kern_synch.c revision 1.43 1 /* $NetBSD: kern_synch.c,v 1.43 1996/11/06 20:20:00 cgd Exp $ */
2
3 /*-
4 * Copyright (c) 1982, 1986, 1990, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the University of
23 * California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 * @(#)kern_synch.c 8.6 (Berkeley) 1/21/94
41 */
42
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/proc.h>
46 #include <sys/kernel.h>
47 #include <sys/buf.h>
48 #include <sys/signalvar.h>
49 #include <sys/resourcevar.h>
50 #include <vm/vm.h>
51 #ifdef KTRACE
52 #include <sys/ktrace.h>
53 #endif
54
55 #include <machine/cpu.h>
56
57 u_char curpriority; /* usrpri of curproc */
58 int lbolt; /* once a second sleep address */
59
60 void roundrobin __P((void *));
61 void schedcpu __P((void *));
62 void updatepri __P((struct proc *));
63 void endtsleep __P((void *));
64
65 /*
66 * Force switch among equal priority processes every 100ms.
67 */
68 /* ARGSUSED */
69 void
70 roundrobin(arg)
71 void *arg;
72 {
73
74 need_resched();
75 timeout(roundrobin, NULL, hz / 10);
76 }
77
78 /*
79 * Constants for digital decay and forget:
80 * 90% of (p_estcpu) usage in 5 * loadav time
81 * 95% of (p_pctcpu) usage in 60 seconds (load insensitive)
82 * Note that, as ps(1) mentions, this can let percentages
83 * total over 100% (I've seen 137.9% for 3 processes).
84 *
85 * Note that hardclock updates p_estcpu and p_cpticks independently.
86 *
87 * We wish to decay away 90% of p_estcpu in (5 * loadavg) seconds.
88 * That is, the system wants to compute a value of decay such
89 * that the following for loop:
90 * for (i = 0; i < (5 * loadavg); i++)
91 * p_estcpu *= decay;
92 * will compute
93 * p_estcpu *= 0.1;
94 * for all values of loadavg:
95 *
96 * Mathematically this loop can be expressed by saying:
97 * decay ** (5 * loadavg) ~= .1
98 *
99 * The system computes decay as:
100 * decay = (2 * loadavg) / (2 * loadavg + 1)
101 *
102 * We wish to prove that the system's computation of decay
103 * will always fulfill the equation:
104 * decay ** (5 * loadavg) ~= .1
105 *
106 * If we compute b as:
107 * b = 2 * loadavg
108 * then
109 * decay = b / (b + 1)
110 *
111 * We now need to prove two things:
112 * 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1)
113 * 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg)
114 *
115 * Facts:
116 * For x close to zero, exp(x) =~ 1 + x, since
117 * exp(x) = 0! + x**1/1! + x**2/2! + ... .
118 * therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b.
119 * For x close to zero, ln(1+x) =~ x, since
120 * ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1
121 * therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1).
122 * ln(.1) =~ -2.30
123 *
124 * Proof of (1):
125 * Solve (factor)**(power) =~ .1 given power (5*loadav):
126 * solving for factor,
127 * ln(factor) =~ (-2.30/5*loadav), or
128 * factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) =
129 * exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED
130 *
131 * Proof of (2):
132 * Solve (factor)**(power) =~ .1 given factor == (b/(b+1)):
133 * solving for power,
134 * power*ln(b/(b+1)) =~ -2.30, or
135 * power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED
136 *
137 * Actual power values for the implemented algorithm are as follows:
138 * loadav: 1 2 3 4
139 * power: 5.68 10.32 14.94 19.55
140 */
141
142 /* calculations for digital decay to forget 90% of usage in 5*loadav sec */
143 #define loadfactor(loadav) (2 * (loadav))
144 #define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE))
145
146 /* decay 95% of `p_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */
147 fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */
148
149 /*
150 * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the
151 * faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below
152 * and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT).
