xref: /netbsd-src/lib/libpthread/pthread_int.h (revision 46f5119e40af2e51998f686b2fdcc76b5488f7f3)
1 /*	$NetBSD: pthread_int.h,v 1.78 2011/03/17 00:43:48 matt 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 #include <sys/tls.h>
41 
42 /* #define PTHREAD__DEBUG */
43 #define ERRORCHECK
44 
45 #include "pthread_types.h"
46 #include "pthread_queue.h"
47 #include "pthread_md.h"
48 
49 /* Need to use libc-private names for atomic operations. */
50 #include "../../common/lib/libc/atomic/atomic_op_namespace.h"
51 
52 #include <sys/atomic.h>
53 #include <sys/tree.h>
54 
55 #include <lwp.h>
56 #include <signal.h>
57 
58 #ifdef __GNUC__
59 #define	PTHREAD_HIDE	__attribute__ ((visibility("hidden")))
60 #else
61 #define	PTHREAD_HIDE	/* nothing */
62 #endif
63 
64 #define PTHREAD_KEYS_MAX 	256
65 #define	PTHREAD__UNPARK_MAX	32
66 
67 /*
68  * The size of this structure needs to be no larger than struct
69  * __pthread_cleanup_store, defined in pthread.h.
70  */
71 struct pt_clean_t {
72 	PTQ_ENTRY(pt_clean_t)	ptc_next;
73 	void	(*ptc_cleanup)(void *);
74 	void	*ptc_arg;
75 };
76 
77 /* Private data for pthread_attr_t */
78 struct pthread_attr_private {
79 	char ptap_name[PTHREAD_MAX_NAMELEN_NP];
80 	void *ptap_namearg;
81 	void *ptap_stackaddr;
82 	size_t ptap_stacksize;
83 	size_t ptap_guardsize;
84 	struct sched_param ptap_sp;
85 	int ptap_policy;
86 };
87 
88 struct pthread_lock_ops {
89 	void	(*plo_init)(__cpu_simple_lock_t *);
90 	int	(*plo_try)(__cpu_simple_lock_t *);
91 	void	(*plo_unlock)(__cpu_simple_lock_t *);
92 	void	(*plo_lock)(__cpu_simple_lock_t *);
93 };
94 
95 struct	__pthread_st {
96 	pthread_t	pt_self;	/* Must be first. */
97 #if defined(__HAVE_TLS_VARIANT_I) || defined(__HAVE_TLS_VARIANT_II)
98 	struct tls_tcb	*pt_tls;	/* Thread Local Storage area */
99 #endif
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 	struct pthread_lock_ops pt_lockops;/* Cached to avoid PIC overhead */
112 	pthread_mutex_t	*pt_droplock;	/* Drop this lock if cancelled */
113 	pthread_cond_t	pt_joiners;	/* Threads waiting to join. */
114 	void		*(*pt_func)(void *);/* Function to call at start. */
115 	void		*pt_arg;	/* Argumen to pass at start. */
116 
117 	/* Threads to defer waking, usually until pthread_mutex_unlock(). */
118 	lwpid_t		pt_waiters[PTHREAD__UNPARK_MAX];
119 	size_t		pt_nwaiters;
120 
121 	/* Stack of cancellation cleanup handlers and their arguments */
122 	PTQ_HEAD(, pt_clean_t)	pt_cleanup_stack;
123 
124 	/* LWP ID and entry on the list of all threads. */
125 	lwpid_t		pt_lid;
126 	RB_ENTRY(__pthread_st) pt_alltree;
127 	PTQ_ENTRY(__pthread_st) pt_allq;
128 	PTQ_ENTRY(__pthread_st)	pt_deadq;
129 
130 	/*
131 	 * General synchronization data.  We try to align, as threads
132 	 * on other CPUs will access this data frequently.
133 	 */
134 	int		pt_dummy1 __aligned(128);
135 	struct lwpctl 	*pt_lwpctl;	/* Kernel/user comms area */
136 	volatile int	pt_blocking;	/* Blocking in userspace */
137 	volatile int	pt_rwlocked;	/* Handed rwlock successfully */
138 	volatile int	pt_signalled;	/* Received pthread_cond_signal() */
139 	volatile int	pt_mutexwait;	/* Waiting to acquire mutex */
140 	void * volatile pt_mutexnext;	/* Next thread in chain */
141 	void * volatile	pt_sleepobj;	/* Object slept on */
142 	PTQ_ENTRY(__pthread_st) pt_sleep;
143 	void		(*pt_early)(void *);
144 	int		pt_dummy2 __aligned(128);
145 
146 	/* Thread-specific data.  Large so it sits close to the end. */
147 	int		pt_havespecific;
148 	void		*pt_specific[PTHREAD_KEYS_MAX];
149 
150 	/*
151 	 * Context for thread creation.  At the end as it's cached
152 	 * and then only ever passed to _lwp_create().
