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pthread_int.h revision 1.66
      1 /*	$NetBSD: pthread_int.h,v 1.66 2008/02/10 18:50:54 ad Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2001, 2002, 2003, 2006, 2007, 2008 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Nathan J. Williams and Andrew Doran.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *        This product includes software developed by the NetBSD
     21  *        Foundation, Inc. and its contributors.
     22  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  *    contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  * POSSIBILITY OF SUCH DAMAGE.
     37  */
     38 
     39 /*
     40  * NOTE: when changing anything in this file, please ensure that
     41  * libpthread_dbg still compiles.
     42  */
     43 
     44 #ifndef _LIB_PTHREAD_INT_H
     45 #define _LIB_PTHREAD_INT_H
     46 
     47 /* #define PTHREAD__DEBUG */
     48 #define ERRORCHECK
     49 
     50 #include "pthread_types.h"
     51 #include "pthread_queue.h"
     52 #include "pthread_md.h"
     53 
     54 /* Need to use libc-private names for atomic operations. */
     55 #include "../../common/lib/libc/atomic/atomic_op_namespace.h"
     56 
     57 #include <sys/atomic.h>
     58 #include <sys/tree.h>
     59 
     60 #include <lwp.h>
     61 #include <signal.h>
     62 
     63 #ifdef __GNUC__
     64 #define	PTHREAD_HIDE	__attribute__ ((visibility("hidden")))
     65 #else
     66 #define	PTHREAD_HIDE	/* nothing */
     67 #endif
     68 
     69 #define PTHREAD_KEYS_MAX 	256
     70 #define	PTHREAD__UNPARK_MAX	32
     71 
     72 /*
     73  * The size of this structure needs to be no larger than struct
     74  * __pthread_cleanup_store, defined in pthread.h.
     75  */
     76 struct pt_clean_t {
     77 	PTQ_ENTRY(pt_clean_t)	ptc_next;
     78 	void	(*ptc_cleanup)(void *);
     79 	void	*ptc_arg;
     80 };
     81 
     82 /* Private data for pthread_attr_t */
     83 struct pthread_attr_private {
     84 	char ptap_name[PTHREAD_MAX_NAMELEN_NP];
     85 	void *ptap_namearg;
     86 	void *ptap_stackaddr;
     87 	size_t ptap_stacksize;
     88 	size_t ptap_guardsize;
     89 };
     90 
     91 struct pthread_lock_ops {
     92 	void	(*plo_init)(__cpu_simple_lock_t *);
     93 	int	(*plo_try)(__cpu_simple_lock_t *);
     94 	void	(*plo_unlock)(__cpu_simple_lock_t *);
     95 	void	(*plo_lock)(__cpu_simple_lock_t *);
     96 };
     97 
     98 struct	__pthread_st {
     99 	pthread_t	pt_self;	/* Must be first. */
    100 	unsigned int	pt_magic;	/* Magic number */
    101 	int		pt_state;	/* running, blocked, etc. */
    102 	pthread_mutex_t	pt_lock;	/* lock on state */
    103 	int		pt_flags;	/* see PT_FLAG_* below */
    104 	int		pt_cancel;	/* Deferred cancellation */
    105 	int		pt_errno;	/* Thread-specific errno. */
    106 	stack_t		pt_stack;	/* Our stack */
    107 	void		*pt_exitval;	/* Read by pthread_join() */
    108 	char		*pt_name;	/* Thread's name, set by the app. */
    109 	int		pt_willpark;	/* About to park */
    110 	lwpid_t		pt_unpark;	/* Unpark this when parking */
    111 	void		*pt_unparkhint;	/* Hint for the above */
    112 	struct pthread_lock_ops pt_lockops;/* Cached to avoid PIC overhead */
    113 	pthread_mutex_t	*pt_droplock;	/* Drop this lock if cancelled */
    114 	pthread_cond_t	pt_joiners;	/* Threads waiting to join. */
    115 
    116 	/* Threads to defer waking, usually until pthread_mutex_unlock(). */
    117 	lwpid_t		pt_waiters[PTHREAD__UNPARK_MAX];
    118 	size_t		pt_nwaiters;
    119 
    120 	/* Stack of cancellation cleanup handlers and their arguments */
    121 	PTQ_HEAD(, pt_clean_t)	pt_cleanup_stack;
    122 
    123 	/* LWP ID and entry on the list of all threads. */
    124 	lwpid_t		pt_lid;
    125 	RB_ENTRY(__pthread_st) pt_alltree;
    126 	PTQ_ENTRY(__pthread_st) pt_allq;
    127 	PTQ_ENTRY(__pthread_st)	pt_deadq;
    128 
    129 	/*
    130 	 * General synchronization data.  We try to align, as threads
    131 	 * on other CPUs will access this data frequently.