153 *
154 * To estimate CCPU_SHIFT for exp(-1/20), the following formula was used:
155 * 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits).
156 *
157 * If you dont want to bother with the faster/more-accurate formula, you
158 * can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate
159 * (more general) method of calculating the %age of CPU used by a process.
160 */
161 #define CCPU_SHIFT 11
162
163 /*
164 * Recompute process priorities, every hz ticks.
165 */
166 /* ARGSUSED */
167 void
168 schedcpu(arg)
169 void *arg;
170 {
171 register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
172 register struct proc *p;
173 register int s;
174 register unsigned int newcpu;
175
176 wakeup((caddr_t)&lbolt);
177 for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) {
178 /*
179 * Increment time in/out of memory and sleep time
180 * (if sleeping). We ignore overflow; with 16-bit int's
181 * (remember them?) overflow takes 45 days.
182 */
183 p->p_swtime++;
184 if (p->p_stat == SSLEEP || p->p_stat == SSTOP)
185 p->p_slptime++;
186 p->p_pctcpu = (p->p_pctcpu * ccpu) >> FSHIFT;
187 /*
188 * If the process has slept the entire second,
189 * stop recalculating its priority until it wakes up.
190 */
191 if (p->p_slptime > 1)
192 continue;
193 s = splstatclock(); /* prevent state changes */
194 /*
195 * p_pctcpu is only for ps.
196 */
197 #if (FSHIFT >= CCPU_SHIFT)
198 p->p_pctcpu += (hz == 100)?
199 ((fixpt_t) p->p_cpticks) << (FSHIFT - CCPU_SHIFT):
200 100 * (((fixpt_t) p->p_cpticks)
201 << (FSHIFT - CCPU_SHIFT)) / hz;
202 #else
203 p->p_pctcpu += ((FSCALE - ccpu) *
204 (p->p_cpticks * FSCALE / hz)) >> FSHIFT;
205 #endif
206 p->p_cpticks = 0;
207 newcpu = (u_int)decay_cpu(loadfac, p->p_estcpu)
208 + p->p_nice - NZERO;
209 p->p_estcpu = min(newcpu, UCHAR_MAX);
210 resetpriority(p);
211 if (p->p_priority >= PUSER) {
212 #define PPQ (128 / NQS) /* priorities per queue */
213 if ((p != curproc) &&
214 p->p_stat == SRUN &&
215 (p->p_flag & P_INMEM) &&
216 (p->p_priority / PPQ) != (p->p_usrpri / PPQ)) {
217 remrunqueue(p);
218 p->p_priority = p->p_usrpri;
219 setrunqueue(p);
220 } else
221 p->p_priority = p->p_usrpri;
222 }
223 splx(s);
224 }
225 vmmeter();
226 if (bclnlist != NULL)
227 wakeup((caddr_t)pageproc);
228 timeout(schedcpu, (void *)0, hz);
229 }
230
231 /*
232 * Recalculate the priority of a process after it has slept for a while.
233 * For all load averages >= 1 and max p_estcpu of 255, sleeping for at
234 * least six times the loadfactor will decay p_estcpu to zero.
235 */
236 void
237 updatepri(p)
238 register struct proc *p;
239 {
240 register unsigned int newcpu = p->p_estcpu;
241 register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
242
243 if (p->p_slptime > 5 * loadfac)
244 p->p_estcpu = 0;
245 else {
246 p->p_slptime--; /* the first time was done in schedcpu */
247 while (newcpu && --p->p_slptime)
248 newcpu = (int) decay_cpu(loadfac, newcpu);
249 p->p_estcpu = min(newcpu, UCHAR_MAX);
250 }
251 resetpriority(p);
252 }
253
254 /*
255 * We're only looking at 7 bits of the address; everything is
256 * aligned to 4, lots of things are aligned to greater powers
257 * of 2. Shift right by 8, i.e. drop the bottom 256 worth.
