xref: /freebsd/sys/kern/kern_racct.c (revision 1f4bcc459a76b7aa664f3fd557684cd0ba6da352)
1 /*-
2  * Copyright (c) 2010 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Edward Tomasz Napierala under sponsorship
6  * from the FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_sched.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/eventhandler.h>
40 #include <sys/jail.h>
41 #include <sys/kernel.h>
42 #include <sys/kthread.h>
43 #include <sys/lock.h>
44 #include <sys/loginclass.h>
45 #include <sys/malloc.h>
46 #include <sys/mutex.h>
47 #include <sys/proc.h>
48 #include <sys/racct.h>
49 #include <sys/resourcevar.h>
50 #include <sys/sbuf.h>
51 #include <sys/sched.h>
52 #include <sys/sdt.h>
53 #include <sys/smp.h>
54 #include <sys/sx.h>
55 #include <sys/sysctl.h>
56 #include <sys/sysent.h>
57 #include <sys/sysproto.h>
58 #include <sys/umtx.h>
59 #include <machine/smp.h>
60 
61 #ifdef RCTL
62 #include <sys/rctl.h>
63 #endif
64 
65 #ifdef RACCT
66 
67 FEATURE(racct, "Resource Accounting");
68 
69 /*
70  * Do not block processes that have their %cpu usage <= pcpu_threshold.
71  */
72 static int pcpu_threshold = 1;
73 #ifdef RACCT_DEFAULT_TO_DISABLED
74 int racct_enable = 0;
75 #else
76 int racct_enable = 1;
77 #endif
78 
79 SYSCTL_NODE(_kern, OID_AUTO, racct, CTLFLAG_RW, 0, "Resource Accounting");
80 SYSCTL_UINT(_kern_racct, OID_AUTO, enable, CTLFLAG_RDTUN, &racct_enable,
81     0, "Enable RACCT/RCTL");
82 SYSCTL_UINT(_kern_racct, OID_AUTO, pcpu_threshold, CTLFLAG_RW, &pcpu_threshold,
83     0, "Processes with higher %cpu usage than this value can be throttled.");
84 
85 /*
86  * How many seconds it takes to use the scheduler %cpu calculations.  When a
87  * process starts, we compute its %cpu usage by dividing its runtime by the
88  * process wall clock time.  After RACCT_PCPU_SECS pass, we use the value
89  * provided by the scheduler.
90  */
91 #define RACCT_PCPU_SECS		3
92 
93 static struct mtx racct_lock;
94 MTX_SYSINIT(racct_lock, &racct_lock, "racct lock", MTX_DEF);
95 
96 static uma_zone_t racct_zone;
97 
98 static void racct_sub_racct(struct racct *dest, const struct racct *src);
99 static void racct_sub_cred_locked(struct ucred *cred, int resource,
100 		uint64_t amount);
101 static void racct_add_cred_locked(struct ucred *cred, int resource,
102 		uint64_t amount);
103 
104 SDT_PROVIDER_DEFINE(racct);
105 SDT_PROBE_DEFINE3(racct, , rusage, add,
106     "struct proc *", "int", "uint64_t");
107 SDT_PROBE_DEFINE3(racct, , rusage, add__failure,
108     "struct proc *", "int", "uint64_t");
109 SDT_PROBE_DEFINE3(racct, , rusage, add__cred,
110     "struct ucred *", "int", "uint64_t");
111 SDT_PROBE_DEFINE3(racct, , rusage, add__force,
112     "struct proc *", "int", "uint64_t");
113 SDT_PROBE_DEFINE3(racct, , rusage, set,
114     "struct proc *", "int", "uint64_t");
115 SDT_PROBE_DEFINE3(racct, , rusage, set__failure,
116     "struct proc *", "int", "uint64_t");
117 SDT_PROBE_DEFINE3(racct, , rusage, sub,
118     "struct proc *", "int", "uint64_t");
119 SDT_PROBE_DEFINE3(racct, , rusage, sub__cred,
120     "struct ucred *", "int", "uint64_t");
121 SDT_PROBE_DEFINE1(racct, , racct, create,
122     "struct racct *");
123 SDT_PROBE_DEFINE1(racct, , racct, destroy,
124     "struct racct *");
125 SDT_PROBE_DEFINE2(racct, , racct, join,
126     "struct racct *", "struct racct *");
127 SDT_PROBE_DEFINE2(racct, , racct, join__failure,
128     "struct racct *", "struct racct *");
129 SDT_PROBE_DEFINE2(racct, , racct, leave,
130     "struct racct *", "struct racct *");
131 
132 int racct_types[] = {
133 	[RACCT_CPU] =
134 		RACCT_IN_MILLIONS,
135 	[RACCT_DATA] =
136 		RACCT_RECLAIMABLE | RACCT_INHERITABLE | RACCT_DENIABLE,
137 	[RACCT_STACK] =
138 		RACCT_RECLAIMABLE | RACCT_INHERITABLE | RACCT_DENIABLE,
139 	[RACCT_CORE] =
140 		RACCT_DENIABLE,
141 	[RACCT_RSS] =
142 		RACCT_RECLAIMABLE,
143 	[RACCT_MEMLOCK] =
144 		RACCT_RECLAIMABLE | RACCT_DENIABLE,
145 	[RACCT_NPROC] =
146 		RACCT_RECLAIMABLE | RACCT_DENIABLE,
147 	[RACCT_NOFILE] =
148 		RACCT_RECLAIMABLE | RACCT_INHERITABLE | RACCT_DENIABLE,
149 	[RACCT_VMEM] =
150 		RACCT_RECLAIMABLE | RACCT_INHERITABLE | RACCT_DENIABLE,
151 	[RACCT_NPTS] =
152 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
153 	[RACCT_SWAP] =
154 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
155 	[RACCT_NTHR] =
156 		RACCT_RECLAIMABLE | RACCT_DENIABLE,
157 	[RACCT_MSGQQUEUED] =
158 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
159 	[RACCT_MSGQSIZE] =
160 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
161 	[RACCT_NMSGQ] =
162 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
163 	[RACCT_NSEM] =
164 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
165 	[RACCT_NSEMOP] =
166 		RACCT_RECLAIMABLE | RACCT_INHERITABLE | RACCT_DENIABLE,
167 	[RACCT_NSHM] =
168 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
169 	[RACCT_SHMSIZE] =
170 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
171 	[RACCT_WALLCLOCK] =
172 		RACCT_IN_MILLIONS,
173 	[RACCT_PCTCPU] =
174 		RACCT_DECAYING | RACCT_DENIABLE | RACCT_IN_MILLIONS };
175 
176 static const fixpt_t RACCT_DECAY_FACTOR = 0.3 * FSCALE;
177 
178 #ifdef SCHED_4BSD
179 /*
180  * Contains intermediate values for %cpu calculations to avoid using floating
181  * point in the kernel.
