#include #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "../port/error.h" #include "edf.h" #include int coopsched; int schedgain = 30; /* units in seconds */ int nrdy; Ref noteidalloc; void updatecpu(Proc*); int reprioritize(Proc*); ulong delayedscheds; /* statistics */ long skipscheds; long preempts; ulong load; static Ref pidalloc; static struct Procalloc { Lock; Proc* ht[128]; Proc* arena; Proc* free; } procalloc; enum { Q=10, DQ=4, Scaling=2, }; Schedq runq[Nrq]; ulong runvec; char *statename[] = { /* BUG: generate automatically */ "Dead", "Moribund", "Ready", "Scheding", "Running", "Queueing", "QueueingR", "QueueingW", "Wakeme", "Broken", "Stopped", "Rendez", "Waitrelease", }; static void pidhash(Proc*); static void pidunhash(Proc*); static void rebalance(void); /* * Always splhi()'ed. */ void schedinit(void) /* never returns */ { Edf *e; setlabel(&m->sched); if(up) { if((e = up->edf) && (e->flags & Admitted)) edfrecord(up); m->proc = 0; switch(up->state) { case Running: ready(up); break; case Moribund: up->state = Dead; edfstop(up); if (up->edf) free(up->edf); up->edf = nil; /* * Holding locks from pexit: * procalloc * palloc */ mmurelease(up); up->qnext = procalloc.free; procalloc.free = up; unlock(&palloc); unlock(&procalloc); break; } up->mach = nil; updatecpu(up); up = nil; } sched(); } /* * If changing this routine, look also at sleep(). It * contains a copy of the guts of sched(). */ void sched(void) { Proc *p; if(m->ilockdepth) panic("ilockdepth %d, last lock 0x%p at 0x%lux, sched called from 0x%lux", m->ilockdepth, up?up->lastilock:nil, (up && up->lastilock)?up->lastilock->pc:0, getcallerpc(&p+2)); if(up){ if(up->nlocks.ref && up->state != Moribund && up->delaysched < 20){ up->delaysched++; delayedscheds++; return; } up->delaysched = 0; splhi(); /* statistics */ m->cs++; procsave(up); if(setlabel(&up->sched)){ procrestore(up); spllo(); return; } gotolabel(&m->sched); } p = runproc(); if(!p->edf){ updatecpu(p); p->priority = reprioritize(p); } if(p != m->readied) m->schedticks = m->ticks + HZ/10; m->readied = 0; up = p; up->state = Running; up->mach = MACHP(m->machno); m->proc = up; mmuswitch(up); gotolabel(&up->sched); } int anyready(void) { return runvec; } int anyhigher(void) { return runvec & ~((1<<(up->priority+1))-1); } /* * here once per clock tick to see if we should resched */ void hzsched(void) { /* once a second, rebalance will reprioritize ready procs */ if(m->machno == 0) rebalance(); /* unless preempted, get to run for at least 100ms */ if(anyhigher() || (!up->fixedpri && m->ticks > m->schedticks && anyready())){ m->readied = nil; /* avoid cooperative scheduling */ up->delaysched++; } } /* * here at the end of non-clock interrupts to see if we should preempt the * current process. Returns 1 if preempted, 0 otherwise. */ int preempted(void) { if(up && up->state == Running) if(up->preempted == 0) if(anyhigher()) if(!active.exiting){ m->readied = nil; /* avoid cooperative scheduling */ up->preempted = 1; sched(); splhi(); up->preempted = 0; return 1; } return 0; } /* * Update the cpu time average for this particular process, * which is about to change from up -> not up or vice versa. * p->lastupdate is the last time an updatecpu happened. * * The cpu time average is a decaying average that lasts * about D clock ticks. D is chosen to be approximately * the cpu time of a cpu-intensive "quick job". A job has to run * for approximately D clock ticks before we home in on its * actual cpu usage. Thus if you manage to get in and get out * quickly, you won't be penalized during your burst. Once you * start using your