258 */
259 #define TABLESIZE 128
260 #define LOOKUP(x) (((long)(x) >> 8) & (TABLESIZE - 1))
261 struct slpque {
262 struct proc *sq_head;
263 struct proc **sq_tailp;
264 } slpque[TABLESIZE];
265
266 /*
267 * During autoconfiguration or after a panic, a sleep will simply
268 * lower the priority briefly to allow interrupts, then return.
269 * The priority to be used (safepri) is machine-dependent, thus this
270 * value is initialized and maintained in the machine-dependent layers.
271 * This priority will typically be 0, or the lowest priority
272 * that is safe for use on the interrupt stack; it can be made
273 * higher to block network software interrupts after panics.
274 */
275 int safepri;
276
277 /*
278 * General sleep call. Suspends the current process until a wakeup is
279 * performed on the specified identifier. The process will then be made
280 * runnable with the specified priority. Sleeps at most timo/hz seconds
281 * (0 means no timeout). If pri includes PCATCH flag, signals are checked
282 * before and after sleeping, else signals are not checked. Returns 0 if
283 * awakened, EWOULDBLOCK if the timeout expires. If PCATCH is set and a
284 * signal needs to be delivered, ERESTART is returned if the current system
285 * call should be restarted if possible, and EINTR is returned if the system
286 * call should be interrupted by the signal (return EINTR).
287 */
288 int
289 tsleep(ident, priority, wmesg, timo)
290 void *ident;
291 int priority, timo;
292 char *wmesg;
293 {
294 register struct proc *p = curproc;
295 register struct slpque *qp;
296 register s;
297 int sig, catch = priority & PCATCH;
298 extern int cold;
299 void endtsleep __P((void *));
300
301 if (cold || panicstr) {
302 /*
303 * After a panic, or during autoconfiguration,
304 * just give interrupts a chance, then just return;
305 * don't run any other procs or panic below,
306 * in case this is the idle process and already asleep.
307 */
308 s = splhigh();
309 splx(safepri);
310 splx(s);
311 return (0);
312 }
313
314 #ifdef KTRACE
315 if (KTRPOINT(p, KTR_CSW))
316 ktrcsw(p->p_tracep, 1, 0);
317 #endif
318 s = splhigh();
319
320 #ifdef DIAGNOSTIC
321 if (ident == NULL || p->p_stat != SRUN || p->p_back)
322 panic("tsleep");
323 #endif
324 p->p_wchan = ident;
325 p->p_wmesg = wmesg;
326 p->p_slptime = 0;
327 p->p_priority = priority & PRIMASK;
328 qp = &slpque[LOOKUP(ident)];
329 if (qp->sq_head == 0)
330 qp->sq_head = p;
331 else
332 *qp->sq_tailp = p;
333 *(qp->sq_tailp = &p->p_forw) = 0;
334 if (timo)
335 timeout(endtsleep, (void *)p, timo);
336 /*
337 * We put ourselves on the sleep queue and start our timeout
338 * before calling CURSIG, as we could stop there, and a wakeup
339 * or a SIGCONT (or both) could occur while we were stopped.
340 * A SIGCONT would cause us to be marked as SSLEEP
341 * without resuming us, thus we must be ready for sleep
342 * when CURSIG is called. If the wakeup happens while we're
343 * stopped, p->p_wchan will be 0 upon return from CURSIG.
