1/* -*-c++-*- OpenThreads library, Copyright (C) 2016  Robert Osfield
2 *
3 * This library is open source and may be redistributed and/or modified under
4 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
5 * (at your option) any later version.  The full license is in LICENSE file
6 * included with this distribution, and on the openscenegraph.org website.
7 *
8 * This library is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11 * OpenSceneGraph Public License for more details.
12*/
13
14
15//
16// Affinity - C++ Affinity class
17// ~~~~~~~~
18//
19
20#ifndef _OPENTHREADS_AFFINITY_
21#define _OPENTHREADS_AFFINITY_
22
23#include <set>
24#include <OpenThreads/Mutex>
25
26namespace OpenThreads {
27
28/**
29 *  @class Affinity
30 *  @brief  Simple container for specifying which CPU a thread should have affinity with.
31 *  An empty Affinity.activeCPUs/default constructed Affinity signifies that a thread should not have any specific affinity and be able to run on all available CPUs.
32 */
33class Affinity
34{
35public:
36
37    Affinity() {}
38
39    Affinity(unsigned int cpuNumber) { activeCPUs.insert(cpuNumber); }
40
41    Affinity(unsigned int cpuNumber, unsigned int cpuCount) { while(cpuCount>0) { activeCPUs.insert(cpuNumber++); --cpuCount; } }
42
43    Affinity(const Affinity& rhs) : activeCPUs(rhs.activeCPUs) {}
44
45    Affinity& operator = (const Affinity& rhs) { if (&rhs!=this) { activeCPUs = rhs.activeCPUs; } return *this; }
46
47
48    /** add a specified cpu core from the list to have affinity to. */
49    void add(unsigned int cpuNmber) { activeCPUs.insert(cpuNmber); }
50
51    /** remove a specified cpu core from the list to have affinity to. */
52    void remove(unsigned int cpuNmber) { activeCPUs.erase(cpuNmber); }
53
54    /** return true if affinity has been provided for specific CPU cores.*/
55    operator bool () const { return !activeCPUs.empty(); }
56
57    typedef std::set<unsigned int> ActiveCPUs;
58
59    /** Set of CPUs that a thread should have affinity to.*/
60    ActiveCPUs activeCPUs;
61};
62
63}
64
65#endif // !_OPENTHREADS_THREAD_
66