xref: /freebsd/sys/kern/kern_cpuset.c (revision 3eeb75112272ef9ef244a00bc73beef3a146856a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2008,  Jeffrey Roberson <jeff@freebsd.org>
5  * All rights reserved.
6  *
7  * Copyright (c) 2008 Nokia Corporation
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice unmodified, this list of conditions, and the following
15  *    disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  *
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include "opt_ddb.h"
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/sysctl.h>
41 #include <sys/ctype.h>
42 #include <sys/sysproto.h>
43 #include <sys/jail.h>
44 #include <sys/kernel.h>
45 #include <sys/lock.h>
46 #include <sys/malloc.h>
47 #include <sys/mutex.h>
48 #include <sys/priv.h>
49 #include <sys/proc.h>
50 #include <sys/refcount.h>
51 #include <sys/sched.h>
52 #include <sys/smp.h>
53 #include <sys/syscallsubr.h>
54 #include <sys/capsicum.h>
55 #include <sys/cpuset.h>
56 #include <sys/domainset.h>
57 #include <sys/sx.h>
58 #include <sys/queue.h>
59 #include <sys/libkern.h>
60 #include <sys/limits.h>
61 #include <sys/bus.h>
62 #include <sys/interrupt.h>
63 #include <sys/vmmeter.h>
64 
65 #include <vm/uma.h>
66 #include <vm/vm.h>
67 #include <vm/vm_object.h>
68 #include <vm/vm_extern.h>
69 
70 #ifdef DDB
71 #include <ddb/ddb.h>
72 #endif /* DDB */
73 
74 /*
75  * cpusets provide a mechanism for creating and manipulating sets of
76  * processors for the purpose of constraining the scheduling of threads to
77  * specific processors.
78  *
79  * Each process belongs to an identified set, by default this is set 1.  Each
80  * thread may further restrict the cpus it may run on to a subset of this
81  * named set.  This creates an anonymous set which other threads and processes
82  * may not join by number.
83  *
84  * The named set is referred to herein as the 'base' set to avoid ambiguity.
85  * This set is usually a child of a 'root' set while the anonymous set may
86  * simply be referred to as a mask.  In the syscall api these are referred to
87  * as the ROOT, CPUSET, and MASK levels where CPUSET is called 'base' here.
88  *
89  * Threads inherit their set from their creator whether it be anonymous or
90  * not.  This means that anonymous sets are immutable because they may be
91  * shared.  To modify an anonymous set a new set is created with the desired
92  * mask and the same parent as the existing anonymous set.  This gives the
93  * illusion of each thread having a private mask.
94  *
95  * Via the syscall apis a user may ask to retrieve or modify the root, base,
96  * or mask that is discovered via a pid, tid, or setid.  Modifying a set
97  * modifies all numbered and anonymous child sets to comply with the new mask.
98  * Modifying a pid or tid's mask applies only to that tid but must still
99  * exist within the assigned parent set.
100  *
101  * A thread may not be assigned to a group separate from other threads in
102  * the process.  This is to remove ambiguity when the setid is queried with
103  * a pid argument.  There is no other technical limitation.
104  *
105  * This somewhat complex arrangement is intended to make it easy for
106  * applications to query available processors and bind their threads to
107  * specific processors while also allowing administrators to dynamically
108  * reprovision by changing sets which apply to groups of processes.
109  *
110  * A simple application should not concern itself with sets at all and
111  * rather apply masks to its own threads via CPU_WHICH_TID and a -1 id
112  * meaning 'curthread'.  It may query available cpus for that tid with a
113  * getaffinity call using (CPU_LEVEL_CPUSET, CPU_WHICH_PID, -1, ...).
114  */
115 
116 LIST_HEAD(domainlist, domainset);
117 
118 static uma_zone_t cpuset_zone;
119 static uma_zone_t domainset_zone;
120 static struct mtx cpuset_lock;
121 static struct setlist cpuset_ids;
122 static struct domainlist cpuset_domains;
123 static struct unrhdr *cpuset_unr;
124 static struct cpuset *cpuset_zero, *cpuset_default, *cpuset_kernel;
125 static struct domainset domainset0, domainset2;
126 
127 /* Return the size of cpuset_t at the kernel level */
128 SYSCTL_INT(_kern_sched, OID_AUTO, cpusetsize, CTLFLAG_RD | CTLFLAG_CAPRD,
129     SYSCTL_NULL_INT_PTR, sizeof(cpuset_t), "sizeof(cpuset_t)");
130 
131 cpuset_t *cpuset_root;
132 cpuset_t cpuset_domain[MAXMEMDOM];
133 
134 static int domainset_valid(const struct domainset *, const struct domainset *);
135 
136 /*
137  * Find the first non-anonymous set starting from 'set'.
138  */
139 static struct cpuset *
140 cpuset_getbase(struct cpuset *set)
141 {
142 
143 	if (set->cs_id == CPUSET_INVALID)
144 		set = set->cs_parent;
145 	return (set);
146 }
147 
148 /*
149  * Walks up the tree from 'set' to find the root.
150  */
151 static struct cpuset *
152 cpuset_getroot(struct cpuset *set)
153 {
154 
155 	while ((set->cs_flags & CPU_SET_ROOT) == 0 && set->cs_parent != NULL)
156 		set = set->cs_parent;
157 	return (set);
158 }
159 
160 /*
161  * Acquire a reference to a cpuset, all pointers must be tracked with refs.
162  */
163 struct cpuset *
164 cpuset_ref(struct cpuset *set)
165 {
166 
167 	refcount_acquire(&set->cs_ref);
168 	return (set);
169 }
170 
171 /*
172  * Walks up the tree from 'set' to find the root.  Returns the root
173  * referenced.
174  */
175 static struct cpuset *
176 cpuset_refroot(struct cpuset *set)
177 {
178 
179 	return (cpuset_ref(cpuset_getroot(set)));
180 }
181 
182 /*
183  * Find the first non-anonymous set starting from 'set'.  Returns this set
184  * referenced.  May return the passed in set with an extra ref if it is
185  * not anonymous.
186  */
187 static struct cpuset *
188 cpuset_refbase(struct cpuset *set)
189 {
190 
191 	return (cpuset_ref(cpuset_getbase(set)));
192 }
193 
194 /*
195  * Release a reference in a context where it is safe to allocate.
196  */
197 void
198 cpuset_rel(struct cpuset *set)
199 {
200 	cpusetid_t id;
201 
202 	if (refcount_release(&set->cs_ref) == 0)
203 		return;
204 	mtx_lock_spin(&cpuset_lock);
205 	LIST_REMOVE(set, cs_siblings);
206 	id = set->cs_id;
207 	if (id != CPUSET_INVALID)
208 		LIST_REMOVE(set, cs_link);
209 	mtx_unlock_spin(&cpuset_lock);
210 	cpuset_rel(set->cs_parent);
211 	uma_zfree(cpuset_zone, set);
212 	if (id != CPUSET_INVALID)
213 		free_unr(cpuset_unr, id);
214 }
215 
216 /*
217  * Deferred release must be used when in a context that is not safe to
218  * allocate/free.  This places any unreferenced sets on the list 'head'.
219  */
220 static void
221 cpuset_rel_defer(struct setlist *head, struct cpuset *set)
222 {
223 
224 	if (refcount_release(&set->cs_ref) == 0)
225 		return;
226 	mtx_lock_spin(&cpuset_lock);
227 	LIST_REMOVE(set, cs_siblings);
228 	if (set->cs_id != CPUSET_INVALID)
229 		LIST_REMOVE(set, cs_link);
230 	LIST_INSERT_HEAD(head, set, cs_link);
231 	mtx_unlock_spin(&cpuset_lock);
232 }
233 
234 /*
235  * Complete a deferred release.  Removes the set from the list provided to
236  * cpuset_rel_defer.
237  */
238 static void
239 cpuset_rel_complete(struct cpuset *set)
240 {
241 	LIST_REMOVE(set, cs_link);
242 	cpuset_rel(set->cs_parent);
243 	uma_zfree(cpuset_zone, set);
244 }
245 
246 /*
247  * Find a set based on an id.  Returns it with a ref.
248  */
249 static struct cpuset *
250 cpuset_lookup(cpusetid_t setid, struct thread *td)
251 {
252 	struct cpuset *set;
253 
254 	if (setid == CPUSET_INVALID)
255 		return (NULL);
256 	mtx_lock_spin(&cpuset_lock);
257 	LIST_FOREACH(set, &cpuset_ids, cs_link)
258 		if (set->cs_id == setid)
259 			break;
260 	if (set)
261 		cpuset_ref(set);
262 	mtx_unlock_spin(&cpuset_lock);
263 
264 	KASSERT(td != NULL, ("[%s:%d] td is NULL", __func__, __LINE__));
265 	if (set != NULL && jailed(td->td_ucred)) {
266 		struct cpuset *jset, *tset;
267 
268 		jset = td->td_ucred->cr_prison->pr_cpuset;
269 		for (tset = set; tset != NULL; tset = tset->cs_parent)
270 			if (tset == jset)
271 				break;
272 		if (tset == NULL) {
273 			cpuset_rel(set);
274 			set = NULL;
275 		}
276 	}
277 
278 	return (set);
279 }
280 
281 /*
282  * Create a set in the space provided in 'set' with the provided parameters.
283  * The set is returned with a single ref.  May return EDEADLK if the set
284  * will have no valid cpu based on restrictions from the parent.