182  * ccpu_exp[k] = FSCALE * (ccpu/FSCALE)^k = FSCALE * exp(-k/20)
183  * It is needed only for the 4BSD scheduler, because in ULE, the ccpu equals to
184  * zero so the calculations are more straightforward.
185  */
186 fixpt_t ccpu_exp[] = {
187 	[0] = FSCALE * 1,
188 	[1] = FSCALE * 0.95122942450071400909,
189 	[2] = FSCALE * 0.90483741803595957316,
190 	[3] = FSCALE * 0.86070797642505780722,
191 	[4] = FSCALE * 0.81873075307798185866,
192 	[5] = FSCALE * 0.77880078307140486824,
193 	[6] = FSCALE * 0.74081822068171786606,
194 	[7] = FSCALE * 0.70468808971871343435,
195 	[8] = FSCALE * 0.67032004603563930074,
196 	[9] = FSCALE * 0.63762815162177329314,
197 	[10] = FSCALE * 0.60653065971263342360,
198 	[11] = FSCALE * 0.57694981038048669531,
199 	[12] = FSCALE * 0.54881163609402643262,
200 	[13] = FSCALE * 0.52204577676101604789,
201 	[14] = FSCALE * 0.49658530379140951470,
202 	[15] = FSCALE * 0.47236655274101470713,
203 	[16] = FSCALE * 0.44932896411722159143,
204 	[17] = FSCALE * 0.42741493194872666992,
205 	[18] = FSCALE * 0.40656965974059911188,
206 	[19] = FSCALE * 0.38674102345450120691,
207 	[20] = FSCALE * 0.36787944117144232159,
208 	[21] = FSCALE * 0.34993774911115535467,
209 	[22] = FSCALE * 0.33287108369807955328,
210 	[23] = FSCALE * 0.31663676937905321821,
211 	[24] = FSCALE * 0.30119421191220209664,
212 	[25] = FSCALE * 0.28650479686019010032,
213 	[26] = FSCALE * 0.27253179303401260312,
214 	[27] = FSCALE * 0.25924026064589150757,
215 	[28] = FSCALE * 0.24659696394160647693,
216 	[29] = FSCALE * 0.23457028809379765313,
217 	[30] = FSCALE * 0.22313016014842982893,
218 	[31] = FSCALE * 0.21224797382674305771,
219 	[32] = FSCALE * 0.20189651799465540848,
220 	[33] = FSCALE * 0.19204990862075411423,
221 	[34] = FSCALE * 0.18268352405273465022,
222 	[35] = FSCALE * 0.17377394345044512668,
223 	[36] = FSCALE * 0.16529888822158653829,
224 	[37] = FSCALE * 0.15723716631362761621,
225 	[38] = FSCALE * 0.14956861922263505264,
226 	[39] = FSCALE * 0.14227407158651357185,
227 	[40] = FSCALE * 0.13533528323661269189,
228 	[41] = FSCALE * 0.12873490358780421886,
229 	[42] = FSCALE * 0.12245642825298191021,
230 	[43] = FSCALE * 0.11648415777349695786,
231 	[44] = FSCALE * 0.11080315836233388333,
232 	[45] = FSCALE * 0.10539922456186433678,
233 	[46] = FSCALE * 0.10025884372280373372,
234 	[47] = FSCALE * 0.09536916221554961888,
235 	[48] = FSCALE * 0.09071795328941250337,
236 	[49] = FSCALE * 0.08629358649937051097,
237 	[50] = FSCALE * 0.08208499862389879516,
238 	[51] = FSCALE * 0.07808166600115315231,
239 	[52] = FSCALE * 0.07427357821433388042,
240 	[53] = FSCALE * 0.07065121306042958674,
241 	[54] = FSCALE * 0.06720551273974976512,
242 	[55] = FSCALE * 0.06392786120670757270,
243 	[56] = FSCALE * 0.06081006262521796499,
244 	[57] = FSCALE * 0.05784432087483846296,
245 	[58] = FSCALE * 0.05502322005640722902,
246 	[59] = FSCALE * 0.05233970594843239308,
247 	[60] = FSCALE * 0.04978706836786394297,
248 	[61] = FSCALE * 0.04735892439114092119,
249 	[62] = FSCALE * 0.04504920239355780606,
250 	[63] = FSCALE * 0.04285212686704017991,
251 	[64] = FSCALE * 0.04076220397836621516,
252 	[65] = FSCALE * 0.03877420783172200988,
253 	[66] = FSCALE * 0.03688316740124000544,
254 	[67] = FSCALE * 0.03508435410084502588,
255 	[68] = FSCALE * 0.03337326996032607948,
256 	[69] = FSCALE * 0.03174563637806794323,
257 	[70] = FSCALE * 0.03019738342231850073,
258 	[71] = FSCALE * 0.02872463965423942912,
259 	[72] = FSCALE * 0.02732372244729256080,
260 	[73] = FSCALE * 0.02599112877875534358,
261 	[74] = FSCALE * 0.02472352647033939120,
262 	[75] = FSCALE * 0.02351774585600910823,
263 	[76] = FSCALE * 0.02237077185616559577,
264 	[77] = FSCALE * 0.02127973643837716938,
265 	[78] = FSCALE * 0.02024191144580438847,
266 	[79] = FSCALE * 0.01925470177538692429,
267 	[80] = FSCALE * 0.01831563888873418029,
268 	[81] = FSCALE * 0.01742237463949351138,
269 	[82] = FSCALE * 0.01657267540176124754,
