inline void setState(qi::Atomic<int>& state, TaskState from, TaskState to, TaskState from2, TaskState to2)
{
for (unsigned i=0; i<1000; ++i)
if (state.setIfEquals(from, to) || state.setIfEquals(from2, to2))
return;
while (true)
{
for (unsigned i=0; i<1000; ++i)
{
if (state.setIfEquals(from, to) || state.setIfEquals(from2, to2))
return;
qi::os::msleep(1); // TODO: 1ms is probably too long
}
qiLogWarning() << "PeriodicTask is stuck " << from << ' ' << to << ' ' << from2 << ' ' << to2 << ' '<< *state;
}
}
void PeriodicTaskPrivate::_reschedule(qi::int64_t delay)
{
qiLogDebug() << _name <<" rescheduling in " << delay;
_task = getEventLoop()->async(boost::bind(&PeriodicTaskPrivate::_wrap, shared_from_this()), delay);
if (!_state.setIfEquals(Task_Rescheduling, Task_Scheduled))
qiLogError() << "PeriodicTask forbidden state change while rescheduling " << *_state;
}
void PeriodicTaskPrivate::_trigger(qi::Future<void> future)
{
// if future was not canceled, the task already ran, don't retrigger
if (!future.isCanceled())
return;
// else, start the task now if we are still triggering
if (_state.setIfEquals(Task_Triggering, Task_Rescheduling))
_reschedule(0);
}
void Application::stop()
{
static qi::Atomic<bool> atStopHandlerCall = false;
if (atStopHandlerCall.setIfEquals(false, true))
{
FunctionList& fl = lazyGet(globalAtStop);
qiLogDebug() << "Executing " << fl.size() << " atStop handlers";
for (FunctionList::iterator i = fl.begin(); i!= fl.end(); ++i)
{
try
{
(*i)();
}
catch (std::exception& e)
{
qiLogError() << "Application atStop callback throw the following error: " << e.what();
}
}
globalIsStop = true;
globalCond.notify_all();
}
}
void PeriodicTaskPrivate::_wrap()
{
if (*_state == Task_Stopped)
qiLogError() << "PeriodicTask inconsistency: stopped from callback";
/* To avoid being stuck because of unhandled transition, the rule is
* that any other thread playing with our state can only do so
* to stop us, and must eventualy reach the Stopping state
*/
if (_state.setIfEquals(Task_Stopping, Task_Stopped))
return;
/* reschedule() needs to call async() before reseting state from rescheduling
* to scheduled, to protect the _task object. So we might still be
* in rescheduling state here.
*/
while (*_state == Task_Rescheduling)
boost::this_thread::yield();
// order matters! check scheduled state first as the state cannot change
// from triggering to scheduled but can change in the other way
if (!_state.setIfEquals(Task_Scheduled, Task_Running) &&
!_state.setIfEquals(Task_Triggering, Task_Running))
{
setState(_state, Task_Stopping, Task_Stopped);
return;
}
bool shouldAbort = false;
qi::int64_t wall = 0, now=0, delta=0;
qi::int64_t usr, sys;
bool compensate = _compensateCallTime; // we don't want that bool to change in the middle
try
{
wall = qi::os::ustime();
std::pair<qi::int64_t, qi::int64_t> cpu = qi::os::cputime();
_tid = os::gettid();
_callback();
_tid = invalidThreadId;
now = qi::os::ustime();
wall = now - wall;
std::pair<qi::int64_t, qi::int64_t> cpu2 = qi::os::cputime();
usr = cpu2.first - cpu.first;
sys = cpu2.second - cpu.second;
if (compensate)
delta = wall;
}
catch (const std::exception& e)
{
qiLogInfo() << "Exception in task " << _name << ": " << e.what();
shouldAbort = true;
}
catch(...)
{
qiLogInfo() << "Unknown exception in task callback.";
shouldAbort = true;
}
if (shouldAbort)
{
setState(_state, Task_Stopping, Task_Stopped,
Task_Running, Task_Stopped);
return;
}
else
{
_callStats.push((float)wall / 1e6f, (float)usr / 1e6f, (float)sys / 1e6f);
if (now - _statsDisplayTime >= 20000000)
{
float secTime = float(now - _statsDisplayTime) / 1e6f;
_statsDisplayTime = now;
unsigned int count = _callStats.count();
std::string catName = "stats." + _name;
qiLogVerbose(catName.c_str())
<< (_callStats.user().cumulatedValue() * 100.0 / secTime)
<< "% "
<< count
<< " " << _callStats.wall().asString(count)
<< " " << _callStats.user().asString(count)
<< " " << _callStats.system().asString(count)
;
_callStats.reset();
}
if (!_state.setIfEquals(Task_Running, Task_Rescheduling))
{ // If we are not in running state anymore, someone switched us
// to stopping
setState(_state, Task_Stopping, Task_Stopped);
return;
}
_reschedule(std::max((qi::int64_t)0, _usPeriod - delta));
}
}