/* Copyright (C) 2003, 2004, 2006, 2007 Free Software Foundation, Inc.   This file is part of the GNU C Library.   Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.   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 <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_PRIVATE_FLAG	128/* 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));			      \    __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);					      \    __ret;								      \  })/* 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);				      \  })#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.  */#ifdef __sparc32_atomic_do_lock/* Avoid FUTEX_WAKE_OP if supporting pre-v9 CPUs.  */# define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2) 1#else# 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);				      \  })#endifstatic inline int__attribute__ ((always_inline))__lll_trylock (int *futex){  return atomic_compare_and_exchange_val_24_acq (futex, 1, 0) != 0;}#define lll_trylock(futex) __lll_trylock (&(futex))static inline int__attribute__ ((always_inline))__lll_cond_trylock (int *futex){  return atomic_compare_and_exchange_val_24_acq (futex, 2, 0) != 0;}#define lll_cond_trylock(futex) __lll_cond_trylock (&(futex))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(futex, id) \  __lll_robust_trylock (&(futex), 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){  int val = atomic_compare_and_exchange_val_24_acq (futex, 1, 0);  if (__builtin_expect (val != 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){  int val = atomic_compare_and_exchange_val_24_acq (futex, 2, 0);  if (__builtin_expect (val != 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 val = atomic_compare_and_exchange_val_24_acq (futex, 1, 0);  int result = 0;  if (__builtin_expect (val != 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(lock, private) \  ((void) ({								      \    int *__futex = &(lock);						      \    int __val = atomic_exchange_24_rel (__futex, 0);			      \    if (__builtin_expect (__val > 1, 0))				      \      lll_futex_wake (__futex, 1, private);				      \  }))#define lll_robust_unlock(lock, private) \  ((void) ({								      \    int *__futex = &(lock);						      \    int __val = atomic_exchange_rel (__futex, 0);			      \    if (__builtin_expect (__val & FUTEX_WAITERS, 0))			      \      lll_futex_wake (__futex, 1, 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 with 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 */