xref: /netbsd-src/lib/libpthread/pthread_int.h (revision 76c7fc5f6b13ed0b1508e6b313e88e59977ed78e)
1 /*	$NetBSD: pthread_int.h,v 1.95 2019/03/05 01:35:52 christos 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 #ifndef _LIB_PTHREAD_INT_H
33 #define _LIB_PTHREAD_INT_H
34 
35 #include <sys/tls.h>
36 
37 /* #define PTHREAD__DEBUG */
38 #define ERRORCHECK
39 
40 #include "pthread_types.h"
41 #include "pthread_queue.h"
42 #include "pthread_md.h"
43 
44 /* Need to use libc-private names for atomic operations. */
45 #include "../../common/lib/libc/atomic/atomic_op_namespace.h"
46 
47 #include <sys/atomic.h>
48 #include <sys/rbtree.h>
49 
50 #include <limits.h>
51 #include <lwp.h>
52 #include <signal.h>
53 #include <stdbool.h>
54 
55 #ifdef __GNUC__
56 #define	PTHREAD_HIDE	__attribute__ ((visibility("hidden")))
57 #else
58 #define	PTHREAD_HIDE	/* nothing */
59 #endif
60 
61 #define	PTHREAD__UNPARK_MAX	32
62 
63 /*
64  * The size of this structure needs to be no larger than struct
65  * __pthread_cleanup_store, defined in pthread.h.
66  */
67 struct pt_clean_t {
68 	PTQ_ENTRY(pt_clean_t)	ptc_next;
69 	void	(*ptc_cleanup)(void *);
70 	void	*ptc_arg;
71 };
72 
73 /* Private data for pthread_attr_t */
74 struct pthread_attr_private {
75 	char ptap_name[PTHREAD_MAX_NAMELEN_NP];
76 	void *ptap_namearg;
77 	void *ptap_stackaddr;
78 	size_t ptap_stacksize;
79 	size_t ptap_guardsize;
80 	struct sched_param ptap_sp;
81 	int ptap_policy;
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 #if defined(__HAVE_TLS_VARIANT_I) || defined(__HAVE_TLS_VARIANT_II)
94 	struct tls_tcb	*pt_tls;	/* Thread Local Storage area */
95 #endif
96 	unsigned int	pt_magic;	/* Magic number */
97 	int		pt_state;	/* running, blocked, etc. */
98 	pthread_mutex_t	pt_lock;	/* lock on state */
99 	int		pt_flags;	/* see PT_FLAG_* below */
100 	int		pt_cancel;	/* Deferred cancellation */
101 	int		pt_errno;	/* Thread-specific errno. */
102 	stack_t		pt_stack;	/* Our stack */
103 	bool		pt_stack_allocated;
104 	size_t		pt_guardsize;
105 	void		*pt_exitval;	/* Read by pthread_join() */
106 	char		*pt_name;	/* Thread's name, set by the app. */
107 	int		pt_willpark;	/* About to park */
108 	lwpid_t		pt_unpark;	/* Unpark this when parking */
109 	struct pthread_lock_ops pt_lockops;/* Cached to avoid PIC overhead */
110 	pthread_mutex_t	*pt_droplock;	/* Drop this lock if cancelled */
111 	pthread_cond_t	pt_joiners;	/* Threads waiting to join. */
112 	void		*(*pt_func)(void *);/* Function to call at start. */
113 	void		*pt_arg;	/* Argument to pass at start. */
114 
115 	/* Threads to defer waking, usually until pthread_mutex_unlock(). */
116 	lwpid_t		pt_waiters[PTHREAD__UNPARK_MAX];
117 	size_t		pt_nwaiters;
118 
119 	/* Stack of cancellation cleanup handlers and their arguments */
120 	PTQ_HEAD(, pt_clean_t)	pt_cleanup_stack;
121 
122 	/* LWP ID and entry on the list of all threads. */
123 	lwpid_t		pt_lid;
124 	rb_node_t	pt_alltree;
125 	PTQ_ENTRY(__pthread_st) pt_allq;
126 	PTQ_ENTRY(__pthread_st)	pt_deadq;
127 
128 	/*
129 	 * General synchronization data.  We try to align, as threads
130 	 * on other CPUs will access this data frequently.
