1/*
2 * Copyright 2018 Google, Inc.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met: redistributions of source code must retain the above copyright
7 * notice, this list of conditions and the following disclaimer;
8 * redistributions in binary form must reproduce the above copyright
9 * notice, this list of conditions and the following disclaimer in the
10 * documentation and/or other materials provided with the distribution;
11 * neither the name of the copyright holders nor the names of its
12 * contributors may be used to endorse or promote products derived from
13 * this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
19 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * Authors: Gabe Black
28 */
29
30#ifndef __SYSTEMC_CORE_SCHED_EVENT_HH__
31#define __SYSTEMC_CORE_SCHED_EVENT_HH__
32
33#include <functional>
34#include <list>
35
36#include "base/types.hh"
37
38namespace sc_gem5
39{
40
41class ScEvent;
42
43typedef std::list<ScEvent *> ScEvents;
44
45class ScEvent
46{
47  private:
48    std::function<void()> work;
49    Tick _when;
50    ScEvents *_events;
51    ScEvents::iterator _it;
52
53    friend class Scheduler;
54
55    void
56    schedule(ScEvents &events, Tick w)
57    {
58        when(w);
59        assert(!scheduled());
60        _events = &events;
61        _events->push_back(this);
62        _it = _events->end();
63        _it--;
64    }
65
66    void
67    deschedule()
68    {
69        assert(scheduled());
70        _events->erase(_it);
71        _events = nullptr;
72    }
73  public:
74    ScEvent(std::function<void()> work) :
75        work(work), _when(MaxTick), _events(nullptr)
76    {}
77
78    ~ScEvent();
79
80    bool scheduled() { return _events != nullptr; }
81    ScEvents *scheduledOn() { return _events; }
82
83    void when(Tick w) { _when = w; }
84    Tick when() { return _when; }
85
86    void run() { deschedule(); work(); }
87};
88
89} // namespace sc_gem5
90
91#endif // __SYSTEMC_CORE_SCHED_EVENT_HH__
92