process.cc revision 13335:299a16ef8e3c 
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 "systemc/core/event.hh"
33#include "systemc/core/port.hh"
34#include "systemc/core/scheduler.hh"
35#include "systemc/ext/core/messages.hh"
36#include "systemc/ext/core/sc_join.hh"
37#include "systemc/ext/core/sc_main.hh"
38#include "systemc/ext/core/sc_process_handle.hh"
39#include "systemc/ext/utils/sc_report_handler.hh"
40
41namespace sc_gem5
42{
43
44class UnwindExceptionReset : public ::sc_core::sc_unwind_exception
45{
46  public:
47    UnwindExceptionReset() { _isReset = true; }
48};
49
50class UnwindExceptionKill : public ::sc_core::sc_unwind_exception
51{
52  public:
53    UnwindExceptionKill() {}
54};
55
56template <typename T>
57struct BuiltinExceptionWrapper : public ExceptionWrapperBase
58{
59  public:
60    T t;
61    void throw_it() override { throw t; }
62};
63
64BuiltinExceptionWrapper<UnwindExceptionReset> resetException;
65BuiltinExceptionWrapper<UnwindExceptionKill> killException;
66
67
68void
69Process::forEachKid(const std::function<void(Process *)> &work)
70{
71    for (auto &kid: get_child_objects()) {
72        Process *p_kid = dynamic_cast<Process *>(kid);
73        if (p_kid)
74            work(p_kid);
75    }
76}
77
78void
79Process::suspend(bool inc_kids)
80{
81    if (inc_kids)
82        forEachKid([](Process *p) { p->suspend(true); });
83
84    if (!_suspended) {
85        _suspended = true;
86        _suspendedReady = scheduler.suspend(this);
87
88        if (procKind() != ::sc_core::SC_METHOD_PROC_ &&
89                scheduler.current() == this) {
90            // This isn't in the spec, but Accellera says that a thread that
91            // self suspends should be marked ready immediately when it's
92            // resumed.
93            _suspendedReady = true;
94            scheduler.yield();
95        }
96    }
97}
98
99void
100Process::resume(bool inc_kids)
101{
102    if (inc_kids)
103        forEachKid([](Process *p) { p->resume(true); });
104
105    if (_suspended) {
106        _suspended = false;
107        if (_suspendedReady)
108            scheduler.resume(this);
109        _suspendedReady = false;
110    }
111}
112
113void
114Process::disable(bool inc_kids)
115{
116    if (inc_kids)
117        forEachKid([](Process *p) { p->disable(true); });
118
119    if (!::sc_core::sc_allow_process_control_corners &&
120            timeoutEvent.scheduled()) {
121        std::string message("attempt to disable a thread with timeout wait: ");
122        message += name();
123        SC_REPORT_ERROR(sc_core::SC_ID_PROCESS_CONTROL_CORNER_CASE_,
124                message.c_str());
125    }
126
127    _disabled = true;
128}
129
130void
131Process::enable(bool inc_kids)
132{
133
134    if (inc_kids)
135        forEachKid([](Process *p) { p->enable(true); });
136
137    _disabled = false;
138}
139
140void
141Process::kill(bool inc_kids)
142{
143    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
144        SC_REPORT_ERROR(sc_core::SC_ID_KILL_PROCESS_WHILE_UNITIALIZED_,
145                name());
146    }
147
148    // Propogate the kill to our children no matter what happens to us.
149    if (inc_kids)
150        forEachKid([](Process *p) { p->kill(true); });
151
152    // If we're in the middle of unwinding, ignore the kill request.
153    if (_isUnwinding)
154        return;
155
156    // Update our state.
157    terminate();
158    _isUnwinding = true;
159
160    // Make sure this process isn't marked ready
161    popListNode();
162
163    // Inject the kill exception into this process if it's started.
164    if (!_needsStart)
165        injectException(killException);
166}
167
168void
169Process::reset(bool inc_kids)
170{
171    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
172        SC_REPORT_ERROR(sc_core::SC_ID_RESET_PROCESS_WHILE_NOT_RUNNING_,
173                name());
174    }
175
176    // Propogate the reset to our children no matter what happens to us.
177    if (inc_kids)
178        forEachKid([](Process *p) { p->reset(true); });
179
180    // If we're in the middle of unwinding, ignore the reset request.
181    if (_isUnwinding)
182        return;
183
184    // Clear suspended ready since we're about to run regardless.