share of the cpu for more than about D * clock ticks though, your p->cpu hits 1000 (1.0) and you end up * below all the other quick jobs. Interactive tasks, because * they basically always use less than their fair share of cpu, * will be rewarded. * * If the process has not been running, then we want to * apply the filter * * cpu = cpu * (D-1)/D * * n times, yielding * * cpu = cpu * ((D-1)/D)^n * * but D is big enough that this is approximately * * cpu = cpu * (D-n)/D * * so we use that instead. * * If the process has been running, we apply the filter to * 1 - cpu, yielding a similar equation. Note that cpu is * stored in fixed point (* 1000). * * Updatecpu must be called before changing up, in order * to maintain accurate cpu usage statistics. It can be called * at any time to bring the stats for a given proc up-to-date. */ void updatecpu(Proc *p) { int n, t, ocpu; int D = schedgain*HZ*Scaling; if(p->edf) return; t = MACHP(0)->ticks*Scaling + Scaling/2; n = t - p->lastupdate; p->lastupdate = t; if(n == 0) return; if(n > D) n = D; ocpu = p->cpu; if(p != up) p->cpu = (ocpu*(D-n))/D; else{ t = 1000 - ocpu; t = (t*(D-n))/D; p->cpu = 1000 - t; } //iprint("pid %d %s for %d cpu %d -> %d\n", p->pid,p==up?"active":"inactive",n, ocpu,p->cpu); } /* * On average, p has used p->cpu of a cpu recently. * Its fair share is conf.nmach/m->load of a cpu. If it has been getting * too much, penalize it. If it has been getting not enough, reward it. * I don't think you can get much more than your fair share that * often, so most of the queues are for using less. Having a priority * of 3 means you're just right. Having a higher priority (up to p->basepri) * means you're not using as much as you could. */ int reprioritize(Proc *p) { int fairshare, n, load, ratio; load = MACHP(0)->load; if(load == 0) return p->basepri; /* * fairshare = 1.000 * conf.nproc * 1.000/load, * except the decimal point is moved three places * on both load and fairshare. */ fairshare = (conf.nmach*1000*1000)/load; n = p->cpu; if(n == 0) n = 1; ratio = (fairshare+n/2) / n; if(ratio > p->basepri) ratio = p->basepri; if(ratio < 0) panic("reprioritize"); //iprint("pid %d cpu %d load %d fair %d pri %d\n", p->pid, p->cpu, load, fairshare, ratio); return ratio; } /* * add a process to a scheduling queue */ void queueproc(Schedq *rq, Proc *p) { int pri; pri = rq - runq; lock(runq); p->priority = pri; p->rnext = 0; if(rq->tail) rq->tail->rnext = p; else rq->head = p; rq->tail = p; rq->n++; nrdy++; runvec |= 1<head; p; p = p->rnext){ if(p == tp) break; l = p; } /* * p->mach==0 only when process state is saved */ if(p == 0 || p->mach){ unlock(runq); return nil; } if(p->rnext == 0) rq->tail = l; if(l) l->rnext = p->rnext; else rq->head = p->rnext; if(rq->head == nil) runvec &= ~(1<<(rq-runq)); rq->n--; nrdy--; if(p->state != Ready) print("dequeueproc %s %lud %s\n", p->text, p->pid, statename[p->state]); unlock(runq); return p; } /* * ready(p) picks a new priority for a process and sticks it in the * runq for that priority. */ void ready(Proc *p) { int s, pri; Schedq *rq; void (*pt)(Proc*, int, vlong); s = splhi(); if(edfready(p)){ splx(s); return; } if(up != p) m->readied = p; /* group scheduling */ updatecpu(p); pri = reprioritize(p); p->priority = pri; rq = &runq[pri]; p->state = Ready; queueproc(rq, p); pt = proctrace; if(pt) pt(p, SReady, 0); splx(s); } /* * yield the processor and drop our priority */ void yield(void) { if(anyready()){ /* pretend we just used 1/2 tick */ up->lastupdate -= Scaling/2; sched(); } } /* * recalculate priorities once a second. We need to do this * since priorities