Compute Library
 21.05
OMPScheduler.h
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1 /*
2  * Copyright (c) 2017-2021 Arm Limited.
3  *
4  * SPDX-License-Identifier: MIT
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24 #ifndef ARM_COMPUTE_OMPSCHEDULER_H
25 #define ARM_COMPUTE_OMPSCHEDULER_H
26 
28 
29 namespace arm_compute
30 {
31 /** Pool of threads to automatically split a kernel's execution among several threads. */
32 class OMPScheduler final : public IScheduler
33 {
34 public:
35  /** Constructor. */
36  OMPScheduler();
37  /** Sets the number of threads the scheduler will use to run the kernels.
38  *
39  * @param[in] num_threads If set to 0, then the number returned by omp_get_max_threads() will be used, otherwise the number of threads specified.
40  */
41  void set_num_threads(unsigned int num_threads) override;
42  /** Returns the number of threads that the OMPScheduler has in its pool.
43  *
44  * @return Number of threads available in OMPScheduler.
45  */
46  unsigned int num_threads() const override;
47  /** Multithread the execution of the passed kernel if possible.
48  *
49  * The kernel will run on a single thread if any of these conditions is true:
50  * - ICPPKernel::is_parallelisable() returns false
51  * - The scheduler has been initialized with only one thread.
52  *
53  * @param[in] kernel Kernel to execute.
54  * @param[in] hints Hints for the scheduler.
55  */
56  void schedule(ICPPKernel *kernel, const Hints &hints) override;
57 
58  /** Multithread the execution of the passed kernel if possible.
59  *
60  * The kernel will run on a single thread if any of these conditions is true:
61  * - ICPPKernel::is_parallelisable() returns false
62  * - The scheduler has been initialized with only one thread.
63  *
64  * @param[in] kernel Kernel to execute.
65  * @param[in] hints Hints for the scheduler.
66  * @param[in] window Window to use for kernel execution.
67  * @param[in] tensors Vector containing the tensors to operate on.
68  */
69  void schedule_op(ICPPKernel *kernel, const Hints &hints, const Window &window, ITensorPack &tensors) override;
70 
71 protected:
72  /** Execute all the passed workloads
73  *
74  * @note there is no guarantee regarding the order in which the workloads will be executed or whether or not they will be executed in parallel.
75  *
76  * @param[in] workloads Array of workloads to run
77  */
78  void run_workloads(std::vector<Workload> &workloads) override;
79 
80 private:
81  unsigned int _num_threads;
82 };
83 } // namespace arm_compute
84 #endif /* ARM_COMPUTE_OMPSCHEDULER_H */
void schedule_op(ICPPKernel *kernel, const Hints &hints, const Window &window, ITensorPack &tensors) override
Multithread the execution of the passed kernel if possible.
Common interface for all kernels implemented in C++.
Definition: ICPPKernel.h:38
Scheduler interface to run kernels.
Definition: IScheduler.h:41
void set_num_threads(unsigned int num_threads) override
Sets the number of threads the scheduler will use to run the kernels.
Copyright (c) 2017-2021 Arm Limited.
void schedule(ICPPKernel *kernel, const Hints &hints) override
Multithread the execution of the passed kernel if possible.
Pool of threads to automatically split a kernel's execution among several threads.
Definition: OMPScheduler.h:32
unsigned int num_threads() const override
Returns the number of threads that the OMPScheduler has in its pool.
Tensor packing service.
Definition: ITensorPack.h:37
Describe a multidimensional execution window.
Definition: Window.h:39