1#define	JEMALLOC_MUTEX_C_
2#include "jemalloc/internal/jemalloc_internal.h"
3
4#if defined(JEMALLOC_LAZY_LOCK) && !defined(_WIN32)
5#include <dlfcn.h>
6#endif
7
8#ifndef _CRT_SPINCOUNT
9#define	_CRT_SPINCOUNT 4000
10#endif
11
12/******************************************************************************/
13/* Data. */
14
15#ifdef JEMALLOC_LAZY_LOCK
16bool isthreaded = false;
17#endif
18#ifdef JEMALLOC_MUTEX_INIT_CB
19static bool		postpone_init = true;
20static malloc_mutex_t	*postponed_mutexes = NULL;
21#endif
22
23#if defined(JEMALLOC_LAZY_LOCK) && !defined(_WIN32)
24static void	pthread_create_once(void);
25#endif
26
27/******************************************************************************/
28/*
29 * We intercept pthread_create() calls in order to toggle isthreaded if the
30 * process goes multi-threaded.
31 */
32
33#if defined(JEMALLOC_LAZY_LOCK) && !defined(_WIN32)
34static int (*pthread_create_fptr)(pthread_t *__restrict, const pthread_attr_t *,
35    void *(*)(void *), void *__restrict);
36
37static void
38pthread_create_once(void)
39{
40	pthread_create_fptr = dlsym(RTLD_NEXT, "pthread_create");
41	if (pthread_create_fptr == NULL) {
42		malloc_write("<jemalloc>: Error in dlsym(RTLD_NEXT, "
43		    "\"pthread_create\")\n");
44		abort();
45	}
46
47	isthreaded = true;
48}
49
50JEMALLOC_EXPORT int
51pthread_create(pthread_t *__restrict thread,
52    const pthread_attr_t *__restrict attr, void *(*start_routine)(void *),
53    void *__restrict arg)
54{
55	static pthread_once_t once_control = PTHREAD_ONCE_INIT;
56
57	pthread_once(&once_control, pthread_create_once);
58
59	return (pthread_create_fptr(thread, attr, start_routine, arg));
60}
61#endif
62
63/******************************************************************************/
64
65#ifdef JEMALLOC_MUTEX_INIT_CB
66JEMALLOC_EXPORT int	_pthread_mutex_init_calloc_cb(pthread_mutex_t *mutex,
67    void *(calloc_cb)(size_t, size_t));
68#endif
69
70bool
71malloc_mutex_init(malloc_mutex_t *mutex, const char *name, witness_rank_t rank)
72{
73#ifdef _WIN32
74#  if _WIN32_WINNT >= 0x0600
75	InitializeSRWLock(&mutex->lock);
76#  else
77	if (!InitializeCriticalSectionAndSpinCount(&mutex->lock,
78	    _CRT_SPINCOUNT))
79		return (true);
80#  endif
81#elif (defined(JEMALLOC_OS_UNFAIR_LOCK))
82	mutex->lock = OS_UNFAIR_LOCK_INIT;
83#elif (defined(JEMALLOC_OSSPIN))
84	mutex->lock = 0;
85#elif (defined(JEMALLOC_MUTEX_INIT_CB))
86	if (postpone_init) {
87		mutex->postponed_next = postponed_mutexes;
88		postponed_mutexes = mutex;
89	} else {
90		if (_pthread_mutex_init_calloc_cb(&mutex->lock,
91		    bootstrap_calloc) != 0)
92			return (true);
93	}
94#else
95	pthread_mutexattr_t attr;
96
97	if (pthread_mutexattr_init(&attr) != 0)
98		return (true);
99	pthread_mutexattr_settype(&attr, MALLOC_MUTEX_TYPE);
100	if (pthread_mutex_init(&mutex->lock, &attr) != 0) {
101		pthread_mutexattr_destroy(&attr);
102		return (true);
103	}
104	pthread_mutexattr_destroy(&attr);
105#endif
106	if (config_debug)
107		witness_init(&mutex->witness, name, rank, NULL, NULL);
108	return (false);
109}
110
111void
112malloc_mutex_prefork(tsdn_t *tsdn, malloc_mutex_t *mutex)
113{
114	malloc_mutex_lock(tsdn, mutex);
115}
116
117void
118malloc_mutex_postfork_parent(tsdn_t *tsdn, malloc_mutex_t *mutex)
119{
120	malloc_mutex_unlock(tsdn, mutex);
121}
122
123void
124malloc_mutex_postfork_child(tsdn_t *tsdn, malloc_mutex_t *mutex)
125{
126#ifdef JEMALLOC_MUTEX_INIT_CB
127	malloc_mutex_unlock(tsdn, mutex);
128#else
129	if (malloc_mutex_init(mutex, mutex->witness.name,
130	    mutex->witness.rank)) {
131		malloc_printf("<jemalloc>: Error re-initializing mutex in "
132		    "child\n");
133		if (opt_abort)
134			abort();
135	}
136#endif
137}
138
139bool
140malloc_mutex_boot(void)
141{
142#ifdef JEMALLOC_MUTEX_INIT_CB
143	postpone_init = false;
144	while (postponed_mutexes != NULL) {
145		if (_pthread_mutex_init_calloc_cb(&postponed_mutexes->lock,
146		    bootstrap_calloc) != 0)
147			return (true);
148		postponed_mutexes = postponed_mutexes->postponed_next;
149	}
150#endif
151	return (false);
152}
153