xref: /netbsd-src/lib/libpthread/pthread_int.h (revision fff57c5525bbe431aee7bdb3983954f0627a42cb)
1 /*	$NetBSD: pthread_int.h,v 1.69 2008/05/25 17:05:28 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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * NOTE: when changing anything in this file, please ensure that
34  * libpthread_dbg still compiles.
35  */
36 
37 #ifndef _LIB_PTHREAD_INT_H
38 #define _LIB_PTHREAD_INT_H
39 
40 /* #define PTHREAD__DEBUG */
41 #define ERRORCHECK
42 
43 #include "pthread_types.h"
44 #include "pthread_queue.h"
45 #include "pthread_md.h"
46 
47 /* Need to use libc-private names for atomic operations. */
48 #include "../../common/lib/libc/atomic/atomic_op_namespace.h"
49 
50 #include <sys/atomic.h>
51 #include <sys/tree.h>
52 
53 #include <lwp.h>
54 #include <signal.h>
55 
56 #ifdef __GNUC__
57 #define	PTHREAD_HIDE	__attribute__ ((visibility("hidden")))
58 #else
59 #define	PTHREAD_HIDE	/* nothing */
60 #endif
61 
62 #define PTHREAD_KEYS_MAX 	256
63 #define	PTHREAD__UNPARK_MAX	32
64 
65 /*
66  * The size of this structure needs to be no larger than struct
67  * __pthread_cleanup_store, defined in pthread.h.
68  */
69 struct pt_clean_t {
70 	PTQ_ENTRY(pt_clean_t)	ptc_next;
71 	void	(*ptc_cleanup)(void *);
72 	void	*ptc_arg;
73 };
74 
75 /* Private data for pthread_attr_t */
76 struct pthread_attr_private {
77 	char ptap_name[PTHREAD_MAX_NAMELEN_NP];
78 	void *ptap_namearg;
79 	void *ptap_stackaddr;
80 	size_t ptap_stacksize;
81 	size_t ptap_guardsize;
82 };
83 
84 struct pthread_lock_ops {
85 	void	(*plo_init)(__cpu_simple_lock_t *);
86 	int	(*plo_try)(__cpu_simple_lock_t *);
87 	void	(*plo_unlock)(__cpu_simple_lock_t *);
88 	void	(*plo_lock)(__cpu_simple_lock_t *);
89 };
90 
91 struct	__pthread_st {
92 	pthread_t	pt_self;	/* Must be first. */
93 	unsigned int	pt_magic;	/* Magic number */
94 	int		pt_state;	/* running, blocked, etc. */
95 	pthread_mutex_t	pt_lock;	/* lock on state */
96 	int		pt_flags;	/* see PT_FLAG_* below */
97 	int		pt_cancel;	/* Deferred cancellation */
98 	int		pt_errno;	/* Thread-specific errno. */
99 	stack_t		pt_stack;	/* Our stack */
100 	void		*pt_exitval;	/* Read by pthread_join() */
101 	char		*pt_name;	/* Thread's name, set by the app. */
102 	int		pt_willpark;	/* About to park */
103 	lwpid_t		pt_unpark;	/* Unpark this when parking */
104 	struct pthread_lock_ops pt_lockops;/* Cached to avoid PIC overhead */
105 	pthread_mutex_t	*pt_droplock;	/* Drop this lock if cancelled */
106 	pthread_cond_t	pt_joiners;	/* Threads waiting to join. */
107 
108 	/* Threads to defer waking, usually until pthread_mutex_unlock(). */
109 	lwpid_t		pt_waiters[PTHREAD__UNPARK_MAX];
110 	size_t		pt_nwaiters;
111 
112 	/* Stack of cancellation cleanup handlers and their arguments */
113 	PTQ_HEAD(, pt_clean_t)	pt_cleanup_stack;
114 
115 	/* LWP ID and entry on the list of all threads. */
116 	lwpid_t		pt_lid;
117 	RB_ENTRY(__pthread_st) pt_alltree;
118 	PTQ_ENTRY(__pthread_st) pt_allq;
119 	PTQ_ENTRY(__pthread_st)	pt_deadq;
120 
121 	/*
122 	 * General synchronization data.  We try to align, as threads
123 	 * on other CPUs will access this data frequently.
