process.cc revision 13196:4b5ab2c22743 
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#include "systemc/ext/core/sc_join.hh"
36#include "systemc/ext/core/sc_main.hh"
37#include "systemc/ext/core/sc_process_handle.hh"
38#include "systemc/ext/utils/sc_report_handler.hh"
39
40namespace sc_gem5
41{
42
43SensitivityTimeout::SensitivityTimeout(Process *p, ::sc_core::sc_time t) :
44    Sensitivity(p), timeoutEvent([this]() { this->timeout(); })
45{
46    scheduler.schedule(&timeoutEvent, t);
47}
48
49SensitivityTimeout::~SensitivityTimeout()
50{
51    if (timeoutEvent.scheduled())
52        scheduler.deschedule(&timeoutEvent);
53}
54
55void
56SensitivityTimeout::timeout()
57{
58    notify();
59}
60
61SensitivityEvent::SensitivityEvent(
62        Process *p, const ::sc_core::sc_event *e) : Sensitivity(p), event(e)
63{
64    Event::getFromScEvent(event)->addSensitivity(this);
65}
66
67SensitivityEvent::~SensitivityEvent()
68{
69    Event::getFromScEvent(event)->delSensitivity(this);
70}
71
72SensitivityEventAndList::SensitivityEventAndList(
73        Process *p, const ::sc_core::sc_event_and_list *list) :
74    Sensitivity(p), list(list), count(0)
75{
76    for (auto e: list->events)
77        Event::getFromScEvent(e)->addSensitivity(this);
78}
79
80SensitivityEventAndList::~SensitivityEventAndList()
81{
82    for (auto e: list->events)
83        Event::getFromScEvent(e)->delSensitivity(this);
84}
85
86void
87SensitivityEventAndList::notifyWork(Event *e)
88{
89    e->delSensitivity(this);
90    count++;
91    if (count == list->events.size())
92        satisfy();
93}
94
95SensitivityEventOrList::SensitivityEventOrList(
96        Process *p, const ::sc_core::sc_event_or_list *list) :
97    Sensitivity(p), list(list)
98{
99    for (auto e: list->events)
100        Event::getFromScEvent(e)->addSensitivity(this);
101}
102
103SensitivityEventOrList::~SensitivityEventOrList()
104{
105    for (auto e: list->events)
106        Event::getFromScEvent(e)->delSensitivity(this);
107}
108
109void
110SensitivityTimeoutAndEventAndList::notifyWork(Event *e)
111{
112    if (e) {
113        // An event went off which must be part of the sc_event_and_list.
114        SensitivityEventAndList::notifyWork(e);
115    } else {
116        // There's no inciting event, so this must be a timeout.
117        satisfy(true);
118    }
119}
120
121
122class UnwindExceptionReset : public ::sc_core::sc_unwind_exception
123{
124  public:
125    UnwindExceptionReset() { _isReset = true; }
126};
127
128class UnwindExceptionKill : public ::sc_core::sc_unwind_exception
129{
130  public:
131    UnwindExceptionKill() {}
132};
133
134template <typename T>
135struct BuiltinExceptionWrapper : public ExceptionWrapperBase
136{
137  public:
138    T t;
139    void throw_it() override { throw t; }
140};
141
142BuiltinExceptionWrapper<UnwindExceptionReset> resetException;
143BuiltinExceptionWrapper<UnwindExceptionKill> killException;
144
145
146void
147Process::forEachKid(const std::function<void(Process *)> &work)
148{
149    for (auto &kid: get_child_objects()) {
150        Process *p_kid = dynamic_cast<Process *>(kid);
151        if (p_kid)
152            work(p_kid);
153    }
154}
155
156void
157Process::suspend(bool inc_kids)
158{
159    if (inc_kids)
160        forEachKid([](Process *p) { p->suspend(true); });
161
162    if (!_suspended) {
163        _suspended = true;
164        _suspendedReady = scheduler.suspend(this);
165
166        if (procKind() != ::sc_core::SC_METHOD_PROC_ &&
167                scheduler.current() == this) {
168            // This isn't in the spec, but Accellera says that a thread that
169            // self suspends should be marked ready immediately when it's
170            // resumed.
171            _suspendedReady = true;
172            scheduler.yield();
173        }
174    }
175}
176
177void
178Process::resume(bool inc_kids)
179{
180    if (inc_kids)
181        forEachKid([](Process *p) { p->resume(true); });
182
183    if (_suspended) {
184        _suspended = false;
185        if (_suspendedReady)
186            scheduler.resume(this);
187        _suspendedReady = false;
188    }
189}
190
191void
192Process::disable(bool inc_kids)
193{
194    if (inc_kids)
195        forEachKid([](Process *p) { p->disable(true); });
196
197    if (!::sc_core::sc_allow_process_control_corners &&
198            dynamic_cast<SensitivityTimeout *>(dynamicSensitivity)) {
199        std::string message("attempt to disable a thread with timeout wait: ");
200        message += name();
201        SC_REPORT_ERROR("Undefined process control interaction",
202                message.c_str());
203    }
204
205    _disabled = true;
206}
207
208void
209Process::enable(bool inc_kids)
210{
211
212    if (inc_kids)
213        forEachKid([](Process *p) { p->enable(true); });
214
215    _disabled = false;
216}
217
218void
219Process::kill(bool inc_kids)
220{
221    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
222        SC_REPORT_ERROR(
223                "(E572) a process may not be killed before it is initialized",
224                name());
225    }
226
227    // Propogate the kill to our children no matter what happens to us.
