1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 * Copyright 2013 Joyent, Inc. All rights reserved.
26 */
27
28 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
29 /* All Rights Reserved */
30
31 #include <sys/types.h>
32 #include <sys/param.h>
33 #include <sys/sysmacros.h>
34 #include <sys/cred.h>
35 #include <sys/proc.h>
36 #include <sys/pcb.h>
37 #include <sys/signal.h>
38 #include <sys/user.h>
39 #include <sys/priocntl.h>
40 #include <sys/class.h>
41 #include <sys/disp.h>
42 #include <sys/procset.h>
43 #include <sys/cmn_err.h>
44 #include <sys/debug.h>
45 #include <sys/rt.h>
46 #include <sys/rtpriocntl.h>
47 #include <sys/kmem.h>
48 #include <sys/systm.h>
49 #include <sys/schedctl.h>
50 #include <sys/errno.h>
51 #include <sys/cpuvar.h>
52 #include <sys/vmsystm.h>
53 #include <sys/time.h>
54 #include <sys/policy.h>
55 #include <sys/sdt.h>
56 #include <sys/cpupart.h>
57 #include <sys/modctl.h>
58
59 static pri_t rt_init(id_t, int, classfuncs_t **);
60
61 static struct sclass csw = {
62 "RT",
63 rt_init,
64 0
65 };
66
67 static struct modlsched modlsched = {
68 &mod_schedops, "realtime scheduling class", &csw
69 };
70
71 static struct modlinkage modlinkage = {
72 MODREV_1, (void *)&modlsched, NULL
73 };
74
75 int
_init()76 _init()
77 {
78 return (mod_install(&modlinkage));
79 }
80
81 int
_fini()82 _fini()
83 {
84 return (EBUSY); /* don't remove RT for now */
85 }
86
87 int
_info(struct modinfo * modinfop)88 _info(struct modinfo *modinfop)
89 {
90 return (mod_info(&modlinkage, modinfop));
91 }
92
93
94 /*
95 * Class specific code for the real-time class
96 */
97
98 /*
99 * Extern declarations for variables defined in the rt master file
100 */
101 #define RTMAXPRI 59
102
103 pri_t rt_maxpri = RTMAXPRI; /* maximum real-time priority */
104 rtdpent_t *rt_dptbl; /* real-time dispatcher parameter table */
105
106 /*
107 * control flags (kparms->rt_cflags).
108 */
109 #define RT_DOPRI 0x01 /* change priority */
110 #define RT_DOTQ 0x02 /* change RT time quantum */
111 #define RT_DOSIG 0x04 /* change RT time quantum signal */
112
113 static int rt_admin(caddr_t, cred_t *);
114 static int rt_enterclass(kthread_t *, id_t, void *, cred_t *, void *);
115 static int rt_fork(kthread_t *, kthread_t *, void *);
116 static int rt_getclinfo(void *);
117 static int rt_getclpri(pcpri_t *);
118 static int rt_parmsin(void *);
119 static int rt_parmsout(void *, pc_vaparms_t *);
120 static int rt_vaparmsin(void *, pc_vaparms_t *);
121 static int rt_vaparmsout(void *, pc_vaparms_t *);
122 static int rt_parmsset(kthread_t *, void *, id_t, cred_t *);
123 static int rt_donice(kthread_t *, cred_t *, int, int *);
124 static int rt_doprio(kthread_t *, cred_t *, int, int *);
125 static void rt_exitclass(void *);
126 static int rt_canexit(kthread_t *, cred_t *);
127 static void rt_forkret(kthread_t *, kthread_t *);
128 static void rt_nullsys();
129 static void rt_parmsget(kthread_t *, void *);
130 static void rt_preempt(kthread_t *);
131 static void rt_setrun(kthread_t *);
132 static void rt_tick(kthread_t *);
133 static void rt_wakeup(kthread_t *);
134 static pri_t rt_swapin(kthread_t *, int);
135 static pri_t rt_swapout(kthread_t *, int);
136 static pri_t rt_globpri(kthread_t *);
137 static void rt_yield(kthread_t *);
138 static int rt_alloc(void **, int);
139 static void rt_free(void *);
140
141 static void rt_change_priority(kthread_t *, rtproc_t *);
142
143 static id_t rt_cid; /* real-time class ID */
144 static rtproc_t rt_plisthead; /* dummy rtproc at head of rtproc list */
145 static kmutex_t rt_dptblock; /* protects realtime dispatch table */
146 static kmutex_t rt_list_lock; /* protects RT thread list */
147
148 extern rtdpent_t *rt_getdptbl(void);
149
150 static struct classfuncs rt_classfuncs = {
151 /* class ops */
152 rt_admin,
153 rt_getclinfo,
154 rt_parmsin,
155 rt_parmsout,
156 rt_vaparmsin,
157 rt_vaparmsout,
158 rt_getclpri,
159 rt_alloc,
160 rt_free,
161 /* thread ops */
162 rt_enterclass,
163 rt_exitclass,
164 rt_canexit,
165 rt_fork,
166 rt_forkret,
167 rt_parmsget,
168 rt_parmsset,
169 rt_nullsys, /* stop */
170 rt_nullsys, /* exit */
171 rt_nullsys, /* active */
172 rt_nullsys, /* inactive */
173 rt_swapin,
174 rt_swapout,
175 rt_nullsys, /* trapret */
176 rt_preempt,
177 rt_setrun,
178 rt_nullsys, /* sleep */
179 rt_tick,
180 rt_wakeup,
181 rt_donice,
182 rt_globpri,
183 rt_nullsys, /* set_process_group */
184 rt_yield,
185 rt_doprio,
186 };
187
188 /*
189 * Real-time class initialization. Called by dispinit() at boot time.
