process.cc revision 13317:36c574a4036e 
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/port.hh"
35#include "systemc/core/scheduler.hh"
36#include "systemc/ext/core/messages.hh"
37#include "systemc/ext/core/sc_join.hh"
38#include "systemc/ext/core/sc_main.hh"
39#include "systemc/ext/core/sc_process_handle.hh"
40#include "systemc/ext/utils/sc_report_handler.hh"
41
42namespace sc_gem5
43{
44
45class UnwindExceptionReset : public ::sc_core::sc_unwind_exception
46{
47  public:
48    UnwindExceptionReset() { _isReset = true; }
49};
50
51class UnwindExceptionKill : public ::sc_core::sc_unwind_exception
52{
53  public:
54    UnwindExceptionKill() {}
55};
56
57template <typename T>
58struct BuiltinExceptionWrapper : public ExceptionWrapperBase
59{
60  public:
61    T t;
62    void throw_it() override { throw t; }
63};
64
65BuiltinExceptionWrapper<UnwindExceptionReset> resetException;
66BuiltinExceptionWrapper<UnwindExceptionKill> killException;
67
68
69void
70Process::forEachKid(const std::function<void(Process *)> &work)
71{
72    for (auto &kid: get_child_objects()) {
73        Process *p_kid = dynamic_cast<Process *>(kid);
74        if (p_kid)
75            work(p_kid);
76    }
77}
78
79void
80Process::suspend(bool inc_kids)
81{
82    if (inc_kids)
83        forEachKid([](Process *p) { p->suspend(true); });
84
85    if (!_suspended) {
86        _suspended = true;
87        _suspendedReady = scheduler.suspend(this);
88
89        if (procKind() != ::sc_core::SC_METHOD_PROC_ &&
90                scheduler.current() == this) {
91            // This isn't in the spec, but Accellera says that a thread that
92            // self suspends should be marked ready immediately when it's
93            // resumed.
94            _suspendedReady = true;
95            scheduler.yield();
96        }
97    }
98}
99
100void
101Process::resume(bool inc_kids)
102{
103    if (inc_kids)
104        forEachKid([](Process *p) { p->resume(true); });
105
106    if (_suspended) {
107        _suspended = false;
108        if (_suspendedReady)
109            scheduler.resume(this);
110        _suspendedReady = false;
111    }
112}
113
114void
115Process::disable(bool inc_kids)
116{
117    if (inc_kids)
118        forEachKid([](Process *p) { p->disable(true); });
119
120    if (!::sc_core::sc_allow_process_control_corners &&
121            timeoutEvent.scheduled()) {
122        std::string message("attempt to disable a thread with timeout wait: ");
123        message += name();
124        SC_REPORT_ERROR(sc_core::SC_ID_PROCESS_CONTROL_CORNER_CASE_,
125                message.c_str());
126    }
127
128    _disabled = true;
129}
130
131void
132Process::enable(bool inc_kids)
133{
134
135    if (inc_kids)
136        forEachKid([](Process *p) { p->enable(true); });
137
138    _disabled = false;
139}
140
141void
142Process::kill(bool inc_kids)
143{
144    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
145        SC_REPORT_ERROR(sc_core::SC_ID_KILL_PROCESS_WHILE_UNITIALIZED_,
146                name());
147    }
148
149    // Propogate the kill to our children no matter what happens to us.
150    if (inc_kids)
151        forEachKid([](Process *p) { p->kill(true); });
152
153    // If we're in the middle of unwinding, ignore the kill request.
154    if (_isUnwinding)
155        return;
156
157    // Update our state.
158    terminate();
159    _isUnwinding = true;
160
161    // Make sure this process isn't marked ready
162    popListNode();
163
164    // Inject the kill exception into this process if it's started.
165    if (!_needsStart)
166        injectException(killException);
167}
168
169void
170Process::reset(bool inc_kids)
171{
172    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
173        SC_REPORT_ERROR(sc_core::SC_ID_RESET_PROCESS_WHILE_NOT_RUNNING_,
174                name());
175    }
176
177    // Propogate the reset to our children no matter what happens to us.
178    if (inc_kids)
179        forEachKid([](Process *p) { p->reset(true); });
180
181    // If we're in the middle of unwinding, ignore the reset request.
182    if (_isUnwinding)
183        return;
184
185    // Clear suspended ready since we're about to run regardless.