131 	 */
132 	int		pt_dummy1 __aligned(128);
133 	struct lwpctl 	*pt_lwpctl;	/* Kernel/user comms area */
134 	volatile int	pt_blocking;	/* Blocking in userspace */
135 	volatile int	pt_rwlocked;	/* Handed rwlock successfully */
136 	volatile int	pt_signalled;	/* Received pthread_cond_signal() */
137 	volatile int	pt_mutexwait;	/* Waiting to acquire mutex */
138 	void * volatile pt_mutexnext;	/* Next thread in chain */
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 	struct pt_specific {
147 		void *pts_value;
148 		PTQ_ENTRY(pt_specific) pts_next;
149 	} pt_specific[];
150 };
151 
152 /* Thread states */
153 #define PT_STATE_RUNNING	1
154 #define PT_STATE_ZOMBIE		5
155 #define PT_STATE_DEAD		6
156 
157 /* Flag values */
158 
159 #define PT_FLAG_DETACHED	0x0001
160 #define PT_FLAG_CS_DISABLED	0x0004	/* Cancellation disabled */
161 #define PT_FLAG_CS_ASYNC	0x0008  /* Cancellation is async */
162 #define PT_FLAG_CS_PENDING	0x0010
163 #define PT_FLAG_SCOPE_SYSTEM	0x0040
164 #define PT_FLAG_EXPLICIT_SCHED	0x0080
165 #define PT_FLAG_SUSPENDED	0x0100	/* In the suspended queue */
166 
167 #define PT_MAGIC	0x11110001
168 #define PT_DEAD		0xDEAD0001
169 
170 #define PT_ATTR_MAGIC	0x22220002
171 #define PT_ATTR_DEAD	0xDEAD0002
172 
173 extern size_t	pthread__stacksize;
174 extern size_t	pthread__guardsize;
175 extern size_t	pthread__pagesize;
176 extern int	pthread__nspins;
177 extern int	pthread__concurrency;
178 extern int 	pthread__osrev;
179 extern int 	pthread__unpark_max;
180 extern int	pthread_keys_max;
181 
182 extern int	__uselibcstub;
183 
184 /* Flag to be used in a ucontext_t's uc_flags indicating that
185  * the saved register state is "user" state only, not full
186  * trap state.
187  */
188 #define _UC_USER_BIT		30
189 #define _UC_USER		(1LU << _UC_USER_BIT)
190 
191 /* Utility functions */
192 void	pthread__unpark_all(pthread_queue_t *, pthread_t, pthread_mutex_t *)
193     PTHREAD_HIDE;
194 void	pthread__unpark(pthread_queue_t *, pthread_t, pthread_mutex_t *)
195     PTHREAD_HIDE;
196 int	pthread__park(pthread_t, pthread_mutex_t *, pthread_queue_t *,
197 		      const struct timespec *, int, const void *)
198 		      PTHREAD_HIDE;
199 pthread_mutex_t *pthread__hashlock(volatile const void *) 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 void	pthread__testcancel(pthread_t) PTHREAD_HIDE;
239 int	pthread__find(pthread_t) PTHREAD_HIDE;
240 
241 #ifndef PTHREAD_MD_INIT
242 #define PTHREAD_MD_INIT
243 #endif
244 
245 #ifndef _INITCONTEXT_U_MD
246 #define _INITCONTEXT_U_MD(ucp)
247 #endif
248 
249 #define _INITCONTEXT_U(ucp) do {					\
250 	(ucp)->uc_flags = _UC_CPU | _UC_STACK;				\
251 	_INITCONTEXT_U_MD(ucp)						\
252 	} while (/*CONSTCOND*/0)
253 
254 
255 #if !defined(__HAVE_TLS_VARIANT_I) && !defined(__HAVE_TLS_VARIANT_II)