190 * We can ignore the clparmsz argument since we know that the smallest
191 * possible parameter buffer is big enough for us.
192 */
193 /* ARGSUSED */
194 pri_t
rt_init(id_t cid,int clparmsz,classfuncs_t ** clfuncspp)195 rt_init(id_t cid, int clparmsz, classfuncs_t **clfuncspp)
196 {
197 rt_dptbl = rt_getdptbl();
198 rt_cid = cid; /* Record our class ID */
199
200 /*
201 * Initialize the rtproc list.
202 */
203 rt_plisthead.rt_next = rt_plisthead.rt_prev = &rt_plisthead;
204
205 /*
206 * We're required to return a pointer to our classfuncs
207 * structure and the highest global priority value we use.
208 */
209 *clfuncspp = &rt_classfuncs;
210 mutex_init(&rt_dptblock, NULL, MUTEX_DEFAULT, NULL);
211 mutex_init(&rt_list_lock, NULL, MUTEX_DEFAULT, NULL);
212 return (rt_dptbl[rt_maxpri].rt_globpri);
213 }
214
215 /*
216 * Get or reset the rt_dptbl values per the user's request.
217 */
218 /* ARGSUSED */
219 static int
rt_admin(caddr_t uaddr,cred_t * reqpcredp)220 rt_admin(caddr_t uaddr, cred_t *reqpcredp)
221 {
222 rtadmin_t rtadmin;
223 rtdpent_t *tmpdpp;
224 size_t userdpsz;
225 size_t rtdpsz;
226 int i;
227
228 if (get_udatamodel() == DATAMODEL_NATIVE) {
229 if (copyin(uaddr, &rtadmin, sizeof (rtadmin_t)))
230 return (EFAULT);
231 }
232 #ifdef _SYSCALL32_IMPL
233 else {
234 /* rtadmin struct from ILP32 callers */
235 rtadmin32_t rtadmin32;
236 if (copyin(uaddr, &rtadmin32, sizeof (rtadmin32_t)))
237 return (EFAULT);
238 rtadmin.rt_dpents =
239 (struct rtdpent *)(uintptr_t)rtadmin32.rt_dpents;
240 rtadmin.rt_ndpents = rtadmin32.rt_ndpents;
241 rtadmin.rt_cmd = rtadmin32.rt_cmd;
242 }
243 #endif /* _SYSCALL32_IMPL */
244
245 rtdpsz = (rt_maxpri + 1) * sizeof (rtdpent_t);
246
247 switch (rtadmin.rt_cmd) {
248
249 case RT_GETDPSIZE:
250 rtadmin.rt_ndpents = rt_maxpri + 1;
251
252 if (get_udatamodel() == DATAMODEL_NATIVE) {
253 if (copyout(&rtadmin, uaddr, sizeof (rtadmin_t)))
254 return (EFAULT);
255 }
256 #ifdef _SYSCALL32_IMPL
257 else {
258 /* return rtadmin struct to ILP32 callers */
259 rtadmin32_t rtadmin32;
260 rtadmin32.rt_dpents =
261 (caddr32_t)(uintptr_t)rtadmin.rt_dpents;
262 rtadmin32.rt_ndpents = rtadmin.rt_ndpents;
263 rtadmin32.rt_cmd = rtadmin.rt_cmd;
264 if (copyout(&rtadmin32, uaddr, sizeof (rtadmin32_t)))
265 return (EFAULT);
266 }
267 #endif /* _SYSCALL32_IMPL */
268
269 break;
270
271 case RT_GETDPTBL:
272 userdpsz = MIN(rtadmin.rt_ndpents * sizeof (rtdpent_t),
273 rtdpsz);
274 if (copyout(rt_dptbl, rtadmin.rt_dpents, userdpsz))
275 return (EFAULT);
276 rtadmin.rt_ndpents = userdpsz / sizeof (rtdpent_t);
277
278 if (get_udatamodel() == DATAMODEL_NATIVE) {
279 if (copyout(&rtadmin, uaddr, sizeof (rtadmin_t)))
280 return (EFAULT);
281 }
282 #ifdef _SYSCALL32_IMPL
283 else {
284 /* return rtadmin struct to ILP32 callers */
285 rtadmin32_t rtadmin32;
286 rtadmin32.rt_dpents =
287 (caddr32_t)(uintptr_t)rtadmin.rt_dpents;
288 rtadmin32.rt_ndpents = rtadmin.rt_ndpents;
289 rtadmin32.rt_cmd = rtadmin.rt_cmd;
290 if (copyout(&rtadmin32, uaddr, sizeof (rtadmin32_t)))
291 return (EFAULT);
292 }
293 #endif /* _SYSCALL32_IMPL */
294 break;
295
296 case RT_SETDPTBL:
297 /*
298 * We require that the requesting process has sufficient
299 * priveleges. We also require that the table supplied by
300 * the user exactly match the current rt_dptbl in size.