285  */
286 static int
287 _cpuset_create(struct cpuset *set, struct cpuset *parent,
288     const cpuset_t *mask, struct domainset *domain, cpusetid_t id)
289 {
290 
291 	if (domain == NULL)
292 		domain = parent->cs_domain;
293 	if (mask == NULL)
294 		mask = &parent->cs_mask;
295 	if (!CPU_OVERLAP(&parent->cs_mask, mask))
296 		return (EDEADLK);
297 	/* The domain must be prepared ahead of time. */
298 	if (!domainset_valid(parent->cs_domain, domain))
299 		return (EDEADLK);
300 	CPU_COPY(mask, &set->cs_mask);
301 	LIST_INIT(&set->cs_children);
302 	refcount_init(&set->cs_ref, 1);
303 	set->cs_flags = 0;
304 	mtx_lock_spin(&cpuset_lock);
305 	set->cs_domain = domain;
306 	CPU_AND(&set->cs_mask, &parent->cs_mask);
307 	set->cs_id = id;
308 	set->cs_parent = cpuset_ref(parent);
309 	LIST_INSERT_HEAD(&parent->cs_children, set, cs_siblings);
310 	if (set->cs_id != CPUSET_INVALID)
311 		LIST_INSERT_HEAD(&cpuset_ids, set, cs_link);
312 	mtx_unlock_spin(&cpuset_lock);
313 
314 	return (0);
315 }
316 
317 /*
318  * Create a new non-anonymous set with the requested parent and mask.  May
319  * return failures if the mask is invalid or a new number can not be
320  * allocated.
321  */
322 static int
323 cpuset_create(struct cpuset **setp, struct cpuset *parent, const cpuset_t *mask)
324 {
325 	struct cpuset *set;
326 	cpusetid_t id;
327 	int error;
328 
329 	id = alloc_unr(cpuset_unr);
330 	if (id == -1)
331 		return (ENFILE);
332 	*setp = set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
333 	error = _cpuset_create(set, parent, mask, NULL, id);
334 	if (error == 0)
335 		return (0);
336 	free_unr(cpuset_unr, id);
337 	uma_zfree(cpuset_zone, set);
338 
339 	return (error);
340 }
341 
342 static void
343 cpuset_freelist_add(struct setlist *list, int count)
344 {
345 	struct cpuset *set;
346 	int i;
347 
348 	for (i = 0; i < count; i++) {
349 		set = uma_zalloc(cpuset_zone, M_ZERO | M_WAITOK);
350 		LIST_INSERT_HEAD(list, set, cs_link);
351 	}
352 }
353 
354 static void
355 cpuset_freelist_init(struct setlist *list, int count)
356 {
357 
358 	LIST_INIT(list);
359 	cpuset_freelist_add(list, count);
360 }
361 
362 static void
363 cpuset_freelist_free(struct setlist *list)
364 {
365 	struct cpuset *set;
366 
367 	while ((set = LIST_FIRST(list)) != NULL) {
368 		LIST_REMOVE(set, cs_link);
369 		uma_zfree(cpuset_zone, set);
370 	}
371 }
372 
373 static void
374 domainset_freelist_add(struct domainlist *list, int count)
375 {
376 	struct domainset *set;
377 	int i;
378 
379 	for (i = 0; i < count; i++) {
380 		set = uma_zalloc(domainset_zone, M_ZERO | M_WAITOK);
381 		LIST_INSERT_HEAD(list, set, ds_link);
382 	}
383 }
384 
385 static void
386 domainset_freelist_init(struct domainlist *list, int count)
387 {
388 
389 	LIST_INIT(list);
390 	domainset_freelist_add(list, count);
391 }
392 
393 static void
394 domainset_freelist_free(struct domainlist *list)
395 {
396 	struct domainset *set;
397 
398 	while ((set = LIST_FIRST(list)) != NULL) {
399 		LIST_REMOVE(set, ds_link);
400 		uma_zfree(domainset_zone, set);
401 	}
402 }
403 
404 /* Copy a domainset preserving mask and policy. */
405 static void
406 domainset_copy(const struct domainset *from, struct domainset *to)
407 {
408 
409 	DOMAINSET_COPY(&from->ds_mask, &to->ds_mask);
410 	to->ds_policy = from->ds_policy;
411 	to->ds_prefer = from->ds_prefer;
412 }
413 
414 /* Return 1 if mask and policy are equal, otherwise 0. */
415 static int
416 domainset_equal(const struct domainset *one, const struct domainset *two)
417 {
418 
419 	return (DOMAINSET_CMP(&one->ds_mask, &two->ds_mask) == 0 &&
420 	    one->ds_policy == two->ds_policy &&
421 	    one->ds_prefer == two->ds_prefer);
422 }
423 
424 /* Return 1 if child is a valid subset of parent. */
425 static int
426 domainset_valid(const struct domainset *parent, const struct domainset *child)
427 {
428 	if (child->ds_policy != DOMAINSET_POLICY_PREFER)
429 		return (DOMAINSET_SUBSET(&parent->ds_mask, &child->ds_mask));
430 	return (DOMAINSET_ISSET(child->ds_prefer, &parent->ds_mask));
431 }
432 
433 static int
434 domainset_restrict(const struct domainset *parent,
435     const struct domainset *child)
436 {
437 	if (child->ds_policy != DOMAINSET_POLICY_PREFER)
438 		return (DOMAINSET_OVERLAP(&parent->ds_mask, &child->ds_mask));
439 	return (DOMAINSET_ISSET(child->ds_prefer, &parent->ds_mask));
440 }
441 
442 /*
443  * Lookup or create a domainset.  The key is provided in ds_mask and
444  * ds_policy.  If the domainset does not yet exist the storage in
445  * 'domain' is used to insert.  Otherwise this storage is freed to the
446  * domainset_zone and the existing domainset is returned.
447  */
448 static struct domainset *
449 _domainset_create(struct domainset *domain, struct domainlist *freelist)
450 {
451 	struct domainset *ndomain;
452 	int i, j, max;
453 
454 	mtx_lock_spin(&cpuset_lock);
455 	LIST_FOREACH(ndomain, &cpuset_domains, ds_link)
456 		if (domainset_equal(ndomain, domain))
457 			break;
458 	/*
459 	 * If the domain does not yet exist we insert it and initialize
460 	 * various iteration helpers which are not part of the key.
461 	 */
462 	if (ndomain == NULL) {
463 		LIST_INSERT_HEAD(&cpuset_domains, domain, ds_link);
464 		domain->ds_cnt = DOMAINSET_COUNT(&domain->ds_mask);
465 		max = DOMAINSET_FLS(&domain->ds_mask) + 1;
466 		for (i = 0, j = 0; i < max; i++)
467 			if (DOMAINSET_ISSET(i, &domain->ds_mask))
468 				domain->ds_order[j++] = i;
469 	}
470 	mtx_unlock_spin(&cpuset_lock);
471 	if (ndomain == NULL)
472 		return (domain);
473 	if (freelist != NULL)
474 		LIST_INSERT_HEAD(freelist, domain, ds_link);
475 	else
476 		uma_zfree(domainset_zone, domain);
477 	return (ndomain);
478 
479 }
480 
481 /*
482  * Create or lookup a domainset based on the key held in 'domain'.
483  */
484 struct domainset *
485 domainset_create(const struct domainset *domain)
486 {
487 	struct domainset *ndomain;
488 
489 	/*
490 	 * Validate the policy.  It must specify a useable policy number with
491 	 * only valid domains.  Preferred must include the preferred domain
492 	 * in the mask.
493 	 */
494 	if (domain->ds_policy <= DOMAINSET_POLICY_INVALID ||
495 	    domain->ds_policy > DOMAINSET_POLICY_MAX)
496 		return (NULL);
497 	if (domain->ds_policy == DOMAINSET_POLICY_PREFER &&
498 	    !DOMAINSET_ISSET(domain->ds_prefer, &domain->ds_mask))
499 		return (NULL);
500 	if (!DOMAINSET_SUBSET(&domainset0.ds_mask, &domain->ds_mask))
501 		return (NULL);
502 	ndomain = uma_zalloc(domainset_zone, M_WAITOK | M_ZERO);
503 	domainset_copy(domain, ndomain);
504 	return _domainset_create(ndomain, NULL);
505 }
506 
507 /*
508  * Update thread domainset pointers.
509  */
510 static void
511 domainset_notify(void)
512 {
513 	struct thread *td;
514 	struct proc *p;
515 
516 	sx_slock(&allproc_lock);
517 	FOREACH_PROC_IN_SYSTEM(p) {
518 		PROC_LOCK(p);
519 		if (p->p_state == PRS_NEW) {
520 			PROC_UNLOCK(p);
521 			continue;
522 		}
523 		FOREACH_THREAD_IN_PROC(p, td) {
524 			thread_lock(td);
525 			td->td_domain.dr_policy = td->td_cpuset->cs_domain;
526 			thread_unlock(td);
527 		}
528 		PROC_UNLOCK(p);
529 	}
530 	sx_sunlock(&allproc_lock);
531 	kernel_object->domain.dr_policy = cpuset_kernel->cs_domain;
532 }
533 
534 /*
535  * Create a new set that is a subset of a parent.
536  */
537 static struct domainset *
538 domainset_shadow(const struct domainset *pdomain,
539     const struct domainset *domain, struct domainlist *freelist)
540 {
541 	struct domainset *ndomain;
542 
543 	ndomain = LIST_FIRST(freelist);
544 	LIST_REMOVE(ndomain, ds_link);
545 
546 	/*
547 	 * Initialize the key from the request.
548 	 */
549 	domainset_copy(domain, ndomain);
550 
551 	/*
552 	 * Restrict the key by the parent.
553 	 */
554 	DOMAINSET_AND(&ndomain->ds_mask, &pdomain->ds_mask);
555 
556 	return _domainset_create(ndomain, freelist);
557 }
558 
559 /*
560  * Recursively check for errors that would occur from applying mask to
561  * the tree of sets starting at 'set'.  Checks for sets that would become
562  * empty as well as RDONLY flags.
563  */
564 static int
565 cpuset_testupdate(struct cpuset *set, cpuset_t *mask, int check_mask)
566 {
567 	struct cpuset *nset;
568 	cpuset_t newmask;
569 	int error;
570 
571 	mtx_assert(&cpuset_lock, MA_OWNED);
572 	if (set->cs_flags & CPU_SET_RDONLY)
573 		return (EPERM);
574 	if (check_mask) {
575 		if (!CPU_OVERLAP(&set->cs_mask, mask))
576 			return (EDEADLK);
577 		CPU_COPY(&set->cs_mask, &newmask);
578 		CPU_AND(&newmask, mask);
579 	} else
580 		CPU_COPY(mask, &newmask);
581 	error = 0;
582 	LIST_FOREACH(nset, &set->cs_children, cs_siblings)
583 		if ((error = cpuset_testupdate(nset, &newmask, 1)) != 0)
584 			break;
585 	return (error);
586 }
587 
588 /*
589  * Applies the mask 'mask' without checking for empty sets or permissions.