270 	[83] = FSCALE * 0.01576441648485449082,
271 	[84] = FSCALE * 0.01499557682047770621,
272 	[85] = FSCALE * 0.01426423390899925527,
273 	[86] = FSCALE * 0.01356855901220093175,
274 	[87] = FSCALE * 0.01290681258047986886,
275 	[88] = FSCALE * 0.01227733990306844117,
276 	[89] = FSCALE * 0.01167856697039544521,
277 	[90] = FSCALE * 0.01110899653824230649,
278 	[91] = FSCALE * 0.01056720438385265337,
279 	[92] = FSCALE * 0.01005183574463358164,
280 	[93] = FSCALE * 0.00956160193054350793,
281 	[94] = FSCALE * 0.00909527710169581709,
282 	[95] = FSCALE * 0.00865169520312063417,
283 	[96] = FSCALE * 0.00822974704902002884,
284 	[97] = FSCALE * 0.00782837754922577143,
285 	[98] = FSCALE * 0.00744658307092434051,
286 	[99] = FSCALE * 0.00708340892905212004,
287 	[100] = FSCALE * 0.00673794699908546709,
288 	[101] = FSCALE * 0.00640933344625638184,
289 	[102] = FSCALE * 0.00609674656551563610,
290 	[103] = FSCALE * 0.00579940472684214321,
291 	[104] = FSCALE * 0.00551656442076077241,
292 	[105] = FSCALE * 0.00524751839918138427,
293 	[106] = FSCALE * 0.00499159390691021621,
294 	[107] = FSCALE * 0.00474815099941147558,
295 	[108] = FSCALE * 0.00451658094261266798,
296 	[109] = FSCALE * 0.00429630469075234057,
297 	[110] = FSCALE * 0.00408677143846406699,
298 };
299 #endif
300 
301 #define	CCPU_EXP_MAX	110
302 
303 /*
304  * This function is analogical to the getpcpu() function in the ps(1) command.
305  * They should both calculate in the same way so that the racct %cpu
306  * calculations are consistent with the values showed by the ps(1) tool.
307  * The calculations are more complex in the 4BSD scheduler because of the value
308  * of the ccpu variable.  In ULE it is defined to be zero which saves us some
309  * work.
310  */
311 static uint64_t
312 racct_getpcpu(struct proc *p, u_int pcpu)
313 {
314 	u_int swtime;
315 #ifdef SCHED_4BSD
316 	fixpt_t pctcpu, pctcpu_next;
317 #endif
318 #ifdef SMP
319 	struct pcpu *pc;
320 	int found;
321 #endif
322 	fixpt_t p_pctcpu;
323 	struct thread *td;
324 
325 	ASSERT_RACCT_ENABLED();
326 
327 	/*
328 	 * If the process is swapped out, we count its %cpu usage as zero.
329 	 * This behaviour is consistent with the userland ps(1) tool.
330 	 */
331 	if ((p->p_flag & P_INMEM) == 0)
332 		return (0);
333 	swtime = (ticks - p->p_swtick) / hz;
334 
335 	/*
336 	 * For short-lived processes, the sched_pctcpu() returns small
337 	 * values even for cpu intensive processes.  Therefore we use
338 	 * our own estimate in this case.
339 	 */
340 	if (swtime < RACCT_PCPU_SECS)
341 		return (pcpu);
342 
343 	p_pctcpu = 0;
344 	FOREACH_THREAD_IN_PROC(p, td) {
345 		if (td == PCPU_GET(idlethread))
346 			continue;
347 #ifdef SMP
348 		found = 0;
349 		STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
350 			if (td == pc->pc_idlethread) {
351 				found = 1;
352 				break;
353 			}
354 		}
355 		if (found)
356 			continue;
357 #endif
358 		thread_lock(td);
359 #ifdef SCHED_4BSD
360 		pctcpu = sched_pctcpu(td);
361 		/* Count also the yet unfinished second. */
362 		pctcpu_next = (pctcpu * ccpu_exp[1]) >> FSHIFT;
363 		pctcpu_next += sched_pctcpu_delta(td);
364 		p_pctcpu += max(pctcpu, pctcpu_next);
365 #else
366 		/*
367 		 * In ULE the %cpu statistics are updated on every
368 		 * sched_pctcpu() call.  So special calculations to
369 		 * account for the latest (unfinished) second are
370 		 * not needed.
371 		 */
372 		p_pctcpu += sched_pctcpu(td);
373 #endif
374 		thread_unlock(td);
375 	}
376 
377 #ifdef SCHED_4BSD
378 	if (swtime <= CCPU_EXP_MAX)
379 		return ((100 * (uint64_t)p_pctcpu * 1000000) /
380 		    (FSCALE - ccpu_exp[swtime]));
381 #endif
382 
383 	return ((100 * (uint64_t)p_pctcpu * 1000000) / FSCALE);
384 }
385 
386 static void
387 racct_add_racct(struct racct *dest, const struct racct *src)
388 {
389 	int i;
390 
391 	ASSERT_RACCT_ENABLED();
392 	mtx_assert(&racct_lock, MA_OWNED);
393 
394 	/*
395 	 * Update resource usage in dest.
