xref: /oneTBB/src/tbb/rml_thread_monitor.h (revision 3e352b48)
1 /*
2     Copyright (c) 2005-2022 Intel Corporation
3 
4     Licensed under the Apache License, Version 2.0 (the "License");
5     you may not use this file except in compliance with the License.
6     You may obtain a copy of the License at
7 
8         http://www.apache.org/licenses/LICENSE-2.0
9 
10     Unless required by applicable law or agreed to in writing, software
11     distributed under the License is distributed on an "AS IS" BASIS,
12     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13     See the License for the specific language governing permissions and
14     limitations under the License.
15 */
16 
17 // All platform-specific threading support is encapsulated here. */
18 
19 #ifndef __RML_thread_monitor_H
20 #define __RML_thread_monitor_H
21 
22 #if __TBB_USE_WINAPI
23 #include <windows.h>
24 #include <process.h>
25 #include <malloc.h> //_alloca
26 #include "misc.h" // support for processor groups
27 #if __TBB_WIN8UI_SUPPORT && (_WIN32_WINNT < 0x0A00)
28 #include <thread>
29 #endif
30 #elif __TBB_USE_POSIX
31 #include <pthread.h>
32 #include <cstring>
33 #include <cstdlib>
34 #else
35 #error Unsupported platform
36 #endif
37 #include <cstdio>
38 
39 #include "oneapi/tbb/detail/_template_helpers.h"
40 
41 #include "itt_notify.h"
42 #include "semaphore.h"
43 
44 // All platform-specific threading support is in this header.
45 
46 #if (_WIN32||_WIN64)&&!__TBB_ipf
47 // Deal with 64K aliasing.  The formula for "offset" is a Fibonacci hash function,
48 // which has the desirable feature of spreading out the offsets fairly evenly
49 // without knowing the total number of offsets, and furthermore unlikely to
50 // accidentally cancel out other 64K aliasing schemes that Microsoft might implement later.
51 // See Knuth Vol 3. "Theorem S" for details on Fibonacci hashing.
52 // The second statement is really does need "volatile", otherwise the compiler might remove the _alloca.
53 #define AVOID_64K_ALIASING(idx)                       \
54     std::size_t offset = (idx+1) * 40503U % (1U<<16);      \
55     void* volatile sink_for_alloca = _alloca(offset); \
56     __TBB_ASSERT_EX(sink_for_alloca, "_alloca failed");
57 #else
58 // Linux thread allocators avoid 64K aliasing.
59 #define AVOID_64K_ALIASING(idx) tbb::detail::suppress_unused_warning(idx)
60 #endif /* _WIN32||_WIN64 */
61 
62 namespace tbb {
63 namespace detail {
64 namespace r1 {
65 
66 // Forward declaration: throws std::runtime_error with what() returning error_code description prefixed with aux_info
67 void handle_perror(int error_code, const char* aux_info);
68 
69 namespace rml {
70 namespace internal {
71 
72 #if __TBB_USE_ITT_NOTIFY
73 static const ::tbb::detail::r1::tchar *SyncType_RML = _T("%Constant");
74 static const ::tbb::detail::r1::tchar *SyncObj_ThreadMonitor = _T("RML Thr Monitor");
75 #endif /* __TBB_USE_ITT_NOTIFY */
76 
77 //! Monitor with limited two-phase commit form of wait.
78 /** At most one thread should wait on an instance at a time. */
79 class thread_monitor {
80 public:
81     thread_monitor() {
82         ITT_SYNC_CREATE(&my_sema, SyncType_RML, SyncObj_ThreadMonitor);
83     }
84     ~thread_monitor() {}
85 
86     //! Notify waiting thread
87     /** Can be called by any thread. */
88     void notify();
89 
90     //! Wait for notification
91     void wait();
92 
93 #if __TBB_USE_WINAPI
94     typedef HANDLE handle_type;
95 
96     #define __RML_DECL_THREAD_ROUTINE unsigned WINAPI
97     typedef unsigned (WINAPI *thread_routine_type)(void*);
98 
99     //! Launch a thread
100     static handle_type launch( thread_routine_type thread_routine, void* arg, std::size_t stack_size, const size_t* worker_index = nullptr );
101 
102 #elif __TBB_USE_POSIX
103     typedef pthread_t handle_type;
104 
105     #define __RML_DECL_THREAD_ROUTINE void*
106     typedef void*(*thread_routine_type)(void*);
107 
108     //! Launch a thread
109     static handle_type launch( thread_routine_type thread_routine, void* arg, std::size_t stack_size );
110 #endif /* __TBB_USE_POSIX */
111 
112     //! Join thread
113     static void join(handle_type handle);
114 
115     //! Detach thread
116     static void detach_thread(handle_type handle);
117 private:
118     // The protection from double notification of the binary semaphore
