xref: /netbsd-src/lib/libpthread/pthread_int.h (revision 7c3f385475147b6e1c4753f2bee961630e2dfc40)
1 /*	$NetBSD: pthread_int.h,v 1.67 2008/02/14 21:40:51 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 #endif /* _LIB_PTHREAD_INT_H */
322