process.cc revision 13182:9e030f636a8c 
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_main.hh"
36#include "systemc/ext/core/sc_process_handle.hh"
37#include "systemc/ext/utils/sc_report_handler.hh"
38
39namespace sc_gem5
40{
41
42SensitivityTimeout::SensitivityTimeout(Process *p, ::sc_core::sc_time t) :
43    Sensitivity(p), timeoutEvent([this]() { this->timeout(); })
44{
45    scheduler.schedule(&timeoutEvent, t);
46}
47
48SensitivityTimeout::~SensitivityTimeout()
49{
50    if (timeoutEvent.scheduled())
51        scheduler.deschedule(&timeoutEvent);
52}
53
54void
55SensitivityTimeout::timeout()
56{
57    notify();
58}
59
60SensitivityEvent::SensitivityEvent(
61        Process *p, const ::sc_core::sc_event *e) : Sensitivity(p), event(e)
62{
63    Event::getFromScEvent(event)->addSensitivity(this);
64}
65
66SensitivityEvent::~SensitivityEvent()
67{
68    Event::getFromScEvent(event)->delSensitivity(this);
69}
70
71SensitivityEventAndList::SensitivityEventAndList(
72        Process *p, const ::sc_core::sc_event_and_list *list) :
73    Sensitivity(p), list(list), count(0)
74{
75    for (auto e: list->events)
76        Event::getFromScEvent(e)->addSensitivity(this);
77}
78
79SensitivityEventAndList::~SensitivityEventAndList()
80{
81    for (auto e: list->events)
82        Event::getFromScEvent(e)->delSensitivity(this);
83}
84
85void
86SensitivityEventAndList::notifyWork(Event *e)
87{
88    e->delSensitivity(this);
89    count++;
90    if (count == list->events.size())
91        process->satisfySensitivity(this);
92}
93
94SensitivityEventOrList::SensitivityEventOrList(
95        Process *p, const ::sc_core::sc_event_or_list *list) :
96    Sensitivity(p), list(list)
97{
98    for (auto e: list->events)
99        Event::getFromScEvent(e)->addSensitivity(this);
100}
101
102SensitivityEventOrList::~SensitivityEventOrList()
103{
104    for (auto e: list->events)
105        Event::getFromScEvent(e)->delSensitivity(this);
106}
107
108void
109SensitivityTimeoutAndEventAndList::notifyWork(Event *e)
110{
111    if (e) {
112        // An event went off which must be part of the sc_event_and_list.
113        SensitivityEventAndList::notifyWork(e);
114    } else {
115        // There's no inciting event, so this must be a timeout.
116        SensitivityTimeout::notifyWork(e);
117    }
118}
119
120
121class UnwindExceptionReset : public ::sc_core::sc_unwind_exception
122{
123  public:
124    UnwindExceptionReset() { _isReset = true; }
125};
126
127class UnwindExceptionKill : public ::sc_core::sc_unwind_exception
128{
129  public:
130    UnwindExceptionKill() {}
131};
132
133template <typename T>
134struct BuiltinExceptionWrapper : public ExceptionWrapperBase
135{
136  public:
137    T t;
138    void throw_it() override { throw t; }
139};
140
141BuiltinExceptionWrapper<UnwindExceptionReset> resetException;
142BuiltinExceptionWrapper<UnwindExceptionKill> killException;
143
144
145void
146Process::forEachKid(const std::function<void(Process *)> &work)
147{
148    for (auto &kid: get_child_objects()) {
149        Process *p_kid = dynamic_cast<Process *>(kid);
150        if (p_kid)
151            work(p_kid);
152    }
153}
154
155void
156Process::suspend(bool inc_kids)
157{
158    if (inc_kids)
159        forEachKid([](Process *p) { p->suspend(true); });
160
161    if (!_suspended) {
162        _suspended = true;
163        _suspendedReady = scheduler.suspend(this);
164
165        if (procKind() != ::sc_core::SC_METHOD_PROC_ &&
166                scheduler.current() == this) {
167            // This isn't in the spec, but Accellera says that a thread that
168            // self suspends should be marked ready immediately when it's
169            // resumed.
170            _suspendedReady = true;
171            scheduler.yield();
172        }
173    }
174}
175
176void
177Process::resume(bool inc_kids)
178{
179    if (inc_kids)
180        forEachKid([](Process *p) { p->resume(true); });
181
182    if (_suspended) {
183        _suspended = false;
184        if (_suspendedReady)
185            scheduler.resume(this);
186        _suspendedReady = false;
187    }
188}
189
190void
191Process::disable(bool inc_kids)
192{
193    if (inc_kids)
194        forEachKid([](Process *p) { p->disable(true); });
195
196    if (!::sc_core::sc_allow_process_control_corners &&
197            dynamic_cast<SensitivityTimeout *>(dynamicSensitivity)) {
198        std::string message("attempt to disable a thread with timeout wait: ");
199        message += name();
200        SC_REPORT_ERROR("Undefined process control interaction",
201                message.c_str());
202    }
203
204    _disabled = true;
205}
206
207void
208Process::enable(bool inc_kids)
209{
210
211    if (inc_kids)
212        forEachKid([](Process *p) { p->enable(true); });
213
214    _disabled = false;
215}
216
217void
218Process::kill(bool inc_kids)
219{
220    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
221        SC_REPORT_ERROR(
222                "(E572) a process may not be killed before it is initialized",
223                name());
224    }
225
226    // Propogate the kill to our children no matter what happens to us.
