    { +      if (__builtin_constant_p (private) && private == LLL_PRIVATE) +	__lll_lock_wait_private (futex); +      else +	__lll_lock_wait (futex, private); +    } +} +#define lll_lock(futex, private) __lll_lock (&(futex), private) + + +static inline int __attribute__ ((always_inline)) +__lll_robust_lock (int *futex, int id, int private) +{ +  int result = 0; +  if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0) +    result = __lll_robust_lock_wait (futex, private); +  return result; +} +#define lll_robust_lock(futex, id, private) \ +  __lll_robust_lock (&(futex), id, private) + + +static inline void __attribute__ ((always_inline)) +__lll_cond_lock (int *futex, int private) +{ +  if (atomic_compare_and_exchange_bool_acq (futex, 2, 0) != 0) +    __lll_lock_wait (futex, private); +} +#define lll_cond_lock(futex, private) __lll_cond_lock (&(futex), private) + + +#define lll_robust_cond_lock(futex, id, private) \ +  __lll_robust_lock (&(futex), (id) | FUTEX_WAITERS, private) + + +extern int __lll_timedlock_wait (int *futex, const struct timespec *, +				 int private) attribute_hidden; +extern int __lll_robust_timedlock_wait (int *futex, const struct timespec *, +					int private) attribute_hidden; + +static inline int __attribute__ ((always_inline)) +__lll_timedlock (int *futex, const struct timespec *abstime, int private) +{ +  int result = 0; +  if (atomic_compare_and_exchange_bool_acq (futex, 1, 0) != 0) +    result = __lll_timedlock_wait (futex, abstime, private); +  return result; +} +#define lll_timedlock(futex, abstime, private) \ +  __lll_timedlock (&(futex), abstime, private) + + +static inline int __attribute__ ((always_inline)) +__lll_robust_timedlock (int *futex, const struct timespec *abstime, +			int id, int private) +{ +  int result = 0; +  if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0) +    result = __lll_robust_timedlock_wait (futex, abstime, private); +  return result; +} +#define lll_robust_timedlock(futex, abstime, id, private) \ +  __lll_robust_timedlock (&(futex), abstime, id, private) + + +#define __lll_unlock(futex, private) \ +  (void)							\ +    ({ int *__futex = (futex);					\ +       int __oldval = atomic_exchange_rel (__futex, 0);		\ +       if (__builtin_expect (__oldval > 1, 0))			\ +	 lll_futex_wake (__futex, 1, private);			\ +    }) +#define lll_unlock(futex, private) __lll_unlock(&(futex), private) + + +#define __lll_robust_unlock(futex, private) \ +  (void)							\ +    ({ int *__futex = (futex);					\ +       int __oldval = atomic_exchange_rel (__futex, 0);		\ +       if (__builtin_expect (__oldval & FUTEX_WAITERS, 0))	\ +	 lll_futex_wake (__futex, 1, private);			\ +    }) +#define lll_robust_unlock(futex, private) \ +  __lll_robust_unlock(&(futex), private) + + +#define lll_islocked(futex) \ +  (futex != 0) + +/* Initializers for lock.  */ +#define LLL_LOCK_INITIALIZER		(0) +#define LLL_LOCK_INITIALIZER_LOCKED	(1) + + +/* The kernel notifies a process which uses CLONE_CLEARTID via futex +   wakeup when the clone terminates.  The memory location contains the +   thread ID while the clone is running and is reset to zero +   afterwards.	*/ +#define lll_wait_tid(tid) \ +  do {							\ +    __typeof (tid) __tid;				\ +    while ((__tid = (tid)) != 0)			\ +      lll_futex_wait (&(tid), __tid, LLL_SHARED);	\ +  } while (0) + +extern int __lll_timedwait_tid (int *, const struct timespec *) +     attribute_hidden; + +#define lll_timedwait_tid(tid, abstime) \ +  ({							\ +    int __res = 0;					\ +    if ((tid) != 0)					\ +      __res = __lll_timedwait_tid (&(tid), (abstime));	\ +    __res;						\ +  }) + +#endif	/* lowlevellock.h */ | 