301 */
302 if (secpolicy_dispadm(reqpcredp) != 0)
303 return (EPERM);
304 if (rtadmin.rt_ndpents * sizeof (rtdpent_t) != rtdpsz)
305 return (EINVAL);
306
307 /*
308 * We read the user supplied table into a temporary buffer
309 * where the time quantum values are validated before
310 * being copied to the rt_dptbl.
311 */
312 tmpdpp = kmem_alloc(rtdpsz, KM_SLEEP);
313 if (copyin(rtadmin.rt_dpents, tmpdpp, rtdpsz)) {
314 kmem_free(tmpdpp, rtdpsz);
315 return (EFAULT);
316 }
317 for (i = 0; i < rtadmin.rt_ndpents; i++) {
318
319 /*
320 * Validate the user supplied time quantum values.
321 */
322 if (tmpdpp[i].rt_quantum <= 0 &&
323 tmpdpp[i].rt_quantum != RT_TQINF) {
324 kmem_free(tmpdpp, rtdpsz);
325 return (EINVAL);
326 }
327 }
328
329 /*
330 * Copy the user supplied values over the current rt_dptbl
331 * values. The rt_globpri member is read-only so we don't
332 * overwrite it.
333 */
334 mutex_enter(&rt_dptblock);
335 for (i = 0; i < rtadmin.rt_ndpents; i++)
336 rt_dptbl[i].rt_quantum = tmpdpp[i].rt_quantum;
337 mutex_exit(&rt_dptblock);
338 kmem_free(tmpdpp, rtdpsz);
339 break;
340
341 default:
342 return (EINVAL);
343 }
344 return (0);
345 }
346
347
348 /*
349 * Allocate a real-time class specific proc structure and
350 * initialize it with the parameters supplied. Also move thread
351 * to specified real-time priority.
352 */
353 /* ARGSUSED */
354 static int
rt_enterclass(kthread_t * t,id_t cid,void * parmsp,cred_t * reqpcredp,void * bufp)355 rt_enterclass(kthread_t *t, id_t cid, void *parmsp, cred_t *reqpcredp,
356 void *bufp)
357 {
358 rtkparms_t *rtkparmsp = (rtkparms_t *)parmsp;
359 rtproc_t *rtpp;
360
361 /*
362 * For a thread to enter the real-time class the thread
363 * which initiates the request must be privileged.
364 * This may have been checked previously but if our
365 * caller passed us a credential structure we assume it
366 * hasn't and we check it here.
367 */
368 if (reqpcredp != NULL && secpolicy_setpriority(reqpcredp) != 0)
369 return (EPERM);
370
371 rtpp = (rtproc_t *)bufp;
372 ASSERT(rtpp != NULL);
373
374 /*
375 * If this thread's lwp is swapped out, it will be brought in
376 * when it is put onto the runqueue.
377 *
378 * Now, Initialize the rtproc structure.
379 */
380 if (rtkparmsp == NULL) {
381 /*
382 * Use default values
383 */
384 rtpp->rt_pri = 0;
385 rtpp->rt_pquantum = rt_dptbl[0].rt_quantum;
386 rtpp->rt_tqsignal = 0;
387 } else {
388 /*
389 * Use supplied values
390 */
391 if ((rtkparmsp->rt_cflags & RT_DOPRI) == 0)
392 rtpp->rt_pri = 0;
393 else
394 rtpp->rt_pri = rtkparmsp->rt_pri;
395
396 if (rtkparmsp->rt_tqntm == RT_TQINF)
397 rtpp->rt_pquantum = RT_TQINF;
398 else if (rtkparmsp->rt_tqntm == RT_TQDEF ||
399 (rtkparmsp->rt_cflags & RT_DOTQ) == 0)
400 rtpp->rt_pquantum = rt_dptbl[rtpp->rt_pri].rt_quantum;
401 else
402 rtpp->rt_pquantum = rtkparmsp->rt_tqntm;
403
404 if ((rtkparmsp->rt_cflags & RT_DOSIG) == 0)
405 rtpp->rt_tqsignal = 0;
406 else
407 rtpp->rt_tqsignal = rtkparmsp->rt_tqsig;
408 }
409 rtpp->rt_flags = 0;
410 rtpp->rt_tp = t;
411 /*
412 * Reset thread priority
413 */
414 thread_lock(t);
415 t->t_clfuncs = &(sclass[cid].cl_funcs->thread);
416 t->t_cid = cid;
417 t->t_cldata = (void *)rtpp;
418 t->t_schedflag &= ~TS_RUNQMATCH;
419 rt_change_priority(t, rtpp);
420 thread_unlock(t);
421 /*
422 * Link new structure into rtproc list
423 */
424 mutex_enter(&rt_list_lock);
425 rtpp->rt_next = rt_plisthead.rt_next;
426 rtpp->rt_prev = &rt_plisthead;
427 rt_plisthead.rt_next->rt_prev = rtpp;
428 rt_plisthead.rt_next = rtpp;
429 mutex_exit(&rt_list_lock);
430 return (0);
431 }
432
433
434 /*
435 * Free rtproc structure of thread.
436 */
437 static void
rt_exitclass(void * procp)438 rt_exitclass(void *procp)
439 {
440 rtproc_t *rtprocp = (rtproc_t *)procp;
441
442 mutex_enter(&rt_list_lock);
443 rtprocp->rt_prev->rt_next = rtprocp->rt_next;
444 rtprocp->rt_next->rt_prev = rtprocp->rt_prev;
445 mutex_exit(&rt_list_lock);
446 kmem_free(rtprocp, sizeof (rtproc_t));
447 }
448
449
450 /*
451 * Allocate and initialize real-time class specific
452 * proc structure for child.