    132 	 */
    133 	int		pt_dummy1 __aligned(128);
    134 	struct lwpctl 	*pt_lwpctl;	/* Kernel/user comms area */
    135 	volatile int	pt_blocking;	/* Blocking in userspace */
    136 	volatile int	pt_rwlocked;	/* Handed rwlock successfully */
    137 	volatile int	pt_sleeponq;	/* On a sleep queue */
    138 	volatile int	pt_signalled;	/* Received pthread_cond_signal() */
    139 	void * volatile	pt_sleepobj;	/* Object slept on */
    140 	PTQ_ENTRY(__pthread_st) pt_sleep;
    141 	void		(*pt_early)(void *);
    142 	int		pt_dummy2 __aligned(128);
    143 
    144 	/* Thread-specific data.  Large so it sits close to the end. */
    145 	int		pt_havespecific;
    146 	void		*pt_specific[PTHREAD_KEYS_MAX];
    147 
    148 	/*
    149 	 * Context for thread creation.  At the end as it's cached
    150 	 * and then only ever passed to _lwp_create().
    151 	 */
    152 	ucontext_t	pt_uc;
    153 };
    154 
    155 /* Thread states */
    156 #define PT_STATE_RUNNING	1
    157 #define PT_STATE_ZOMBIE		5
    158 #define PT_STATE_DEAD		6
    159 
    160 /* Flag values */
    161 
    162 #define PT_FLAG_DETACHED	0x0001
    163 #define PT_FLAG_CS_DISABLED	0x0004	/* Cancellation disabled */
    164 #define PT_FLAG_CS_ASYNC	0x0008  /* Cancellation is async */
    165 #define PT_FLAG_CS_PENDING	0x0010
    166 #define PT_FLAG_SCOPE_SYSTEM	0x0040
    167 #define PT_FLAG_EXPLICIT_SCHED	0x0080
    168 #define PT_FLAG_SUSPENDED	0x0100	/* In the suspended queue */
    169 
    170 #define PT_MAGIC	0x11110001
    171 #define PT_DEAD		0xDEAD0001
    172 
    173 #define PT_ATTR_MAGIC	0x22220002
    174 #define PT_ATTR_DEAD	0xDEAD0002
    175 
    176 extern int	pthread__stacksize_lg;
    177 extern size_t	pthread__stacksize;
    178 extern vaddr_t	pthread__stackmask;
    179 extern vaddr_t	pthread__threadmask;
    180 extern int	pthread__nspins;
    181 extern int	pthread__concurrency;
    182 extern int 	pthread__osrev;
    183 extern int 	pthread__unpark_max;
    184 
    185 /* Flag to be used in a ucontext_t's uc_flags indicating that
    186  * the saved register state is "user" state only, not full
    187  * trap state.
    188  */
    189 #define _UC_USER_BIT		30
    190 #define _UC_USER		(1LU << _UC_USER_BIT)
    191 
    192 /* Utility functions */
    193 void	pthread__unpark_all(pthread_t, pthread_spin_t *, pthread_queue_t *)
    194 			    PTHREAD_HIDE;
    195 void	pthread__unpark(pthread_t, pthread_spin_t *, pthread_queue_t *,
    196 			pthread_t) PTHREAD_HIDE;
    197 int	pthread__park(pthread_t, pthread_spin_t *, pthread_queue_t *,
    198 		      const struct timespec *, int, const void *)
    199 		      PTHREAD_HIDE;
    200 
    201 /* Internal locking primitives */
    202 void	pthread__lockprim_init(void) PTHREAD_HIDE;
    203 void	pthread_lockinit(pthread_spin_t *) PTHREAD_HIDE;
    204 
    205 static inline void pthread__spinlock(pthread_t, pthread_spin_t *)
    206     __attribute__((__always_inline__));
    207 static inline void
    208 pthread__spinlock(pthread_t self, pthread_spin_t *lock)
    209 {
    210 	if (__predict_true((*self->pt_lockops.plo_try)(lock)))
    211 		return;
    212 	(*self->pt_lockops.plo_lock)(lock);
    213 }
    214 
    215 static inline int pthread__spintrylock(pthread_t, pthread_spin_t *)
    216     __attribute__((__always_inline__));
    217 static inline int
    218 pthread__spintrylock(pthread_t self, pthread_spin_t *lock)
    219 {
    220 	return (*self->pt_lockops.plo_try)(lock);
    221 }
    222 
    223 static inline void pthread__spinunlock(pthread_t, pthread_spin_t *)
    224     __attribute__((__always_inline__));
    225 static inline void
    226 pthread__spinunlock(pthread_t self, pthread_spin_t *lock)
    227 {
    228 	(*self->pt_lockops.plo_unlock)(lock);