124 	 */
125 	int		pt_dummy1 __aligned(128);
126 	struct lwpctl 	*pt_lwpctl;	/* Kernel/user comms area */
127 	volatile int	pt_blocking;	/* Blocking in userspace */
128 	volatile int	pt_rwlocked;	/* Handed rwlock successfully */
129 	volatile int	pt_signalled;	/* Received pthread_cond_signal() */
130 	volatile int	pt_mutexwait;	/* Waiting to acquire mutex */
131 	void * volatile pt_mutexnext;	/* Next thread in chain */
132 	void * volatile	pt_sleepobj;	/* Object slept on */
133 	PTQ_ENTRY(__pthread_st) pt_sleep;
134 	void		(*pt_early)(void *);
135 	int		pt_dummy2 __aligned(128);
136 
137 	/* Thread-specific data.  Large so it sits close to the end. */
138 	int		pt_havespecific;
139 	void		*pt_specific[PTHREAD_KEYS_MAX];
140 
141 	/*
142 	 * Context for thread creation.  At the end as it's cached
143 	 * and then only ever passed to _lwp_create().
144 	 */
145 	ucontext_t	pt_uc;
146 };
147 
148 /* Thread states */
149 #define PT_STATE_RUNNING	1
150 #define PT_STATE_ZOMBIE		5
151 #define PT_STATE_DEAD		6
152 
153 /* Flag values */
154 
155 #define PT_FLAG_DETACHED	0x0001
156 #define PT_FLAG_CS_DISABLED	0x0004	/* Cancellation disabled */
157 #define PT_FLAG_CS_ASYNC	0x0008  /* Cancellation is async */
158 #define PT_FLAG_CS_PENDING	0x0010
159 #define PT_FLAG_SCOPE_SYSTEM	0x0040
160 #define PT_FLAG_EXPLICIT_SCHED	0x0080
161 #define PT_FLAG_SUSPENDED	0x0100	/* In the suspended queue */
162 
163 #define PT_MAGIC	0x11110001
164 #define PT_DEAD		0xDEAD0001
165 
166 #define PT_ATTR_MAGIC	0x22220002
167 #define PT_ATTR_DEAD	0xDEAD0002
168 
169 extern int	pthread__stacksize_lg;
170 extern size_t	pthread__stacksize;
171 extern vaddr_t	pthread__stackmask;
172 extern vaddr_t	pthread__threadmask;
173 extern int	pthread__nspins;
174 extern int	pthread__concurrency;
175 extern int 	pthread__osrev;
176 extern int 	pthread__unpark_max;
177 
178 /* Flag to be used in a ucontext_t's uc_flags indicating that
179  * the saved register state is "user" state only, not full
180  * trap state.
181  */
182 #define _UC_USER_BIT		30
183 #define _UC_USER		(1LU << _UC_USER_BIT)
184 
185 /* Utility functions */
186 void	pthread__unpark_all(pthread_queue_t *, pthread_t, pthread_mutex_t *)
187     PTHREAD_HIDE;
188 void	pthread__unpark(pthread_queue_t *, pthread_t, pthread_mutex_t *)
189     PTHREAD_HIDE;
190 int	pthread__park(pthread_t, pthread_mutex_t *, pthread_queue_t *,
191 		      const struct timespec *, int, const void *)
192 		      PTHREAD_HIDE;
193 pthread_mutex_t *pthread__hashlock(volatile const void *) PTHREAD_HIDE;
194 
195 /* Internal locking primitives */
196 void	pthread__lockprim_init(void) PTHREAD_HIDE;
197 void	pthread_lockinit(pthread_spin_t *) PTHREAD_HIDE;
198 
199 static inline void pthread__spinlock(pthread_t, pthread_spin_t *)
200     __attribute__((__always_inline__));
201 static inline void
202 pthread__spinlock(pthread_t self, pthread_spin_t *lock)
203 {
204 	if (__predict_true((*self->pt_lockops.plo_try)(lock)))
205 		return;
206 	(*self->pt_lockops.plo_lock)(lock);
207 }
208 
209 static inline int pthread__spintrylock(pthread_t, pthread_spin_t *)
210     __attribute__((__always_inline__));
211 static inline int
212 pthread__spintrylock(pthread_t self, pthread_spin_t *lock)
213 {
214 	return (*self->pt_lockops.plo_try)(lock);
215 }
216 
217 static inline void pthread__spinunlock(pthread_t, pthread_spin_t *)
218     __attribute__((__always_inline__));
219 static inline void
