void run_simulation(int algorithm, int quantum)
{
switch(algorithm) {
case STRIDE:
stride_scheduling(quantum);
break;
case PS:
priority_scheduling();
break;
case RR:
rr_scheduling(quantum);
break;
case FCFS:
default:
first_come_first_serve();
break;
}
}
void priority_scheduling()
{
int current_task = 0;
int current_tick = 0;
int highest_priority = 0;
int lowest_time = 999;
int i;
for (i=0;i<num_tasks;i++){
if (tasks[i].priority > highest_priority&&tasks[i].finish_time == 0){
highest_priority = tasks[i].priority;
}
}
for (i=0;i<num_tasks;i++){
if(tasks[i].priority == highest_priority&&tasks[i].finish_time == 0){
if (tasks[i].arrival_time <= lowest_time&&tasks[i].finish_time == 0){
lowest_time = tasks[i].arrival_time;
}
}
}
for (i=0;i<num_tasks;i++){
if(tasks[i].priority == highest_priority && lowest_time == tasks[i].arrival_time &&tasks[i].finish_time == 0){
tasks[i].schedulings +=1;
for(;;){
current_tick +=1;
tasks[i].cpu_cycles +=1;
if (tasks[i].cpu_cycles >= tasks[i].length) {
float quantum_fragment = tasks[i].cpu_cycles -
tasks[current_task].length;
tasks[i].cpu_cycles = tasks[i].length;
tasks[i].finish_time = current_tick - quantum_fragment;
tasks[i].schedulings = 1;
i++;
if (i > num_tasks) {
break;
}
tasks[i].cpu_cycles += quantum_fragment;
count++;
if (count==num_tasks)
{
compute_and_print_stats();
exit(0);
}
priority_scheduling();
}
}
}
}
}