119     std::atomic<bool> my_notified{ false };
120     binary_semaphore my_sema;
121 #if __TBB_USE_POSIX
122     static void check( int error_code, const char* routine );
123 #endif
124 };
125 
126 #if __TBB_USE_WINAPI
127 
128 #ifndef STACK_SIZE_PARAM_IS_A_RESERVATION
129 #define STACK_SIZE_PARAM_IS_A_RESERVATION 0x00010000
130 #endif
131 
132 // _beginthreadex API is not available in Windows 8 Store* applications, so use std::thread instead
133 #if __TBB_WIN8UI_SUPPORT && (_WIN32_WINNT < 0x0A00)
134 inline thread_monitor::handle_type thread_monitor::launch( thread_routine_type thread_function, void* arg, std::size_t, const std::size_t*) {
135 //TODO: check that exception thrown from std::thread is not swallowed silently
136     std::thread* thread_tmp=new std::thread(thread_function, arg);
137     return thread_tmp->native_handle();
138 }
139 #else
140 inline thread_monitor::handle_type thread_monitor::launch( thread_routine_type thread_routine, void* arg, std::size_t stack_size, const std::size_t* worker_index ) {
141     unsigned thread_id;
142     int number_of_processor_groups = ( worker_index ) ? NumberOfProcessorGroups() : 0;
143     unsigned create_flags = ( number_of_processor_groups > 1 ) ? CREATE_SUSPENDED : 0;
144     HANDLE h = (HANDLE)_beginthreadex( nullptr, unsigned(stack_size), thread_routine, arg, STACK_SIZE_PARAM_IS_A_RESERVATION | create_flags, &thread_id );
145     if( !h ) {
146         handle_perror(0, "thread_monitor::launch: _beginthreadex failed\n");
147     }
148     if ( number_of_processor_groups > 1 ) {
149         MoveThreadIntoProcessorGroup( h, FindProcessorGroupIndex( static_cast<int>(*worker_index) ) );
150         ResumeThread( h );
151     }
152     return h;
153 }
154 #endif //__TBB_WIN8UI_SUPPORT && (_WIN32_WINNT < 0x0A00)
155 
156 void thread_monitor::join(handle_type handle) {
157 #if TBB_USE_ASSERT
158     DWORD res =
159 #endif
160         WaitForSingleObjectEx(handle, INFINITE, FALSE);
161     __TBB_ASSERT( res==WAIT_OBJECT_0, nullptr);
162 #if TBB_USE_ASSERT
163     BOOL val =
164 #endif
165         CloseHandle(handle);
166     __TBB_ASSERT( val, nullptr);
167 }
168 
169 void thread_monitor::detach_thread(handle_type handle) {
170 #if TBB_USE_ASSERT
171     BOOL val =
172 #endif
173         CloseHandle(handle);
174     __TBB_ASSERT( val, nullptr);
175 }
176 
177 #endif /* __TBB_USE_WINAPI */
178 
179 #if __TBB_USE_POSIX
180 inline void thread_monitor::check( int error_code, const char* routine ) {
181     if( error_code ) {
182         handle_perror(error_code, routine);
183     }
184 }
185 
186 inline thread_monitor::handle_type thread_monitor::launch( void* (*thread_routine)(void*), void* arg, std::size_t stack_size ) {
187     // FIXME - consider more graceful recovery than just exiting if a thread cannot be launched.
188     // Note that there are some tricky situations to deal with, such that the thread is already
189     // grabbed as part of an OpenMP team.
190     pthread_attr_t s;
191     check(pthread_attr_init( &s ), "pthread_attr_init has failed");
192     if( stack_size>0 )
193         check(pthread_attr_setstacksize( &s, stack_size ), "pthread_attr_setstack_size has failed" );
194     pthread_t handle;
195     check( pthread_create( &handle, &s, thread_routine, arg ), "pthread_create has failed" );
196     check( pthread_attr_destroy( &s ), "pthread_attr_destroy has failed" );
197     return handle;
198 }
199 
200 void thread_monitor::join(handle_type handle) {
201     check(pthread_join(handle, nullptr), "pthread_join has failed");
202 }
203 
204 void thread_monitor::detach_thread(handle_type handle) {
205     check(pthread_detach(handle), "pthread_detach has failed");
206 }
207 #endif /* __TBB_USE_POSIX */
208 
209 inline void thread_monitor::notify() {
210     // Check that the semaphore is not notified twice
211     if (!my_notified.exchange(true, std::memory_order_release)) {
212         my_sema.V();
213     }
214 }
215 
216 inline void thread_monitor::wait() {
217     my_sema.P();
218     // memory_order_seq_cst is required here to be ordered with
219     // further load checking shutdown state
220     my_notified.store(false, std::memory_order_seq_cst);
221 }
222 
223 } // namespace internal
224 } // namespace rml
225 } // namespace r1
226 } // namespace detail
227 } // namespace tbb
228 
229 #endif /* __RML_thread_monitor_H */
230