396 	 */
397 	for (i = 0; i <= RACCT_MAX; i++) {
398 		KASSERT(dest->r_resources[i] >= 0,
399 		    ("%s: resource %d propagation meltdown: dest < 0",
400 		    __func__, i));
401 		KASSERT(src->r_resources[i] >= 0,
402 		    ("%s: resource %d propagation meltdown: src < 0",
403 		    __func__, i));
404 		dest->r_resources[i] += src->r_resources[i];
405 	}
406 }
407 
408 static void
409 racct_sub_racct(struct racct *dest, const struct racct *src)
410 {
411 	int i;
412 
413 	ASSERT_RACCT_ENABLED();
414 	mtx_assert(&racct_lock, MA_OWNED);
415 
416 	/*
417 	 * Update resource usage in dest.
418 	 */
419 	for (i = 0; i <= RACCT_MAX; i++) {
420 		if (!RACCT_IS_SLOPPY(i) && !RACCT_IS_DECAYING(i)) {
421 			KASSERT(dest->r_resources[i] >= 0,
422 			    ("%s: resource %d propagation meltdown: dest < 0",
423 			    __func__, i));
424 			KASSERT(src->r_resources[i] >= 0,
425 			    ("%s: resource %d propagation meltdown: src < 0",
426 			    __func__, i));
427 			KASSERT(src->r_resources[i] <= dest->r_resources[i],
428 			    ("%s: resource %d propagation meltdown: src > dest",
429 			    __func__, i));
430 		}
431 		if (RACCT_CAN_DROP(i)) {
432 			dest->r_resources[i] -= src->r_resources[i];
433 			if (dest->r_resources[i] < 0) {
434 				KASSERT(RACCT_IS_SLOPPY(i) ||
435 				    RACCT_IS_DECAYING(i),
436 				    ("%s: resource %d usage < 0", __func__, i));
437 				dest->r_resources[i] = 0;
438 			}
439 		}
440 	}
441 }
442 
443 void
444 racct_create(struct racct **racctp)
445 {
446 
447 	if (!racct_enable)
448 		return;
449 
450 	SDT_PROBE1(racct, , racct, create, racctp);
451 
452 	KASSERT(*racctp == NULL, ("racct already allocated"));
453 
454 	*racctp = uma_zalloc(racct_zone, M_WAITOK | M_ZERO);
455 }
456 
457 static void
458 racct_destroy_locked(struct racct **racctp)
459 {
460 	int i;
461 	struct racct *racct;
462 
463 	ASSERT_RACCT_ENABLED();
464 
465 	SDT_PROBE1(racct, , racct, destroy, racctp);
466 
467 	mtx_assert(&racct_lock, MA_OWNED);
468 	KASSERT(racctp != NULL, ("NULL racctp"));
469 	KASSERT(*racctp != NULL, ("NULL racct"));
470 
471 	racct = *racctp;
472 
473 	for (i = 0; i <= RACCT_MAX; i++) {
474 		if (RACCT_IS_SLOPPY(i))
475 			continue;
476 		if (!RACCT_IS_RECLAIMABLE(i))
477 			continue;
478 		KASSERT(racct->r_resources[i] == 0,
479 		    ("destroying non-empty racct: "
480 		    "%ju allocated for resource %d\n",
481 		    racct->r_resources[i], i));
482 	}
483 	uma_zfree(racct_zone, racct);
484 	*racctp = NULL;
485 }
486 
487 void
488 racct_destroy(struct racct **racct)
489 {
490 
491 	if (!racct_enable)
492 		return;
493 
494 	mtx_lock(&racct_lock);
495 	racct_destroy_locked(racct);
496 	mtx_unlock(&racct_lock);
497 }
498 
499 /*
500  * Increase consumption of 'resource' by 'amount' for 'racct',
501  * but not its parents.  Differently from other cases, 'amount' here
502  * may be less than zero.
503  */
504 static void
505 racct_adjust_resource(struct racct *racct, int resource,
506     int64_t amount)
507 {
508 
509 	ASSERT_RACCT_ENABLED();
510 	mtx_assert(&racct_lock, MA_OWNED);
511 	KASSERT(racct != NULL, ("NULL racct"));
512 
513 	racct->r_resources[resource] += amount;
514 	if (racct->r_resources[resource] < 0) {
515 		KASSERT(RACCT_IS_SLOPPY(resource) || RACCT_IS_DECAYING(resource),
516 		    ("%s: resource %d usage < 0", __func__, resource));
517 		racct->r_resources[resource] = 0;
518 	}
519 
520 	/*
521 	 * There are some cases where the racct %cpu resource would grow
522 	 * beyond 100% per core.  For example in racct_proc_exit() we add
523 	 * the process %cpu usage to the ucred racct containers.  If too
524 	 * many processes terminated in a short time span, the ucred %cpu
525 	 * resource could grow too much.  Also, the 4BSD scheduler sometimes
526 	 * returns for a thread more than 100% cpu usage. So we set a sane
527 	 * boundary here to 100% * the maxumum number of CPUs.
528 	 */
529 	if ((resource == RACCT_PCTCPU) &&
530 	    (racct->r_resources[RACCT_PCTCPU] > 100 * 1000000 * (int64_t)MAXCPU))
531 		racct->r_resources[RACCT_PCTCPU] = 100 * 1000000 * (int64_t)MAXCPU;
532 }
533 
534 static int
535 racct_add_locked(struct proc *p, int resource, uint64_t amount)
536 {
537 #ifdef RCTL
538 	int error;
539 #endif
540 
541 	ASSERT_RACCT_ENABLED();
542 
543 	SDT_PROBE3(racct, , rusage, add, p, resource, amount);
544 
545 	/*
546 	 * We need proc lock to dereference p->p_ucred.
547 	 */
548 	PROC_LOCK_ASSERT(p, MA_OWNED);
549 
550 #ifdef RCTL
551 	error = rctl_enforce(p, resource, amount);
552 	if (error && RACCT_IS_DENIABLE(resource)) {
553 		SDT_PROBE3(racct, , rusage, add__failure, p, resource, amount);
554 		return (error);
555 	}
556 #endif
557 	racct_adjust_resource(p->p_racct, resource, amount);
558 	racct_add_cred_locked(p->p_ucred, resource, amount);
559 
560 	return (0);
561 }
562 
563 /*
564  * Increase allocation of 'resource' by 'amount' for process 'p'.