256 #error Either __HAVE_TLS_VARIANT_I or __HAVE_TLS_VARIANT_II must be defined
257 #endif
258 
259 #ifdef _PTHREAD_GETTCB_EXT
260 struct tls_tcb *_PTHREAD_GETTCB_EXT(void);
261 #endif
262 
263 static inline pthread_t __constfunc
264 pthread__self(void)
265 {
266 #if defined(_PTHREAD_GETTCB_EXT)
267 	struct tls_tcb * const tcb = _PTHREAD_GETTCB_EXT();
268 #elif defined(__HAVE___LWP_GETTCB_FAST)
269 	struct tls_tcb * const tcb = __lwp_gettcb_fast();
270 #else
271 	struct tls_tcb * const tcb = __lwp_getprivate_fast();
272 #endif
273 	return (pthread_t)tcb->tcb_pthread;
274 }
275 
276 #define pthread__abort()						\
277 	pthread__assertfunc(__FILE__, __LINE__, __func__, "unreachable")
278 
279 #define pthread__assert(e) do {						\
280 	if (__predict_false(!(e)))					\
281        	       pthread__assertfunc(__FILE__, __LINE__, __func__, #e);	\
282         } while (/*CONSTCOND*/0)
283 
284 #define pthread__error(err, msg, e) do {				\
285 	if (__predict_false(!(e))) {					\
286        	       pthread__errorfunc(__FILE__, __LINE__, __func__, msg);	\
287 	       return (err);						\
288 	} 								\
289         } while (/*CONSTCOND*/0)
290 
291 void 	*pthread_tsd_init(size_t *) PTHREAD_HIDE;
292 void	pthread__destroy_tsd(pthread_t) PTHREAD_HIDE;
293 void	pthread__copy_tsd(pthread_t) PTHREAD_HIDE;
294 
295 __dead void	pthread__assertfunc(const char *, int, const char *, const char *)
296 			    PTHREAD_HIDE;
297 void	pthread__errorfunc(const char *, int, const char *, const char *)
298 			   PTHREAD_HIDE;
299 char	*pthread__getenv(const char *) PTHREAD_HIDE;
300 __dead void	pthread__cancelled(void) PTHREAD_HIDE;
301 void	pthread__mutex_deferwake(pthread_t, pthread_mutex_t *) PTHREAD_HIDE;
302 int	pthread__checkpri(int) PTHREAD_HIDE;
303 int	pthread__add_specific(pthread_t, pthread_key_t, const void *) PTHREAD_HIDE;
304 
305 #ifndef pthread__smt_pause
306 #define	pthread__smt_pause()	/* nothing */
307 #endif
308 #ifndef pthread__smt_wake
309 #define	pthread__smt_wake()	/* nothing */
310 #endif
311 
312 /*
313  * Bits in the owner field of the lock that indicate lock state.  If the
314  * WRITE_LOCKED bit is clear, then the owner field is actually a count of
315  * the number of readers.
316  */
317 #define	RW_HAS_WAITERS		0x01	/* lock has waiters */
318 #define	RW_WRITE_WANTED		0x02	/* >= 1 waiter is a writer */
319 #define	RW_WRITE_LOCKED		0x04	/* lock is currently write locked */
320 #define	RW_UNUSED		0x08	/* currently unused */
321 
322 #define	RW_FLAGMASK		0x0f
323 
324 #define	RW_READ_COUNT_SHIFT	4
325 #define	RW_READ_INCR		(1 << RW_READ_COUNT_SHIFT)
326 #define	RW_THREAD		((uintptr_t)-RW_READ_INCR)
327 #define	RW_OWNER(rw)		((rw)->rw_owner & RW_THREAD)
328 #define	RW_COUNT(rw)		((rw)->rw_owner & RW_THREAD)
329 #define	RW_FLAGS(rw)		((rw)->rw_owner & ~RW_THREAD)
330 
331 #endif /* _LIB_PTHREAD_INT_H */
332