153 	 */
154 	ucontext_t	pt_uc;
155 };
156 
157 /* Thread states */
158 #define PT_STATE_RUNNING	1
159 #define PT_STATE_ZOMBIE		5
160 #define PT_STATE_DEAD		6
161 
162 /* Flag values */
163 
164 #define PT_FLAG_DETACHED	0x0001
165 #define PT_FLAG_CS_DISABLED	0x0004	/* Cancellation disabled */
166 #define PT_FLAG_CS_ASYNC	0x0008  /* Cancellation is async */
167 #define PT_FLAG_CS_PENDING	0x0010
168 #define PT_FLAG_SCOPE_SYSTEM	0x0040
169 #define PT_FLAG_EXPLICIT_SCHED	0x0080
170 #define PT_FLAG_SUSPENDED	0x0100	/* In the suspended queue */
171 
172 #define PT_MAGIC	0x11110001
173 #define PT_DEAD		0xDEAD0001
174 
175 #define PT_ATTR_MAGIC	0x22220002
176 #define PT_ATTR_DEAD	0xDEAD0002
177 
178 extern int	pthread__stacksize_lg;
179 extern size_t	pthread__stacksize;
180 extern vaddr_t	pthread__stackmask;
181 extern vaddr_t	pthread__threadmask;
182 extern int	pthread__nspins;
183 extern int	pthread__concurrency;
184 extern int 	pthread__osrev;
185 extern int 	pthread__unpark_max;
186 
187 /* Flag to be used in a ucontext_t's uc_flags indicating that
188  * the saved register state is "user" state only, not full
189  * trap state.
190  */
191 #define _UC_USER_BIT		30
192 #define _UC_USER		(1LU << _UC_USER_BIT)
193 
194 /* Utility functions */
195 void	pthread__unpark_all(pthread_queue_t *, pthread_t, pthread_mutex_t *)
196     PTHREAD_HIDE;
197 void	pthread__unpark(pthread_queue_t *, pthread_t, pthread_mutex_t *)
198     PTHREAD_HIDE;
199 int	pthread__park(pthread_t, pthread_mutex_t *, pthread_queue_t *,
200 		      const struct timespec *, int, const void *)
201 		      PTHREAD_HIDE;
202 pthread_mutex_t *pthread__hashlock(volatile const void *) PTHREAD_HIDE;
203 
204 /* Internal locking primitives */
205 void	pthread__lockprim_init(void) PTHREAD_HIDE;
206 void	pthread_lockinit(pthread_spin_t *) PTHREAD_HIDE;
207 
208 static inline void pthread__spinlock(pthread_t, pthread_spin_t *)
209     __attribute__((__always_inline__));
210 static inline void
211 pthread__spinlock(pthread_t self, pthread_spin_t *lock)
212 {
213 	if (__predict_true((*self->pt_lockops.plo_try)(lock)))
214 		return;
215 	(*self->pt_lockops.plo_lock)(lock);
216 }
217 
218 static inline int pthread__spintrylock(pthread_t, pthread_spin_t *)
219     __attribute__((__always_inline__));
220 static inline int
221 pthread__spintrylock(pthread_t self, pthread_spin_t *lock)
222 {
223 	return (*self->pt_lockops.plo_try)(lock);
224 }
225 
226 static inline void pthread__spinunlock(pthread_t, pthread_spin_t *)
227     __attribute__((__always_inline__));
228 static inline void
229 pthread__spinunlock(pthread_t self, pthread_spin_t *lock)
230 {
231 	(*self->pt_lockops.plo_unlock)(lock);
232 }
233 
234 extern const struct pthread_lock_ops *pthread__lock_ops;
235 
236 int	pthread__simple_locked_p(__cpu_simple_lock_t *) PTHREAD_HIDE;
237 #define	pthread__simple_lock_init(alp)	(*pthread__lock_ops->plo_init)(alp)
238 #define	pthread__simple_lock_try(alp)	(*pthread__lock_ops->plo_try)(alp)
239 #define	pthread__simple_unlock(alp)	(*pthread__lock_ops->plo_unlock)(alp)
240 
241 void	pthread__testcancel(pthread_t) PTHREAD_HIDE;
242 int	pthread__find(pthread_t) PTHREAD_HIDE;
243 
244 #ifndef PTHREAD_MD_INIT