453 */
454 /* ARGSUSED */
455 static int
rt_fork(kthread_t * t,kthread_t * ct,void * bufp)456 rt_fork(kthread_t *t, kthread_t *ct, void *bufp)
457 {
458 rtproc_t *prtpp;
459 rtproc_t *crtpp;
460
461 ASSERT(MUTEX_HELD(&ttoproc(t)->p_lock));
462
463 /*
464 * Initialize child's rtproc structure
465 */
466 crtpp = (rtproc_t *)bufp;
467 ASSERT(crtpp != NULL);
468 prtpp = (rtproc_t *)t->t_cldata;
469 thread_lock(t);
470 crtpp->rt_timeleft = crtpp->rt_pquantum = prtpp->rt_pquantum;
471 crtpp->rt_pri = prtpp->rt_pri;
472 crtpp->rt_flags = prtpp->rt_flags & ~RTBACKQ;
473 crtpp->rt_tqsignal = prtpp->rt_tqsignal;
474
475 crtpp->rt_tp = ct;
476 thread_unlock(t);
477
478 /*
479 * Link new structure into rtproc list
480 */
481 ct->t_cldata = (void *)crtpp;
482 mutex_enter(&rt_list_lock);
483 crtpp->rt_next = rt_plisthead.rt_next;
484 crtpp->rt_prev = &rt_plisthead;
485 rt_plisthead.rt_next->rt_prev = crtpp;
486 rt_plisthead.rt_next = crtpp;
487 mutex_exit(&rt_list_lock);
488 return (0);
489 }
490
491
492 /*
493 * The child goes to the back of its dispatcher queue while the
494 * parent continues to run after a real time thread forks.
495 */
496 /* ARGSUSED */
497 static void
rt_forkret(kthread_t * t,kthread_t * ct)498 rt_forkret(kthread_t *t, kthread_t *ct)
499 {
500 proc_t *pp = ttoproc(t);
501 proc_t *cp = ttoproc(ct);
502
503 ASSERT(t == curthread);
504 ASSERT(MUTEX_HELD(&pidlock));
505
506 /*
507 * Grab the child's p_lock before dropping pidlock to ensure
508 * the process does not disappear before we set it running.
509 */
510 mutex_enter(&cp->p_lock);
511 mutex_exit(&pidlock);
512 continuelwps(cp);
513 mutex_exit(&cp->p_lock);
514
515 mutex_enter(&pp->p_lock);
516 continuelwps(pp);
517 mutex_exit(&pp->p_lock);
518 }
519
520
521 /*
522 * Get information about the real-time class into the buffer
523 * pointed to by rtinfop. The maximum configured real-time
524 * priority is the only information we supply. We ignore the
525 * class and credential arguments because anyone can have this
526 * information.
527 */
528 /* ARGSUSED */
529 static int
rt_getclinfo(void * infop)530 rt_getclinfo(void *infop)
531 {
532 rtinfo_t *rtinfop = (rtinfo_t *)infop;
533 rtinfop->rt_maxpri = rt_maxpri;
534 return (0);
535 }
536
537 /*
538 * Return the user mode scheduling priority range.
539 */
540 static int
rt_getclpri(pcpri_t * pcprip)541 rt_getclpri(pcpri_t *pcprip)
542 {
543 pcprip->pc_clpmax = rt_maxpri;
544 pcprip->pc_clpmin = 0;
545 return (0);
546 }
547
548 static void
rt_nullsys()549 rt_nullsys()
550 {
551 }
552
553 /* ARGSUSED */
554 static int
rt_canexit(kthread_t * t,cred_t * cred)555 rt_canexit(kthread_t *t, cred_t *cred)
556 {
557 /*
558 * Thread can always leave RT class
559 */
560 return (0);
561 }
562
563 /*
564 * Get the real-time scheduling parameters of the thread pointed to by
565 * rtprocp into the buffer pointed to by rtkparmsp.
566 */
567 static void
rt_parmsget(kthread_t * t,void * parmsp)568 rt_parmsget(kthread_t *t, void *parmsp)
569 {
570 rtproc_t *rtprocp = (rtproc_t *)t->t_cldata;
571 rtkparms_t *rtkparmsp = (rtkparms_t *)parmsp;
572
573 rtkparmsp->rt_pri = rtprocp->rt_pri;
574 rtkparmsp->rt_tqntm = rtprocp->rt_pquantum;
575 rtkparmsp->rt_tqsig = rtprocp->rt_tqsignal;
576 }
577
578
579
580 /*
581 * Check the validity of the real-time parameters in the buffer
582 * pointed to by rtprmsp.
583 * We convert the rtparms buffer from the user supplied format to
584 * our internal format (i.e. time quantum expressed in ticks).
585 */
586 static int
rt_parmsin(void * prmsp)587 rt_parmsin(void *prmsp)
588 {
589 rtparms_t *rtprmsp = (rtparms_t *)prmsp;
590 longlong_t ticks;
591 uint_t cflags;
592
593 /*
594 * First check the validity of parameters and convert
595 * the buffer to kernel format.