565  * Return 0 if it's below limits, or errno, if it's not.
566  */
567 int
568 racct_add(struct proc *p, int resource, uint64_t amount)
569 {
570 	int error;
571 
572 	if (!racct_enable)
573 		return (0);
574 
575 	mtx_lock(&racct_lock);
576 	error = racct_add_locked(p, resource, amount);
577 	mtx_unlock(&racct_lock);
578 	return (error);
579 }
580 
581 static void
582 racct_add_cred_locked(struct ucred *cred, int resource, uint64_t amount)
583 {
584 	struct prison *pr;
585 
586 	ASSERT_RACCT_ENABLED();
587 
588 	SDT_PROBE3(racct, , rusage, add__cred, cred, resource, amount);
589 
590 	racct_adjust_resource(cred->cr_ruidinfo->ui_racct, resource, amount);
591 	for (pr = cred->cr_prison; pr != NULL; pr = pr->pr_parent)
592 		racct_adjust_resource(pr->pr_prison_racct->prr_racct, resource,
593 		    amount);
594 	racct_adjust_resource(cred->cr_loginclass->lc_racct, resource, amount);
595 }
596 
597 /*
598  * Increase allocation of 'resource' by 'amount' for credential 'cred'.
599  * Doesn't check for limits and never fails.
600  *
601  * XXX: Shouldn't this ever return an error?
602  */
603 void
604 racct_add_cred(struct ucred *cred, int resource, uint64_t amount)
605 {
606 
607 	if (!racct_enable)
608 		return;
609 
610 	mtx_lock(&racct_lock);
611 	racct_add_cred_locked(cred, resource, amount);
612 	mtx_unlock(&racct_lock);
613 }
614 
615 /*
616  * Increase allocation of 'resource' by 'amount' for process 'p'.
617  * Doesn't check for limits and never fails.
618  */
619 void
620 racct_add_force(struct proc *p, int resource, uint64_t amount)
621 {
622 
623 	if (!racct_enable)
624 		return;
625 
626 	SDT_PROBE3(racct, , rusage, add__force, p, resource, amount);
627 
628 	/*
629 	 * We need proc lock to dereference p->p_ucred.
630 	 */
631 	PROC_LOCK_ASSERT(p, MA_OWNED);
632 
633 	mtx_lock(&racct_lock);
634 	racct_adjust_resource(p->p_racct, resource, amount);
635 	racct_add_cred_locked(p->p_ucred, resource, amount);
636 	mtx_unlock(&racct_lock);
637 }
638 
639 static int
640 racct_set_locked(struct proc *p, int resource, uint64_t amount)
641 {
642 	int64_t old_amount, decayed_amount;
643 	int64_t diff_proc, diff_cred;
644 #ifdef RCTL
645 	int error;
646 #endif
647 
648 	ASSERT_RACCT_ENABLED();
649 
650 	SDT_PROBE3(racct, , rusage, set, p, resource, amount);
651 
652 	/*
653 	 * We need proc lock to dereference p->p_ucred.
654 	 */
655 	PROC_LOCK_ASSERT(p, MA_OWNED);
656 
657 	old_amount = p->p_racct->r_resources[resource];
658 	/*
659 	 * The diffs may be negative.
660 	 */
661 	diff_proc = amount - old_amount;
662 	if (RACCT_IS_DECAYING(resource)) {
663 		/*
664 		 * Resources in per-credential racct containers may decay.
665 		 * If this is the case, we need to calculate the difference
666 		 * between the new amount and the proportional value of the
667 		 * old amount that has decayed in the ucred racct containers.
668 		 */
669 		decayed_amount = old_amount * RACCT_DECAY_FACTOR / FSCALE;
670 		diff_cred = amount - decayed_amount;
671 	} else
672 		diff_cred = diff_proc;
673 #ifdef notyet
674 	KASSERT(diff_proc >= 0 || RACCT_CAN_DROP(resource),
675 	    ("%s: usage of non-droppable resource %d dropping", __func__,
676 	     resource));
677 #endif
678 #ifdef RCTL
679 	if (diff_proc > 0) {
680 		error = rctl_enforce(p, resource, diff_proc);
681 		if (error && RACCT_IS_DENIABLE(resource)) {
682 			SDT_PROBE3(racct, , rusage, set__failure, p, resource,
683 			    amount);
684 			return (error);
685 		}
686 	}
687 #endif
688 	racct_adjust_resource(p->p_racct, resource, diff_proc);
689 	if (diff_cred > 0)
690 		racct_add_cred_locked(p->p_ucred, resource, diff_cred);
691 	else if (diff_cred < 0)
692 		racct_sub_cred_locked(p->p_ucred, resource, -diff_cred);
693 
694 	return (0);
695 }
696 
697 /*
698  * Set allocation of 'resource' to 'amount' for process 'p'.
699  * Return 0 if it's below limits, or errno, if it's not.
700  *
701  * Note that decreasing the allocation always returns 0,
702  * even if it's above the limit.
703  */
704 int
705 racct_set(struct proc *p, int resource, uint64_t amount)
706 {
707 	int error;
708 
709 	if (!racct_enable)
710 		return (0);
711 
712 	mtx_lock(&racct_lock);
713 	error = racct_set_locked(p, resource, amount);
714 	mtx_unlock(&racct_lock);
715 	return (error);
716 }
717 
718 static void
719 racct_set_force_locked(struct proc *p, int resource, uint64_t amount)
720 {
721 	int64_t old_amount, decayed_amount;
722 	int64_t diff_proc, diff_cred;
723 
724 	ASSERT_RACCT_ENABLED();
725 
726 	SDT_PROBE3(racct, , rusage, set, p, resource, amount);
727 
728 	/*
729 	 * We need proc lock to dereference p->p_ucred.