227    if (inc_kids)
228        forEachKid([](Process *p) { p->kill(true); });
229
230    // If we're in the middle of unwinding, ignore the kill request.
231    if (_isUnwinding)
232        return;
233
234    // Update our state.
235    terminate();
236    _isUnwinding = true;
237
238    // Make sure this process isn't marked ready
239    popListNode();
240
241    // Inject the kill exception into this process if it's started.
242    if (!_needsStart)
243        injectException(killException);
244}
245
246void
247Process::reset(bool inc_kids)
248{
249    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
250        SC_REPORT_ERROR(
251                "(E573) a process may not be asynchronously reset while"
252                "the simulation is not running", name());
253    }
254
255    // Propogate the reset to our children no matter what happens to us.
256    if (inc_kids)
257        forEachKid([](Process *p) { p->reset(true); });
258
259    // If we're in the middle of unwinding, ignore the reset request.
260    if (_isUnwinding)
261        return;
262
263
264    if (_needsStart) {
265        scheduler.runNow(this);
266    } else {
267        _isUnwinding = true;
268        injectException(resetException);
269    }
270
271    _resetEvent.notify();
272}
273
274void
275Process::throw_it(ExceptionWrapperBase &exc, bool inc_kids)
276{
277    if (::sc_core::sc_get_status() != ::sc_core::SC_RUNNING) {
278        SC_REPORT_ERROR(
279                "(E574) throw_it not allowed unless simulation is running ",
280                name());
281    }
282
283    if (inc_kids)
284        forEachKid([&exc](Process *p) { p->throw_it(exc, true); });
285
286    // Only inject an exception into threads that have started.
287    if (!_needsStart)
288        injectException(exc);
289}
290
291void
292Process::injectException(ExceptionWrapperBase &exc)
293{
294    excWrapper = &exc;
295    scheduler.runNow(this);
296};
297
298void
299Process::syncResetOn(bool inc_kids)
300{
301    if (inc_kids)
302        forEachKid([](Process *p) { p->syncResetOn(true); });
303
304    _syncReset = true;
305}
306
307void
308Process::syncResetOff(bool inc_kids)
309{
310    if (inc_kids)
311        forEachKid([](Process *p) { p->syncResetOff(true); });
312
313    _syncReset = false;
314}
315
316void
317Process::dontInitialize()
318{
319    scheduler.dontInitialize(this);
320}
321
322void
323Process::finalize()
324{
325    for (auto &s: pendingStaticSensitivities) {
326        s->finalize(staticSensitivities);
327        delete s;
328        s = nullptr;
329    }
330    pendingStaticSensitivities.clear();
331};
332
333void
334Process::run()
335{
336    bool reset;
337    do {
338        reset = false;
339        try {
340            func->call();
341        } catch(ScHalt) {
342            std::cout << "Terminating process " << name() << std::endl;
343        } catch(const ::sc_core::sc_unwind_exception &exc) {
344            reset = exc.is_reset();
345            _isUnwinding = false;
346        } catch (...) {
347            throw;
348        }
349    } while (reset);
350    needsStart(true);
351}
352
353void
354Process::addStatic(PendingSensitivity *s)
355{
356    pendingStaticSensitivities.push_back(s);
357}
358
359void
360Process::setDynamic(Sensitivity *s)
361{
362    delete dynamicSensitivity;
363    dynamicSensitivity = s;
364}
365
366void
367Process::satisfySensitivity(Sensitivity *s)
368{
369    // If there's a dynamic sensitivity and this wasn't it, ignore.
370    if (dynamicSensitivity && dynamicSensitivity != s)
371        return;
372
373    setDynamic(nullptr);
374    ready();
375}
376
377void
378Process::ready()
379{
380    if (disabled())
381        return;
382    if (suspended())
383        _suspendedReady = true;
384    else
385        scheduler.ready(this);
386}
387
388void
389Process::lastReport(::sc_core::sc_report *report)
390{
391    if (report) {
392        _lastReport = std::unique_ptr<::sc_core::sc_report>(
393                new ::sc_core::sc_report(*report));
394    } else {
395        _lastReport = nullptr;
396    }
397}
398
399::sc_core::sc_report *Process::lastReport() const { return _lastReport.get(); }
400
401Process::Process(const char *name, ProcessFuncWrapper *func, bool internal) :
402    ::sc_core::sc_process_b(name), excWrapper(nullptr), func(func),
403    _internal(internal), _needsStart(true), _isUnwinding(false),
404    _terminated(false), _suspended(false), _disabled(false), _syncReset(false),
405    refCount(0), stackSize(::Fiber::DefaultStackSize),
406    dynamicSensitivity(nullptr)
407{
408    _dynamic =
409            (::sc_core::sc_get_status() >
410             ::sc_core::SC_BEFORE_END_OF_ELABORATION);
411    _newest = this;
412}
413
414void
415Process::terminate()
416{
417    _terminated = true;
418    _suspendedReady = false;
419    _suspended = false;
420    _syncReset = false;
421    delete dynamicSensitivity;
422    dynamicSensitivity = nullptr;
423    for (auto s: staticSensitivities)
424        delete s;
425    staticSensitivities.clear();
426
427    _terminatedEvent.notify();
428}
429
430Process *Process::_newest;
431
432void
433throw_it_wrapper(Process *p, ExceptionWrapperBase &exc, bool inc_kids)
434{
435    p->throw_it(exc, inc_kids);
436}
437
438} // namespace sc_gem5
439