59 lines
1.4 KiB
C
59 lines
1.4 KiB
C
#include <defs.h>
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#include <list.h>
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#include <proc.h>
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#include <assert.h>
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#include <default_sched.h>
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static void
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RR_init(struct run_queue *rq) {
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list_init(&(rq->run_list));
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rq->proc_num = 0;
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}
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static void
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RR_enqueue(struct run_queue *rq, struct proc_struct *proc) {
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assert(list_empty(&(proc->run_link)));
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list_add_before(&(rq->run_list), &(proc->run_link));
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if (proc->time_slice == 0 || proc->time_slice > rq->max_time_slice) {
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proc->time_slice = rq->max_time_slice;
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}
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proc->rq = rq;
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rq->proc_num ++;
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}
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static void
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RR_dequeue(struct run_queue *rq, struct proc_struct *proc) {
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assert(!list_empty(&(proc->run_link)) && proc->rq == rq);
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list_del_init(&(proc->run_link));
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rq->proc_num --;
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}
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static struct proc_struct *
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RR_pick_next(struct run_queue *rq) {
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list_entry_t *le = list_next(&(rq->run_list));
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if (le != &(rq->run_list)) {
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return le2proc(le, run_link);
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}
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return NULL;
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}
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static void
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RR_proc_tick(struct run_queue *rq, struct proc_struct *proc) {
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if (proc->time_slice > 0) {
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proc->time_slice --;
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}
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if (proc->time_slice == 0) {
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proc->need_resched = 1;
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}
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}
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struct sched_class default_sched_class = {
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.name = "RR_scheduler",
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.init = RR_init,
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.enqueue = RR_enqueue,
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.dequeue = RR_dequeue,
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.pick_next = RR_pick_next,
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.proc_tick = RR_proc_tick,
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};
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