228    if (inc_kids)
229        forEachKid([](Process *p) { p->kill(true); });
230
231    // If we're in the middle of unwinding, ignore the kill request.
232    if (_isUnwinding)
233        return;
234
235    // Update our state.
236    terminate();
237    _isUnwinding = true;
238
239    // Make sure this process isn't marked ready
240    popListNode();
241
242    // Inject the kill exception into this process if it's started.
243    if (!_needsStart)
244        injectException(killException);
245}
246
247void
248Process::reset(bool inc_kids)
249{
250    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
251        SC_REPORT_ERROR(
252                "(E573) a process may not be asynchronously reset while"
253                "the simulation is not running", name());
254    }
255
256    // Propogate the reset to our children no matter what happens to us.
257    if (inc_kids)
258        forEachKid([](Process *p) { p->reset(true); });
259
260    // If we're in the middle of unwinding, ignore the reset request.
261    if (_isUnwinding)
262        return;
263
264
265    if (_needsStart) {
266        scheduler.runNow(this);
267    } else {
268        _isUnwinding = true;
269        injectException(resetException);
270    }
271
272    _resetEvent.notify();
273}
274
275void
276Process::throw_it(ExceptionWrapperBase &exc, bool inc_kids)
277{
278    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
279        SC_REPORT_ERROR(
280                "(E574) throw_it not allowed unless simulation is running ",
281                name());
282    }
283
284    if (inc_kids)
285        forEachKid([&exc](Process *p) { p->throw_it(exc, true); });
286
287    // Only inject an exception into threads that have started.
288    if (!_needsStart)
289        injectException(exc);
290}
291
292void
293Process::injectException(ExceptionWrapperBase &exc)
294{
295    excWrapper = &exc;
296    scheduler.runNow(this);
297};
298
299void
300Process::syncResetOn(bool inc_kids)
301{
302    if (inc_kids)
303        forEachKid([](Process *p) { p->syncResetOn(true); });
304
305    _syncReset = true;
306}
307
308void
309Process::syncResetOff(bool inc_kids)
310{
311    if (inc_kids)
312        forEachKid([](Process *p) { p->syncResetOff(true); });
313
314    _syncReset = false;
315}
316
317void
318Process::finalize()
319{
320    for (auto &s: pendingStaticSensitivities) {
321        s->finalize(staticSensitivities);
322        delete s;
323        s = nullptr;
324    }
325    pendingStaticSensitivities.clear();
326};
327
328void
329Process::run()
330{
331    bool reset;
332    do {
333        reset = false;
334        try {
335            func->call();
336        } catch(ScHalt) {
337            std::cout << "Terminating process " << name() << std::endl;
338        } catch(const ::sc_core::sc_unwind_exception &exc) {
339            reset = exc.is_reset();
340            _isUnwinding = false;
341        } catch (...) {
342            throw;
343        }
344    } while (reset);
345    needsStart(true);
346}
347
348void
349Process::addStatic(PendingSensitivity *s)
350{
351    pendingStaticSensitivities.push_back(s);
352}
353
354void
355Process::setDynamic(Sensitivity *s)
356{
357    delete dynamicSensitivity;
358    dynamicSensitivity = s;
359}
360
361void
362Process::satisfySensitivity(Sensitivity *s)
363{
364    // If there's a dynamic sensitivity and this wasn't it, ignore.
365    if (dynamicSensitivity && dynamicSensitivity != s)
366        return;
367
368    setDynamic(nullptr);
369    ready();
370}
371
372void
373Process::ready()
374{
375    if (disabled())
376        return;
377    if (suspended())
378        _suspendedReady = true;
379    else
380        scheduler.ready(this);
381}
382
383void
384Process::lastReport(::sc_core::sc_report *report)
385{
386    if (report) {
387        _lastReport = std::unique_ptr<::sc_core::sc_report>(
388                new ::sc_core::sc_report(*report));
389    } else {
390        _lastReport = nullptr;
391    }
392}
393
394::sc_core::sc_report *Process::lastReport() const { return _lastReport.get(); }
395
396Process::Process(const char *name, ProcessFuncWrapper *func, bool internal) :
397    ::sc_core::sc_process_b(name), excWrapper(nullptr), func(func),
398    _internal(internal), _timedOut(false), _dontInitialize(false),
399    _needsStart(true), _isUnwinding(false), _terminated(false),
400    _suspended(false), _disabled(false), _syncReset(false), refCount(0),
401    stackSize(::Fiber::DefaultStackSize), dynamicSensitivity(nullptr)
402{
403    _dynamic =
404            (::sc_core::sc_get_status() >
405             ::sc_core::SC_BEFORE_END_OF_ELABORATION);
406    _newest = this;
407}
408
409void
410Process::terminate()
411{
412    _terminated = true;
413    _suspendedReady = false;
414    _suspended = false;
415    _syncReset = false;
416    delete dynamicSensitivity;
417    dynamicSensitivity = nullptr;
418    for (auto s: staticSensitivities)
419        delete s;
420    staticSensitivities.clear();
421
422    _terminatedEvent.notify();
423
424    for (auto jw: joinWaiters)
425        jw->signal();
426    joinWaiters.clear();
427}
428
429Process *Process::_newest;
430
431void
432throw_it_wrapper(Process *p, ExceptionWrapperBase &exc, bool inc_kids)
433{
434    p->throw_it(exc, inc_kids);
435}
436
437} // namespace sc_gem5
438