245 #define PTHREAD_MD_INIT
246 #endif
247 
248 #ifndef _INITCONTEXT_U_MD
249 #define _INITCONTEXT_U_MD(ucp)
250 #endif
251 
252 #define _INITCONTEXT_U(ucp) do {					\
253 	(ucp)->uc_flags = _UC_CPU | _UC_STACK;				\
254 	_INITCONTEXT_U_MD(ucp)						\
255 	} while (/*CONSTCOND*/0)
256 
257 
258 #if defined(__HAVE_TLS_VARIANT_I) || defined(__HAVE_TLS_VARIANT_II)
259 static inline pthread_t __constfunc
260 pthread__self(void)
261 {
262 #ifdef __HAVE___LWP_GETTCB_FAST
263 	struct tls_tcb * const tcb = __lwp_gettcb_fast();
264 #else
265 	struct tls_tcb * const tcb = __lwp_getprivate_fast();
266 #endif
267 	return (pthread_t)tcb->tcb_pthread;
268 }
269 #elif 0 && defined(__HAVE___LWP_GETPRIVATE_FAST)
270 static inline pthread_t __constfunc
271 pthread__self(void)
272 {
273 	return (pthread_t)__lwp_getprivate_fast();
274 }
275 #else
276 /* Stack location of pointer to a particular thread */
277 extern vaddr_t	pthread__mainbase;
278 extern vaddr_t	pthread__mainstruct;
279 static inline pthread_t
280 pthread__id(vaddr_t sp) {
281 	vaddr_t va = sp & pthread__threadmask;
282 	return (pthread_t)(va == pthread__mainbase ? pthread__mainstruct : va);
283 }
284 #define pthread__self() 	(pthread__id(pthread__sp()))
285 #endif
286 
287 #define pthread__abort()						\
288 	pthread__assertfunc(__FILE__, __LINE__, __func__, "unreachable")
289 
290 #define pthread__assert(e) do {						\
291 	if (__predict_false(!(e)))					\
292        	       pthread__assertfunc(__FILE__, __LINE__, __func__, #e);	\
293         } while (/*CONSTCOND*/0)
294 
295 #define pthread__error(err, msg, e) do {				\
296 	if (__predict_false(!(e))) {					\
297        	       pthread__errorfunc(__FILE__, __LINE__, __func__, msg);	\
298 	       return (err);						\
299 	} 								\
300         } while (/*CONSTCOND*/0)
301 
302 void	pthread__destroy_tsd(pthread_t) PTHREAD_HIDE;
303 void	pthread__assertfunc(const char *, int, const char *, const char *)
304 			    PTHREAD_HIDE;
305 void	pthread__errorfunc(const char *, int, const char *, const char *)
306 			   PTHREAD_HIDE;
307 char	*pthread__getenv(const char *) PTHREAD_HIDE;
308 void	pthread__cancelled(void) PTHREAD_HIDE;
309 void	pthread__mutex_deferwake(pthread_t, pthread_mutex_t *) PTHREAD_HIDE;
310 int	pthread__checkpri(int) PTHREAD_HIDE;
311 
312 #ifndef pthread__smt_pause
313 #define	pthread__smt_pause()	/* nothing */
314 #endif
315 
316 /*
317  * Bits in the owner field of the lock that indicate lock state.  If the
318  * WRITE_LOCKED bit is clear, then the owner field is actually a count of
319  * the number of readers.
320  */
321 #define	RW_HAS_WAITERS		0x01	/* lock has waiters */
322 #define	RW_WRITE_WANTED		0x02	/* >= 1 waiter is a writer */
323 #define	RW_WRITE_LOCKED		0x04	/* lock is currently write locked */
324 #define	RW_UNUSED		0x08	/* currently unused */
325 
326 #define	RW_FLAGMASK		0x0f
327 
328 #define	RW_READ_COUNT_SHIFT	4
329 #define	RW_READ_INCR		(1 << RW_READ_COUNT_SHIFT)
330 #define	RW_THREAD		((uintptr_t)-RW_READ_INCR)
331 #define	RW_OWNER(rw)		((rw)->rw_owner & RW_THREAD)
332 #define	RW_COUNT(rw)		((rw)->rw_owner & RW_THREAD)
333 #define	RW_FLAGS(rw)		((rw)->rw_owner & ~RW_THREAD)
334 
335 #endif /* _LIB_PTHREAD_INT_H */
336