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(BSD) 23 # include <sys/sysctl.h> 24 # endif // defined(BSD) 25 #endif // defined(__unix__) || (defined(__APPLE__) && defined(__MACH__)) 26 27 #if !defined(_WIN32) 28 # include <unistd.h> 29 #endif // !_WIN32 30 31 #if defined(__NetBSD__) 32 #pragma weak pthread_create // Do not create libpthread dependency 33 #endif 34 #if defined(_WIN32) 35 #include <windows.h> 36 #endif 37 38 _LIBCPP_BEGIN_NAMESPACE_STD 39 40 thread::~thread() 41 { 42 if (__t_ != 0) 43 terminate(); 44 } 45 46 void 47 thread::join() 48 { 49 int ec = EINVAL; 50 if (__t_ != 0) 51 { 52 ec = __libcpp_thread_join(&__t_); 53 if (ec == 0) 54 __t_ = 0; 55 } 56 57 if (ec) 58 __throw_system_error(ec, "thread::join failed"); 59 } 60 61 void 62 thread::detach() 63 { 64 int ec = EINVAL; 65 if (__t_ != 0) 66 { 67 ec = __libcpp_thread_detach(&__t_); 68 if (ec == 0) 69 __t_ = 0; 70 } 71 72 if (ec) 73 __throw_system_error(ec, "thread::detach failed"); 74 } 75 76 unsigned 77 thread::hardware_concurrency() _NOEXCEPT 78 { 79 #if defined(CTL_HW) && defined(HW_NCPU) 80 unsigned n; 81 int mib[2] = {CTL_HW, HW_NCPU}; 82 std::size_t s = sizeof(n); 83 sysctl(mib, 2, &n, &s, 0, 0); 84 return n; 85 #elif defined(_SC_NPROCESSORS_ONLN) 86 long result = sysconf(_SC_NPROCESSORS_ONLN); 87 // sysconf returns -1 if the name is invalid, the option does not exist or 88 // does not have a definite limit. 89 // if sysconf returns some other negative number, we have no idea 90 // what is going on. Default to something safe. 91 if (result < 0) 92 return 0; 93 return static_cast<unsigned>(result); 94 #elif defined(_WIN32) 95 SYSTEM_INFO info; 96 GetSystemInfo(&info); 97 return info.dwNumberOfProcessors; 98 #else // defined(CTL_HW) && defined(HW_NCPU) 99 // TODO: grovel through /proc or check cpuid on x86 and similar 100 // instructions on other architectures. 101 # if defined(_MSC_VER) && ! defined(__clang__) 102 _LIBCPP_WARNING("hardware_concurrency not yet implemented") 103 # else 104 # warning hardware_concurrency not yet implemented 105 # endif 106 return 0; // Means not computable [thread.thread.static] 107 #endif // defined(CTL_HW) && defined(HW_NCPU) 108 } 109 110 namespace this_thread 111 { 112 113 void 114 sleep_for(const chrono::nanoseconds& ns) 115 { 116 using namespace chrono; 117 if (ns > nanoseconds::zero()) 118 { 119 seconds s = duration_cast<seconds>(ns); 120 timespec ts; 121 typedef decltype(ts.tv_sec) ts_sec; 122 _LIBCPP_CONSTEXPR ts_sec ts_sec_max = numeric_limits<ts_sec>::max(); 123 if (s.count() < ts_sec_max) 124 { 125 ts.tv_sec = static_cast<ts_sec>(s.count()); 126 ts.tv_nsec = static_cast<decltype(ts.tv_nsec)>((ns-s).count()); 127 } 128 else 129 { 130 ts.tv_sec = ts_sec_max; 131 ts.tv_nsec = giga::num - 1; 132 } 133 134 while (nanosleep(&ts, &ts) == -1 && errno == EINTR) 135 ; 136 } 137 } 138 139 } // this_thread 140 141 __thread_specific_ptr<__thread_struct>& 142 __thread_local_data() 143 { 144 static __thread_specific_ptr<__thread_struct> __p; 145 return __p; 146 } 147 148 // __thread_struct_imp 149 150 template <class T> 151 class _LIBCPP_HIDDEN __hidden_allocator 152 { 153 public: 154 typedef T value_type; 155 156 T* allocate(size_t __n) 157 {return static_cast<T*>(::operator new(__n * sizeof(T)));} 158 void deallocate(T* __p, size_t) {::operator delete(static_cast<void*>(__p));} 159 160 size_t max_size() const {return size_t(~0) / sizeof(T);} 161 }; 162 163 class _LIBCPP_HIDDEN __thread_struct_imp 164 { 165 typedef vector<__assoc_sub_state*, 166 __hidden_allocator<__assoc_sub_state*> > _AsyncStates; 167 typedef vector<pair<condition_variable*, mutex*>, 168 __hidden_allocator<pair<condition_variable*, mutex*> > > _Notify; 169 170 _AsyncStates async_states_; 171 _Notify notify_; 172 173 __thread_struct_imp(const __thread_struct_imp&); 174 __thread_struct_imp& operator=(const __thread_struct_imp&); 175 public: 176 __thread_struct_imp() {} 177 ~__thread_struct_imp(); 178 179 void notify_all_at_thread_exit(condition_variable* cv, mutex* m); 180 void __make_ready_at_thread_exit(__assoc_sub_state* __s); 181 }; 182 183 __thread_struct_imp::~__thread_struct_imp() 184 { 185 for (_Notify::iterator i = notify_.begin(), e = notify_.end(); 186 i != e; ++i) 187 { 188 i->second->unlock(); 189 i->first->notify_all(); 190 } 191 for (_AsyncStates::iterator i = async_states_.begin(), e = async_states_.end(); 192 i != e; ++i) 193 { 194 (*i)->__make_ready(); 195 (*i)->__release_shared(); 196 } 197 } 198 199 void 200 __thread_struct_imp::notify_all_at_thread_exit(condition_variable* cv, mutex* m) 201 { 202 notify_.push_back(pair<condition_variable*, mutex*>(cv, m)); 203 } 204 205 void 206 __thread_struct_imp::__make_ready_at_thread_exit(__assoc_sub_state* __s) 207 { 208 async_states_.push_back(__s); 209 __s->__add_shared(); 210 } 211 212 // __thread_struct 213 214 __thread_struct::__thread_struct() 215 : __p_(new __thread_struct_imp) 216 { 217 } 218 219 __thread_struct::~__thread_struct() 220 { 221 delete __p_; 222 } 223 224 void 225 __thread_struct::notify_all_at_thread_exit(condition_variable* cv, mutex* m) 226 { 227 __p_->notify_all_at_thread_exit(cv, m); 228 } 229 230 void 231 __thread_struct::__make_ready_at_thread_exit(__assoc_sub_state* __s) 232 { 233 __p_->__make_ready_at_thread_exit(__s); 234 } 235 236 _LIBCPP_END_NAMESPACE_STD 237 238 #endif // !_LIBCPP_HAS_NO_THREADS 239