1 // This file is part of OpenCV project.
2 // It is subject to the license terms in the LICENSE file found in the top-level directory
3 // of this distribution and at http://opencv.org/license.html.
4
5 #ifndef OPENCV_CORE_PARALLEL_FOR_TBB_HPP
6 #define OPENCV_CORE_PARALLEL_FOR_TBB_HPP
7
8 #include "opencv2/core/parallel/parallel_backend.hpp"
9 #include <opencv2/core/utils/logger.hpp>
10
11 #ifndef TBB_SUPPRESS_DEPRECATED_MESSAGES // supress warning
12 #define TBB_SUPPRESS_DEPRECATED_MESSAGES 1
13 #endif
14 #include "tbb/tbb.h"
15 #if !defined(TBB_INTERFACE_VERSION)
16 #error "Unknows/unsupported TBB version"
17 #endif
18
19 #if TBB_INTERFACE_VERSION >= 8000
20 #include "tbb/task_arena.h"
21 #endif
22
23 namespace cv { namespace parallel { namespace tbb {
24
25 using namespace ::tbb;
26
27 #if TBB_INTERFACE_VERSION >= 8000
getArena()28 static tbb::task_arena& getArena()
29 {
30 static tbb::task_arena tbbArena(tbb::task_arena::automatic);
31 return tbbArena;
32 }
33 #else
getScheduler()34 static tbb::task_scheduler_init& getScheduler()
35 {
36 static tbb::task_scheduler_init tbbScheduler(tbb::task_scheduler_init::deferred);
37 return tbbScheduler;
38 }
39 #endif
40
41 /** OpenMP parallel_for API implementation
42 *
43 * @sa setParallelForBackend
44 * @ingroup core_parallel_backend
45 */
46 class ParallelForBackend : public ParallelForAPI
47 {
48 protected:
49 int numThreads;
50 int numThreadsMax;
51 public:
ParallelForBackend()52 ParallelForBackend()
53 {
54 CV_LOG_INFO(NULL, "Initializing TBB parallel backend: TBB_INTERFACE_VERSION=" << TBB_INTERFACE_VERSION);
55 numThreads = 0;
56 #if TBB_INTERFACE_VERSION >= 8000
57 (void)getArena();
58 #else
59 (void)getScheduler();
60 #endif
61 }
62
~ParallelForBackend()63 virtual ~ParallelForBackend() {}
64
65 class CallbackProxy
66 {
67 const FN_parallel_for_body_cb_t& callback;
68 void* const callback_data;
69 const int tasks;
70 public:
CallbackProxy(int tasks_,FN_parallel_for_body_cb_t & callback_,void * callback_data_)71 inline CallbackProxy(int tasks_, FN_parallel_for_body_cb_t& callback_, void* callback_data_)
72 : callback(callback_), callback_data(callback_data_), tasks(tasks_)
73 {
74 // nothing
75 }
76
operator ()(const tbb::blocked_range<int> & range) const77 void operator()(const tbb::blocked_range<int>& range) const
78 {
79 this->callback(range.begin(), range.end(), callback_data);
80 }
81
operator ()() const82 void operator()() const
83 {
84 tbb::parallel_for(tbb::blocked_range<int>(0, tasks), *this);
85 }
86 };
87
parallel_for(int tasks,FN_parallel_for_body_cb_t body_callback,void * callback_data)88 virtual void parallel_for(int tasks, FN_parallel_for_body_cb_t body_callback, void* callback_data) CV_OVERRIDE
89 {
90 CallbackProxy task(tasks, body_callback, callback_data);
91 #if TBB_INTERFACE_VERSION >= 8000
92 getArena().execute(task);
93 #else
94 task();
95 #endif
96 }
97
getThreadNum() const98 virtual int getThreadNum() const CV_OVERRIDE
99 {
100 #if TBB_INTERFACE_VERSION >= 9100
101 return tbb::this_task_arena::current_thread_index();
102 #elif TBB_INTERFACE_VERSION >= 8000
103 return tbb::task_arena::current_thread_index();
104 #else
105 return 0;
106 #endif
107 }
108
getNumThreads() const109 virtual int getNumThreads() const CV_OVERRIDE
110 {
111 #if TBB_INTERFACE_VERSION >= 9100
112 return getArena().max_concurrency();
113 #elif TBB_INTERFACE_VERSION >= 8000
114 return numThreads > 0
115 ? numThreads
116 : tbb::task_scheduler_init::default_num_threads();
117 #else
118 return getScheduler().is_active()
119 ? numThreads
120 : tbb::task_scheduler_init::default_num_threads();
121 #endif
122 }
123
setNumThreads(int nThreads)124 virtual int setNumThreads(int nThreads) CV_OVERRIDE
125 {
126 int oldNumThreads = numThreads;
127 numThreads = nThreads;
128
129 #if TBB_INTERFACE_VERSION >= 8000
130 auto& tbbArena = getArena();
131 if (tbbArena.is_active())
132 tbbArena.terminate();
133 if (numThreads > 0)
134 tbbArena.initialize(numThreads);
135 #else
136 auto& tbbScheduler = getScheduler();
137 if (tbbScheduler.is_active())
138 tbbScheduler.terminate();
139 if (numThreads > 0)
140 tbbScheduler.initialize(numThreads);
141 #endif
142 return oldNumThreads;
143 }
144
getName() const145 const char* getName() const CV_OVERRIDE
146 {
147 return "tbb";
148 }
149 };
150
151 }}} // namespace
152
153 #endif // OPENCV_CORE_PARALLEL_FOR_TBB_HPP
154