2003/0228/port/proc.c (diff list | history)

2003/0228/sys/src/9/port/proc.c:192,197 – 2003/0301/sys/src/9/port/proc.c:192,211 (short | long | prev | next)
Scheduling tweak: even prioritized processes get penalized for running too long. Bug fix: need to scan run queues twice, once again after lock acquired. rsc Mon Mar 20 20:49:42 2006
2003/0228		return 0; }
1995/0110
2003/0301		/* * ready(p) picks a new priority for a process and sticks it in the * runq for that priority. * * - fixed priority processes never move * - a process that uses all its quanta before blocking goes down a * priority level * - a process that uses less than half its quanta before blocking * goes up a priority level * - a process that blocks after using up half or more of it's quanta * stays at the same level * * new quanta are assigned each time a process blocks or changes level */
1990/0227		void ready(Proc *p) {
2003/0228/sys/src/9/port/proc.c:214,228 – 2003/0301/sys/src/9/port/proc.c:228,235
2003/0228		} else if(p->state == Running){ if(p->quanta <= 0){ /* degrade priority of anyone that used their whole quanta */                  /* processes > PriNormal and those below don't mix */ if(p->basepri > PriNormal){ if(pri > PriNormal) pri--; } else { if(pri > 0) pri--; }
2003/0301		if(pri > 0) pri--;
2003/0228		p->quanta = quanta[pri]; }
1995/0110		} else {
2003/0228/sys/src/9/port/proc.c:256,262 – 2003/0301/sys/src/9/port/proc.c:263,269
1990/0227		runproc(void) {
2003/0228		Schedq *rq;
1995/0110		Proc *p, *l;
2003/0301		Proc *p, *l, *tp;
2002/0822		ulong start, now;
2003/0228		int i;
1990/0227
2003/0228/sys/src/9/port/proc.c:274,292 – 2003/0301/sys/src/9/port/proc.c:281,301
1992/0603		spllo();
2003/0228		for(i = 0;; i++){ /* * get highest priority process that this
2003/0301		* find the highest priority target process that this
2003/0228		* processor can run given affinity constraints */ for(rq = &runq[Nrq-1]; rq >= runq; rq--){ p = rq->head; if(p == 0)
2003/0301		tp = rq->head; if(tp == 0)
2003/0228		continue; for(; p; p = p->rnext){ if(p->mp == MACHP(m->machno) || (!p->wired && i > 0))
2003/0301		for(; tp; tp = tp->rnext){ if(tp->mp == nil || tp->mp == MACHP(m->machno) || (!tp->wired && i > 0))
2003/0228		goto found;
1998/0901		}
1995/0110		}
2002/0822
2003/0301		/* waste time or halt the CPU */
2000/1130		idlehands();
2003/0228		/* remember how much time we're here */
2003/0228/sys/src/9/port/proc.c:300,308 – 2003/0301/sys/src/9/port/proc.c:309,321
1997/0821		if(!canlock(runq)) goto loop;
1991/0420
2003/0301		/* * the queue may have changed before we locked runq, * refind the target process. */
1995/0110		l = 0; for(p = rq->head; p; p = p->rnext){
2003/0228		if(p->mp == MACHP(m->machno) || (!p->wired && i > 0))
2003/0301		if(p == tp)
1995/0110		break; l = p;
1994/0728		}