590  */
591 static void
592 cpuset_update(struct cpuset *set, cpuset_t *mask)
593 {
594 	struct cpuset *nset;
595 
596 	mtx_assert(&cpuset_lock, MA_OWNED);
597 	CPU_AND(&set->cs_mask, mask);
598 	LIST_FOREACH(nset, &set->cs_children, cs_siblings)
599 		cpuset_update(nset, &set->cs_mask);
600 
601 	return;
602 }
603 
604 /*
605  * Modify the set 'set' to use a copy of the mask provided.  Apply this new
606  * mask to restrict all children in the tree.  Checks for validity before
607  * applying the changes.
608  */
609 static int
610 cpuset_modify(struct cpuset *set, cpuset_t *mask)
611 {
612 	struct cpuset *root;
613 	int error;
614 
615 	error = priv_check(curthread, PRIV_SCHED_CPUSET);
616 	if (error)
617 		return (error);
618 	/*
619 	 * In case we are called from within the jail
620 	 * we do not allow modifying the dedicated root
621 	 * cpuset of the jail but may still allow to
622 	 * change child sets.
623 	 */
624 	if (jailed(curthread->td_ucred) &&
625 	    set->cs_flags & CPU_SET_ROOT)
626 		return (EPERM);
627 	/*
628 	 * Verify that we have access to this set of
629 	 * cpus.
630 	 */
631 	root = cpuset_getroot(set);
632 	mtx_lock_spin(&cpuset_lock);
633 	if (root && !CPU_SUBSET(&root->cs_mask, mask)) {
634 		error = EINVAL;
635 		goto out;
636 	}
637 	error = cpuset_testupdate(set, mask, 0);
638 	if (error)
639 		goto out;
640 	CPU_COPY(mask, &set->cs_mask);
641 	cpuset_update(set, mask);
642 out:
643 	mtx_unlock_spin(&cpuset_lock);
644 
645 	return (error);
646 }
647 
648 /*
649  * Recursively check for errors that would occur from applying mask to
650  * the tree of sets starting at 'set'.  Checks for sets that would become
651  * empty as well as RDONLY flags.
652  */
653 static int
654 cpuset_testupdate_domain(struct cpuset *set, struct domainset *dset,
655     struct domainset *orig, int *count, int check_mask)
656 {
657 	struct cpuset *nset;
658 	struct domainset *domain;
659 	struct domainset newset;
660 	int error;
661 
662 	mtx_assert(&cpuset_lock, MA_OWNED);
663 	if (set->cs_flags & CPU_SET_RDONLY)
664 		return (EPERM);
665 	domain = set->cs_domain;
666 	domainset_copy(domain, &newset);
667 	if (!domainset_equal(domain, orig)) {
668 		if (!domainset_restrict(domain, dset))
669 			return (EDEADLK);
670 		DOMAINSET_AND(&newset.ds_mask, &dset->ds_mask);
671 		/* Count the number of domains that are changing. */
672 		(*count)++;
673 	}
674 	error = 0;
675 	LIST_FOREACH(nset, &set->cs_children, cs_siblings)
676 		if ((error = cpuset_testupdate_domain(nset, &newset, domain,
677 		    count, 1)) != 0)
678 			break;
679 	return (error);
680 }
681 
682 /*
683  * Applies the mask 'mask' without checking for empty sets or permissions.
684  */
685 static void
686 cpuset_update_domain(struct cpuset *set, struct domainset *domain,
687     struct domainset *orig, struct domainlist *domains)
688 {
689 	struct cpuset *nset;
690 
691 	mtx_assert(&cpuset_lock, MA_OWNED);
692 	/*
693 	 * If this domainset has changed from the parent we must calculate
694 	 * a new set.  Otherwise it simply inherits from the parent.  When
695 	 * we inherit from the parent we get a new mask and policy.  If the
696 	 * set is modified from the parent we keep the policy and only
697 	 * update the mask.
698 	 */
699 	if (set->cs_domain != orig) {
700 		orig = set->cs_domain;
701 		set->cs_domain = domainset_shadow(domain, orig, domains);
702 	} else
703 		set->cs_domain = domain;
704 	LIST_FOREACH(nset, &set->cs_children, cs_siblings)
705 		cpuset_update_domain(nset, set->cs_domain, orig, domains);
706 
707 	return;
708 }
709 
710 /*
711  * Modify the set 'set' to use a copy the domainset provided.  Apply this new
712  * mask to restrict all children in the tree.  Checks for validity before
713  * applying the changes.
714  */
715 static int
716 cpuset_modify_domain(struct cpuset *set, struct domainset *domain)
717 {
718 	struct domainlist domains;
719 	struct domainset temp;
720 	struct domainset *dset;
721 	struct cpuset *root;
722 	int ndomains, needed;
723 	int error;
724 
725 	error = priv_check(curthread, PRIV_SCHED_CPUSET);
726 	if (error)
727 		return (error);
728 	/*
729 	 * In case we are called from within the jail
730 	 * we do not allow modifying the dedicated root
731 	 * cpuset of the jail but may still allow to
732 	 * change child sets.
733 	 */
734 	if (jailed(curthread->td_ucred) &&
735 	    set->cs_flags & CPU_SET_ROOT)
736 		return (EPERM);
737 	domainset_freelist_init(&domains, 0);
738 	domain = domainset_create(domain);
739 	ndomains = needed = 0;
740 	do {
741 		if (ndomains < needed) {
742 			domainset_freelist_add(&domains, needed - ndomains);
743 			ndomains = needed;
744 		}
745 		root = cpuset_getroot(set);
746 		mtx_lock_spin(&cpuset_lock);
747 		dset = root->cs_domain;
748 		/*
749 		 * Verify that we have access to this set of domains.
750 		 */
751 		if (root && !domainset_valid(dset, domain)) {
752 			error = EINVAL;
753 			goto out;
754 		}
755 		/*
756 		 * If applying prefer we keep the current set as the fallback.
757 		 */
758 		if (domain->ds_policy == DOMAINSET_POLICY_PREFER)
759 			DOMAINSET_COPY(&set->cs_domain->ds_mask,
760 			    &domain->ds_mask);
761 		/*
762 		 * Determine whether we can apply this set of domains and
763 		 * how many new domain structures it will require.
764 		 */
765 		domainset_copy(domain, &temp);
766 		needed = 0;
767 		error = cpuset_testupdate_domain(set, &temp, set->cs_domain,
768 		    &needed, 0);
769 		if (error)
770 			goto out;
771 	} while (ndomains < needed);
772 	dset = set->cs_domain;
773 	cpuset_update_domain(set, domain, dset, &domains);
774 out:
775 	mtx_unlock_spin(&cpuset_lock);
776 	domainset_freelist_free(&domains);
777 	if (error == 0)
778 		domainset_notify();
779 
780 	return (error);
781 }
782 
783 /*
784  * Resolve the 'which' parameter of several cpuset apis.
785  *
786  * For WHICH_PID and WHICH_TID return a locked proc and valid proc/tid.  Also
787  * checks for permission via p_cansched().
788  *
789  * For WHICH_SET returns a valid set with a new reference.
790  *
791  * -1 may be supplied for any argument to mean the current proc/thread or
792  * the base set of the current thread.  May fail with ESRCH/EPERM.
793  */
794 int
795 cpuset_which(cpuwhich_t which, id_t id, struct proc **pp, struct thread **tdp,
796     struct cpuset **setp)
797 {
798 	struct cpuset *set;
799 	struct thread *td;
800 	struct proc *p;
801 	int error;
802 
803 	*pp = p = NULL;
804 	*tdp = td = NULL;
805 	*setp = set = NULL;
806 	switch (which) {
807 	case CPU_WHICH_PID:
808 		if (id == -1) {
809 			PROC_LOCK(curproc);
810 			p = curproc;
811 			break;
812 		}
813 		if ((p = pfind(id)) == NULL)
814 			return (ESRCH);
815 		break;
816 	case CPU_WHICH_TID:
817 		if (id == -1) {
818 			PROC_LOCK(curproc);
819 			p = curproc;
820 			td = curthread;
821 			break;
822 		}
823 		td = tdfind(id, -1);
824 		if (td == NULL)
825 			return (ESRCH);
826 		p = td->td_proc;
827 		break;
828 	case CPU_WHICH_CPUSET:
829 		if (id == -1) {
830 			thread_lock(curthread);
831 			set = cpuset_refbase(curthread->td_cpuset);
832 			thread_unlock(curthread);
833 		} else
834 			set = cpuset_lookup(id, curthread);
835 		if (set) {
836 			*setp = set;
837 			return (0);
838 		}
839 		return (ESRCH);
840 	case CPU_WHICH_JAIL:
841 	{
842 		/* Find `set' for prison with given id. */
843 		struct prison *pr;
844 
845 		sx_slock(&allprison_lock);
846 		pr = prison_find_child(curthread->td_ucred->cr_prison, id);
847 		sx_sunlock(&allprison_lock);
848 		if (pr == NULL)
849 			return (ESRCH);
850 		cpuset_ref(pr->pr_cpuset);
851 		*setp = pr->pr_cpuset;
852 		mtx_unlock(&pr->pr_mtx);
853 		return (0);
854 	}
855 	case CPU_WHICH_IRQ:
856 	case CPU_WHICH_DOMAIN:
857 		return (0);
858 	default:
859 		return (EINVAL);
860 	}
861 	error = p_cansched(curthread, p);
862 	if (error) {
863 		PROC_UNLOCK(p);
864 		return (error);
865 	}
866 	if (td == NULL)
867 		td = FIRST_THREAD_IN_PROC(p);
868 	*pp = p;
869 	*tdp = td;
870 	return (0);
871 }
872 
873 static int
874 cpuset_testshadow(struct cpuset *set, const cpuset_t *mask,
875     const struct domainset *domain)
876 {
877 	struct cpuset *parent;
878 	struct domainset *dset;
879 
880 	parent = cpuset_getbase(set);
881 	/*
882 	 * If we are restricting a cpu mask it must be a subset of the
883 	 * parent or invalid CPUs have been specified.