344 */
345 if (catch) {
346 p->p_flag |= P_SINTR;
347 if ((sig = CURSIG(p)) != 0) {
348 if (p->p_wchan)
349 unsleep(p);
350 p->p_stat = SRUN;
351 goto resume;
352 }
353 if (p->p_wchan == 0) {
354 catch = 0;
355 goto resume;
356 }
357 } else
358 sig = 0;
359 p->p_stat = SSLEEP;
360 p->p_stats->p_ru.ru_nvcsw++;
361 mi_switch();
362 #ifdef DDB
363 /* handy breakpoint location after process "wakes" */
364 asm(".globl bpendtsleep ; bpendtsleep:");
365 #endif
366 resume:
367 curpriority = p->p_usrpri;
368 splx(s);
369 p->p_flag &= ~P_SINTR;
370 if (p->p_flag & P_TIMEOUT) {
371 p->p_flag &= ~P_TIMEOUT;
372 if (sig == 0) {
373 #ifdef KTRACE
374 if (KTRPOINT(p, KTR_CSW))
375 ktrcsw(p->p_tracep, 0, 0);
376 #endif
377 return (EWOULDBLOCK);
378 }
379 } else if (timo)
380 untimeout(endtsleep, (void *)p);
381 if (catch && (sig != 0 || (sig = CURSIG(p)) != 0)) {
382 #ifdef KTRACE
383 if (KTRPOINT(p, KTR_CSW))
384 ktrcsw(p->p_tracep, 0, 0);
385 #endif
386 if (p->p_sigacts->ps_sigintr & sigmask(sig))
387 return (EINTR);
388 return (ERESTART);
389 }
390 #ifdef KTRACE
391 if (KTRPOINT(p, KTR_CSW))
392 ktrcsw(p->p_tracep, 0, 0);
393 #endif
394 return (0);
395 }
396
397 /*
398 * Implement timeout for tsleep.
399 * If process hasn't been awakened (wchan non-zero),
400 * set timeout flag and undo the sleep. If proc
401 * is stopped, just unsleep so it will remain stopped.
402 */
403 void
404 endtsleep(arg)
405 void *arg;
406 {
407 register struct proc *p;
408 int s;
409
410 p = (struct proc *)arg;
411 s = splhigh();
412 if (p->p_wchan) {
413 if (p->p_stat == SSLEEP)
414 setrunnable(p);
415 else
416 unsleep(p);
417 p->p_flag |= P_TIMEOUT;
418 }
419 splx(s);
420 }
421
422 /*
423 * Short-term, non-interruptable sleep.
424 */
425 void
426 sleep(ident, priority)
427 void *ident;
428 int priority;
429 {
430 register struct proc *p = curproc;
431 register struct slpque *qp;
432 register s;
433 extern int cold;
434
435 #ifdef DIAGNOSTIC
436 if (priority > PZERO) {
437 printf("sleep called with priority %d > PZERO, wchan: %p\n",
438 priority, ident);
439 panic("old sleep");
440 }
441 #endif
442 s = splhigh();
443 if (cold || panicstr) {
444 /*
445 * After a panic, or during autoconfiguration,
446 * just give interrupts a chance, then just return;
447 * don't run any other procs or panic below,
448 * in case this is the idle process and already asleep.
449 */
450 splx(safepri);
451 splx(s);
452 return;
453 }
454 #ifdef DIAGNOSTIC
455 if (ident == NULL || p->p_stat != SRUN || p->p_back)
456 panic("sleep");
457 #endif
458 p->p_wchan = ident;
459 p->p_wmesg = NULL;
460 p->p_slptime = 0;
461 p->p_priority = priority;
462 qp = &slpque[LOOKUP(ident)];
463 if (qp->sq_head == 0)
464 qp->sq_head = p;
465 else
466 *qp->sq_tailp = p;
467 *(qp->sq_tailp = &p->p_forw) = 0;
468 p->p_stat = SSLEEP;
469 p->p_stats->p_ru.ru_nvcsw++;
470 #ifdef KTRACE
471 if (KTRPOINT(p, KTR_CSW))
472 ktrcsw(p->p_tracep, 1, 0);
473 #endif
474 mi_switch();
475 #ifdef DDB
476 /* handy breakpoint location after process "wakes" */
477 asm(".globl bpendsleep ; bpendsleep:");
478 #endif
479 #ifdef KTRACE
480 if (KTRPOINT(p, KTR_CSW))
481 ktrcsw(p->p_tracep, 0, 0);
482 #endif
483 curpriority = p->p_usrpri;
484 splx(s);
485 }
486
487 /*
488 * Remove a process from its wait queue
489 */
490 void
491 unsleep(p)
492 register struct proc *p;
493 {
494 register struct slpque *qp;
495 register struct proc **hp;
496 int s;
497
498 s = splhigh();
499 if (p->p_wchan) {
500 hp = &(qp = &slpque[LOOKUP(p->p_wchan)])->sq_head;
501 while (*hp != p)
502 hp = &(*hp)->p_forw;
503 *hp = p->p_forw;
504 if (qp->sq_tailp == &p->p_forw)
505 qp->sq_tailp = hp;
506 p->p_wchan = 0;
507 }
508 splx(s);
509 }
510
511 /*
512 * Make all processes sleeping on the specified identifier runnable.
