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 !defined(_WIN32) 17 #if !defined(__sun__) && !defined(__linux__) 18 #include <sys/sysctl.h> 19 #endif // !__sun__ && !__linux__ 20 #include <unistd.h> 21 #endif // !_WIN32 22 23 #if defined(__NetBSD__) 24 #pragma weak pthread_create // Do not create libpthread dependency 25 #endif 26 #if defined(_WIN32) 27 #include <windows.h> 28 #endif 29 30 _LIBCPP_BEGIN_NAMESPACE_STD 31 32 thread::~thread() 33 { 34 if (__t_ != 0) 35 terminate(); 36 } 37 38 void 39 thread::join() 40 { 41 int ec = pthread_join(__t_, 0); 42 #ifndef _LIBCPP_NO_EXCEPTIONS 43 if (ec) 44 throw system_error(error_code(ec, system_category()), "thread::join failed"); 45 #else 46 (void)ec; 47 #endif // _LIBCPP_NO_EXCEPTIONS 48 __t_ = 0; 49 } 50 51 void 52 thread::detach() 53 { 54 int ec = EINVAL; 55 if (__t_ != 0) 56 { 57 ec = pthread_detach(__t_); 58 if (ec == 0) 59 __t_ = 0; 60 } 61 #ifndef _LIBCPP_NO_EXCEPTIONS 62 if (ec) 63 throw system_error(error_code(ec, system_category()), "thread::detach failed"); 64 #endif // _LIBCPP_NO_EXCEPTIONS 65 } 66 67 unsigned 68 thread::hardware_concurrency() _NOEXCEPT 69 { 70 #if defined(CTL_HW) && defined(HW_NCPU) 71 unsigned n; 72 int mib[2] = {CTL_HW, HW_NCPU}; 73 std::size_t s = sizeof(n); 74 sysctl(mib, 2, &n, &s, 0, 0); 75 return n; 76 #elif defined(_SC_NPROCESSORS_ONLN) 77 long result = sysconf(_SC_NPROCESSORS_ONLN); 78 // sysconf returns -1 if the name is invalid, the option does not exist or 79 // does not have a definite limit. 80 // if sysconf returns some other negative number, we have no idea 81 // what is going on. Default to something safe. 82 if (result < 0) 83 return 0; 84 return static_cast<unsigned>(result); 85 #elif defined(_WIN32) 86 SYSTEM_INFO info; 87 GetSystemInfo(&info); 88 return info.dwNumberOfProcessors; 89 #else // defined(CTL_HW) && defined(HW_NCPU) 90 // TODO: grovel through /proc or check cpuid on x86 and similar 91 // instructions on other architectures. 92 #warning hardware_concurrency not yet implemented 93 return 0; // Means not computable [thread.thread.static] 94 #endif // defined(CTL_HW) && defined(HW_NCPU) 95 } 96 97 namespace this_thread 98 { 99 100 void 101 sleep_for(const chrono::nanoseconds& ns) 102 { 103 using namespace chrono; 104 if (ns > nanoseconds::zero()) 105 { 106 seconds s = duration_cast<seconds>(ns); 107 timespec ts; 108 typedef decltype(ts.tv_sec) ts_sec; 109 _LIBCPP_CONSTEXPR ts_sec ts_sec_max = numeric_limits<ts_sec>::max(); 110 if (s.count() < ts_sec_max) 111 { 112 ts.tv_sec = static_cast<ts_sec>(s.count()); 113 ts.tv_nsec = static_cast<decltype(ts.tv_nsec)>((ns-s).count()); 114 } 115 else 116 { 117 ts.tv_sec = ts_sec_max; 118 ts.tv_nsec = giga::num - 1; 119 } 120 nanosleep(&ts, 0); 121 } 122 } 123 124 } // this_thread 125 126 __thread_specific_ptr<__thread_struct>& 127 __thread_local_data() 128 { 129 static __thread_specific_ptr<__thread_struct> __p; 130 return __p; 131 } 132 133 // __thread_struct_imp 134 135 template <class T> 136 class _LIBCPP_HIDDEN __hidden_allocator 137 { 138 public: 139 typedef T value_type; 140 141 T* allocate(size_t __n) 142 {return static_cast<T*>(::operator new(__n * sizeof(T)));} 143 void deallocate(T* __p, size_t) {::operator delete((void*)__p);} 144 145 size_t max_size() const {return size_t(~0) / sizeof(T);} 146 }; 147 148 class _LIBCPP_HIDDEN __thread_struct_imp 149 { 150 typedef vector<__assoc_sub_state*, 151 __hidden_allocator<__assoc_sub_state*> > _AsyncStates; 152 typedef vector<pair<condition_variable*, mutex*>, 153 __hidden_allocator<pair<condition_variable*, mutex*> > > _Notify; 154 155 _AsyncStates async_states_; 156 _Notify notify_; 157 158 __thread_struct_imp(const __thread_struct_imp&); 159 __thread_struct_imp& operator=(const __thread_struct_imp&); 160 public: 161 __thread_struct_imp() {} 162 ~__thread_struct_imp(); 163 164 void notify_all_at_thread_exit(condition_variable* cv, mutex* m); 165 void __make_ready_at_thread_exit(__assoc_sub_state* __s); 166 }; 167 168 __thread_struct_imp::~__thread_struct_imp() 169 { 170 for (_Notify::iterator i = notify_.begin(), e = notify_.end(); 171 i != e; ++i) 172 { 173 i->second->unlock(); 174 i->first->notify_all(); 175 } 176 for (_AsyncStates::iterator i = async_states_.begin(), e = async_states_.end(); 177 i != e; ++i) 178 { 179 (*i)->__make_ready(); 180 (*i)->__release_shared(); 181 } 182 } 183 184 void 185 __thread_struct_imp::notify_all_at_thread_exit(condition_variable* cv, mutex* m) 186 { 187 notify_.push_back(pair<condition_variable*, mutex*>(cv, m)); 188 } 189 190 void 191 __thread_struct_imp::__make_ready_at_thread_exit(__assoc_sub_state* __s) 192 { 193 async_states_.push_back(__s); 194 __s->__add_shared(); 195 } 196 197 // __thread_struct 198 199 __thread_struct::__thread_struct() 200 : __p_(new __thread_struct_imp) 201 { 202 } 203 204 __thread_struct::~__thread_struct() 205 { 206 delete __p_; 207 } 208 209 void 210 __thread_struct::notify_all_at_thread_exit(condition_variable* cv, mutex* m) 211 { 212 __p_->notify_all_at_thread_exit(cv, m); 213 } 214 215 void 216 __thread_struct::__make_ready_at_thread_exit(__assoc_sub_state* __s) 217 { 218 __p_->__make_ready_at_thread_exit(__s); 219 } 220 221 _LIBCPP_END_NAMESPACE_STD 222