220 pthread__spinunlock(pthread_t self, pthread_spin_t *lock)
221 {
222 	(*self->pt_lockops.plo_unlock)(lock);
223 }
224 
225 extern const struct pthread_lock_ops *pthread__lock_ops;
226 
227 int	pthread__simple_locked_p(__cpu_simple_lock_t *) PTHREAD_HIDE;
228 #define	pthread__simple_lock_init(alp)	(*pthread__lock_ops->plo_init)(alp)
229 #define	pthread__simple_lock_try(alp)	(*pthread__lock_ops->plo_try)(alp)
230 #define	pthread__simple_unlock(alp)	(*pthread__lock_ops->plo_unlock)(alp)
231 
232 #ifndef _getcontext_u
233 int	_getcontext_u(ucontext_t *) PTHREAD_HIDE;
234 #endif
235 #ifndef _setcontext_u
236 int	_setcontext_u(const ucontext_t *) PTHREAD_HIDE;
237 #endif
238 #ifndef _swapcontext_u
239 int	_swapcontext_u(ucontext_t *, const ucontext_t *) PTHREAD_HIDE;
240 #endif
241 
242 void	pthread__testcancel(pthread_t) PTHREAD_HIDE;
243 int	pthread__find(pthread_t) PTHREAD_HIDE;
244 
245 #ifndef PTHREAD_MD_INIT
246 #define PTHREAD_MD_INIT
247 #endif
248 
249 #ifndef _INITCONTEXT_U_MD
250 #define _INITCONTEXT_U_MD(ucp)
251 #endif
252 
253 #define _INITCONTEXT_U(ucp) do {					\
254 	(ucp)->uc_flags = _UC_CPU | _UC_STACK;				\
255 	_INITCONTEXT_U_MD(ucp)						\
256 	} while (/*CONSTCOND*/0)
257 
258 /* Stack location of pointer to a particular thread */
259 #define pthread__id(sp) \
260 	((pthread_t) (((vaddr_t)(sp)) & pthread__threadmask))
261 
262 #ifdef PTHREAD__HAVE_THREADREG
263 #define	pthread__self()		pthread__threadreg_get()
264 #else
265 #define pthread__self() 	(pthread__id(pthread__sp()))
266 #endif
267 
268 #define pthread__abort()						\
269 	pthread__assertfunc(__FILE__, __LINE__, __func__, "unreachable")
270 
271 #define pthread__assert(e) do {						\
272 	if (__predict_false(!(e)))					\
273        	       pthread__assertfunc(__FILE__, __LINE__, __func__, #e);	\
274         } while (/*CONSTCOND*/0)
275 
276 #define pthread__error(err, msg, e) do {				\
277 	if (__predict_false(!(e))) {					\
278        	       pthread__errorfunc(__FILE__, __LINE__, __func__, msg);	\
279 	       return (err);						\
280 	} 								\
281         } while (/*CONSTCOND*/0)
282 
283 void	pthread__destroy_tsd(pthread_t) PTHREAD_HIDE;
284 void	pthread__assertfunc(const char *, int, const char *, const char *)
285 			    PTHREAD_HIDE;
286 void	pthread__errorfunc(const char *, int, const char *, const char *)
287 			   PTHREAD_HIDE;
288 char	*pthread__getenv(const char *) PTHREAD_HIDE;
289 void	pthread__cancelled(void) PTHREAD_HIDE;
290 void	pthread__mutex_deferwake(pthread_t, pthread_mutex_t *) PTHREAD_HIDE;
291 
292 #ifndef pthread__smt_pause
293 #define	pthread__smt_pause()	/* nothing */
294 #endif
295 
296 /*
297  * Bits in the owner field of the lock that indicate lock state.  If the
298  * WRITE_LOCKED bit is clear, then the owner field is actually a count of
299  * the number of readers.
300  */
301 #define	RW_HAS_WAITERS		0x01	/* lock has waiters */
302 #define	RW_WRITE_WANTED		0x02	/* >= 1 waiter is a writer */
303 #define	RW_WRITE_LOCKED		0x04	/* lock is currently write locked */
304 #define	RW_UNUSED		0x08	/* currently unused */
305 
306 #define	RW_FLAGMASK		0x0f
307 
308 #define	RW_READ_COUNT_SHIFT	4
309 #define	RW_READ_INCR		(1 << RW_READ_COUNT_SHIFT)
310 #define	RW_THREAD		((uintptr_t)-RW_READ_INCR)
311 #define	RW_OWNER(rw)		((rw)->rw_owner & RW_THREAD)
312 #define	RW_COUNT(rw)		((rw)->rw_owner & RW_THREAD)
313 #define	RW_FLAGS(rw)		((rw)->rw_owner & ~RW_THREAD)
314 
315 #endif /* _LIB_PTHREAD_INT_H */
316