596 */
597 if ((rtprmsp->rt_pri < 0 || rtprmsp->rt_pri > rt_maxpri) &&
598 rtprmsp->rt_pri != RT_NOCHANGE)
599 return (EINVAL);
600
601 cflags = (rtprmsp->rt_pri != RT_NOCHANGE ? RT_DOPRI : 0);
602
603 if ((rtprmsp->rt_tqsecs == 0 && rtprmsp->rt_tqnsecs == 0) ||
604 rtprmsp->rt_tqnsecs >= NANOSEC)
605 return (EINVAL);
606
607 if (rtprmsp->rt_tqnsecs != RT_NOCHANGE)
608 cflags |= RT_DOTQ;
609
610 if (rtprmsp->rt_tqnsecs >= 0) {
611 if ((ticks = SEC_TO_TICK((longlong_t)rtprmsp->rt_tqsecs) +
612 NSEC_TO_TICK_ROUNDUP(rtprmsp->rt_tqnsecs)) > INT_MAX)
613 return (ERANGE);
614
615 ((rtkparms_t *)rtprmsp)->rt_tqntm = (int)ticks;
616 } else {
617 if (rtprmsp->rt_tqnsecs != RT_NOCHANGE &&
618 rtprmsp->rt_tqnsecs != RT_TQINF &&
619 rtprmsp->rt_tqnsecs != RT_TQDEF)
620 return (EINVAL);
621
622 ((rtkparms_t *)rtprmsp)->rt_tqntm = rtprmsp->rt_tqnsecs;
623 }
624 ((rtkparms_t *)rtprmsp)->rt_cflags = cflags;
625
626 return (0);
627 }
628
629
630 /*
631 * Check the validity of the real-time parameters in the pc_vaparms_t
632 * structure vaparmsp and put them in the buffer pointed to by rtprmsp.
633 * pc_vaparms_t contains (key, value) pairs of parameter.
634 * rt_vaparmsin() is the variable parameter version of rt_parmsin().
635 */
636 static int
rt_vaparmsin(void * prmsp,pc_vaparms_t * vaparmsp)637 rt_vaparmsin(void *prmsp, pc_vaparms_t *vaparmsp)
638 {
639 uint_t secs = 0;
640 uint_t cnt;
641 int nsecs = 0;
642 int priflag, secflag, nsecflag, sigflag;
643 longlong_t ticks;
644 rtkparms_t *rtprmsp = (rtkparms_t *)prmsp;
645 pc_vaparm_t *vpp = &vaparmsp->pc_parms[0];
646
647
648 /*
649 * First check the validity of parameters and convert them
650 * from the user supplied format to the internal format.
651 */
652 priflag = secflag = nsecflag = sigflag = 0;
653 rtprmsp->rt_cflags = 0;
654
655 if (vaparmsp->pc_vaparmscnt > PC_VAPARMCNT)
656 return (EINVAL);
657
658 for (cnt = 0; cnt < vaparmsp->pc_vaparmscnt; cnt++, vpp++) {
659
660 switch (vpp->pc_key) {
661 case RT_KY_PRI:
662 if (priflag++)
663 return (EINVAL);
664 rtprmsp->rt_cflags |= RT_DOPRI;
665 rtprmsp->rt_pri = (pri_t)vpp->pc_parm;
666 if (rtprmsp->rt_pri < 0 || rtprmsp->rt_pri > rt_maxpri)
667 return (EINVAL);
668 break;
669
670 case RT_KY_TQSECS:
671 if (secflag++)
672 return (EINVAL);
673 rtprmsp->rt_cflags |= RT_DOTQ;
674 secs = (uint_t)vpp->pc_parm;
675 break;
676
677 case RT_KY_TQNSECS:
678 if (nsecflag++)
679 return (EINVAL);
680 rtprmsp->rt_cflags |= RT_DOTQ;
681 nsecs = (int)vpp->pc_parm;
682 break;
683
684 case RT_KY_TQSIG:
685 if (sigflag++)
686 return (EINVAL);
687 rtprmsp->rt_cflags |= RT_DOSIG;
688 rtprmsp->rt_tqsig = (int)vpp->pc_parm;
689 if (rtprmsp->rt_tqsig < 0 || rtprmsp->rt_tqsig >= NSIG)
690 return (EINVAL);
691 break;
692
693 default:
694 return (EINVAL);
695 }
696 }
697
698 if (vaparmsp->pc_vaparmscnt == 0) {
699 /*
700 * Use default parameters.
701 */
702 rtprmsp->rt_pri = 0;
703 rtprmsp->rt_tqntm = RT_TQDEF;
704 rtprmsp->rt_tqsig = 0;
705 rtprmsp->rt_cflags = RT_DOPRI | RT_DOTQ | RT_DOSIG;
706 } else if ((rtprmsp->rt_cflags & RT_DOTQ) != 0) {
707 if ((secs == 0 && nsecs == 0) || nsecs >= NANOSEC)
708 return (EINVAL);
709
710 if (nsecs >= 0) {
711 if ((ticks = SEC_TO_TICK((longlong_t)secs) +
712 NSEC_TO_TICK_ROUNDUP(nsecs)) > INT_MAX)
713 return (ERANGE);
714
715 rtprmsp->rt_tqntm = (int)ticks;
716 } else {
717 if (nsecs != RT_TQINF && nsecs != RT_TQDEF)
718 return (EINVAL);
719 rtprmsp->rt_tqntm = nsecs;
720 }
721 }
722
723 return (0);
724 }
725
726 /*
727 * Do required processing on the real-time parameter buffer
728 * before it is copied out to the user.