185    _suspendedReady = false;
186
187    _resetEvent.notify();
188
189    if (_needsStart) {
190        scheduler.runNow(this);
191    } else {
192        _isUnwinding = true;
193        injectException(resetException);
194    }
195}
196
197void
198Process::throw_it(ExceptionWrapperBase &exc, bool inc_kids)
199{
200    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING)
201        SC_REPORT_ERROR(sc_core::SC_ID_THROW_IT_WHILE_NOT_RUNNING_, name());
202
203    if (inc_kids)
204        forEachKid([&exc](Process *p) { p->throw_it(exc, true); });
205
206    if (_needsStart || _terminated ||
207            procKind() == ::sc_core::SC_METHOD_PROC_) {
208        SC_REPORT_WARNING(sc_core::SC_ID_THROW_IT_IGNORED_, name());
209        return;
210    }
211
212    injectException(exc);
213}
214
215void
216Process::injectException(ExceptionWrapperBase &exc)
217{
218    excWrapper = &exc;
219    scheduler.runNow(this);
220};
221
222void
223Process::syncResetOn(bool inc_kids)
224{
225    if (inc_kids)
226        forEachKid([](Process *p) { p->syncResetOn(true); });
227
228    _syncReset = true;
229}
230
231void
232Process::syncResetOff(bool inc_kids)
233{
234    if (inc_kids)
235        forEachKid([](Process *p) { p->syncResetOff(true); });
236
237    _syncReset = false;
238}
239
240void
241Process::signalReset(bool set, bool sync)
242{
243    if (set) {
244        waitCount(0);
245        if (sync) {
246            syncResetCount++;
247        } else {
248            asyncResetCount++;
249            cancelTimeout();
250            clearDynamic();
251            scheduler.runNext(this);
252        }
253    } else {
254        if (sync)
255            syncResetCount--;
256        else
257            asyncResetCount--;
258    }
259}
260
261void
262Process::run()
263{
264    bool reset;
265    do {
266        reset = false;
267        try {
268            func->call();
269        } catch(ScHalt) {
270            std::cout << "Terminating process " << name() << std::endl;
271        } catch(const ::sc_core::sc_unwind_exception &exc) {
272            reset = exc.is_reset();
273            _isUnwinding = false;
274        } catch (...) {
275            throw;
276        }
277    } while (reset);
278    needsStart(true);
279}
280
281void
282Process::addStatic(StaticSensitivity *s)
283{
284    staticSensitivities.push_back(s);
285}
286
287void
288Process::setDynamic(DynamicSensitivity *s)
289{
290    if (dynamicSensitivity) {
291        dynamicSensitivity->clear();
292        delete dynamicSensitivity;
293    }
294    dynamicSensitivity = s;
295}
296
297void
298Process::addReset(Reset *reset)
299{
300    resets.push_back(reset);
301}
302
303void
304Process::cancelTimeout()
305{
306    if (timeoutEvent.scheduled())
307        scheduler.deschedule(&timeoutEvent);
308}
309
310void
311Process::setTimeout(::sc_core::sc_time t)
312{
313    cancelTimeout();
314    scheduler.schedule(&timeoutEvent, t);
315}
316
317void
318Process::timeout()
319{
320    // A process is considered timed_out only if it was also waiting for an
321    // event but got a timeout instead.
322    _timedOut = (dynamicSensitivity != nullptr);
323
324    setDynamic(nullptr);
325    if (disabled())
326        return;
327
328    ready();
329}
330
331void
332Process::satisfySensitivity(Sensitivity *s)
333{
334    if (_waitCount) {
335        _waitCount--;
336        return;
337    }
338
339    // If there's a dynamic sensitivity and this wasn't it, ignore.
340    if ((dynamicSensitivity || timeoutEvent.scheduled()) &&
341            dynamicSensitivity != s) {
342        return;
343    }
344
345    _timedOut = false;
346    // This sensitivity should already be cleared by this point, or the event
347    // which triggered it will take care of it.
348    delete dynamicSensitivity;
349    dynamicSensitivity = nullptr;
350    cancelTimeout();
351    ready();
352}
353
354void
355Process::ready()
356{
357    if (disabled())
358        return;
359    if (suspended())
360        _suspendedReady = true;
361    else if (!scheduled())
362        scheduler.ready(this);
363}
364
365void
366Process::lastReport(::sc_core::sc_report *report)
367{
368    if (report) {
369        _lastReport = std::unique_ptr<::sc_core::sc_report>(
370                new ::sc_core::sc_report(*report));
371    } else {
372        _lastReport = nullptr;
373    }
374}
375
376::sc_core::sc_report *Process::lastReport() const { return _lastReport.get(); }
377
378Process::Process(const char *name, ProcessFuncWrapper *func, bool internal) :
379    ::sc_core::sc_process_b(name), excWrapper(nullptr),
380    timeoutEvent([this]() { this->timeout(); }),
381    func(func), _internal(internal), _timedOut(false), _dontInitialize(false),
382    _needsStart(true), _isUnwinding(false), _terminated(false),
383    _scheduled(false), _suspended(false), _disabled(false),
384    _syncReset(false), syncResetCount(0), asyncResetCount(0), _waitCount(0),
385    refCount(0), stackSize(::Fiber::DefaultStackSize),
386    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