730 	 */
731 	PROC_LOCK_ASSERT(p, MA_OWNED);
732 
733 	old_amount = p->p_racct->r_resources[resource];
734 	/*
735 	 * The diffs may be negative.
736 	 */
737 	diff_proc = amount - old_amount;
738 	if (RACCT_IS_DECAYING(resource)) {
739 		/*
740 		 * Resources in per-credential racct containers may decay.
741 		 * If this is the case, we need to calculate the difference
742 		 * between the new amount and the proportional value of the
743 		 * old amount that has decayed in the ucred racct containers.
744 		 */
745 		decayed_amount = old_amount * RACCT_DECAY_FACTOR / FSCALE;
746 		diff_cred = amount - decayed_amount;
747 	} else
748 		diff_cred = diff_proc;
749 
750 	racct_adjust_resource(p->p_racct, resource, diff_proc);
751 	if (diff_cred > 0)
752 		racct_add_cred_locked(p->p_ucred, resource, diff_cred);
753 	else if (diff_cred < 0)
754 		racct_sub_cred_locked(p->p_ucred, resource, -diff_cred);
755 }
756 
757 void
758 racct_set_force(struct proc *p, int resource, uint64_t amount)
759 {
760 
761 	if (!racct_enable)
762 		return;
763 
764 	mtx_lock(&racct_lock);
765 	racct_set_force_locked(p, resource, amount);
766 	mtx_unlock(&racct_lock);
767 }
768 
769 /*
770  * Returns amount of 'resource' the process 'p' can keep allocated.
771  * Allocating more than that would be denied, unless the resource
772  * is marked undeniable.  Amount of already allocated resource does
773  * not matter.
774  */
775 uint64_t
776 racct_get_limit(struct proc *p, int resource)
777 {
778 
779 	if (!racct_enable)
780 		return (UINT64_MAX);
781 
782 #ifdef RCTL
783 	return (rctl_get_limit(p, resource));
784 #else
785 	return (UINT64_MAX);
786 #endif
787 }
788 
789 /*
790  * Returns amount of 'resource' the process 'p' can keep allocated.
791  * Allocating more than that would be denied, unless the resource
792  * is marked undeniable.  Amount of already allocated resource does
793  * matter.
794  */
795 uint64_t
796 racct_get_available(struct proc *p, int resource)
797 {
798 
799 	if (!racct_enable)
800 		return (UINT64_MAX);
801 
802 #ifdef RCTL
803 	return (rctl_get_available(p, resource));
804 #else
805 	return (UINT64_MAX);
806 #endif
807 }
808 
809 /*
810  * Returns amount of the %cpu resource that process 'p' can add to its %cpu
811  * utilization.  Adding more than that would lead to the process being
812  * throttled.
813  */
814 static int64_t
815 racct_pcpu_available(struct proc *p)
816 {
817 
818 	ASSERT_RACCT_ENABLED();
819 
820 #ifdef RCTL
821 	return (rctl_pcpu_available(p));
822 #else
823 	return (INT64_MAX);
824 #endif
825 }
826 
827 /*
828  * Decrease allocation of 'resource' by 'amount' for process 'p'.
829  */
830 void
831 racct_sub(struct proc *p, int resource, uint64_t amount)
832 {
833 
834 	if (!racct_enable)
835 		return;
836 
837 	SDT_PROBE3(racct, , rusage, sub, p, resource, amount);
838 
839 	/*
840 	 * We need proc lock to dereference p->p_ucred.
841 	 */
842 	PROC_LOCK_ASSERT(p, MA_OWNED);
843 	KASSERT(RACCT_CAN_DROP(resource),
844 	    ("%s: called for non-droppable resource %d", __func__, resource));
845 
846 	mtx_lock(&racct_lock);
847 	KASSERT(amount <= p->p_racct->r_resources[resource],
848 	    ("%s: freeing %ju of resource %d, which is more "
849 	     "than allocated %jd for %s (pid %d)", __func__, amount, resource,
850 	    (intmax_t)p->p_racct->r_resources[resource], p->p_comm, p->p_pid));
851 
852 	racct_adjust_resource(p->p_racct, resource, -amount);
853 	racct_sub_cred_locked(p->p_ucred, resource, amount);
854 	mtx_unlock(&racct_lock);
855 }
856 
857 static void
858 racct_sub_cred_locked(struct ucred *cred, int resource, uint64_t amount)
859 {
860 	struct prison *pr;
861 
862 	ASSERT_RACCT_ENABLED();
863 
864 	SDT_PROBE3(racct, , rusage, sub__cred, cred, resource, amount);
865 
866 #ifdef notyet
867 	KASSERT(RACCT_CAN_DROP(resource),
868 	    ("%s: called for resource %d which can not drop", __func__,
869 	     resource));
870 #endif
871 
872 	racct_adjust_resource(cred->cr_ruidinfo->ui_racct, resource, -amount);
873 	for (pr = cred->cr_prison; pr != NULL; pr = pr->pr_parent)
874 		racct_adjust_resource(pr->pr_prison_racct->prr_racct, resource,
875 		    -amount);
876 	racct_adjust_resource(cred->cr_loginclass->lc_racct, resource, -amount);
877 }
878 
879 /*
880  * Decrease allocation of 'resource' by 'amount' for credential 'cred'.
881  */
882 void
883 racct_sub_cred(struct ucred *cred, int resource, uint64_t amount)
884 {
885 
886 	if (!racct_enable)
887 		return;
888 
889 	mtx_lock(&racct_lock);
890 	racct_sub_cred_locked(cred, resource, amount);
891 	mtx_unlock(&racct_lock);
892 }
893 
894 /*
895  * Inherit resource usage information from the parent process.
