process.cc revision 12996:17ec70f9841e 
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#include "systemc/core/process.hh"
31
32#include "base/logging.hh"
33#include "systemc/core/event.hh"
34#include "systemc/core/scheduler.hh"
35
36namespace sc_gem5
37{
38
39SensitivityTimeout::SensitivityTimeout(Process *p, ::sc_core::sc_time t) :
40    Sensitivity(p), timeoutEvent(this), time(t)
41{
42    Tick when = scheduler.getCurTick() + time.value();
43    scheduler.schedule(&timeoutEvent, when);
44}
45
46SensitivityTimeout::~SensitivityTimeout()
47{
48    if (timeoutEvent.scheduled())
49        scheduler.deschedule(&timeoutEvent);
50}
51
52void
53SensitivityTimeout::timeout()
54{
55    scheduler.eventHappened();
56    notify();
57}
58
59SensitivityEvent::SensitivityEvent(
60        Process *p, const ::sc_core::sc_event *e) : Sensitivity(p), event(e)
61{
62    Event::getFromScEvent(event)->addSensitivity(this);
63}
64
65SensitivityEvent::~SensitivityEvent()
66{
67    Event::getFromScEvent(event)->delSensitivity(this);
68}
69
70SensitivityEventAndList::SensitivityEventAndList(
71        Process *p, const ::sc_core::sc_event_and_list *list) :
72    Sensitivity(p), list(list), count(0)
73{
74    for (auto e: list->events)
75        Event::getFromScEvent(e)->addSensitivity(this);
76}
77
78SensitivityEventAndList::~SensitivityEventAndList()
79{
80    for (auto e: list->events)
81        Event::getFromScEvent(e)->delSensitivity(this);
82}
83
84void
85SensitivityEventAndList::notifyWork(Event *e)
86{
87    e->delSensitivity(this);
88    count++;
89    if (count == list->events.size())
90        process->satisfySensitivity(this);
91}
92
93SensitivityEventOrList::SensitivityEventOrList(
94        Process *p, const ::sc_core::sc_event_or_list *list) :
95    Sensitivity(p), list(list)
96{
97    for (auto e: list->events)
98        Event::getFromScEvent(e)->addSensitivity(this);
99}
100
101SensitivityEventOrList::~SensitivityEventOrList()
102{
103    for (auto e: list->events)
104        Event::getFromScEvent(e)->delSensitivity(this);
105}
106
107
108class UnwindExceptionReset : public ::sc_core::sc_unwind_exception
109{
110  public:
111    UnwindExceptionReset() { _isReset = true; }
112};
113
114class UnwindExceptionKill : public ::sc_core::sc_unwind_exception
115{
116  public:
117    UnwindExceptionKill() {}
118};
119
120template <typename T>
121struct BuiltinExceptionWrapper : public ExceptionWrapperBase
122{
123  public:
124    T t;
125    void throw_it() override { throw t; }
126};
127
128BuiltinExceptionWrapper<UnwindExceptionReset> resetException;
129BuiltinExceptionWrapper<UnwindExceptionKill> killException;
130
131
132void
133Process::forEachKid(const std::function<void(Process *)> &work)
134{
135    for (auto &kid: get_child_objects()) {
136        Process *p_kid = dynamic_cast<Process *>(kid);
137        if (p_kid)
138            work(p_kid);
139    }
140}
141
142void
143Process::suspend(bool inc_kids)
144{
145    if (inc_kids)
146        forEachKid([](Process *p) { p->suspend(true); });
147
148    if (!_suspended) {
149        _suspended = true;
150        _suspendedReady = false;
151    }
152
153    if (procKind() != ::sc_core::SC_METHOD_PROC_ &&
154            scheduler.current() == this) {
155        scheduler.yield();
156    }
157}
158
159void
160Process::resume(bool inc_kids)
161{
162    if (inc_kids)
163        forEachKid([](Process *p) { p->resume(true); });
164
165    if (_suspended) {
166        _suspended = false;
167        if (_suspendedReady)
168            ready();
169        _suspendedReady = false;
170    }
171}
172
173void
174Process::disable(bool inc_kids)
175{
176    if (inc_kids)
177        forEachKid([](Process *p) { p->disable(true); });
178
179    _disabled = true;
180}
181
182void
183Process::enable(bool inc_kids)
184{
185
186    if (inc_kids)
187        forEachKid([](Process *p) { p->enable(true); });
188
189    _disabled = false;
190}
191
192void
193Process::kill(bool inc_kids)
194{
195    // Propogate the kill to our children no matter what happens to us.
