static void CallbackUpdate( PaAlsaThreading *th )
{
th->callbackTime = PaUtil_GetTime();
th->callbackCpuTime = PaUtil_GetCpuLoad( th->cpuLoadMeasurer );
}
static double GetStreamCpuLoad( PaStream* s )
{
PaSkeletonStream *stream = (PaSkeletonStream*)s;
return PaUtil_GetCpuLoad( &stream->cpuLoadMeasurer );
}
static void *WatchdogFunc( void *userData )
{
PaError result = paNoError, *pres = NULL;
int err;
PaAlsaThreading *th = (PaAlsaThreading *) userData;
unsigned intervalMsec = 500;
const PaTime maxSeconds = 3.; /* Max seconds between callbacks */
PaTime timeThen = PaUtil_GetTime(), timeNow, timeElapsed, cpuTimeThen, cpuTimeNow, cpuTimeElapsed;
double cpuLoad, avgCpuLoad = 0.;
int throttled = 0;
assert( th );
/* Execute OnWatchdogExit when exiting */
pthread_cleanup_push( &OnWatchdogExit, th );
/* Boost priority of callback thread */
PA_ENSURE( result = BoostPriority( th ) );
if( !result )
{
/* Boost failed, might as well exit */
pthread_exit( NULL );
}
cpuTimeThen = th->callbackCpuTime;
{
int policy;
struct sched_param spm = { 0 };
pthread_getschedparam( pthread_self(), &policy, &spm );
PA_DEBUG(( "%s: Watchdog priority is %d\n", __FUNCTION__, spm.sched_priority ));
}
while( 1 )
{
double lowpassCoeff = 0.9, lowpassCoeff1 = 0.99999 - lowpassCoeff;
/* Test before and after in case whatever underlying sleep call isn't interrupted by pthread_cancel */
pthread_testcancel();
Pa_Sleep( intervalMsec );
pthread_testcancel();
if( PaUtil_GetTime() - th->callbackTime > maxSeconds )
{
PA_DEBUG(( "Watchdog: Terminating callback thread\n" ));
/* Tell thread to terminate */
err = pthread_kill( th->callbackThread, SIGKILL );
pthread_exit( NULL );
}
PA_DEBUG(( "%s: PortAudio reports CPU load: %g\n", __FUNCTION__, PaUtil_GetCpuLoad( th->cpuLoadMeasurer ) ));
/* Check if we should throttle, or unthrottle :P */
cpuTimeNow = th->callbackCpuTime;
cpuTimeElapsed = cpuTimeNow - cpuTimeThen;
cpuTimeThen = cpuTimeNow;
timeNow = PaUtil_GetTime();
timeElapsed = timeNow - timeThen;
timeThen = timeNow;
cpuLoad = cpuTimeElapsed / timeElapsed;
avgCpuLoad = avgCpuLoad * lowpassCoeff + cpuLoad * lowpassCoeff1;
/*
if( throttled )
PA_DEBUG(( "Watchdog: CPU load: %g, %g\n", avgCpuLoad, cpuTimeElapsed ));
*/
if( PaUtil_GetCpuLoad( th->cpuLoadMeasurer ) > .925 )
{
static int policy;
static struct sched_param spm = { 0 };
static const struct sched_param defaultSpm = { 0 };
PA_DEBUG(( "%s: Throttling audio thread, priority %d\n", __FUNCTION__, spm.sched_priority ));
pthread_getschedparam( th->callbackThread, &policy, &spm );
if( !pthread_setschedparam( th->callbackThread, SCHED_OTHER, &defaultSpm ) )
{
throttled = 1;
}
else
PA_DEBUG(( "Watchdog: Couldn't lower priority of audio thread: %s\n", strerror( errno ) ));
/* Give other processes a go, before raising priority again */
PA_DEBUG(( "%s: Watchdog sleeping for %lu msecs before unthrottling\n", __FUNCTION__, th->throttledSleepTime ));
Pa_Sleep( th->throttledSleepTime );
/* Reset callback priority */
if( pthread_setschedparam( th->callbackThread, SCHED_FIFO, &spm ) != 0 )
{
PA_DEBUG(( "%s: Couldn't raise priority of audio thread: %s\n", __FUNCTION__, strerror( errno ) ));
}
if( PaUtil_GetCpuLoad( th->cpuLoadMeasurer ) >= .99 )
intervalMsec = 50;
else
intervalMsec = 100;
/*
lowpassCoeff = .97;
lowpassCoeff1 = .99999 - lowpassCoeff;
*/
}
else if( throttled && avgCpuLoad < .8 )
{
intervalMsec = 500;
throttled = 0;
/*
lowpassCoeff = .9;
lowpassCoeff1 = .99999 - lowpassCoeff;
*/
}
}
pthread_cleanup_pop( 1 ); /* Execute cleanup on exit */
error:
/* Shouldn't get here in the normal case */
/* Pass on error code */
pres = malloc( sizeof (PaError) );
*pres = result;
pthread_exit( pres );
}