896  */
897 int
898 racct_proc_fork(struct proc *parent, struct proc *child)
899 {
900 	int i, error = 0;
901 
902 	if (!racct_enable)
903 		return (0);
904 
905 	/*
906 	 * Create racct for the child process.
907 	 */
908 	racct_create(&child->p_racct);
909 
910 	PROC_LOCK(parent);
911 	PROC_LOCK(child);
912 	mtx_lock(&racct_lock);
913 
914 #ifdef RCTL
915 	error = rctl_proc_fork(parent, child);
916 	if (error != 0)
917 		goto out;
918 #endif
919 
920 	/* Init process cpu time. */
921 	child->p_prev_runtime = 0;
922 	child->p_throttled = 0;
923 
924 	/*
925 	 * Inherit resource usage.
926 	 */
927 	for (i = 0; i <= RACCT_MAX; i++) {
928 		if (parent->p_racct->r_resources[i] == 0 ||
929 		    !RACCT_IS_INHERITABLE(i))
930 			continue;
931 
932 		error = racct_set_locked(child, i,
933 		    parent->p_racct->r_resources[i]);
934 		if (error != 0)
935 			goto out;
936 	}
937 
938 	error = racct_add_locked(child, RACCT_NPROC, 1);
939 	error += racct_add_locked(child, RACCT_NTHR, 1);
940 
941 out:
942 	mtx_unlock(&racct_lock);
943 	PROC_UNLOCK(child);
944 	PROC_UNLOCK(parent);
945 
946 	if (error != 0)
947 		racct_proc_exit(child);
948 
949 	return (error);
950 }
951 
952 /*
953  * Called at the end of fork1(), to handle rules that require the process
954  * to be fully initialized.
955  */
956 void
957 racct_proc_fork_done(struct proc *child)
958 {
959 
960 #ifdef RCTL
961 	if (!racct_enable)
962 		return;
963 
964 	PROC_LOCK(child);
965 	mtx_lock(&racct_lock);
966 	rctl_enforce(child, RACCT_NPROC, 0);
967 	rctl_enforce(child, RACCT_NTHR, 0);
968 	mtx_unlock(&racct_lock);
969 	PROC_UNLOCK(child);
970 #endif
971 }
972 
973 void
974 racct_proc_exit(struct proc *p)
975 {
976 	int i;
977 	uint64_t runtime;
978 	struct timeval wallclock;
979 	uint64_t pct_estimate, pct;
980 
981 	if (!racct_enable)
982 		return;
983 
984 	PROC_LOCK(p);
985 	/*
986 	 * We don't need to calculate rux, proc_reap() has already done this.
987 	 */
988 	runtime = cputick2usec(p->p_rux.rux_runtime);
989 #ifdef notyet
990 	KASSERT(runtime >= p->p_prev_runtime, ("runtime < p_prev_runtime"));
991 #else
992 	if (runtime < p->p_prev_runtime)
993 		runtime = p->p_prev_runtime;
994 #endif
995 	microuptime(&wallclock);
996 	timevalsub(&wallclock, &p->p_stats->p_start);
997 	if (wallclock.tv_sec > 0 || wallclock.tv_usec > 0) {
998 		pct_estimate = (1000000 * runtime * 100) /
999 		    ((uint64_t)wallclock.tv_sec * 1000000 +
1000 		    wallclock.tv_usec);
1001 	} else
1002 		pct_estimate = 0;
1003 	pct = racct_getpcpu(p, pct_estimate);
1004 
1005 	mtx_lock(&racct_lock);
1006 	racct_set_locked(p, RACCT_CPU, runtime);
1007 	racct_add_cred_locked(p->p_ucred, RACCT_PCTCPU, pct);
1008 
1009 	for (i = 0; i <= RACCT_MAX; i++) {
1010 		if (p->p_racct->r_resources[i] == 0)
1011 			continue;
1012 	    	if (!RACCT_IS_RECLAIMABLE(i))
1013 			continue;
1014 		racct_set_locked(p, i, 0);
1015 	}
1016 
1017 	mtx_unlock(&racct_lock);
1018 	PROC_UNLOCK(p);
1019 
1020 #ifdef RCTL
1021 	rctl_racct_release(p->p_racct);
1022 #endif
1023 	racct_destroy(&p->p_racct);
1024 }
1025 
1026 /*
1027  * Called after credentials change, to move resource utilisation
1028  * between raccts.
1029  */
1030 void
1031 racct_proc_ucred_changed(struct proc *p, struct ucred *oldcred,
1032     struct ucred *newcred)
1033 {
1034 	struct uidinfo *olduip, *newuip;
1035 	struct loginclass *oldlc, *newlc;
1036 	struct prison *oldpr, *newpr, *pr;
1037 
1038 	if (!racct_enable)
1039 		return;
1040 
1041 	PROC_LOCK_ASSERT(p, MA_NOTOWNED);
1042 
1043 	newuip = newcred->cr_ruidinfo;
1044 	olduip = oldcred->cr_ruidinfo;
1045 	newlc = newcred->cr_loginclass;
1046 	oldlc = oldcred->cr_loginclass;
1047 	newpr = newcred->cr_prison;
1048 	oldpr = oldcred->cr_prison;
1049 
1050 	mtx_lock(&racct_lock);
1051 	if (newuip != olduip) {
1052 		racct_sub_racct(olduip->ui_racct, p->p_racct);
1053 		racct_add_racct(newuip->ui_racct, p->p_racct);
1054 	}
1055 	if (newlc != oldlc) {
1056 		racct_sub_racct(oldlc->lc_racct, p->p_racct);
1057 		racct_add_racct(newlc->lc_racct, p->p_racct);
1058 	}
1059 	if (newpr != oldpr) {
1060 		for (pr = oldpr; pr != NULL; pr = pr->pr_parent)
1061 			racct_sub_racct(pr->pr_prison_racct->prr_racct,
1062 			    p->p_racct);
1063 		for (pr = newpr; pr != NULL; pr = pr->pr_parent)
1064 			racct_add_racct(pr->pr_prison_racct->prr_racct,
1065 			    p->p_racct);
1066 	}
1067 	mtx_unlock(&racct_lock);
1068 
1069 #ifdef RCTL
1070 	rctl_proc_ucred_changed(p, newcred);
1071 #endif
1072 }
1073 
1074 void
1075 racct_move(struct racct *dest, struct racct *src)
1076 {
1077 
1078 	ASSERT_RACCT_ENABLED();
1079 
1080 	mtx_lock(&racct_lock);
1081 
1082 	racct_add_racct(dest, src);
1083 	racct_sub_racct(src, src);
1084 
1085 	mtx_unlock(&racct_lock);
1086 }
1087 
1088 static void
1089 racct_proc_throttle(struct proc *p)
1090 {
1091 	struct thread *td;
1092 #ifdef SMP
1093 	int cpuid;
1094 #endif
1095 
1096 	ASSERT_RACCT_ENABLED();
1097 	PROC_LOCK_ASSERT(p, MA_OWNED);
1098 
1099 	/*
1100 	 * Do not block kernel processes.  Also do not block processes with
1101 	 * low %cpu utilization to improve interactivity.
