1 //===------------------------- thread.cpp----------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "__config"
11 #ifndef _LIBCPP_HAS_NO_THREADS
12
13 #include "thread"
14 #include "exception"
15 #include "vector"
16 #include "future"
17 #include "limits"
18 #include <sys/types.h>
19
20 #if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
21 # include <sys/param.h>
22 # if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) || defined(__APPLE__)
23 # include <sys/sysctl.h>
24 # endif
25 #endif // defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
26
27 #if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__CloudABI__) || defined(__Fuchsia__)
28 # include <unistd.h>
29 #endif // defined(__unix__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__CloudABI__) || defined(__Fuchsia__)
30
31 #if defined(__NetBSD__)
32 #pragma weak pthread_create // Do not create libpthread dependency
33 #endif
34
35 #if defined(_LIBCPP_WIN32API)
36 #include <windows.h>
37 #endif
38
39 _LIBCPP_BEGIN_NAMESPACE_STD
40
~thread()41 thread::~thread()
42 {
43 if (!__libcpp_thread_isnull(&__t_))
44 terminate();
45 }
46
47 void
join()48 thread::join()
49 {
50 int ec = EINVAL;
51 if (!__libcpp_thread_isnull(&__t_))
52 {
53 ec = __libcpp_thread_join(&__t_);
54 if (ec == 0)
55 __t_ = _LIBCPP_NULL_THREAD;
56 }
57
58 if (ec)
59 __throw_system_error(ec, "thread::join failed");
60 }
61
62 void
detach()63 thread::detach()
64 {
65 int ec = EINVAL;
66 if (!__libcpp_thread_isnull(&__t_))
67 {
68 ec = __libcpp_thread_detach(&__t_);
69 if (ec == 0)
70 __t_ = _LIBCPP_NULL_THREAD;
71 }
72
73 if (ec)
74 __throw_system_error(ec, "thread::detach failed");
75 }
76
77 unsigned
hardware_concurrency()78 thread::hardware_concurrency() _NOEXCEPT
79 {
80 #if defined(CTL_HW) && defined(HW_NCPU)
81 unsigned n;
82 int mib[2] = {CTL_HW, HW_NCPU};
83 std::size_t s = sizeof(n);
84 sysctl(mib, 2, &n, &s, 0, 0);
85 return n;
86 #elif defined(_SC_NPROCESSORS_ONLN)
87 long result = sysconf(_SC_NPROCESSORS_ONLN);
88 // sysconf returns -1 if the name is invalid, the option does not exist or
89 // does not have a definite limit.
90 // if sysconf returns some other negative number, we have no idea
91 // what is going on. Default to something safe.
92 if (result < 0)
93 return 0;
94 return static_cast<unsigned>(result);
95 #elif defined(_LIBCPP_WIN32API)
96 SYSTEM_INFO info;
97 GetSystemInfo(&info);
98 return info.dwNumberOfProcessors;
99 #else // defined(CTL_HW) && defined(HW_NCPU)
100 // TODO: grovel through /proc or check cpuid on x86 and similar
101 // instructions on other architectures.
102 # if defined(_LIBCPP_WARNING)
103 _LIBCPP_WARNING("hardware_concurrency not yet implemented")
104 # else
105 # warning hardware_concurrency not yet implemented
106 # endif
107 return 0; // Means not computable [thread.thread.static]
108 #endif // defined(CTL_HW) && defined(HW_NCPU)
109 }
110
111 namespace this_thread
112 {
113
114 void
sleep_for(const chrono::nanoseconds & ns)115 sleep_for(const chrono::nanoseconds& ns)
116 {
117 if (ns > chrono::nanoseconds::zero())
118 {
119 __libcpp_thread_sleep_for(ns);
120 }
121 }
122
123 } // this_thread
124
125 __thread_specific_ptr<__thread_struct>&
__thread_local_data()126 __thread_local_data()
127 {
128 static __thread_specific_ptr<__thread_struct> __p;
129 return __p;
130 }
131
132 // __thread_struct_imp
133
134 template <class T>
135 class _LIBCPP_HIDDEN __hidden_allocator
136 {
137 public:
138 typedef T value_type;
139
allocate(size_t __n)140 T* allocate(size_t __n)
141 {return static_cast<T*>(::operator new(__n * sizeof(T)));}
deallocate(T * __p,size_t)142 void deallocate(T* __p, size_t) {::operator delete(static_cast<void*>(__p));}
143
max_size() const144 size_t max_size() const {return size_t(~0) / sizeof(T);}
145 };
146
147 class _LIBCPP_HIDDEN __thread_struct_imp
148 {
149 typedef vector<__assoc_sub_state*,
150 __hidden_allocator<__assoc_sub_state*> > _AsyncStates;
151 typedef vector<pair<condition_variable*, mutex*>,
152 __hidden_allocator<pair<condition_variable*, mutex*> > > _Notify;
153
154 _AsyncStates async_states_;
155 _Notify notify_;
156
157 __thread_struct_imp(const __thread_struct_imp&);
158 __thread_struct_imp& operator=(const __thread_struct_imp&);
159 public:
__thread_struct_imp()160 __thread_struct_imp() {}
161 ~__thread_struct_imp();
162
163 void notify_all_at_thread_exit(condition_variable* cv, mutex* m);
164 void __make_ready_at_thread_exit(__assoc_sub_state* __s);
165 };
166
~__thread_struct_imp()167 __thread_struct_imp::~__thread_struct_imp()
168 {
169 for (_Notify::iterator i = notify_.begin(), e = notify_.end();
170 i != e; ++i)
171 {
172 i->second->unlock();
173 i->first->notify_all();
174 }
175 for (_AsyncStates::iterator i = async_states_.begin(), e = async_states_.end();
176 i != e; ++i)
177 {
178 (*i)->__make_ready();
179 (*i)->__release_shared();
180 }
181 }
182
183 void
notify_all_at_thread_exit(condition_variable * cv,mutex * m)184 __thread_struct_imp::notify_all_at_thread_exit(condition_variable* cv, mutex* m)
185 {
186 notify_.push_back(pair<condition_variable*, mutex*>(cv, m));
187 }
188
189 void
__make_ready_at_thread_exit(__assoc_sub_state * __s)190 __thread_struct_imp::__make_ready_at_thread_exit(__assoc_sub_state* __s)
191 {
192 async_states_.push_back(__s);
193 __s->__add_shared();
194 }
195
196 // __thread_struct
197
__thread_struct()198 __thread_struct::__thread_struct()
199 : __p_(new __thread_struct_imp)
200 {
201 }
202
~__thread_struct()203 __thread_struct::~__thread_struct()
204 {
205 delete __p_;
206 }
207
208 void
notify_all_at_thread_exit(condition_variable * cv,mutex * m)209 __thread_struct::notify_all_at_thread_exit(condition_variable* cv, mutex* m)
210 {
211 __p_->notify_all_at_thread_exit(cv, m);
212 }
213
214 void
__make_ready_at_thread_exit(__assoc_sub_state * __s)215 __thread_struct::__make_ready_at_thread_exit(__assoc_sub_state* __s)
216 {
217 __p_->__make_ready_at_thread_exit(__s);
218 }
219
220 _LIBCPP_END_NAMESPACE_STD
221
222 #endif // !_LIBCPP_HAS_NO_THREADS
223