1
Files
lecture-operating-system-de…/c_os/user/demo/PreemptiveThreadDemo.cc

33 lines
790 B
C++

#include "user/demo/PreemptiveThreadDemo.h"
Semaphore PreemptiveLoopThread::sem(1);
void PreemptiveLoopThread::run() {
int cnt = 0;
while (true) {
// Basic synchronization by semaphore
sem.p();
// Saving + restoring kout position doesn't help much as preemption still occurs
kout.setpos(55, this->id);
kout << fillw(3) << this->id << fillw(0) << ": " << dec << cnt++ << endl;
sem.v();
}
}
void PreemptiveThreadDemo::run() {
kout.clear();
kout << "Preemptive Thread Demo:" << endl;
kout << "Readying LoopThreads" << endl;
for (unsigned int i = 0; i < this->number_of_threads; ++i) {
scheduler.ready<PreemptiveLoopThread>(i);
}
kout << "Exiting main thread" << endl;
scheduler.exit();
}