    229 }
    230 
    231 extern const struct pthread_lock_ops *pthread__lock_ops;
    232 
    233 int	pthread__simple_locked_p(__cpu_simple_lock_t *) PTHREAD_HIDE;
    234 #define	pthread__simple_lock_init(alp)	(*pthread__lock_ops->plo_init)(alp)
    235 #define	pthread__simple_lock_try(alp)	(*pthread__lock_ops->plo_try)(alp)
    236 #define	pthread__simple_unlock(alp)	(*pthread__lock_ops->plo_unlock)(alp)
    237 
    238 #ifndef _getcontext_u
    239 int	_getcontext_u(ucontext_t *) PTHREAD_HIDE;
    240 #endif
    241 #ifndef _setcontext_u
    242 int	_setcontext_u(const ucontext_t *) PTHREAD_HIDE;
    243 #endif
    244 #ifndef _swapcontext_u
    245 int	_swapcontext_u(ucontext_t *, const ucontext_t *) PTHREAD_HIDE;
    246 #endif
    247 
    248 void	pthread__testcancel(pthread_t) PTHREAD_HIDE;
    249 int	pthread__find(pthread_t) PTHREAD_HIDE;
    250 
    251 #ifndef PTHREAD_MD_INIT
    252 #define PTHREAD_MD_INIT
    253 #endif
    254 
    255 #ifndef _INITCONTEXT_U_MD
    256 #define _INITCONTEXT_U_MD(ucp)
    257 #endif
    258 
    259 #define _INITCONTEXT_U(ucp) do {					\
    260 	(ucp)->uc_flags = _UC_CPU | _UC_STACK;				\
    261 	_INITCONTEXT_U_MD(ucp)						\
    262 	} while (/*CONSTCOND*/0)
    263 
    264 /* Stack location of pointer to a particular thread */
    265 #define pthread__id(sp) \
    266 	((pthread_t) (((vaddr_t)(sp)) & pthread__threadmask))
    267 
    268 #ifdef PTHREAD__HAVE_THREADREG
    269 #define	pthread__self()		pthread__threadreg_get()
    270 #else
    271 #define pthread__self() 	(pthread__id(pthread__sp()))
    272 #endif
    273 
    274 #define pthread__abort()						\
    275 	pthread__assertfunc(__FILE__, __LINE__, __func__, "unreachable")
    276 
    277 #define pthread__assert(e) do {						\
    278 	if (__predict_false(!(e)))					\
    279        	       pthread__assertfunc(__FILE__, __LINE__, __func__, #e);	\
    280         } while (/*CONSTCOND*/0)
    281 
    282 #define pthread__error(err, msg, e) do {				\
    283 	if (__predict_false(!(e))) {					\
    284        	       pthread__errorfunc(__FILE__, __LINE__, __func__, msg);	\
    285 	       return (err);						\
    286 	} 								\
    287         } while (/*CONSTCOND*/0)
    288 
    289 void	pthread__destroy_tsd(pthread_t) PTHREAD_HIDE;
    290 void	pthread__assertfunc(const char *, int, const char *, const char *)
    291 			    PTHREAD_HIDE;
    292 void	pthread__errorfunc(const char *, int, const char *, const char *)
    293 			   PTHREAD_HIDE;
    294 char	*pthread__getenv(const char *) PTHREAD_HIDE;
    295 void	pthread__cancelled(void) PTHREAD_HIDE;
    296 int	pthread__mutex_deferwake(pthread_t, pthread_mutex_t *) PTHREAD_HIDE;
    297 
    298 #ifndef pthread__smt_pause
    299 #define	pthread__smt_pause()	/* nothing */
    300 #endif
    301 
    302 /*
    303  * Bits in the owner field of the lock that indicate lock state.  If the
    304  * WRITE_LOCKED bit is clear, then the owner field is actually a count of
    305  * the number of readers.
    306  */
    307 #define	RW_HAS_WAITERS		0x01	/* lock has waiters */
    308 #define	RW_WRITE_WANTED		0x02	/* >= 1 waiter is a writer */
    309 #define	RW_WRITE_LOCKED		0x04	/* lock is currently write locked */
    310 #define	RW_UNUSED		0x08	/* currently unused */
    311 
    312 #define	RW_FLAGMASK		0x0f
    313 
    314 #define	RW_READ_COUNT_SHIFT	4
    315 #define	RW_READ_INCR		(1 << RW_READ_COUNT_SHIFT)
    316 #define	RW_THREAD		((uintptr_t)-RW_READ_INCR)
    317 #define	RW_OWNER(rw)		((rw)->rw_owner & RW_THREAD)
    318 #define	RW_COUNT(rw)		((rw)->rw_owner & RW_THREAD)
    319 #define	RW_FLAGS(rw)		((rw)->rw_owner & ~RW_THREAD)
    320 
    321 #define	ptr_owner		ptr_writer
    322 
    323 #endif /* _LIB_PTHREAD_INT_H */
    324