513 */
514 void
515 wakeup(ident)
516 register void *ident;
517 {
518 register struct slpque *qp;
519 register struct proc *p, **q;
520 int s;
521
522 s = splhigh();
523 qp = &slpque[LOOKUP(ident)];
524 restart:
525 for (q = &qp->sq_head; (p = *q) != NULL; ) {
526 #ifdef DIAGNOSTIC
527 if (p->p_back || (p->p_stat != SSLEEP && p->p_stat != SSTOP))
528 panic("wakeup");
529 #endif
530 if (p->p_wchan == ident) {
531 p->p_wchan = 0;
532 *q = p->p_forw;
533 if (qp->sq_tailp == &p->p_forw)
534 qp->sq_tailp = q;
535 if (p->p_stat == SSLEEP) {
536 /* OPTIMIZED EXPANSION OF setrunnable(p); */
537 if (p->p_slptime > 1)
538 updatepri(p);
539 p->p_slptime = 0;
540 p->p_stat = SRUN;
541 if (p->p_flag & P_INMEM)
542 setrunqueue(p);
543 /*
544 * Since curpriority is a user priority,
545 * p->p_priority is always better than
546 * curpriority.
547 */
548 if ((p->p_flag & P_INMEM) == 0)
549 wakeup((caddr_t)&proc0);
550 else
551 need_resched();
552 /* END INLINE EXPANSION */
553 goto restart;
554 }
555 } else
556 q = &p->p_forw;
557 }
558 splx(s);
559 }
560
561 /*
562 * The machine independent parts of mi_switch().
563 * Must be called at splstatclock() or higher.
564 */
565 void
566 mi_switch()
567 {
568 register struct proc *p = curproc; /* XXX */
569 register struct rlimit *rlim;
570 register long s, u;
571 struct timeval tv;
572
573 /*
574 * Compute the amount of time during which the current
575 * process was running, and add that to its total so far.
576 */
577 microtime(&tv);
578 u = p->p_rtime.tv_usec + (tv.tv_usec - runtime.tv_usec);
579 s = p->p_rtime.tv_sec + (tv.tv_sec - runtime.tv_sec);
580 if (u < 0) {
581 u += 1000000;
582 s--;
583 } else if (u >= 1000000) {
584 u -= 1000000;
585 s++;
586 }
587 p->p_rtime.tv_usec = u;
588 p->p_rtime.tv_sec = s;
589
590 /*
591 * Check if the process exceeds its cpu resource allocation.
592 * If over max, kill it. In any case, if it has run for more
593 * than 10 minutes, reduce priority to give others a chance.
594 */
595 rlim = &p->p_rlimit[RLIMIT_CPU];
596 if (s >= rlim->rlim_cur) {
597 if (s >= rlim->rlim_max)
598 psignal(p, SIGKILL);
599 else {
600 psignal(p, SIGXCPU);
601 if (rlim->rlim_cur < rlim->rlim_max)
602 rlim->rlim_cur += 5;
603 }
604 }
605 if (autonicetime && s > autonicetime && p->p_ucred->cr_uid && p->p_nice == NZERO) {
606 p->p_nice = autoniceval + NZERO;
607 resetpriority(p);
608 }
609
610 /*
611 * Pick a new current process and record its start time.
