void Writer( void * arg )
{
struct LOCKING_CONTEXT block;
INDEX sequenceIndex=0;
INDEX index;
LockingInit( &block, LockingBlockNonBlocking, LockingWakeNonBlocking );
while(1)
{
ResourceLockExclusive( &BufferLock, &block);
while( !LockingIsAcquired( &block ) );
//resource should be exlusive
ASSERT( BufferLock.State == RESOURCE_EXCLUSIVE );
sequenceIndex++;
sequenceIndex%=SEQUENCE_LENGTH;
for( index = 0; index < BUFFER_SIZE; index++ )
{
Buffer[index] = index + Sequence[ sequenceIndex ] ;
}
ResourceUnlockExclusive( &BufferLock );
SchedulerStartCritical();
TimesWritten++;
SchedulerForceSwitch();
}
}
void Reader( void * arg )
{
INDEX index;
int first,second;
BOOL ready = FALSE;
while( ! ready )
{
SchedulerStartCritical();
if( TimesWritten > 0 )
{
ready = TRUE;
SchedulerEndCritical();
}
else
{
SchedulerForceSwitch();
}
}
while(1)
{
ResourceLockShared( &BufferLock, NULL );
//the resource should be shared
ASSERT( BufferLock.State == RESOURCE_SHARED );
for(index=1 ; index < BUFFER_SIZE; index++)
{
first = Buffer[index-1];
second = Buffer[index];
if( (first +1) != second )
{
KernelPanic( );
}
}
ResourceUnlockShared( &BufferLock );
SchedulerStartCritical();
TimesRead++;
SchedulerForceSwitch();
}
}
void StallThreadMain( void * arg )
{
while(TRUE)
{
if(StallCount != 0 )
{
KernelPanic();
}
StallCount++;
TotalStall++;
SchedulerStartCritical();
SchedulerBlockThread();
SchedulerForceSwitch();
}
//We should never get here.
KernelPanic();
}