186    _suspendedReady = false;
187
188    _resetEvent.notify();
189
190    if (_needsStart) {
191        scheduler.runNow(this);
192    } else {
193        _isUnwinding = true;
194        injectException(resetException);
195    }
196}
197
198void
199Process::throw_it(ExceptionWrapperBase &exc, bool inc_kids)
200{
201    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING)
202        SC_REPORT_ERROR(sc_core::SC_ID_THROW_IT_WHILE_NOT_RUNNING_, name());
203
204    if (inc_kids)
205        forEachKid([&exc](Process *p) { p->throw_it(exc, true); });
206
207    if (_needsStart || _terminated ||
208            procKind() == ::sc_core::SC_METHOD_PROC_) {
209        SC_REPORT_WARNING(sc_core::SC_ID_THROW_IT_IGNORED_, name());
210        return;
211    }
212
213    injectException(exc);
214}
215
216void
217Process::injectException(ExceptionWrapperBase &exc)
218{
219    excWrapper = &exc;
220    scheduler.runNow(this);
221};
222
223void
224Process::syncResetOn(bool inc_kids)
225{
226    if (inc_kids)
227        forEachKid([](Process *p) { p->syncResetOn(true); });
228
229    _syncReset = true;
230}
231
232void
233Process::syncResetOff(bool inc_kids)
234{
235    if (inc_kids)
236        forEachKid([](Process *p) { p->syncResetOff(true); });
237
238    _syncReset = false;
239}
240
241void
242Process::signalReset(bool set, bool sync)
243{
244    if (set) {
245        waitCount(0);
246        if (sync) {
247            syncResetCount++;
248        } else {
249            asyncResetCount++;
250            cancelTimeout();
251            clearDynamic();
252            scheduler.runNext(this);
253        }
254    } else {
255        if (sync)
256            syncResetCount--;
257        else
258            asyncResetCount--;
259    }
260}
261
262void
263Process::run()
264{
265    bool reset;
266    do {
267        reset = false;
268        try {
269            func->call();
270        } catch(ScHalt) {
271            std::cout << "Terminating process " << name() << std::endl;
272        } catch(const ::sc_core::sc_unwind_exception &exc) {
273            reset = exc.is_reset();
274            _isUnwinding = false;
275        } catch (...) {
276            throw;
277        }
278    } while (reset);
279    needsStart(true);
280}
281
282void
283Process::addStatic(StaticSensitivity *s)
284{
285    staticSensitivities.push_back(s);
286}
287
288void
289Process::setDynamic(DynamicSensitivity *s)
290{
291    if (dynamicSensitivity) {
292        dynamicSensitivity->clear();
293        delete dynamicSensitivity;
294    }
295    dynamicSensitivity = s;
296}
297
298void
299Process::addReset(Reset *reset)
300{
301    resets.push_back(reset);
302}
303
304void
305Process::cancelTimeout()
306{
307    if (timeoutEvent.scheduled())
308        scheduler.deschedule(&timeoutEvent);
309}
310
311void
312Process::setTimeout(::sc_core::sc_time t)
313{
314    cancelTimeout();
315    scheduler.schedule(&timeoutEvent, t);
316}
317
318void
319Process::timeout()
320{
321    // A process is considered timed_out only if it was also waiting for an
322    // event but got a timeout instead.
323    _timedOut = (dynamicSensitivity != nullptr);
324
325    setDynamic(nullptr);
326    if (disabled())
327        return;
328
329    ready();
330}
331
332void
333Process::satisfySensitivity(Sensitivity *s)
334{
335    if (_waitCount) {
336        _waitCount--;
337        return;
338    }
339
340    // If there's a dynamic sensitivity and this wasn't it, ignore.
341    if ((dynamicSensitivity || timeoutEvent.scheduled()) &&
342            dynamicSensitivity != s) {
343        return;
344    }
345
346    _timedOut = false;
347    // This sensitivity should already be cleared by this point, or the event
348    // which triggered it will take care of it.
349    delete dynamicSensitivity;
350    dynamicSensitivity = nullptr;
351    cancelTimeout();
352    ready();
353}
354
355void
356Process::ready()
357{
358    if (disabled())
359        return;
360    if (suspended())
361        _suspendedReady = true;
362    else
363        scheduler.ready(this);
364}
365
366void
367Process::lastReport(::sc_core::sc_report *report)
368{
369    if (report) {
370        _lastReport = std::unique_ptr<::sc_core::sc_report>(
371                new ::sc_core::sc_report(*report));
372    } else {
373        _lastReport = nullptr;
374    }
375}
376
377::sc_core::sc_report *Process::lastReport() const { return _lastReport.get(); }
378
379Process::Process(const char *name, ProcessFuncWrapper *func, bool internal) :
380    ::sc_core::sc_process_b(name), excWrapper(nullptr),
381    timeoutEvent([this]() { this->timeout(); }),
382    func(func), _internal(internal), _timedOut(false), _dontInitialize(false),
383    _needsStart(true), _isUnwinding(false), _terminated(false),
384    _suspended(false), _disabled(false), _syncReset(false), syncResetCount(0),
385    asyncResetCount(0), _waitCount(0), refCount(0),
386    stackSize(::Fiber::DefaultStackSize), dynamicSensitivity(nullptr)
387{
388    _dynamic =
389            (::sc_core::sc_get_status() >
390             ::sc_core::SC_BEFORE_END_OF_ELABORATION);
391    _newest = this;
392}
393
394void
395Process::terminate()
396{
397    _terminated = true;
398    _suspendedReady = false;
399    _suspended = false;
400    _syncReset = false;
401    clearDynamic();
402    cancelTimeout();
403    for (auto s: staticSensitivities) {
404        s->clear();
405        delete s;
406    }
407    staticSensitivities.clear();
408
409    _terminatedEvent.notify();
410
411    for (auto jw: joinWaiters)
412        jw->signal();
413    joinWaiters.clear();
414}
415
416Process *Process::_newest;
417
418void
419throw_it_wrapper(Process *p, ExceptionWrapperBase &exc, bool inc_kids)
420{
421    p->throw_it(exc, inc_kids);
422}
423
424void
425newReset(const sc_core::sc_port_base *pb, Process *p, bool s, bool v)
426{
427    Port *port = Port::fromPort(pb);
428    port->addReset(new Reset(p, s, v));
429}
430
431void
432newReset(const sc_core::sc_signal_in_if<bool> *sig, Process *p, bool s, bool v)
433{
434    Reset *reset = new Reset(p, s, v);
435    if (!reset->install(sig))
436        delete reset;
437}
438
439} // namespace sc_gem5
440