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 "thread"
11 #include "exception"
12 #include "vector"
13 #include "future"
14 #include "limits"
15 #include <sys/types.h>
16 #if !_WIN32
17 #if !__sun__ && !__linux__
18 #include <sys/sysctl.h>
19 #else
20 #include <unistd.h>
21 #endif // !__sun__ && !__linux__
22 #endif // !_WIN32
23
24 _LIBCPP_BEGIN_NAMESPACE_STD
25
~thread()26 thread::~thread()
27 {
28 if (__t_ != 0)
29 terminate();
30 }
31
32 void
join()33 thread::join()
34 {
35 int ec = pthread_join(__t_, 0);
36 #ifndef _LIBCPP_NO_EXCEPTIONS
37 if (ec)
38 throw system_error(error_code(ec, system_category()), "thread::join failed");
39 #endif // _LIBCPP_NO_EXCEPTIONS
40 __t_ = 0;
41 }
42
43 void
detach()44 thread::detach()
45 {
46 int ec = EINVAL;
47 if (__t_ != 0)
48 {
49 ec = pthread_detach(__t_);
50 if (ec == 0)
51 __t_ = 0;
52 }
53 #ifndef _LIBCPP_NO_EXCEPTIONS
54 if (ec)
55 throw system_error(error_code(ec, system_category()), "thread::detach failed");
56 #endif // _LIBCPP_NO_EXCEPTIONS
57 }
58
59 unsigned
hardware_concurrency()60 thread::hardware_concurrency() _NOEXCEPT
61 {
62 #if defined(CTL_HW) && defined(HW_NCPU)
63 unsigned n;
64 int mib[2] = {CTL_HW, HW_NCPU};
65 std::size_t s = sizeof(n);
66 sysctl(mib, 2, &n, &s, 0, 0);
67 return n;
68 #elif defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE >= 200112L) && defined(_SC_NPROCESSORS_ONLN)
69 long result = sysconf(_SC_NPROCESSORS_ONLN);
70 // sysconf returns -1 if the name is invalid, the option does not exist or
71 // does not have a definite limit.
72 if (result == -1)
73 return 0;
74 return result;
75 #else // defined(CTL_HW) && defined(HW_NCPU)
76 // TODO: grovel through /proc or check cpuid on x86 and similar
77 // instructions on other architectures.
78 return 0; // Means not computable [thread.thread.static]
79 #endif // defined(CTL_HW) && defined(HW_NCPU)
80 }
81
82 namespace this_thread
83 {
84
85 void
sleep_for(const chrono::nanoseconds & ns)86 sleep_for(const chrono::nanoseconds& ns)
87 {
88 using namespace chrono;
89 if (ns > nanoseconds::zero())
90 {
91 seconds s = duration_cast<seconds>(ns);
92 timespec ts;
93 typedef decltype(ts.tv_sec) ts_sec;
94 _LIBCPP_CONSTEXPR ts_sec ts_sec_max = numeric_limits<ts_sec>::max();
95 if (s.count() < ts_sec_max)
96 {
97 ts.tv_sec = static_cast<ts_sec>(s.count());
98 ts.tv_nsec = static_cast<decltype(ts.tv_nsec)>((ns-s).count());
99 }
100 else
101 {
102 ts.tv_sec = ts_sec_max;
103 ts.tv_nsec = giga::num - 1;
104 }
105 nanosleep(&ts, 0);
106 }
107 }
108
109 } // this_thread
110
111 __thread_specific_ptr<__thread_struct>&
__thread_local_data()112 __thread_local_data()
113 {
114 static __thread_specific_ptr<__thread_struct> __p;
115 return __p;
116 }
117
118 // __thread_struct_imp
119
120 template <class T>
121 class _LIBCPP_HIDDEN __hidden_allocator
122 {
123 public:
124 typedef T value_type;
125
allocate(size_t __n)126 T* allocate(size_t __n)
127 {return static_cast<T*>(::operator new(__n * sizeof(T)));}
deallocate(T * __p,size_t)128 void deallocate(T* __p, size_t) {::operator delete((void*)__p);}
129
max_size() const130 size_t max_size() const {return size_t(~0) / sizeof(T);}
131 };
132
133 class _LIBCPP_HIDDEN __thread_struct_imp
134 {
135 typedef vector<__assoc_sub_state*,
136 __hidden_allocator<__assoc_sub_state*> > _AsyncStates;
137 typedef vector<pair<condition_variable*, mutex*>,
138 __hidden_allocator<pair<condition_variable*, mutex*> > > _Notify;
139
140 _AsyncStates async_states_;
141 _Notify notify_;
142
143 __thread_struct_imp(const __thread_struct_imp&);
144 __thread_struct_imp& operator=(const __thread_struct_imp&);
145 public:
__thread_struct_imp()146 __thread_struct_imp() {}
147 ~__thread_struct_imp();
148
149 void notify_all_at_thread_exit(condition_variable* cv, mutex* m);
150 void __make_ready_at_thread_exit(__assoc_sub_state* __s);
151 };
152
~__thread_struct_imp()153 __thread_struct_imp::~__thread_struct_imp()
154 {
155 for (_Notify::iterator i = notify_.begin(), e = notify_.end();
156 i != e; ++i)
157 {
158 i->second->unlock();
159 i->first->notify_all();
160 }
161 for (_AsyncStates::iterator i = async_states_.begin(), e = async_states_.end();
162 i != e; ++i)
163 {
164 (*i)->__make_ready();
165 (*i)->__release_shared();
166 }
167 }
168
169 void
notify_all_at_thread_exit(condition_variable * cv,mutex * m)170 __thread_struct_imp::notify_all_at_thread_exit(condition_variable* cv, mutex* m)
171 {
172 notify_.push_back(pair<condition_variable*, mutex*>(cv, m));
173 }
174
175 void
__make_ready_at_thread_exit(__assoc_sub_state * __s)176 __thread_struct_imp::__make_ready_at_thread_exit(__assoc_sub_state* __s)
177 {
178 async_states_.push_back(__s);
179 __s->__add_shared();
180 }
181
182 // __thread_struct
183
__thread_struct()184 __thread_struct::__thread_struct()
185 : __p_(new __thread_struct_imp)
186 {
187 }
188
~__thread_struct()189 __thread_struct::~__thread_struct()
190 {
191 delete __p_;
192 }
193
194 void
notify_all_at_thread_exit(condition_variable * cv,mutex * m)195 __thread_struct::notify_all_at_thread_exit(condition_variable* cv, mutex* m)
196 {
197 __p_->notify_all_at_thread_exit(cv, m);
198 }
199
200 void
__make_ready_at_thread_exit(__assoc_sub_state * __s)201 __thread_struct::__make_ready_at_thread_exit(__assoc_sub_state* __s)
202 {
203 __p_->__make_ready_at_thread_exit(__s);
204 }
205
206 _LIBCPP_END_NAMESPACE_STD
207