196    if (inc_kids)
197        forEachKid([](Process *p) { p->kill(true); });
198
199    // If we're in the middle of unwinding, ignore the kill request.
200    if (_isUnwinding)
201        return;
202
203    // Update our state.
204    _terminated = true;
205    _isUnwinding = true;
206    _suspendedReady = false;
207    _suspended = false;
208    _syncReset = false;
209
210    // Inject the kill exception into this process.
211    injectException(killException);
212
213    _terminatedEvent.notify();
214}
215
216void
217Process::reset(bool inc_kids)
218{
219    // Propogate the reset to our children no matter what happens to us.
220    if (inc_kids)
221        forEachKid([](Process *p) { p->reset(true); });
222
223    // If we're in the middle of unwinding, ignore the reset request.
224    if (_isUnwinding)
225        return;
226
227    // Update our state.
228    _isUnwinding = true;
229
230    // Inject the reset exception into this process.
231    injectException(resetException);
232
233    _resetEvent.notify();
234}
235
236void
237Process::throw_it(ExceptionWrapperBase &exc, bool inc_kids)
238{
239    if (inc_kids)
240        forEachKid([&exc](Process *p) { p->throw_it(exc, true); });
241}
242
243void
244Process::injectException(ExceptionWrapperBase &exc)
245{
246    excWrapper = &exc;
247    scheduler.runNow(this);
248};
249
250void
251Process::syncResetOn(bool inc_kids)
252{
253    if (inc_kids)
254        forEachKid([](Process *p) { p->syncResetOn(true); });
255
256    _syncReset = true;
257}
258
259void
260Process::syncResetOff(bool inc_kids)
261{
262    if (inc_kids)
263        forEachKid([](Process *p) { p->syncResetOff(true); });
264
265    _syncReset = false;
266}
267
268void
269Process::dontInitialize()
270{
271    scheduler.dontInitialize(this);
272}
273
274void
275Process::finalize()
276{
277    for (auto &s: pendingStaticSensitivities) {
278        s->finalize(staticSensitivities);
279        delete s;
280        s = nullptr;
281    }
282    pendingStaticSensitivities.clear();
283};
284
285void
286Process::run()
287{
288    bool reset;
289    do {
290        reset = false;
291        try {
292            func->call();
293        } catch(const ::sc_core::sc_unwind_exception &exc) {
294            reset = exc.is_reset();
295            _isUnwinding = false;
296        }
297    } while (reset);
298    _terminated = true;
299}
300
301void
302Process::addStatic(PendingSensitivity *s)
303{
304    pendingStaticSensitivities.push_back(s);
305}
306
307void
308Process::setDynamic(Sensitivity *s)
309{
310    delete dynamicSensitivity;
311    dynamicSensitivity = s;
312}
313
314void
315Process::satisfySensitivity(Sensitivity *s)
316{
317    // If there's a dynamic sensitivity and this wasn't it, ignore.
318    if (dynamicSensitivity && dynamicSensitivity != s)
319        return;
320
321    setDynamic(nullptr);
322    ready();
323}
324
325void
326Process::ready()
327{
328    if (disabled())
329        return;
330    if (suspended())
331        _suspendedReady = true;
332    else
333        scheduler.ready(this);
334}
335
336Process::Process(const char *name, ProcessFuncWrapper *func,
337        bool _dynamic, bool needs_start) :
338    ::sc_core::sc_object(name), excWrapper(nullptr), func(func),
339    _needsStart(needs_start), _dynamic(_dynamic), _isUnwinding(false),
340    _terminated(false), _suspended(false), _disabled(false),
341    _syncReset(false), refCount(0), stackSize(::Fiber::DefaultStackSize),
342    dynamicSensitivity(nullptr)
343{
344    _newest = this;
345}
346
347Process *Process::_newest;
348
349void
350throw_it_wrapper(Process *p, ExceptionWrapperBase &exc, bool inc_kids)
351{
352    p->throw_it(exc, inc_kids);
353}
354
355} // namespace sc_gem5
356