884 	 */
885 	if (mask != NULL && !CPU_SUBSET(&parent->cs_mask, mask))
886 		return (EINVAL);
887 
888 	/*
889 	 * If we are restricting a domain mask it must be a subset of the
890 	 * parent or invalid domains have been specified.
891 	 */
892 	dset = parent->cs_domain;
893 	if (domain != NULL && !domainset_valid(dset, domain))
894 		return (EINVAL);
895 
896 	return (0);
897 }
898 
899 /*
900  * Create an anonymous set with the provided mask in the space provided by
901  * 'nset'.  If the passed in set is anonymous we use its parent otherwise
902  * the new set is a child of 'set'.
903  */
904 static int
905 cpuset_shadow(struct cpuset *set, struct cpuset **nsetp,
906    const cpuset_t *mask, const struct domainset *domain,
907    struct setlist *cpusets, struct domainlist *domains)
908 {
909 	struct cpuset *parent;
910 	struct cpuset *nset;
911 	struct domainset *dset;
912 	struct domainset *d;
913 	int error;
914 
915 	error = cpuset_testshadow(set, mask, domain);
916 	if (error)
917 		return (error);
918 
919 	parent = cpuset_getbase(set);
920 	dset = parent->cs_domain;
921 	if (mask == NULL)
922 		mask = &set->cs_mask;
923 	if (domain != NULL)
924 		d = domainset_shadow(dset, domain, domains);
925 	else
926 		d = set->cs_domain;
927 	nset = LIST_FIRST(cpusets);
928 	error = _cpuset_create(nset, parent, mask, d, CPUSET_INVALID);
929 	if (error == 0) {
930 		LIST_REMOVE(nset, cs_link);
931 		*nsetp = nset;
932 	}
933 	return (error);
934 }
935 
936 static struct cpuset *
937 cpuset_update_thread(struct thread *td, struct cpuset *nset)
938 {
939 	struct cpuset *tdset;
940 
941 	tdset = td->td_cpuset;
942 	td->td_cpuset = nset;
943 	td->td_domain.dr_policy = nset->cs_domain;
944 	sched_affinity(td);
945 
946 	return (tdset);
947 }
948 
949 static int
950 cpuset_setproc_test_maskthread(struct cpuset *tdset, cpuset_t *mask,
951     struct domainset *domain)
952 {
953 	struct cpuset *parent;
954 
955 	parent = cpuset_getbase(tdset);
956 	if (mask == NULL)
957 		mask = &tdset->cs_mask;
958 	if (domain == NULL)
959 		domain = tdset->cs_domain;
960 	return cpuset_testshadow(parent, mask, domain);
961 }
962 
963 static int
964 cpuset_setproc_maskthread(struct cpuset *tdset, cpuset_t *mask,
965     struct domainset *domain, struct cpuset **nsetp,
966     struct setlist *freelist, struct domainlist *domainlist)
967 {
968 	struct cpuset *parent;
969 
970 	parent = cpuset_getbase(tdset);
971 	if (mask == NULL)
972 		mask = &tdset->cs_mask;
973 	if (domain == NULL)
974 		domain = tdset->cs_domain;
975 	return cpuset_shadow(parent, nsetp, mask, domain, freelist,
976 	    domainlist);
977 }
978 
979 static int
980 cpuset_setproc_setthread_mask(struct cpuset *tdset, struct cpuset *set,
981     cpuset_t *mask, struct domainset *domain)
982 {
983 	struct cpuset *parent;
984 
985 	parent = cpuset_getbase(tdset);
986 
987 	/*
988 	 * If the thread restricted its mask then apply that same
989 	 * restriction to the new set, otherwise take it wholesale.
990 	 */
991 	if (CPU_CMP(&tdset->cs_mask, &parent->cs_mask) != 0) {
992 		CPU_COPY(&tdset->cs_mask, mask);
993 		CPU_AND(mask, &set->cs_mask);
994 	} else
995 		CPU_COPY(&set->cs_mask, mask);
996 
997 	/*
998 	 * If the thread restricted the domain then we apply the
999 	 * restriction to the new set but retain the policy.
1000 	 */
1001 	if (tdset->cs_domain != parent->cs_domain) {
1002 		domainset_copy(tdset->cs_domain, domain);
1003 		DOMAINSET_AND(&domain->ds_mask, &set->cs_domain->ds_mask);
1004 	} else
1005 		domainset_copy(set->cs_domain, domain);
1006 
1007 	if (CPU_EMPTY(mask) || DOMAINSET_EMPTY(&domain->ds_mask))
1008 		return (EDEADLK);
1009 
1010 	return (0);
1011 }
1012 
1013 static int
1014 cpuset_setproc_test_setthread(struct cpuset *tdset, struct cpuset *set)
1015 {
1016 	struct domainset domain;
1017 	cpuset_t mask;
1018 
1019 	if (tdset->cs_id != CPUSET_INVALID)
1020 		return (0);
1021 	return cpuset_setproc_setthread_mask(tdset, set, &mask, &domain);
1022 }
1023 
1024 static int
1025 cpuset_setproc_setthread(struct cpuset *tdset, struct cpuset *set,
1026     struct cpuset **nsetp, struct setlist *freelist,
1027     struct domainlist *domainlist)
1028 {
1029 	struct domainset domain;
1030 	cpuset_t mask;
1031 	int error;
1032 
1033 	/*
1034 	 * If we're replacing on a thread that has not constrained the
1035 	 * original set we can simply accept the new set.
1036 	 */
1037 	if (tdset->cs_id != CPUSET_INVALID) {
1038 		*nsetp = cpuset_ref(set);
1039 		return (0);
1040 	}
1041 	error = cpuset_setproc_setthread_mask(tdset, set, &mask, &domain);
1042 	if (error)
1043 		return (error);
1044 
1045 	return cpuset_shadow(tdset, nsetp, &mask, &domain, freelist,
1046 	    domainlist);
1047 }
1048 
1049 /*
1050  * Handle three cases for updating an entire process.
1051  *
1052  * 1) Set is non-null.  This reparents all anonymous sets to the provided
1053  *    set and replaces all non-anonymous td_cpusets with the provided set.
1054  * 2) Mask is non-null.  This replaces or creates anonymous sets for every
1055  *    thread with the existing base as a parent.
1056  * 3) domain is non-null.  This creates anonymous sets for every thread
1057  *    and replaces the domain set.
1058  *
1059  * This is overly complicated because we can't allocate while holding a
1060  * spinlock and spinlocks must be held while changing and examining thread
1061  * state.
1062  */
1063 static int
1064 cpuset_setproc(pid_t pid, struct cpuset *set, cpuset_t *mask,
1065     struct domainset *domain)
1066 {
1067 	struct setlist freelist;
1068 	struct setlist droplist;
1069 	struct domainlist domainlist;
1070 	struct cpuset *nset;
1071 	struct thread *td;
1072 	struct proc *p;
1073 	int threads;
1074 	int nfree;
1075 	int error;
1076 
1077 	/*
1078 	 * The algorithm requires two passes due to locking considerations.
1079 	 *
1080 	 * 1) Lookup the process and acquire the locks in the required order.
1081 	 * 2) If enough cpusets have not been allocated release the locks and
1082 	 *    allocate them.  Loop.
1083 	 */
1084 	cpuset_freelist_init(&freelist, 1);
1085 	domainset_freelist_init(&domainlist, 1);
1086 	nfree = 1;
1087 	LIST_INIT(&droplist);
1088 	nfree = 0;
1089 	for (;;) {
1090 		error = cpuset_which(CPU_WHICH_PID, pid, &p, &td, &nset);
1091 		if (error)
1092 			goto out;
1093 		if (nfree >= p->p_numthreads)
1094 			break;
1095 		threads = p->p_numthreads;
1096 		PROC_UNLOCK(p);
1097 		if (nfree < threads) {
1098 			cpuset_freelist_add(&freelist, threads - nfree);
1099 			domainset_freelist_add(&domainlist, threads - nfree);
1100 			nfree = threads;
1101 		}
1102 	}
1103 	PROC_LOCK_ASSERT(p, MA_OWNED);
1104 	/*
1105 	 * Now that the appropriate locks are held and we have enough cpusets,
1106 	 * make sure the operation will succeed before applying changes. The
1107 	 * proc lock prevents td_cpuset from changing between calls.
1108 	 */
1109 	error = 0;
1110 	FOREACH_THREAD_IN_PROC(p, td) {
1111 		thread_lock(td);
1112 		if (set != NULL)
1113 			error = cpuset_setproc_test_setthread(td->td_cpuset,
1114 			    set);
1115 		else
1116 			error = cpuset_setproc_test_maskthread(td->td_cpuset,
1117 			    mask, domain);
1118 		thread_unlock(td);
1119 		if (error)
1120 			goto unlock_out;
1121 	}
1122 	/*
1123 	 * Replace each thread's cpuset while using deferred release.  We
1124 	 * must do this because the thread lock must be held while operating
1125 	 * on the thread and this limits the type of operations allowed.
