gem5/util/systemc/sc_gem5_control.cc
Andrew Bardsley e5e5b80690 config: Fix to SystemC example's event handling
This patch fixes checkpoint restore in the SystemC hosting example by handling
early PollEvent events correctly before any EventQueue events are posted.

The SystemC event queue handler (SCEventQueue) reports an error if the event
loop is entered with no Events posted.  It is possible for this to happen
after instantiate due to PollEvent events.  This patch separates out
`external' events into a different handler in sc_module.cc to prevent the
error from occurring.

This fix also improves the event handling of asynchronous events by:

    1) Making asynchronous events 'catch up' gem5 time to SystemC
        time to avoid the appearance that events have been lost
        while servicing an asynchronous event that schedules an
        event loop exit event

    2) Add an in_simulate data member to Module to allow the event
        loop to check whether events should be processed or deferred
        until the next time Module::simulate is entered

    3) Cancel pending events around the entry/exit of the event loop
        in Module::simulate

    4) Moving the state initialisation of the example entirely into
        run to correct a problem with early events in checkpoint
        restore.

It is still possible to schedule asynchronous events (and talk PollQueue
actions) while simulate is not running.  This behaviour may stil cause
some problems.
2014-12-02 06:08:09 -05:00

310 lines
8.3 KiB
C++

/*
* Copyright (c) 2014 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Andrew Bardsley
*/
#include <cstdlib>
#include <iostream>
#include <list>
#include "base/statistics.hh"
#include "sim/cxx_config_ini.hh"
#include "sim/cxx_manager.hh"
#include "sim/debug.hh"
#include "sim/init_signals.hh"
#include "sim/stat_control.hh"
#include "sc_gem5_control.hh"
#include "sc_logger.hh"
#include "sc_module.hh"
#include "stats.hh"
namespace Gem5SystemC
{
/** This is the private side of Gem5Control */
class Gem5TopLevelModule : public Gem5SystemC::Module
{
friend class Gem5Control;
protected:
CxxConfigFileBase *config_file;
CxxConfigManager *root_manager;
Gem5SystemC::Logger logger;
/** Things to do at end_of_elaborate */
std::list<void (*)()> endOfElaborationFuncs;
public:
SC_HAS_PROCESS(Gem5TopLevelModule);
Gem5TopLevelModule(sc_core::sc_module_name name,
const std::string &config_filename);
~Gem5TopLevelModule();
/** gem5 simulate. @todo for more interesting simulation control,
* this needs to be more complicated */
void run();
/* Register an action to happen at the end of elaboration */
void registerEndOfElaboration(void (*func)())
{
endOfElaborationFuncs.push_back(func);
}
/** SystemC startup */
void end_of_elaboration();
};
Gem5System::Gem5System(CxxConfigManager *manager_,
const std::string &system_name, const std::string &instance_name) :
manager(manager_),
systemName(system_name),
instanceName(instance_name)
{
manager->addRenaming(CxxConfigManager::Renaming(
system_name, instance_name));
}
Gem5System::~Gem5System()
{
delete manager;
}
void
Gem5System::setParam(const std::string &object,
const std::string &param_name, const std::string &param_value)
{
manager->setParam(systemName + (object != "" ? "." + object : ""),
param_name, param_value);
}
void
Gem5System::setParamVector(const std::string &object,
const std::string &param_name,
const std::vector<std::string> &param_values)
{
manager->setParamVector(systemName +
(object != "" ? "." + object : ""), param_name, param_values);
}
void
Gem5System::instantiate()
{
try {
/* Make a new System */
SimObject *obj = manager->findObject(systemName, true);
/* Add the System's objects to the list of managed
* objects for initialisation */
manager->findTraversalOrder(systemName);
/* Bound ports *must* be internal to System */
for (auto i = manager->objectsInOrder.begin();
i != manager->objectsInOrder.end();
++ i)
{
manager->bindObjectPorts(*i);
}
/* gem5 startup sequence */
manager->instantiate(false);
manager->initState();
manager->startup();
} catch (CxxConfigManager::Exception &e) {
fatal("Config problem in Gem5System: %s: %s",
e.name, e.message);
}
}
Gem5Control::Gem5Control(const std::string &config_filename)
{
module = new Gem5TopLevelModule("gem5", config_filename);
}
Gem5Control::~Gem5Control()
{ }
void
Gem5Control::registerEndOfElaboration(void (*func)())
{
module->registerEndOfElaboration(func);
}
void
Gem5Control::setDebugFlag(const char *flag)
{
::setDebugFlag(flag);
}
void
Gem5Control::clearDebugFlag(const char *flag)
{
::clearDebugFlag(flag);
}
void
Gem5Control::setRemoteGDBPort(unsigned int port)
{
::setRemoteGDBPort(port);
}
Gem5System *
Gem5Control::makeSystem(const std::string &system_name,
const std::string &instance_name)
{
Gem5System *ret = new Gem5System(
new CxxConfigManager(*(module->config_file)),
system_name, instance_name);
return ret;
}
const std::string &
Gem5Control::getVersion() const
{
return version;
}
void
Gem5Control::setVersion(const std::string &new_version)
{
if (version != "")
fatal("Gem5Control::setVersion called for a second time");
version = new_version;
}
Gem5TopLevelModule::Gem5TopLevelModule(sc_core::sc_module_name name,
const std::string &config_filename) :
Gem5SystemC::Module(name),
config_file(NULL),
root_manager(NULL)
{
SC_THREAD(run);
cxxConfigInit();
/* Pass DPRINTF messages to SystemC */
Trace::setDebugLogger(&logger);
/* @todo need this as an option */
Gem5SystemC::setTickFrequency();
/* Make a SystemC-synchronising event queue and install it as the
* sole top level gem5 EventQueue */
Gem5SystemC::Module::setupEventQueues(*this);
if (sc_core::sc_get_time_resolution() !=
sc_core::sc_time(1, sc_core::SC_PS))
{
fatal("Time resolution must be set to 1 ps for gem5 to work");
}
/* Enable keyboard interrupt, async I/O etc. */
initSignals();
/* Enable stats */
Stats::initSimStats();
Stats::registerHandlers(CxxConfig::statsReset, CxxConfig::statsDump);
Trace::enabled = true;
config_file = new CxxIniFile();
if (!config_file->load(config_filename)) {
fatal("Gem5TopLevelModule: Can't open config file: %s",
config_filename);
}
root_manager = new CxxConfigManager(*config_file);
CxxConfig::statsEnable();
/* Make the root object */
try {
SimObject *root = root_manager->findObject("root", false);
/* Make sure we don't traverse into root's children */
root_manager->objectsInOrder.push_back(root);
root_manager->instantiate(false);
root_manager->initState();
root_manager->startup();
} catch (CxxConfigManager::Exception &e) {
fatal("Config problem in Gem5TopLevelModule: %s: %s",
e.name, e.message);
}
}
Gem5TopLevelModule::~Gem5TopLevelModule()
{
delete config_file;
delete root_manager;
}
void
Gem5TopLevelModule::run()
{
GlobalSimLoopExitEvent *exit_event = NULL;
exit_event = simulate();
std::cerr << "Exit at tick " << curTick()
<< ", cause: " << exit_event->getCause() << '\n';
getEventQueue(0)->dump();
}
void
Gem5TopLevelModule::end_of_elaboration()
{
for (auto i = endOfElaborationFuncs.begin();
i != endOfElaborationFuncs.end(); ++i)
{
(*i)();
}
}
}
Gem5SystemC::Gem5Control *
makeGem5Control(const std::string &config_filename)
{
return new Gem5SystemC::Gem5Control(config_filename);
}