static int SetThreadToPriority(pthread_t thread, UInt32 inPriority, Boolean inIsFixed, UInt64 period, UInt64 computation, UInt64 constraint)
{
if (inPriority == 96) {
// REAL-TIME / TIME-CONSTRAINT THREAD
thread_time_constraint_policy_data_t theTCPolicy;
theTCPolicy.period = period;
theTCPolicy.computation = computation;
theTCPolicy.constraint = constraint;
theTCPolicy.preemptible = true;
kern_return_t res = thread_policy_set(pthread_mach_thread_np(thread), THREAD_TIME_CONSTRAINT_POLICY, (thread_policy_t)&theTCPolicy, THREAD_TIME_CONSTRAINT_POLICY_COUNT);
return (res == KERN_SUCCESS) ? 0 : -1;
} else {
// OTHER THREADS
thread_extended_policy_data_t theFixedPolicy;
thread_precedence_policy_data_t thePrecedencePolicy;
SInt32 relativePriority;
// [1] SET FIXED / NOT FIXED
theFixedPolicy.timeshare = !inIsFixed;
thread_policy_set(pthread_mach_thread_np(thread), THREAD_EXTENDED_POLICY, (thread_policy_t)&theFixedPolicy, THREAD_EXTENDED_POLICY_COUNT);
// [2] SET PRECEDENCE
// N.B.: We expect that if thread A created thread B, and the program wishes to change
// the priority of thread B, then the call to change the priority of thread B must be
// made by thread A.
// This assumption allows us to use pthread_self() to correctly calculate the priority
// of the feeder thread (since precedency policy's importance is relative to the
// spawning thread's priority.)
relativePriority = inPriority - GetThreadSetPriority(pthread_self());
thePrecedencePolicy.importance = relativePriority;
kern_return_t res = thread_policy_set(pthread_mach_thread_np(thread), THREAD_PRECEDENCE_POLICY, (thread_policy_t)&thePrecedencePolicy, THREAD_PRECEDENCE_POLICY_COUNT);
return (res == KERN_SUCCESS) ? 0 : -1;
}
}
static int SetThreadToPriority(pthread_t thread, UInt32 inPriority, Boolean inIsFixed, UInt64 period, UInt64 computation, UInt64 constraint)
{
if (inPriority == 96) {
// REAL-TIME / TIME-CONSTRAINT THREAD
thread_time_constraint_policy_data_t theTCPolicy;
theTCPolicy.period = AudioConvertNanosToHostTime(period);
theTCPolicy.computation = AudioConvertNanosToHostTime(computation);
theTCPolicy.constraint = AudioConvertNanosToHostTime(constraint);
theTCPolicy.preemptible = true;
kern_return_t res = thread_policy_set(pthread_mach_thread_np(thread), THREAD_TIME_CONSTRAINT_POLICY, (thread_policy_t)&theTCPolicy, THREAD_TIME_CONSTRAINT_POLICY_COUNT);
return (res == KERN_SUCCESS) ? 0 : -1;
} else {
// OTHER THREADS
thread_extended_policy_data_t theFixedPolicy;
thread_precedence_policy_data_t thePrecedencePolicy;
SInt32 relativePriority;
theFixedPolicy.timeshare = !inIsFixed;
thread_policy_set(pthread_mach_thread_np(thread), THREAD_EXTENDED_POLICY, (thread_policy_t)&theFixedPolicy, THREAD_EXTENDED_POLICY_COUNT);
relativePriority = inPriority - GetThreadSetPriority(pthread_self());
thePrecedencePolicy.importance = relativePriority;
kern_return_t res = thread_policy_set(pthread_mach_thread_np(thread), THREAD_PRECEDENCE_POLICY, (thread_policy_t)&thePrecedencePolicy, THREAD_PRECEDENCE_POLICY_COUNT);
return (res == KERN_SUCCESS) ? 0 : -1;
}
}