1126 	 */
1127 	FOREACH_THREAD_IN_PROC(p, td) {
1128 		thread_lock(td);
1129 		if (set != NULL)
1130 			error = cpuset_setproc_setthread(td->td_cpuset, set,
1131 			    &nset, &freelist, &domainlist);
1132 		else
1133 			error = cpuset_setproc_maskthread(td->td_cpuset, mask,
1134 			    domain, &nset, &freelist, &domainlist);
1135 		if (error) {
1136 			thread_unlock(td);
1137 			break;
1138 		}
1139 		cpuset_rel_defer(&droplist, cpuset_update_thread(td, nset));
1140 		thread_unlock(td);
1141 	}
1142 unlock_out:
1143 	PROC_UNLOCK(p);
1144 out:
1145 	while ((nset = LIST_FIRST(&droplist)) != NULL)
1146 		cpuset_rel_complete(nset);
1147 	cpuset_freelist_free(&freelist);
1148 	domainset_freelist_free(&domainlist);
1149 	return (error);
1150 }
1151 
1152 static int
1153 bitset_strprint(char *buf, size_t bufsiz, const struct bitset *set, int setlen)
1154 {
1155 	size_t bytes;
1156 	int i, once;
1157 	char *p;
1158 
1159 	once = 0;
1160 	p = buf;
1161 	for (i = 0; i < __bitset_words(setlen); i++) {
1162 		if (once != 0) {
1163 			if (bufsiz < 1)
1164 				return (0);
1165 			*p = ',';
1166 			p++;
1167 			bufsiz--;
1168 		} else
1169 			once = 1;
1170 		if (bufsiz < sizeof(__STRING(ULONG_MAX)))
1171 			return (0);
1172 		bytes = snprintf(p, bufsiz, "%lx", set->__bits[i]);
1173 		p += bytes;
1174 		bufsiz -= bytes;
1175 	}
1176 	return (p - buf);
1177 }
1178 
1179 static int
1180 bitset_strscan(struct bitset *set, int setlen, const char *buf)
1181 {
1182 	int i, ret;
1183 	const char *p;
1184 
1185 	BIT_ZERO(setlen, set);
1186 	p = buf;
1187 	for (i = 0; i < __bitset_words(setlen); i++) {
1188 		if (*p == ',') {
1189 			p++;
1190 			continue;
1191 		}
1192 		ret = sscanf(p, "%lx", &set->__bits[i]);
1193 		if (ret == 0 || ret == -1)
1194 			break;
1195 		while (isxdigit(*p))
1196 			p++;
1197 	}
1198 	return (p - buf);
1199 }
1200 
1201 /*
1202  * Return a string representing a valid layout for a cpuset_t object.
1203  * It expects an incoming buffer at least sized as CPUSETBUFSIZ.
1204  */
1205 char *
1206 cpusetobj_strprint(char *buf, const cpuset_t *set)
1207 {
1208 
1209 	bitset_strprint(buf, CPUSETBUFSIZ, (const struct bitset *)set,
1210 	    CPU_SETSIZE);
1211 	return (buf);
1212 }
1213 
1214 /*
1215  * Build a valid cpuset_t object from a string representation.
1216  * It expects an incoming buffer at least sized as CPUSETBUFSIZ.
1217  */
1218 int
1219 cpusetobj_strscan(cpuset_t *set, const char *buf)
1220 {
1221 	char p;
1222 
1223 	if (strlen(buf) > CPUSETBUFSIZ - 1)
1224 		return (-1);
1225 
1226 	p = buf[bitset_strscan((struct bitset *)set, CPU_SETSIZE, buf)];
1227 	if (p != '\0')
1228 		return (-1);
1229 
1230 	return (0);
1231 }
1232 
1233 /*
1234  * Handle a domainset specifier in the sysctl tree.  A poiner to a pointer to
1235  * a domainset is in arg1.  If the user specifies a valid domainset the
1236  * pointer is updated.
1237  *
1238  * Format is:
1239  * hex mask word 0,hex mask word 1,...:decimal policy:decimal preferred
1240  */
1241 int
1242 sysctl_handle_domainset(SYSCTL_HANDLER_ARGS)
1243 {
1244 	char buf[DOMAINSETBUFSIZ];
1245 	struct domainset *dset;
1246 	struct domainset key;
1247 	int policy, prefer, error;
1248 	char *p;
1249 
1250 	dset = *(struct domainset **)arg1;
1251 	error = 0;
1252 
1253 	if (dset != NULL) {
1254 		p = buf + bitset_strprint(buf, DOMAINSETBUFSIZ,
1255 		    (const struct bitset *)&dset->ds_mask, DOMAINSET_SETSIZE);
1256 		sprintf(p, ":%d:%d", dset->ds_policy, dset->ds_prefer);
1257 	} else
1258 		sprintf(buf, "<NULL>");
1259 	error = sysctl_handle_string(oidp, buf, sizeof(buf), req);
1260 	if (error != 0 || req->newptr == NULL)
1261 		return (error);
1262 
1263 	/*
1264 	 * Read in and validate the string.
1265 	 */
1266 	memset(&key, 0, sizeof(key));
1267 	p = &buf[bitset_strscan((struct bitset *)&key.ds_mask,
1268 	    DOMAINSET_SETSIZE, buf)];
1269 	if (p == buf)
1270 		return (EINVAL);
1271 	if (sscanf(p, ":%d:%d", &policy, &prefer) != 2)
1272 		return (EINVAL);
1273 	key.ds_policy = policy;
1274 	key.ds_prefer = prefer;
1275 
1276 	/* Domainset_create() validates the policy.*/
1277 	dset = domainset_create(&key);
1278 	if (dset == NULL)
1279 		return (EINVAL);
1280 	*(struct domainset **)arg1 = dset;
1281 
1282 	return (error);
1283 }
1284 
1285 /*
1286  * Apply an anonymous mask or a domain to a single thread.
1287  */
1288 static int
1289 _cpuset_setthread(lwpid_t id, cpuset_t *mask, struct domainset *domain)
1290 {
1291 	struct setlist cpusets;
1292 	struct domainlist domainlist;
1293 	struct cpuset *nset;
1294 	struct cpuset *set;
1295 	struct thread *td;
1296 	struct proc *p;
1297 	int error;
1298 
1299 	cpuset_freelist_init(&cpusets, 1);
1300 	domainset_freelist_init(&domainlist, domain != NULL);
1301 	error = cpuset_which(CPU_WHICH_TID, id, &p, &td, &set);
1302 	if (error)
1303 		goto out;
1304 	set = NULL;
1305 	thread_lock(td);
1306 	error = cpuset_shadow(td->td_cpuset, &nset, mask, domain,
1307 	    &cpusets, &domainlist);
1308 	if (error == 0)
1309 		set = cpuset_update_thread(td, nset);
1310 	thread_unlock(td);
1311 	PROC_UNLOCK(p);
1312 	if (set)
1313 		cpuset_rel(set);
1314 out:
1315 	cpuset_freelist_free(&cpusets);
1316 	domainset_freelist_free(&domainlist);
1317 	return (error);
1318 }
1319 
1320 /*
1321  * Apply an anonymous mask to a single thread.
1322  */
1323 int
1324 cpuset_setthread(lwpid_t id, cpuset_t *mask)
1325 {
1326 
1327 	return _cpuset_setthread(id, mask, NULL);
1328 }
1329 
1330 /*
1331  * Apply new cpumask to the ithread.
1332  */
1333 int
1334 cpuset_setithread(lwpid_t id, int cpu)
1335 {
1336 	cpuset_t mask;
1337 
1338 	CPU_ZERO(&mask);
1339 	if (cpu == NOCPU)
1340 		CPU_COPY(cpuset_root, &mask);
1341 	else
1342 		CPU_SET(cpu, &mask);
1343 	return _cpuset_setthread(id, &mask, NULL);
1344 }
1345 
1346 /*
1347  * Create the domainset for cpuset 0, 1 and cpuset 2.
1348  */
1349 void
1350 domainset_zero(void)
1351 {
1352 	struct domainset *dset;
1353 	int i;
1354 
1355 	mtx_init(&cpuset_lock, "cpuset", NULL, MTX_SPIN | MTX_RECURSE);
1356 
1357 	dset = &domainset0;
1358 	DOMAINSET_ZERO(&dset->ds_mask);
1359 	for (i = 0; i < vm_ndomains; i++)
1360 		DOMAINSET_SET(i, &dset->ds_mask);
1361 	dset->ds_policy = DOMAINSET_POLICY_FIRSTTOUCH;
1362 	dset->ds_prefer = -1;
1363 	curthread->td_domain.dr_policy = _domainset_create(dset, NULL);
1364 
1365 	domainset_copy(dset, &domainset2);
1366 	domainset2.ds_policy = DOMAINSET_POLICY_INTERLEAVE;
1367 	kernel_object->domain.dr_policy = _domainset_create(&domainset2, NULL);
1368 }
1369 
1370 /*
1371  * Creates system-wide cpusets and the cpuset for thread0 including three
1372  * sets:
1373  *
1374  * 0 - The root set which should represent all valid processors in the
1375  *     system.  It is initially created with a mask of all processors
1376  *     because we don't know what processors are valid until cpuset_init()
1377  *     runs.  This set is immutable.
1378  * 1 - The default set which all processes are a member of until changed.
1379  *     This allows an administrator to move all threads off of given cpus to
1380  *     dedicate them to high priority tasks or save power etc.
1381  * 2 - The kernel set which allows restriction and policy to be applied only
1382  *     to kernel threads and the kernel_object.
1383  */
1384 struct cpuset *
1385 cpuset_thread0(void)
1386 {
1387 	struct cpuset *set;
1388 	int error;
1389 	int i;
1390 
1391 	cpuset_zone = uma_zcreate("cpuset", sizeof(struct cpuset), NULL, NULL,
1392 	    NULL, NULL, UMA_ALIGN_CACHE, 0);
1393 	domainset_zone = uma_zcreate("domainset", sizeof(struct domainset),
1394 	    NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
1395 
1396 	/*
1397 	 * Create the root system set (0) for the whole machine.  Doesn't use
1398 	 * cpuset_create() due to NULL parent.
1399 	 */
1400 	set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
1401 	CPU_COPY(&all_cpus, &set->cs_mask);
1402 	LIST_INIT(&set->cs_children);
1403 	LIST_INSERT_HEAD(&cpuset_ids, set, cs_link);
1404 	set->cs_ref = 1;
1405 	set->cs_flags = CPU_SET_ROOT | CPU_SET_RDONLY;
1406 	set->cs_domain = &domainset0;
1407 	cpuset_zero = set;
1408 	cpuset_root = &set->cs_mask;
1409 
1410 	/*
1411 	 * Now derive a default (1), modifiable set from that to give out.
1412 	 */
1413 	set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
1414 	error = _cpuset_create(set, cpuset_zero, NULL, NULL, 1);
1415 	KASSERT(error == 0, ("Error creating default set: %d\n", error));
1416 	cpuset_default = set;
1417 	/*
1418 	 * Create the kernel set (2).
1419 	 */
1420 	set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
1421 	error = _cpuset_create(set, cpuset_zero, NULL, NULL, 2);
1422 	KASSERT(error == 0, ("Error creating kernel set: %d\n", error));
1423 	set->cs_domain = &domainset2;
1424 	cpuset_kernel = set;
1425 
1426 	/*
1427 	 * Initialize the unit allocator. 0 and 1 are allocated above.