612 */
613 cnt.v_swtch++;
614 cpu_switch(p);
615 microtime(&runtime);
616 }
617
618 /*
619 * Initialize the (doubly-linked) run queues
620 * to be empty.
621 */
622 void
623 rqinit()
624 {
625 register int i;
626
627 for (i = 0; i < NQS; i++)
628 qs[i].ph_link = qs[i].ph_rlink = (struct proc *)&qs[i];
629 }
630
631 /*
632 * Change process state to be runnable,
633 * placing it on the run queue if it is in memory,
634 * and awakening the swapper if it isn't in memory.
635 */
636 void
637 setrunnable(p)
638 register struct proc *p;
639 {
640 register int s;
641
642 s = splhigh();
643 switch (p->p_stat) {
644 case 0:
645 case SRUN:
646 case SZOMB:
647 default:
648 panic("setrunnable");
649 case SSTOP:
650 /*
651 * If we're being traced (possibly because someone attached us
652 * while we were stopped), check for a signal from the debugger.
653 */
654 if ((p->p_flag & P_TRACED) != 0 && p->p_xstat != 0)
655 p->p_siglist |= sigmask(p->p_xstat);
656 case SSLEEP:
657 unsleep(p); /* e.g. when sending signals */
658 break;
659
660 case SIDL:
661 break;
662 }
663 p->p_stat = SRUN;
664 if (p->p_flag & P_INMEM)
665 setrunqueue(p);
666 splx(s);
667 if (p->p_slptime > 1)
668 updatepri(p);
669 p->p_slptime = 0;
670 if ((p->p_flag & P_INMEM) == 0)
671 wakeup((caddr_t)&proc0);
672 else if (p->p_priority < curpriority)
673 need_resched();
674 }
675
676 /*
677 * Compute the priority of a process when running in user mode.
678 * Arrange to reschedule if the resulting priority is better
679 * than that of the current process.
680 */
681 void
682 resetpriority(p)
683 register struct proc *p;
684 {
685 register unsigned int newpriority;
686
687 newpriority = PUSER + p->p_estcpu / 4 + 2 * (p->p_nice - NZERO);
688 newpriority = min(newpriority, MAXPRI);
689 p->p_usrpri = newpriority;
690 if (newpriority < curpriority)
691 need_resched();
692 }
693
694 #ifdef DDB
695 #include <machine/db_machdep.h>
696
697 #include <ddb/db_interface.h>
698 #include <ddb/db_output.h>
699
700 void
701 db_show_all_procs(addr, haddr, count, modif)
702 db_expr_t addr;
703 int haddr;
704 db_expr_t count;
705 char *modif;
706 {
707 int map = modif[0] == 'm';
708 int doingzomb = 0;
709 struct proc *p, *pp;
710
711 p = allproc.lh_first;
712 db_printf(" pid proc addr %s comm wchan\n",
713 map ? "map " : "uid ppid pgrp flag stat em ");
714 while (p != 0) {
715 pp = p->p_pptr;
716 if (p->p_stat) {
717 db_printf("%5d %p %p ",
718 p->p_pid, p, p->p_addr);
719 if (map)
720 db_printf("%p %s ",
721 p->p_vmspace, p->p_comm);
722 else
723 db_printf("%3d %5d %5d %06x %d %s %s ",
724 p->p_cred->p_ruid, pp ? pp->p_pid : -1,
725 p->p_pgrp->pg_id, p->p_flag, p->p_stat,
726 p->p_emul->e_name, p->p_comm);
727 if (p->p_wchan) {
728 if (p->p_wmesg)
729 db_printf("%s ", p->p_wmesg);
730 db_printf("%p", p->p_wchan);
731 }
732 db_printf("\n");
733 }
734 p = p->p_list.le_next;
735 if (p == 0 && doingzomb == 0) {
736 doingzomb = 1;
737 p = zombproc.lh_first;
738 }
739 }
740 }
741 #endif
742