will otherwise only be recalculated when * the running process blocks. */ ulong balancetime; static void rebalance(void) { int pri, npri, t, x; Schedq *rq; Proc *p; t = m->ticks; if(t - balancetime < HZ) return; balancetime = t; for(pri=0, rq=runq; prihead; if(p == nil) continue; if(p->mp != MACHP(m->machno)) continue; if(pri == p->basepri) continue; updatecpu(p); npri = reprioritize(p); if(npri != pri){ x = splhi(); p = dequeueproc(rq, p); if(p) queueproc(&runq[npri], p); splx(x); goto another; } } } /* * pick a process to run */ Proc* runproc(void) { Schedq *rq; Proc *p; ulong start, now; int i; void (*pt)(Proc*, int, vlong); start = perfticks(); /* cooperative scheduling until the clock ticks */ if(coopsched && (p=m->readied) && p->mach==0 && p->state==Ready && runq[Nrq-1].head == nil && runq[Nrq-2].head == nil){ skipscheds++; rq = &runq[p->priority]; goto found; } preempts++; loop: /* * find a process that last ran on this processor (affinity), * or one that hasn't moved in a while (load balancing). Every * time around the loop affinity goes down. */ spllo(); for(i = 0;; i++){ /* * find the highest priority target process that this * processor can run given affinity constraints. * */ for(rq = &runq[Nrq-1]; rq >= runq; rq--){ for(p = rq->head; p; p = p->rnext){ if(p->mp == nil || p->mp == MACHP(m->machno) || (!p->wired && i > 0)) goto found; } } /* waste time or halt the CPU */ idlehands(); /* remember how much time we're here */ now = perfticks(); m->perf.inidle += now-start; start = now; } found: splhi(); p = dequeueproc(rq, p); if(p == nil) goto loop; p->state = Scheding; p->mp = MACHP(m->machno); if(edflock(p)){ edfrun(p, rq == &runq[PriEdf]); /* start deadline timer and do admin */ edfunlock(); } pt = proctrace; if(pt) pt(p, SRun, 0); return p; } int canpage(Proc *p) { int ok = 0; splhi(); lock(runq); /* Only reliable way to see if we are Running */ if(p->mach == 0) { p->newtlb = 1; ok = 1; } unlock(runq); spllo(); return ok; } Proc* newproc(void) { Proc *p; lock(&procalloc); for(;;) { if(p = procalloc.free) break; unlock(&procalloc); resrcwait("no procs"); lock(&procalloc); } procalloc.free = p->qnext; unlock(&procalloc); p->state = Scheding; p->psstate = "New"; p->mach = 0; p->qnext = 0; p->nchild = 0; p->nwait = 0; p->waitq = 0; p->parent = 0; p->pgrp = 0; p->egrp = 0; p->fgrp = 0; p->rgrp = 0; p->pdbg = 0; p->fpstate = FPinit; p->kp = 0; p->procctl = 0; p->notepending = 0; p->ureg = 0; p->privatemem = 0; p->noswap = 0; p->errstr = p->errbuf0; p->syserrstr = p->errbuf1; p->errbuf0[0] = '\0'; p->errbuf1[0] = '\0'; p->nlocks.ref = 0; p->delaysched = 0; p->trace = 0; kstrdup(&p->user, "*nouser"); kstrdup(&p->text, "*notext"); kstrdup(&p->args, ""); p->nargs = 0; p->setargs = 0; memset(p->seg, 0, sizeof p->seg); p->pid = incref(&pidalloc); pidhash(p); p->noteid = incref(¬eidalloc); if(p->pid==0 || p->noteid==0) panic("pidalloc"); if(p->kstack == 0) p->kstack = smalloc(KSTACK); /* sched params */ p->mp = 0; p->wired = 0; procpriority(p, PriNormal, 0); p->cpu = 0; p->lastupdate = MACHP(0)->ticks*Scaling; p->edf = nil; return p; } /* * wire this proc to a machine */ void procwired(Proc *p, int bm) { Proc *pp; int i; char nwired[MAXMACH]; Mach *wm; if(bm < 0){ /* pick a machine to wire to */ memset(nwired, 0, sizeof(nwired)); p->wired = 0; pp = proctab(0); for(i=0; iwired; if(wm && pp->pid) nwired[wm->machno]++; } bm = 0; for(i=0; iwired = MACHP(bm); p->mp = p->wired; } void procpriority(Proc *p, int pri, int fixed) { if(pri >= Npriq) pri = Npriq - 1; else if(pri < 0) pri = 0; p->basepri = pri; p->priority = pri; if(fixed){ p->fixedpri = 1; } else { p->fixedpri = 0; } } void procinit0(void) /* bad planning - clashes with devproc.c */ { Proc *p; int i; procalloc.free = xalloc(conf.nproc*sizeof(Proc)); if(procalloc.free == nil){ xsummary(); panic("cannot allocate %lud procs (%ludMB)\n", conf.nproc, conf.nproc*sizeof(Proc)/(1024*1024)); } procalloc.arena = procalloc.free; p = procalloc.free; for(i=0; iqnext = p+1; p->qnext = 0; } /* * sleep if a condition is not true. Another process will * awaken us after it sets the condition. When we awaken * the condition may no longer be true. * * we lock both the process and the rendezvous to keep r->p * and p->r synchronized. */ void sleep(Rendez *r, int (*f)(void*), void *arg) { int s; void (*pt)(Proc*, int, vlong); s = splhi(); if(up->nlocks.ref) print("process %lud sleeps with %lud locks held, last lock 0x%p locked at pc 0x%lux, sleep called from 0x%lux\n", up->pid, up->nlocks.ref, up->lastlock, up->lastlock->pc, getcallerpc(&r)); lock(r); lock(&up->rlock); if(r->p){ print("double sleep called from 0x%lux, %lud %lud\n", getcallerpc(&r), r->p->pid, up->pid); dumpstack(); } /* * Wakeup only knows there may be something to do by testing * r->p in order to get something to lock on. * Flush that information out to memory in case the sleep is * committed. */ r->p = up; if((*f)(arg) || up->notepending){ /* * if condition happened or a note is pending * never mind */ r->p = nil; unlock(&up->rlock); unlock(r); } else { /* * now we are committed to * change state and call scheduler */ pt = proctrace; if(pt) pt(up, SSleep, 0); up->state = Wakeme; up->r = r; /* statistics */ m->cs++; procsave(up); if(setlabel(&up->sched)) { /* * here when the process is awakened */ procrestore(up); spllo(); } else { /* * here to go to sleep (i.e. stop Running) */ unlock(&up->rlock); unlock(r); gotolabel(&m->sched); } } if(up->notepending) { up->notepending = 0; splx(s); error(Eintr); } splx(s); } static int tfn(void *arg) { return up->trend == nil || up->tfn(arg); } void twakeup(Ureg*, Timer *t) { Proc *p; Rendez *trend; p = t->ta; trend = p->trend; p->trend = 0; if(trend) wakeup(trend); } /* Sleep until todget() >= ns. NOTE: ns is not an interval */ void tnsleep(Rendez *r, int (*fn)(void*), void *arg, vlong ns) { if (up->tt){ print("tnsleep: timer active: mode %d, tf 0x%lux\n", up->tmode, up->tf); timerdel(up); } up->tns = ns; up->tf = twakeup; up->tmode = Tabsolute; up->ta = up; up->trend = r; up->tfn = fn; timeradd(up); if(waserror()){ timerdel(up); nexterror(); } sleep(r, tfn, arg); if (up->tt) timerdel(up); up->twhen = 0; poperror(); } void tsleep(Rendez *r, int (*fn)(void*), void *arg, ulong ms) { if (up->tt){ print("tsleep: timer active: mode %d, tf 0x%lux\n", up->tmode, up->tf); timerdel(up); } up->tns = MS2NS(ms); up->tf = twakeup; up->tmode = Trelative; up->ta = up; up->trend = r; up->tfn = fn; timeradd(up); if(waserror()){ timerdel(up); nexterror(); } sleep(r, tfn, arg); if (up->tt) timerdel(up); up->twhen = 0; poperror(); } /* * Expects that only one process can call wakeup for any given Rendez. * We hold both locks to ensure that r->p and p->r remain consistent. * Richard Miller has a better solution that doesn't require both to * be held simultaneously, but I'm a paranoid - presotto. */ Proc* wakeup(Rendez *r) { Proc *p; int s; s = splhi(); lock(r); p = r->p; if(p != nil){ lock(&p->rlock); if(p->state != Wakeme || p->r != r) panic("wakeup: state"); r->p = nil; p->r = nil; ready(p); unlock(&p->rlock); } unlock(r); splx(s); return p; } /* * if waking a sleeping process, this routine must hold both * p->rlock and r->lock. However, it can't know