1428 	 */
1429 	cpuset_unr = new_unrhdr(2, INT_MAX, NULL);
1430 
1431 	/*
1432 	 * If MD code has not initialized per-domain cpusets, place all
1433 	 * CPUs in domain 0.
1434 	 */
1435 	for (i = 0; i < MAXMEMDOM; i++)
1436 		if (!CPU_EMPTY(&cpuset_domain[i]))
1437 			goto domains_set;
1438 	CPU_COPY(&all_cpus, &cpuset_domain[0]);
1439 domains_set:
1440 
1441 	return (cpuset_default);
1442 }
1443 
1444 void
1445 cpuset_kernthread(struct thread *td)
1446 {
1447 	struct cpuset *set;
1448 
1449 	thread_lock(td);
1450 	set = td->td_cpuset;
1451 	td->td_cpuset = cpuset_ref(cpuset_kernel);
1452 	thread_unlock(td);
1453 	cpuset_rel(set);
1454 }
1455 
1456 /*
1457  * Create a cpuset, which would be cpuset_create() but
1458  * mark the new 'set' as root.
1459  *
1460  * We are not going to reparent the td to it.  Use cpuset_setproc_update_set()
1461  * for that.
1462  *
1463  * In case of no error, returns the set in *setp locked with a reference.
1464  */
1465 int
1466 cpuset_create_root(struct prison *pr, struct cpuset **setp)
1467 {
1468 	struct cpuset *set;
1469 	int error;
1470 
1471 	KASSERT(pr != NULL, ("[%s:%d] invalid pr", __func__, __LINE__));
1472 	KASSERT(setp != NULL, ("[%s:%d] invalid setp", __func__, __LINE__));
1473 
1474 	error = cpuset_create(setp, pr->pr_cpuset, &pr->pr_cpuset->cs_mask);
1475 	if (error)
1476 		return (error);
1477 
1478 	KASSERT(*setp != NULL, ("[%s:%d] cpuset_create returned invalid data",
1479 	    __func__, __LINE__));
1480 
1481 	/* Mark the set as root. */
1482 	set = *setp;
1483 	set->cs_flags |= CPU_SET_ROOT;
1484 
1485 	return (0);
1486 }
1487 
1488 int
1489 cpuset_setproc_update_set(struct proc *p, struct cpuset *set)
1490 {
1491 	int error;
1492 
1493 	KASSERT(p != NULL, ("[%s:%d] invalid proc", __func__, __LINE__));
1494 	KASSERT(set != NULL, ("[%s:%d] invalid set", __func__, __LINE__));
1495 
1496 	cpuset_ref(set);
1497 	error = cpuset_setproc(p->p_pid, set, NULL, NULL);
1498 	if (error)
1499 		return (error);
1500 	cpuset_rel(set);
1501 	return (0);
1502 }
1503 
1504 #ifndef _SYS_SYSPROTO_H_
1505 struct cpuset_args {
1506 	cpusetid_t	*setid;
1507 };
1508 #endif
1509 int
1510 sys_cpuset(struct thread *td, struct cpuset_args *uap)
1511 {
1512 	struct cpuset *root;
1513 	struct cpuset *set;
1514 	int error;
1515 
1516 	thread_lock(td);
1517 	root = cpuset_refroot(td->td_cpuset);
1518 	thread_unlock(td);
1519 	error = cpuset_create(&set, root, &root->cs_mask);
1520 	cpuset_rel(root);
1521 	if (error)
1522 		return (error);
1523 	error = copyout(&set->cs_id, uap->setid, sizeof(set->cs_id));
1524 	if (error == 0)
1525 		error = cpuset_setproc(-1, set, NULL, NULL);
1526 	cpuset_rel(set);
1527 	return (error);
1528 }
1529 
1530 #ifndef _SYS_SYSPROTO_H_
1531 struct cpuset_setid_args {
1532 	cpuwhich_t	which;
1533 	id_t		id;
1534 	cpusetid_t	setid;
1535 };
1536 #endif
1537 int
1538 sys_cpuset_setid(struct thread *td, struct cpuset_setid_args *uap)
1539 {
1540 
1541 	return (kern_cpuset_setid(td, uap->which, uap->id, uap->setid));
1542 }
1543 
1544 int
1545 kern_cpuset_setid(struct thread *td, cpuwhich_t which,
1546     id_t id, cpusetid_t setid)
1547 {
1548 	struct cpuset *set;
1549 	int error;
1550 
1551 	/*
1552 	 * Presently we only support per-process sets.
1553 	 */
1554 	if (which != CPU_WHICH_PID)
1555 		return (EINVAL);
1556 	set = cpuset_lookup(setid, td);
1557 	if (set == NULL)
1558 		return (ESRCH);
1559 	error = cpuset_setproc(id, set, NULL, NULL);
1560 	cpuset_rel(set);
1561 	return (error);
1562 }
1563 
1564 #ifndef _SYS_SYSPROTO_H_
1565 struct cpuset_getid_args {
1566 	cpulevel_t	level;
1567 	cpuwhich_t	which;
1568 	id_t		id;
1569 	cpusetid_t	*setid;
1570 };
1571 #endif
1572 int
1573 sys_cpuset_getid(struct thread *td, struct cpuset_getid_args *uap)
1574 {
1575 
1576 	return (kern_cpuset_getid(td, uap->level, uap->which, uap->id,
1577 	    uap->setid));
1578 }
1579 
1580 int
1581 kern_cpuset_getid(struct thread *td, cpulevel_t level, cpuwhich_t which,
1582     id_t id, cpusetid_t *setid)
1583 {
1584 	struct cpuset *nset;
1585 	struct cpuset *set;
1586 	struct thread *ttd;
1587 	struct proc *p;
1588 	cpusetid_t tmpid;
1589 	int error;
1590 
1591 	if (level == CPU_LEVEL_WHICH && which != CPU_WHICH_CPUSET)
1592 		return (EINVAL);
1593 	error = cpuset_which(which, id, &p, &ttd, &set);
1594 	if (error)
1595 		return (error);
1596 	switch (which) {
1597 	case CPU_WHICH_TID:
1598 	case CPU_WHICH_PID:
1599 		thread_lock(ttd);
1600 		set = cpuset_refbase(ttd->td_cpuset);
1601 		thread_unlock(ttd);
1602 		PROC_UNLOCK(p);
1603 		break;
1604 	case CPU_WHICH_CPUSET:
1605 	case CPU_WHICH_JAIL:
1606 		break;
1607 	case CPU_WHICH_IRQ:
1608 	case CPU_WHICH_DOMAIN:
1609 		return (EINVAL);
1610 	}
1611 	switch (level) {
1612 	case CPU_LEVEL_ROOT:
1613 		nset = cpuset_refroot(set);
1614 		cpuset_rel(set);
1615 		set = nset;
1616 		break;
1617 	case CPU_LEVEL_CPUSET:
1618 		break;
1619 	case CPU_LEVEL_WHICH:
1620 		break;
1621 	}
1622 	tmpid = set->cs_id;
1623 	cpuset_rel(set);
1624 	if (error == 0)
1625 		error = copyout(&tmpid, setid, sizeof(tmpid));
1626 
1627 	return (error);
1628 }
1629 
1630 #ifndef _SYS_SYSPROTO_H_
1631 struct cpuset_getaffinity_args {
1632 	cpulevel_t	level;
1633 	cpuwhich_t	which;
1634 	id_t		id;
1635 	size_t		cpusetsize;
1636 	cpuset_t	*mask;
1637 };
1638 #endif
1639 int
1640 sys_cpuset_getaffinity(struct thread *td, struct cpuset_getaffinity_args *uap)
1641 {
1642 
1643 	return (kern_cpuset_getaffinity(td, uap->level, uap->which,
1644 	    uap->id, uap->cpusetsize, uap->mask));
1645 }
1646 
1647 int
1648 kern_cpuset_getaffinity(struct thread *td, cpulevel_t level, cpuwhich_t which,
1649     id_t id, size_t cpusetsize, cpuset_t *maskp)
1650 {
1651 	struct thread *ttd;
1652 	struct cpuset *nset;
1653 	struct cpuset *set;
1654 	struct proc *p;
1655 	cpuset_t *mask;
1656 	int error;
1657 	size_t size;
1658 
1659 	if (cpusetsize < sizeof(cpuset_t) || cpusetsize > CPU_MAXSIZE / NBBY)
1660 		return (ERANGE);
1661 	/* In Capability mode, you can only get your own CPU set. */
1662 	if (IN_CAPABILITY_MODE(td)) {
1663 		if (level != CPU_LEVEL_WHICH)
1664 			return (ECAPMODE);
1665 		if (which != CPU_WHICH_TID && which != CPU_WHICH_PID)
1666 			return (ECAPMODE);
1667 		if (id != -1)
1668 			return (ECAPMODE);
1669 	}
1670 	size = cpusetsize;
1671 	mask = malloc(size, M_TEMP, M_WAITOK | M_ZERO);
1672 	error = cpuset_which(which, id, &p, &ttd, &set);
1673 	if (error)
1674 		goto out;
1675 	switch (level) {
1676 	case CPU_LEVEL_ROOT:
1677 	case CPU_LEVEL_CPUSET:
1678 		switch (which) {
1679 		case CPU_WHICH_TID:
1680 		case CPU_WHICH_PID:
1681 			thread_lock(ttd);
1682 			set = cpuset_ref(ttd->td_cpuset);
1683 			thread_unlock(ttd);
1684 			break;
1685 		case CPU_WHICH_CPUSET:
1686 		case CPU_WHICH_JAIL:
1687 			break;
1688 		case CPU_WHICH_IRQ:
1689 		case CPU_WHICH_INTRHANDLER:
1690 		case CPU_WHICH_ITHREAD:
1691 		case CPU_WHICH_DOMAIN:
1692 			error = EINVAL;
1693 			goto out;
1694 		}
1695 		if (level == CPU_LEVEL_ROOT)
1696 			nset = cpuset_refroot(set);
1697 		else
1698 			nset = cpuset_refbase(set);
1699 		CPU_COPY(&nset->cs_mask, mask);
1700 		cpuset_rel(nset);
1701 		break;
1702 	case CPU_LEVEL_WHICH:
1703 		switch (which) {
1704 		case CPU_WHICH_TID:
1705 			thread_lock(ttd);
1706 			CPU_COPY(&ttd->td_cpuset->cs_mask, mask);
1707 			thread_unlock(ttd);
1708 			break;
1709 		case CPU_WHICH_PID:
1710 			FOREACH_THREAD_IN_PROC(p, ttd) {
1711 				thread_lock(ttd);
1712 				CPU_OR(mask, &ttd->td_cpuset->cs_mask);