729 * All we have to do is convert the buffer from kernel to user format
730 * (i.e. convert time quantum from ticks to seconds-nanoseconds).
731 */
732 /* ARGSUSED */
733 static int
rt_parmsout(void * prmsp,pc_vaparms_t * vaparmsp)734 rt_parmsout(void *prmsp, pc_vaparms_t *vaparmsp)
735 {
736 rtkparms_t *rtkprmsp = (rtkparms_t *)prmsp;
737
738 if (vaparmsp != NULL)
739 return (0);
740
741 if (rtkprmsp->rt_tqntm < 0) {
742 /*
743 * Quantum field set to special value (e.g. RT_TQINF)
744 */
745 ((rtparms_t *)rtkprmsp)->rt_tqnsecs = rtkprmsp->rt_tqntm;
746 ((rtparms_t *)rtkprmsp)->rt_tqsecs = 0;
747 } else {
748 /* Convert quantum from ticks to seconds-nanoseconds */
749
750 timestruc_t ts;
751 TICK_TO_TIMESTRUC(rtkprmsp->rt_tqntm, &ts);
752 ((rtparms_t *)rtkprmsp)->rt_tqsecs = ts.tv_sec;
753 ((rtparms_t *)rtkprmsp)->rt_tqnsecs = ts.tv_nsec;
754 }
755
756 return (0);
757 }
758
759
760 /*
761 * Copy all selected real-time class parameters to the user.
762 * The parameters are specified by a key.
763 */
764 static int
rt_vaparmsout(void * prmsp,pc_vaparms_t * vaparmsp)765 rt_vaparmsout(void *prmsp, pc_vaparms_t *vaparmsp)
766 {
767 rtkparms_t *rtkprmsp = (rtkparms_t *)prmsp;
768 timestruc_t ts;
769 uint_t cnt;
770 uint_t secs;
771 int nsecs;
772 int priflag, secflag, nsecflag, sigflag;
773 pc_vaparm_t *vpp = &vaparmsp->pc_parms[0];
774
775 ASSERT(MUTEX_NOT_HELD(&curproc->p_lock));
776
777 priflag = secflag = nsecflag = sigflag = 0;
778
779 if (vaparmsp->pc_vaparmscnt > PC_VAPARMCNT)
780 return (EINVAL);
781
782 if (rtkprmsp->rt_tqntm < 0) {
783 /*
784 * Quantum field set to special value (e.g. RT_TQINF).
785 */
786 secs = 0;
787 nsecs = rtkprmsp->rt_tqntm;
788 } else {
789 /*
790 * Convert quantum from ticks to seconds-nanoseconds.
791 */
792 TICK_TO_TIMESTRUC(rtkprmsp->rt_tqntm, &ts);
793 secs = ts.tv_sec;
794 nsecs = ts.tv_nsec;
795 }
796
797
798 for (cnt = 0; cnt < vaparmsp->pc_vaparmscnt; cnt++, vpp++) {
799
800 switch (vpp->pc_key) {
801 case RT_KY_PRI:
802 if (priflag++)
803 return (EINVAL);
804 if (copyout(&rtkprmsp->rt_pri,
805 (caddr_t)(uintptr_t)vpp->pc_parm, sizeof (pri_t)))
806 return (EFAULT);
807 break;
808
809 case RT_KY_TQSECS:
810 if (secflag++)
811 return (EINVAL);
812 if (copyout(&secs, (caddr_t)(uintptr_t)vpp->pc_parm,
813 sizeof (uint_t)))
814 return (EFAULT);
815 break;
816
817 case RT_KY_TQNSECS:
818 if (nsecflag++)
819 return (EINVAL);
820 if (copyout(&nsecs, (caddr_t)(uintptr_t)vpp->pc_parm,
821 sizeof (int)))
822 return (EFAULT);
823 break;
824
825 case RT_KY_TQSIG:
826 if (sigflag++)
827 return (EINVAL);
828 if (copyout(&rtkprmsp->rt_tqsig,
829 (caddr_t)(uintptr_t)vpp->pc_parm, sizeof (int)))
830 return (EFAULT);
831 break;
832
833 default:
834 return (EINVAL);
835 }
836 }
837
838 return (0);
839 }
840
841
842 /*
843 * Set the scheduling parameters of the thread pointed to by rtprocp
844 * to those specified in the buffer pointed to by rtkprmsp.
845 * Note that the parameters are expected to be in kernel format
846 * (i.e. time quantm expressed in ticks). Real time parameters copied
847 * in from the user should be processed by rt_parmsin() before they are
848 * passed to this function.
849 */
850 static int
rt_parmsset(kthread_t * tx,void * prmsp,id_t reqpcid,cred_t * reqpcredp)851 rt_parmsset(kthread_t *tx, void *prmsp, id_t reqpcid, cred_t *reqpcredp)
852 {
853 rtkparms_t *rtkprmsp = (rtkparms_t *)prmsp;
854 rtproc_t *rtpp = (rtproc_t *)tx->t_cldata;
855
856 ASSERT(MUTEX_HELD(&(ttoproc(tx))->p_lock));
857
858 /*
859 * Basic permissions enforced by generic kernel code
860 * for all classes require that a thread attempting
861 * to change the scheduling parameters of a target thread
862 * be privileged or have a real or effective UID
863 * matching that of the target thread. We are not
864 * called unless these basic permission checks have
865 * already passed. The real-time class requires in addition
866 * that the requesting thread be real-time unless it is privileged.