them in * the same order as wakeup causing a possible lock ordering * deadlock. We break the deadlock by giving up the p->rlock * lock if we can't get the r->lock and retrying. */ int postnote(Proc *p, int dolock, char *n, int flag) { int s, ret; Rendez *r; Proc *d, **l; if(dolock) qlock(&p->debug); if(flag != NUser && (p->notify == 0 || p->notified)) p->nnote = 0; ret = 0; if(p->nnote < NNOTE) { strcpy(p->note[p->nnote].msg, n); p->note[p->nnote++].flag = flag; ret = 1; } p->notepending = 1; if(dolock) qunlock(&p->debug); /* this loop is to avoid lock ordering problems. */ for(;;){ s = splhi(); lock(&p->rlock); r = p->r; /* waiting for a wakeup? */ if(r == nil) break; /* no */ /* try for the second lock */ if(canlock(r)){ if(p->state != Wakeme || r->p != p) panic("postnote: state %d %d %d", r->p != p, p->r != r, p->state); p->r = nil; r->p = nil; ready(p); unlock(r); break; } /* give other process time to get out of critical section and try again */ unlock(&p->rlock); splx(s); sched(); } unlock(&p->rlock); splx(s); if(p->state != Rendezvous) return ret; /* Try and pull out of a rendezvous */ lock(p->rgrp); if(p->state == Rendezvous) { p->rendval = ~0; l = &REND(p->rgrp, p->rendtag); for(d = *l; d; d = d->rendhash) { if(d == p) { *l = p->rendhash; break; } l = &d->rendhash; } ready(p); } unlock(p->rgrp); return ret; } /* * weird thing: keep at most NBROKEN around */ #define NBROKEN 4 struct { QLock; int n; Proc *p[NBROKEN]; }broken; void addbroken(Proc *p) { qlock(&broken); if(broken.n == NBROKEN) { ready(broken.p[0]); memmove(&broken.p[0], &broken.p[1], sizeof(Proc*)*(NBROKEN-1)); --broken.n; } broken.p[broken.n++] = p; qunlock(&broken); edfstop(up); p->state = Broken; p->psstate = 0; sched(); } void unbreak(Proc *p) { int b; qlock(&broken); for(b=0; b < broken.n; b++) if(broken.p[b] == p) { broken.n--; memmove(&broken.p[b], &broken.p[b+1], sizeof(Proc*)*(NBROKEN-(b+1))); ready(p); break; } qunlock(&broken); } int freebroken(void) { int i, n; qlock(&broken); n = broken.n; for(i=0; ialarm = 0; if (up->tt) timerdel(up); pt = proctrace; if(pt) pt(up, SDead, 0); /* nil out all the resources under lock (free later) */ qlock(&up->debug); fgrp = up->fgrp; up->fgrp = nil; egrp = up->egrp; up->egrp = nil; rgrp = up->rgrp; up->rgrp = nil; pgrp = up->pgrp; up->pgrp = nil; dot = up->dot; up->dot = nil; qunlock(&up->debug); if(fgrp) closefgrp(fgrp); if(egrp) closeegrp(egrp); if(rgrp) closergrp(rgrp); if(dot) cclose(dot); if(pgrp) closepgrp(pgrp); /* * if not a kernel process and have a parent, * do some housekeeping. */ if(up->kp == 0) { p = up->parent; if(p == 0) { if(exitstr == 0) exitstr = "unknown"; panic("boot process died: %s", exitstr); } while(waserror()) ; wq = smalloc(sizeof(Waitq)); poperror(); wq->w.pid = up->pid; utime = up->time[TUser] + up->time[TCUser]; stime = up->time[TSys] + up->time[TCSys]; wq->w.time[TUser] = tk2ms(utime); wq->w.time[TSys] = tk2ms(stime); wq->w.time[TReal] = tk2ms(MACHP(0)->ticks - up->time[TReal]); if(exitstr && exitstr[0]) snprint(wq->w.msg, sizeof(wq->w.msg), "%s %lud: %s", up->text, up->pid, exitstr); else wq->w.msg[0] = '\0'; lock(&p->exl); /* * If my parent is no longer alive, or if there would be more * than 128 zombie child processes for my parent, then don't * leave a wait record behind. This helps prevent badly * written daemon processes from accumulating lots of wait * records. */ if(p->pid == up->parentpid && p->state != Broken && p->nwait < 128) { p->nchild--; p->time[TCUser] += utime; p->time[TCSys] += stime; wq->next = p->waitq; p->waitq = wq; p->nwait++; wakeup(&p->waitr); unlock(&p->exl); } else { unlock(&p->exl); free(wq); } } if(!freemem) addbroken(up); qlock(&up->seglock); es = &up->seg[NSEG]; for(s = up->seg; s < es; s++) { if(*s) { putseg(*s); *s = 0; } } qunlock(&up->seglock); lock(&up->exl); /* Prevent my children from leaving waits */ pidunhash(up); up->pid = 0; wakeup(&up->waitr); unlock(&up->exl); for(f = up->waitq; f; f = next) { next = f->next; free(f); } /* release debuggers */ qlock(&up->debug); if(up->pdbg) { wakeup(&up->pdbg->sleep); up->pdbg = 0; } qunlock(&up->debug); /* Sched must not loop for these locks */ lock(&procalloc); lock(&palloc); edfstop(up); up->state = Moribund; sched(); panic("pexit"); } int haswaitq(void *x) { Proc *p; p = (Proc *)x; return p->waitq != 0; } ulong pwait(Waitmsg *w) { ulong cpid; Waitq *wq; if(!canqlock(&up->qwaitr)) error(Einuse); if(waserror()) { qunlock(&up->qwaitr); nexterror(); } lock(&up->exl); if(up->nchild == 0 && up->waitq == 0) { unlock(&up->exl); error(Enochild); } unlock(&up->exl); sleep(&up->waitr, haswaitq, up); lock(&up->exl); wq = up->waitq; up->waitq = wq->next; up->nwait--; unlock(&up->exl); qunlock(&up->qwaitr); poperror(); if(w) memmove(w, &wq->w, sizeof(Waitmsg)); cpid = wq->w.pid; free(wq); return cpid; } Proc* proctab(int i) { return &procalloc.arena[i]; } void dumpaproc(Proc *p) { ulong bss; char *s; if(p == 0) return; bss = 0; if(p->seg[BSEG]) bss = p->seg[BSEG]->top; s = p->psstate; if(s == 0) s = statename[p->state]; print("%3lud:%10s pc %8lux dbgpc %8lux %8s (%s) ut %ld st %ld bss %lux qpc %lux nl %lud nd %lud lpc %lux pri %lud\n", p->pid, p->text, p->pc, dbgpc(p), s, statename[p->state], p->time[0], p->time[1], bss, p->qpc, p->nlocks.ref, p->delaysched, p->lastlock ? p->lastlock->pc : 0, p->priority); } void procdump(void) { int i; Proc *p; if(up) print("up %lud\n", up->pid); else print("no current process\n"); for(i=0; istate == Dead) continue; dumpaproc(p); } } /* * wait till all processes have flushed their mmu * state about segement s */ void procflushseg(Segment *s) { int i, ns, nm, nwait; Proc *p; /* * tell all processes with this * segment to flush their mmu's */ nwait = 0; for(i=0; istate == Dead) continue; for(ns = 0; ns < NSEG; ns++) if(p->seg[ns] == s){ p->newtlb = 1; for(nm = 0; nm < conf.nmach; nm++){ if(MACHP(nm)->proc == p){ MACHP(nm)->flushmmu = 1; nwait++; } } break; } } if(nwait == 0) return; /* * wait for all processors to take a clock interrupt * and flush their mmu's */ for(nm = 0; nm < conf.nmach; nm++) if(MACHP(nm) != m) while(MACHP(nm)->flushmmu) sched(); } void scheddump(void) { Proc *p; Schedq *rq; for(rq = &runq[Nrq-1]; rq >= runq; rq--){ if(rq->head == 0) continue; print("rq%ld:", rq-runq); for(p = rq->head; p; p = p->rnext) print(" %lud(%lud)", p->pid, m->ticks - p->readytime); print("\n"); delay(150); } print("nrdy %d\n", nrdy); } void kproc(char *name, void (*func)(void *), void *arg) { Proc *p; static Pgrp *kpgrp; p = newproc(); p->psstate = 0; p->procmode = 0640; p->kp = 1; p->noswap = 1; p->fpsave = up->fpsave; p->scallnr = up->scallnr; p->s = up->s; p->nerrlab = 0; p->slash = up->slash; p->dot = up->dot; incref(p->dot); memmove(p->note, up->note, sizeof(p->note)); p->nnote = up->nnote; p->notified = 0; p->lastnote = up->lastnote; p->notify = up->notify; p->ureg = 0; p->dbgreg = 0; procpriority(p, PriKproc, 0); kprocchild(p, func, arg); kstrdup(&p->user, eve); kstrdup(&p->text, name); if(kpgrp == 0) kpgrp = newpgrp(); p->pgrp = kpgrp; incref(kpgrp); memset(p->time, 0, sizeof(p->time)); p->time[TReal] = MACHP(0)->ticks; ready(p); /* * since the bss/data segments are now shareable, * any mmu info about this process is