1713 				thread_unlock(ttd);
1714 			}
1715 			break;
1716 		case CPU_WHICH_CPUSET:
1717 		case CPU_WHICH_JAIL:
1718 			CPU_COPY(&set->cs_mask, mask);
1719 			break;
1720 		case CPU_WHICH_IRQ:
1721 		case CPU_WHICH_INTRHANDLER:
1722 		case CPU_WHICH_ITHREAD:
1723 			error = intr_getaffinity(id, which, mask);
1724 			break;
1725 		case CPU_WHICH_DOMAIN:
1726 			if (id < 0 || id >= MAXMEMDOM)
1727 				error = ESRCH;
1728 			else
1729 				CPU_COPY(&cpuset_domain[id], mask);
1730 			break;
1731 		}
1732 		break;
1733 	default:
1734 		error = EINVAL;
1735 		break;
1736 	}
1737 	if (set)
1738 		cpuset_rel(set);
1739 	if (p)
1740 		PROC_UNLOCK(p);
1741 	if (error == 0)
1742 		error = copyout(mask, maskp, size);
1743 out:
1744 	free(mask, M_TEMP);
1745 	return (error);
1746 }
1747 
1748 #ifndef _SYS_SYSPROTO_H_
1749 struct cpuset_setaffinity_args {
1750 	cpulevel_t	level;
1751 	cpuwhich_t	which;
1752 	id_t		id;
1753 	size_t		cpusetsize;
1754 	const cpuset_t	*mask;
1755 };
1756 #endif
1757 int
1758 sys_cpuset_setaffinity(struct thread *td, struct cpuset_setaffinity_args *uap)
1759 {
1760 
1761 	return (kern_cpuset_setaffinity(td, uap->level, uap->which,
1762 	    uap->id, uap->cpusetsize, uap->mask));
1763 }
1764 
1765 int
1766 kern_cpuset_setaffinity(struct thread *td, cpulevel_t level, cpuwhich_t which,
1767     id_t id, size_t cpusetsize, const cpuset_t *maskp)
1768 {
1769 	struct cpuset *nset;
1770 	struct cpuset *set;
1771 	struct thread *ttd;
1772 	struct proc *p;
1773 	cpuset_t *mask;
1774 	int error;
1775 
1776 	if (cpusetsize < sizeof(cpuset_t) || cpusetsize > CPU_MAXSIZE / NBBY)
1777 		return (ERANGE);
1778 	/* In Capability mode, you can only set your own CPU set. */
1779 	if (IN_CAPABILITY_MODE(td)) {
1780 		if (level != CPU_LEVEL_WHICH)
1781 			return (ECAPMODE);
1782 		if (which != CPU_WHICH_TID && which != CPU_WHICH_PID)
1783 			return (ECAPMODE);
1784 		if (id != -1)
1785 			return (ECAPMODE);
1786 	}
1787 	mask = malloc(cpusetsize, M_TEMP, M_WAITOK | M_ZERO);
1788 	error = copyin(maskp, mask, cpusetsize);
1789 	if (error)
1790 		goto out;
1791 	/*
1792 	 * Verify that no high bits are set.
1793 	 */
1794 	if (cpusetsize > sizeof(cpuset_t)) {
1795 		char *end;
1796 		char *cp;
1797 
1798 		end = cp = (char *)&mask->__bits;
1799 		end += cpusetsize;
1800 		cp += sizeof(cpuset_t);
1801 		while (cp != end)
1802 			if (*cp++ != 0) {
1803 				error = EINVAL;
1804 				goto out;
1805 			}
1806 
1807 	}
1808 	switch (level) {
1809 	case CPU_LEVEL_ROOT:
1810 	case CPU_LEVEL_CPUSET:
1811 		error = cpuset_which(which, id, &p, &ttd, &set);
1812 		if (error)
1813 			break;
1814 		switch (which) {
1815 		case CPU_WHICH_TID:
1816 		case CPU_WHICH_PID:
1817 			thread_lock(ttd);
1818 			set = cpuset_ref(ttd->td_cpuset);
1819 			thread_unlock(ttd);
1820 			PROC_UNLOCK(p);
1821 			break;
1822 		case CPU_WHICH_CPUSET:
1823 		case CPU_WHICH_JAIL:
1824 			break;
1825 		case CPU_WHICH_IRQ:
1826 		case CPU_WHICH_INTRHANDLER:
1827 		case CPU_WHICH_ITHREAD:
1828 		case CPU_WHICH_DOMAIN:
1829 			error = EINVAL;
1830 			goto out;
1831 		}
1832 		if (level == CPU_LEVEL_ROOT)
1833 			nset = cpuset_refroot(set);
1834 		else
1835 			nset = cpuset_refbase(set);
1836 		error = cpuset_modify(nset, mask);
1837 		cpuset_rel(nset);
1838 		cpuset_rel(set);
1839 		break;
1840 	case CPU_LEVEL_WHICH:
1841 		switch (which) {
1842 		case CPU_WHICH_TID:
1843 			error = cpuset_setthread(id, mask);
1844 			break;
1845 		case CPU_WHICH_PID:
1846 			error = cpuset_setproc(id, NULL, mask, NULL);
1847 			break;
1848 		case CPU_WHICH_CPUSET:
1849 		case CPU_WHICH_JAIL:
1850 			error = cpuset_which(which, id, &p, &ttd, &set);
1851 			if (error == 0) {
1852 				error = cpuset_modify(set, mask);
1853 				cpuset_rel(set);
1854 			}
1855 			break;
1856 		case CPU_WHICH_IRQ:
1857 		case CPU_WHICH_INTRHANDLER:
1858 		case CPU_WHICH_ITHREAD:
1859 			error = intr_setaffinity(id, which, mask);
1860 			break;
1861 		default:
1862 			error = EINVAL;
1863 			break;
1864 		}
1865 		break;
1866 	default:
1867 		error = EINVAL;
1868 		break;
1869 	}
1870 out:
1871 	free(mask, M_TEMP);
1872 	return (error);
1873 }
1874 
1875 #ifndef _SYS_SYSPROTO_H_
1876 struct cpuset_getdomain_args {
1877 	cpulevel_t	level;
1878 	cpuwhich_t	which;
1879 	id_t		id;
1880 	size_t		domainsetsize;
1881 	domainset_t	*mask;
1882 	int 		*policy;
1883 };
1884 #endif
1885 int
1886 sys_cpuset_getdomain(struct thread *td, struct cpuset_getdomain_args *uap)
1887 {
1888 
1889 	return (kern_cpuset_getdomain(td, uap->level, uap->which,
1890 	    uap->id, uap->domainsetsize, uap->mask, uap->policy));
1891 }
1892 
1893 int
1894 kern_cpuset_getdomain(struct thread *td, cpulevel_t level, cpuwhich_t which,
1895     id_t id, size_t domainsetsize, domainset_t *maskp, int *policyp)
1896 {
1897 	struct domainset outset;
1898 	struct thread *ttd;
1899 	struct cpuset *nset;
1900 	struct cpuset *set;
1901 	struct domainset *dset;
1902 	struct proc *p;
1903 	domainset_t *mask;
1904 	int error;
1905 
1906 	if (domainsetsize < sizeof(domainset_t) ||
1907 	    domainsetsize > DOMAINSET_MAXSIZE / NBBY)
1908 		return (ERANGE);
1909 	/* In Capability mode, you can only get your own domain set. */
1910 	if (IN_CAPABILITY_MODE(td)) {
1911 		if (level != CPU_LEVEL_WHICH)
1912 			return (ECAPMODE);
1913 		if (which != CPU_WHICH_TID && which != CPU_WHICH_PID)
1914 			return (ECAPMODE);
1915 		if (id != -1)
1916 			return (ECAPMODE);
1917 	}
1918 	mask = malloc(domainsetsize, M_TEMP, M_WAITOK | M_ZERO);
1919 	bzero(&outset, sizeof(outset));
1920 	error = cpuset_which(which, id, &p, &ttd, &set);
1921 	if (error)
1922 		goto out;
1923 	switch (level) {
1924 	case CPU_LEVEL_ROOT:
1925 	case CPU_LEVEL_CPUSET:
1926 		switch (which) {
1927 		case CPU_WHICH_TID:
1928 		case CPU_WHICH_PID:
1929 			thread_lock(ttd);
1930 			set = cpuset_ref(ttd->td_cpuset);
1931 			thread_unlock(ttd);
1932 			break;
1933 		case CPU_WHICH_CPUSET:
1934 		case CPU_WHICH_JAIL:
1935 			break;
1936 		case CPU_WHICH_IRQ:
1937 		case CPU_WHICH_INTRHANDLER:
1938 		case CPU_WHICH_ITHREAD:
1939 		case CPU_WHICH_DOMAIN:
1940 			error = EINVAL;
1941 			goto out;
1942 		}
1943 		if (level == CPU_LEVEL_ROOT)
1944 			nset = cpuset_refroot(set);
1945 		else
1946 			nset = cpuset_refbase(set);
1947 		domainset_copy(nset->cs_domain, &outset);
1948 		cpuset_rel(nset);
1949 		break;
1950 	case CPU_LEVEL_WHICH:
1951 		switch (which) {
1952 		case CPU_WHICH_TID:
1953 			thread_lock(ttd);
1954 			domainset_copy(ttd->td_cpuset->cs_domain, &outset);
1955 			thread_unlock(ttd);
1956 			break;
1957 		case CPU_WHICH_PID:
1958 			FOREACH_THREAD_IN_PROC(p, ttd) {
1959 				thread_lock(ttd);
1960 				dset = ttd->td_cpuset->cs_domain;
1961 				/* Show all domains in the proc. */
1962 				DOMAINSET_OR(&outset.ds_mask, &dset->ds_mask);
1963 				/* Last policy wins. */
1964 				outset.ds_policy = dset->ds_policy;
1965 				outset.ds_prefer = dset->ds_prefer;
1966 				thread_unlock(ttd);
1967 			}
1968 			break;
1969 		case CPU_WHICH_CPUSET:
1970 		case CPU_WHICH_JAIL:
1971 			domainset_copy(set->cs_domain, &outset);
1972 			break;
1973 		case CPU_WHICH_IRQ:
1974 		case CPU_WHICH_INTRHANDLER:
1975 		case CPU_WHICH_ITHREAD:
1976 		case CPU_WHICH_DOMAIN:
1977 			error = EINVAL;
1978 			break;
1979 		}
1980 		break;
1981 	default:
1982 		error = EINVAL;
1983 		break;
1984 	}
1985 	if (set)
1986 		cpuset_rel(set);
1987 	if (p)
1988 		PROC_UNLOCK(p);
1989 	/*
1990 	 * Translate prefer into a set containing only the preferred domain,
1991 	 * not the entire fallback set.