867 * This may also have been checked previously but if our caller
868 * passes us a credential structure we assume it hasn't and
869 * we check it here.
870 */
871 if (reqpcredp != NULL && reqpcid != rt_cid &&
872 secpolicy_raisepriority(reqpcredp) != 0)
873 return (EPERM);
874
875 thread_lock(tx);
876 if ((rtkprmsp->rt_cflags & RT_DOPRI) != 0) {
877 rtpp->rt_pri = rtkprmsp->rt_pri;
878 rt_change_priority(tx, rtpp);
879 }
880 if (rtkprmsp->rt_tqntm == RT_TQINF)
881 rtpp->rt_pquantum = RT_TQINF;
882 else if (rtkprmsp->rt_tqntm == RT_TQDEF)
883 rtpp->rt_timeleft = rtpp->rt_pquantum =
884 rt_dptbl[rtpp->rt_pri].rt_quantum;
885 else if ((rtkprmsp->rt_cflags & RT_DOTQ) != 0)
886 rtpp->rt_timeleft = rtpp->rt_pquantum = rtkprmsp->rt_tqntm;
887
888 if ((rtkprmsp->rt_cflags & RT_DOSIG) != 0)
889 rtpp->rt_tqsignal = rtkprmsp->rt_tqsig;
890
891 thread_unlock(tx);
892 return (0);
893 }
894
895
896 /*
897 * Arrange for thread to be placed in appropriate location
898 * on dispatcher queue. Runs at splhi() since the clock
899 * interrupt can cause RTBACKQ to be set.
900 */
901 static void
rt_preempt(kthread_t * t)902 rt_preempt(kthread_t *t)
903 {
904 rtproc_t *rtpp = (rtproc_t *)(t->t_cldata);
905 klwp_t *lwp;
906
907 ASSERT(THREAD_LOCK_HELD(t));
908
909 /*
910 * If the state is user I allow swapping because I know I won't
911 * be holding any locks.
912 */
913 if ((lwp = curthread->t_lwp) != NULL && lwp->lwp_state == LWP_USER)
914 t->t_schedflag &= ~TS_DONT_SWAP;
915 if ((rtpp->rt_flags & RTBACKQ) != 0) {
916 rtpp->rt_timeleft = rtpp->rt_pquantum;
917 rtpp->rt_flags &= ~RTBACKQ;
918 setbackdq(t);
919 } else
920 setfrontdq(t);
921
922 }
923
924 /*
925 * Return the global priority associated with this rt_pri.
926 */
927 static pri_t
rt_globpri(kthread_t * t)928 rt_globpri(kthread_t *t)
929 {
930 rtproc_t *rtprocp = (rtproc_t *)t->t_cldata;
931 return (rt_dptbl[rtprocp->rt_pri].rt_globpri);
932 }
933
934 static void
rt_setrun(kthread_t * t)935 rt_setrun(kthread_t *t)
936 {
937 rtproc_t *rtpp = (rtproc_t *)(t->t_cldata);
938
939 ASSERT(THREAD_LOCK_HELD(t));
940
941 rtpp->rt_timeleft = rtpp->rt_pquantum;
942 rtpp->rt_flags &= ~RTBACKQ;
943 setbackdq(t);
944 }
945
946 /*
947 * Returns the priority of the thread, -1 if the thread is loaded or ineligible
948 * for swapin.
949 *
950 * FX and RT threads are designed so that they don't swapout; however, it
951 * is possible that while the thread is swapped out and in another class, it
952 * can be changed to FX or RT. Since these threads should be swapped in as
953 * soon as they're runnable, rt_swapin returns SHRT_MAX, and fx_swapin
954 * returns SHRT_MAX - 1, so that it gives deference to any swapped out RT
955 * threads.
956 */
957 /* ARGSUSED */
958 static pri_t
rt_swapin(kthread_t * t,int flags)959 rt_swapin(kthread_t *t, int flags)
960 {
961 pri_t tpri = -1;
962
963 ASSERT(THREAD_LOCK_HELD(t));
964
965 if (t->t_state == TS_RUN && (t->t_schedflag & TS_LOAD) == 0) {
966 tpri = (pri_t)SHRT_MAX;
967 }
968
969 return (tpri);
970 }
971
972 /*
973 * Return an effective priority for swapout.
974 */
975 /* ARGSUSED */
976 static pri_t
rt_swapout(kthread_t * t,int flags)977 rt_swapout(kthread_t *t, int flags)
978 {
979 ASSERT(THREAD_LOCK_HELD(t));
980
981 return (-1);
982 }
983
984 /*
985 * Check for time slice expiration (unless thread has infinite time
986 * slice). If time slice has expired arrange for thread to be preempted
987 * and placed on back of queue.