now stale * and has to be discarded. */ p->newtlb = 1; flushmmu(); } /* * called splhi() by notify(). See comment in notify for the * reasoning. */ void procctl(Proc *p) { char *state; ulong s; switch(p->procctl) { case Proc_exitbig: spllo(); pexit("Killed: Insufficient physical memory", 1); case Proc_exitme: spllo(); /* pexit has locks in it */ pexit("Killed", 1); case Proc_traceme: if(p->nnote == 0) return; /* No break */ case Proc_stopme: p->procctl = 0; state = p->psstate; p->psstate = "Stopped"; /* free a waiting debugger */ s = spllo(); qlock(&p->debug); if(p->pdbg) { wakeup(&p->pdbg->sleep); p->pdbg = 0; } qunlock(&p->debug); splhi(); p->state = Stopped; sched(); p->psstate = state; splx(s); return; } } #include "errstr.h" void error(char *err) { spllo(); assert(up->nerrlab < NERR); kstrcpy(up->errstr, err, ERRMAX); setlabel(&up->errlab[NERR-1]); nexterror(); } void nexterror(void) { gotolabel(&up->errlab[--up->nerrlab]); } void exhausted(char *resource) { char buf[ERRMAX]; sprint(buf, "no free %s", resource); iprint("%s\n", buf); error(buf); } void killbig(void) { int i; Segment *s; ulong l, max; Proc *p, *ep, *kp; max = 0; kp = 0; ep = procalloc.arena+conf.nproc; for(p = procalloc.arena; p < ep; p++) { if(p->state == Dead || p->kp) continue; l = 0; for(i=1; iseg[i]; if(s != 0) l += s->top - s->base; } if(l > max && strcmp(p->text, "kfs") != 0 && strcmp(p->text, "fossil") != 0 && strcmp(p->text, "venti") != 0) { kp = p; max = l; } } kp->procctl = Proc_exitbig; for(i = 0; i < NSEG; i++) { s = kp->seg[i]; if(s != 0 && canqlock(&s->lk)) { mfreeseg(s, s->base, (s->top - s->base)/BY2PG); qunlock(&s->lk); } } print("%lud: %s killed by killbig()\n", kp->pid, kp->text); } /* * change ownership to 'new' of all processes owned by 'old'. Used when * eve changes. */ void renameuser(char *old, char *new) { Proc *p, *ep; ep = procalloc.arena+conf.nproc; for(p = procalloc.arena; p < ep; p++) if(p->user!=nil && strcmp(old, p->user)==0) kstrdup(&p->user, new); } /* * time accounting called by clock() splhi'd */ void accounttime(void) { Proc *p; ulong n, per; static ulong nrun; p = m->proc; if(p) { nrun++; p->time[p->insyscall]++; } /* calculate decaying duty cycles */ n = perfticks(); per = n - m->perf.last; m->perf.last = n; per = (m->perf.period*(HZ-1) + per)/HZ; if(per != 0) m->perf.period = per; m->perf.avg_inidle = (m->perf.avg_inidle*(HZ-1)+m->perf.inidle)/HZ; m->perf.inidle = 0; m->perf.avg_inintr = (m->perf.avg_inintr*(HZ-1)+m->perf.inintr)/HZ; m->perf.inintr = 0; /* only one processor gets to compute system load averages */ if(m->machno != 0) return; /* * calculate decaying load average. * if we decay by (n-1)/n then it takes * n clock ticks to go from load L to .36 L once * things quiet down. it takes about 5 n clock * ticks to go to zero. so using HZ means this is * approximately the load over the last second, * with a tail lasting about 5 seconds. */ n = nrun; nrun = 0; n = (nrdy+n)*1000; m->load = (m->load*(HZ-1)+n)/HZ; } static void pidhash(Proc *p) { int h; h = p->pid % nelem(procalloc.ht); lock(&procalloc); p->pidhash = procalloc.ht[h]; procalloc.ht[h] = p; unlock(&procalloc); } static void pidunhash(Proc *p) { int h; Proc **l; h = p->pid % nelem(procalloc.ht); lock(&procalloc); for(l = &procalloc.ht[h]; *l != nil; l = &(*l)->pidhash) if(*l == p){ *l = p->pidhash; break; } unlock(&procalloc); } int procindex(ulong pid) { Proc *p; int h; int s; s = -1; h = pid % nelem(procalloc.ht); lock(&procalloc); for(p = procalloc.ht[h]; p != nil; p = p->pidhash) if(p->pid == pid){ s = p - procalloc.arena; break; } unlock(&procalloc); return s; }