1992 	 */
1993 	if (outset.ds_policy == DOMAINSET_POLICY_PREFER) {
1994 		DOMAINSET_ZERO(&outset.ds_mask);
1995 		DOMAINSET_SET(outset.ds_prefer, &outset.ds_mask);
1996 	}
1997 	DOMAINSET_COPY(&outset.ds_mask, mask);
1998 	if (error == 0)
1999 		error = copyout(mask, maskp, domainsetsize);
2000 	if (error == 0)
2001 		if (suword32(policyp, outset.ds_policy) != 0)
2002 			error = EFAULT;
2003 out:
2004 	free(mask, M_TEMP);
2005 	return (error);
2006 }
2007 
2008 #ifndef _SYS_SYSPROTO_H_
2009 struct cpuset_setdomain_args {
2010 	cpulevel_t	level;
2011 	cpuwhich_t	which;
2012 	id_t		id;
2013 	size_t		domainsetsize;
2014 	domainset_t	*mask;
2015 	int 		policy;
2016 };
2017 #endif
2018 int
2019 sys_cpuset_setdomain(struct thread *td, struct cpuset_setdomain_args *uap)
2020 {
2021 
2022 	return (kern_cpuset_setdomain(td, uap->level, uap->which,
2023 	    uap->id, uap->domainsetsize, uap->mask, uap->policy));
2024 }
2025 
2026 int
2027 kern_cpuset_setdomain(struct thread *td, cpulevel_t level, cpuwhich_t which,
2028     id_t id, size_t domainsetsize, const domainset_t *maskp, int policy)
2029 {
2030 	struct cpuset *nset;
2031 	struct cpuset *set;
2032 	struct thread *ttd;
2033 	struct proc *p;
2034 	struct domainset domain;
2035 	domainset_t *mask;
2036 	int error;
2037 
2038 	if (domainsetsize < sizeof(domainset_t) ||
2039 	    domainsetsize > DOMAINSET_MAXSIZE / NBBY)
2040 		return (ERANGE);
2041 	/* In Capability mode, you can only set your own CPU set. */
2042 	if (IN_CAPABILITY_MODE(td)) {
2043 		if (level != CPU_LEVEL_WHICH)
2044 			return (ECAPMODE);
2045 		if (which != CPU_WHICH_TID && which != CPU_WHICH_PID)
2046 			return (ECAPMODE);
2047 		if (id != -1)
2048 			return (ECAPMODE);
2049 	}
2050 	memset(&domain, 0, sizeof(domain));
2051 	mask = malloc(domainsetsize, M_TEMP, M_WAITOK | M_ZERO);
2052 	error = copyin(maskp, mask, domainsetsize);
2053 	if (error)
2054 		goto out;
2055 	/*
2056 	 * Verify that no high bits are set.
2057 	 */
2058 	if (domainsetsize > sizeof(domainset_t)) {
2059 		char *end;
2060 		char *cp;
2061 
2062 		end = cp = (char *)&mask->__bits;
2063 		end += domainsetsize;
2064 		cp += sizeof(domainset_t);
2065 		while (cp != end)
2066 			if (*cp++ != 0) {
2067 				error = EINVAL;
2068 				goto out;
2069 			}
2070 
2071 	}
2072 	DOMAINSET_COPY(mask, &domain.ds_mask);
2073 	domain.ds_policy = policy;
2074 	if (policy <= DOMAINSET_POLICY_INVALID ||
2075 	    policy > DOMAINSET_POLICY_MAX)
2076 		return (EINVAL);
2077 
2078 	/* Translate preferred policy into a mask and fallback. */
2079 	if (policy == DOMAINSET_POLICY_PREFER) {
2080 		/* Only support a single preferred domain. */
2081 		if (DOMAINSET_COUNT(&domain.ds_mask) != 1)
2082 			return (EINVAL);
2083 		domain.ds_prefer = DOMAINSET_FFS(&domain.ds_mask) - 1;
2084 		/* This will be constrained by domainset_shadow(). */
2085 		DOMAINSET_FILL(&domain.ds_mask);
2086 	}
2087 
2088 	switch (level) {
2089 	case CPU_LEVEL_ROOT:
2090 	case CPU_LEVEL_CPUSET:
2091 		error = cpuset_which(which, id, &p, &ttd, &set);
2092 		if (error)
2093 			break;
2094 		switch (which) {
2095 		case CPU_WHICH_TID:
2096 		case CPU_WHICH_PID:
2097 			thread_lock(ttd);
2098 			set = cpuset_ref(ttd->td_cpuset);
2099 			thread_unlock(ttd);
2100 			PROC_UNLOCK(p);
2101 			break;
2102 		case CPU_WHICH_CPUSET:
2103 		case CPU_WHICH_JAIL:
2104 			break;
2105 		case CPU_WHICH_IRQ:
2106 		case CPU_WHICH_INTRHANDLER:
2107 		case CPU_WHICH_ITHREAD:
2108 		case CPU_WHICH_DOMAIN:
2109 			error = EINVAL;
2110 			goto out;
2111 		}
2112 		if (level == CPU_LEVEL_ROOT)
2113 			nset = cpuset_refroot(set);
2114 		else
2115 			nset = cpuset_refbase(set);
2116 		error = cpuset_modify_domain(nset, &domain);
2117 		cpuset_rel(nset);
2118 		cpuset_rel(set);
2119 		break;
2120 	case CPU_LEVEL_WHICH:
2121 		switch (which) {
2122 		case CPU_WHICH_TID:
2123 			error = _cpuset_setthread(id, NULL, &domain);
2124 			break;
2125 		case CPU_WHICH_PID:
2126 			error = cpuset_setproc(id, NULL, NULL, &domain);
2127 			break;
2128 		case CPU_WHICH_CPUSET:
2129 		case CPU_WHICH_JAIL:
2130 			error = cpuset_which(which, id, &p, &ttd, &set);
2131 			if (error == 0) {
2132 				error = cpuset_modify_domain(set, &domain);
2133 				cpuset_rel(set);
2134 			}
2135 			break;
2136 		case CPU_WHICH_IRQ:
2137 		case CPU_WHICH_INTRHANDLER:
2138 		case CPU_WHICH_ITHREAD:
2139 		default:
2140 			error = EINVAL;
2141 			break;
2142 		}
2143 		break;
2144 	default:
2145 		error = EINVAL;
2146 		break;
2147 	}
2148 out:
2149 	free(mask, M_TEMP);
2150 	return (error);
2151 }
2152 
2153 #ifdef DDB
2154 
2155 static void
2156 ddb_display_bitset(const struct bitset *set, int size)
2157 {
2158 	int bit, once;
2159 
2160 	for (once = 0, bit = 0; bit < size; bit++) {
2161 		if (CPU_ISSET(bit, set)) {
2162 			if (once == 0) {
2163 				db_printf("%d", bit);
2164 				once = 1;
2165 			} else
2166 				db_printf(",%d", bit);
2167 		}
2168 	}
2169 	if (once == 0)
2170 		db_printf("<none>");
2171 }
2172 
2173 void
2174 ddb_display_cpuset(const cpuset_t *set)
2175 {
2176 	ddb_display_bitset((const struct bitset *)set, CPU_SETSIZE);
2177 }
2178 
2179 static void
2180 ddb_display_domainset(const domainset_t *set)
2181 {
2182 	ddb_display_bitset((const struct bitset *)set, DOMAINSET_SETSIZE);
2183 }
2184 
2185 DB_SHOW_COMMAND(cpusets, db_show_cpusets)
2186 {
2187 	struct cpuset *set;
2188 
2189 	LIST_FOREACH(set, &cpuset_ids, cs_link) {
2190 		db_printf("set=%p id=%-6u ref=%-6d flags=0x%04x parent id=%d\n",
2191 		    set, set->cs_id, set->cs_ref, set->cs_flags,
2192 		    (set->cs_parent != NULL) ? set->cs_parent->cs_id : 0);
2193 		db_printf("  cpu mask=");
2194 		ddb_display_cpuset(&set->cs_mask);
2195 		db_printf("\n");
2196 		db_printf("  domain policy %d prefer %d mask=",
2197 		    set->cs_domain->ds_policy, set->cs_domain->ds_prefer);
2198 		ddb_display_domainset(&set->cs_domain->ds_mask);
2199 		db_printf("\n");
2200 		if (db_pager_quit)
2201 			break;
2202 	}
2203 }
2204 
2205 DB_SHOW_COMMAND(domainsets, db_show_domainsets)
2206 {
2207 	struct domainset *set;
2208 
2209 	LIST_FOREACH(set, &cpuset_domains, ds_link) {
2210 		db_printf("set=%p policy %d prefer %d cnt %d\n",
2211 		    set, set->ds_policy, set->ds_prefer, set->ds_cnt);
2212 		db_printf("  mask =");
2213 		ddb_display_domainset(&set->ds_mask);
2214 		db_printf("\n");
2215 	}
2216 }
2217 #endif /* DDB */
2218