988 */
989 static void
rt_tick(kthread_t * t)990 rt_tick(kthread_t *t)
991 {
992 rtproc_t *rtpp = (rtproc_t *)(t->t_cldata);
993
994 ASSERT(MUTEX_HELD(&(ttoproc(t))->p_lock));
995
996 thread_lock(t);
997 if ((rtpp->rt_pquantum != RT_TQINF && --rtpp->rt_timeleft == 0) ||
998 (t->t_state == TS_ONPROC && DISP_MUST_SURRENDER(t))) {
999 if (rtpp->rt_timeleft == 0 && rtpp->rt_tqsignal) {
1000 thread_unlock(t);
1001 sigtoproc(ttoproc(t), t, rtpp->rt_tqsignal);
1002 thread_lock(t);
1003 }
1004 rtpp->rt_flags |= RTBACKQ;
1005 cpu_surrender(t);
1006 }
1007 thread_unlock(t);
1008 }
1009
1010
1011 /*
1012 * Place the thread waking up on the dispatcher queue.
1013 */
1014 static void
rt_wakeup(kthread_t * t)1015 rt_wakeup(kthread_t *t)
1016 {
1017 rtproc_t *rtpp = (rtproc_t *)(t->t_cldata);
1018
1019 ASSERT(THREAD_LOCK_HELD(t));
1020
1021 rtpp->rt_timeleft = rtpp->rt_pquantum;
1022 rtpp->rt_flags &= ~RTBACKQ;
1023 setbackdq(t);
1024 }
1025
1026 static void
rt_yield(kthread_t * t)1027 rt_yield(kthread_t *t)
1028 {
1029 rtproc_t *rtpp = (rtproc_t *)(t->t_cldata);
1030
1031 ASSERT(t == curthread);
1032 ASSERT(THREAD_LOCK_HELD(t));
1033
1034 rtpp->rt_flags &= ~RTBACKQ;
1035 setbackdq(t);
1036 }
1037
1038 /* ARGSUSED */
1039 static int
rt_donice(kthread_t * t,cred_t * cr,int incr,int * retvalp)1040 rt_donice(kthread_t *t, cred_t *cr, int incr, int *retvalp)
1041 {
1042 return (EINVAL);
1043 }
1044
1045 /*
1046 * Increment the priority of the specified thread by incr and
1047 * return the new value in *retvalp.
1048 */
1049 static int
rt_doprio(kthread_t * t,cred_t * cr,int incr,int * retvalp)1050 rt_doprio(kthread_t *t, cred_t *cr, int incr, int *retvalp)
1051 {
1052 int newpri;
1053 rtproc_t *rtpp = (rtproc_t *)(t->t_cldata);
1054 rtkparms_t rtkparms;
1055
1056 /* If there's no change to the priority, just return current setting */
1057 if (incr == 0) {
1058 *retvalp = rtpp->rt_pri;
1059 return (0);
1060 }
1061
1062 newpri = rtpp->rt_pri + incr;
1063 if (newpri > rt_maxpri || newpri < 0)
1064 return (EINVAL);
1065
1066 *retvalp = newpri;
1067 rtkparms.rt_pri = newpri;
1068 rtkparms.rt_tqntm = RT_NOCHANGE;
1069 rtkparms.rt_tqsig = 0;
1070 rtkparms.rt_cflags = RT_DOPRI;
1071 return (rt_parmsset(t, &rtkparms, rt_cid, cr));
1072 }
1073
1074 static int
rt_alloc(void ** p,int flag)1075 rt_alloc(void **p, int flag)
1076 {
1077 void *bufp;
1078 bufp = kmem_alloc(sizeof (rtproc_t), flag);
1079 if (bufp == NULL) {
1080 return (ENOMEM);
1081 } else {
1082 *p = bufp;
1083 return (0);
1084 }
1085 }
1086
1087 static void
rt_free(void * bufp)1088 rt_free(void *bufp)
1089 {
1090 if (bufp)
1091 kmem_free(bufp, sizeof (rtproc_t));
1092 }
1093
1094 static void
rt_change_priority(kthread_t * t,rtproc_t * rtpp)1095 rt_change_priority(kthread_t *t, rtproc_t *rtpp)
1096 {
1097 pri_t new_pri;
1098
1099 ASSERT(THREAD_LOCK_HELD(t));
1100
1101 new_pri = rt_dptbl[rtpp->rt_pri].rt_globpri;
1102
1103 t->t_cpri = rtpp->rt_pri;
1104 if (t == curthread || t->t_state == TS_ONPROC) {
1105 cpu_t *cp = t->t_disp_queue->disp_cpu;
1106 THREAD_CHANGE_PRI(t, new_pri);
1107 if (t == cp->cpu_dispthread)
1108 cp->cpu_dispatch_pri = DISP_PRIO(t);
1109 if (DISP_MUST_SURRENDER(t)) {
1110 rtpp->rt_flags |= RTBACKQ;
1111 cpu_surrender(t);
1112 } else {
1113 rtpp->rt_timeleft = rtpp->rt_pquantum;
1114 }
1115 } else {
1116 /*
1117 * When the priority of a thread is changed,
1118 * it may be necessary to adjust its position
1119 * on a sleep queue or dispatch queue. The
1120 * function thread_change_pri() accomplishes this.
1121 */
1122 if (thread_change_pri(t, new_pri, 0)) {
1123 /*
1124 * The thread was on a run queue.
1125 * Reset its CPU timeleft.
1126 */
1127 rtpp->rt_timeleft = rtpp->rt_pquantum;
1128 } else {
1129 rtpp->rt_flags |= RTBACKQ;
1130 }
1131 }
1132 }
1133