1102 	 */
1103 	if (((p->p_flag & (P_SYSTEM | P_KTHREAD)) != 0) ||
1104 	    (p->p_racct->r_resources[RACCT_PCTCPU] <= pcpu_threshold))
1105 		return;
1106 	p->p_throttled = 1;
1107 
1108 	FOREACH_THREAD_IN_PROC(p, td) {
1109 		thread_lock(td);
1110 		switch (td->td_state) {
1111 		case TDS_RUNQ:
1112 			/*
1113 			 * If the thread is on the scheduler run-queue, we can
1114 			 * not just remove it from there.  So we set the flag
1115 			 * TDF_NEEDRESCHED for the thread, so that once it is
1116 			 * running, it is taken off the cpu as soon as possible.
1117 			 */
1118 			td->td_flags |= TDF_NEEDRESCHED;
1119 			break;
1120 		case TDS_RUNNING:
1121 			/*
1122 			 * If the thread is running, we request a context
1123 			 * switch for it by setting the TDF_NEEDRESCHED flag.
1124 			 */
1125 			td->td_flags |= TDF_NEEDRESCHED;
1126 #ifdef SMP
1127 			cpuid = td->td_oncpu;
1128 			if ((cpuid != NOCPU) && (td != curthread))
1129 				ipi_cpu(cpuid, IPI_AST);
1130 #endif
1131 			break;
1132 		default:
1133 			break;
1134 		}
1135 		thread_unlock(td);
1136 	}
1137 }
1138 
1139 static void
1140 racct_proc_wakeup(struct proc *p)
1141 {
1142 
1143 	ASSERT_RACCT_ENABLED();
1144 
1145 	PROC_LOCK_ASSERT(p, MA_OWNED);
1146 
1147 	if (p->p_throttled) {
1148 		p->p_throttled = 0;
1149 		wakeup(p->p_racct);
1150 	}
1151 }
1152 
1153 static void
1154 racct_decay_resource(struct racct *racct, void * res, void* dummy)
1155 {
1156 	int resource;
1157 	int64_t r_old, r_new;
1158 
1159 	ASSERT_RACCT_ENABLED();
1160 	mtx_assert(&racct_lock, MA_OWNED);
1161 
1162 	resource = *(int *)res;
1163 	r_old = racct->r_resources[resource];
1164 
1165 	/* If there is nothing to decay, just exit. */
1166 	if (r_old <= 0)
1167 		return;
1168 
1169 	r_new = r_old * RACCT_DECAY_FACTOR / FSCALE;
1170 	racct->r_resources[resource] = r_new;
1171 }
1172 
1173 static void
1174 racct_decay_pre(void)
1175 {
1176 
1177 	mtx_lock(&racct_lock);
1178 }
1179 
1180 static void
1181 racct_decay_post(void)
1182 {
1183 
1184 	mtx_unlock(&racct_lock);
1185 }
1186 
1187 static void
1188 racct_decay(int resource)
1189 {
1190 
1191 	ASSERT_RACCT_ENABLED();
1192 
1193 	ui_racct_foreach(racct_decay_resource, racct_decay_pre,
1194 	    racct_decay_post, &resource, NULL);
1195 	loginclass_racct_foreach(racct_decay_resource, racct_decay_pre,
1196 	    racct_decay_post, &resource, NULL);
1197 	prison_racct_foreach(racct_decay_resource, racct_decay_pre,
1198 	    racct_decay_post, &resource, NULL);
1199 }
1200 
1201 static void
1202 racctd(void)
1203 {
1204 	struct thread *td;
1205 	struct proc *p;
1206 	struct timeval wallclock;
1207 	uint64_t runtime;
1208 	uint64_t pct, pct_estimate;
1209 
1210 	ASSERT_RACCT_ENABLED();
1211 
1212 	for (;;) {
1213 		racct_decay(RACCT_PCTCPU);
1214 
1215 		sx_slock(&allproc_lock);
1216 
1217 		LIST_FOREACH(p, &zombproc, p_list) {
1218 			PROC_LOCK(p);
1219 			racct_set(p, RACCT_PCTCPU, 0);
1220 			PROC_UNLOCK(p);
1221 		}
1222 
1223 		FOREACH_PROC_IN_SYSTEM(p) {
1224 			PROC_LOCK(p);
1225 			if (p->p_state != PRS_NORMAL) {
1226 				PROC_UNLOCK(p);
1227 				continue;
1228 			}
1229 
1230 			microuptime(&wallclock);
1231 			timevalsub(&wallclock, &p->p_stats->p_start);
1232 			PROC_STATLOCK(p);
1233 			FOREACH_THREAD_IN_PROC(p, td)
1234 				ruxagg(p, td);
1235 			runtime = cputick2usec(p->p_rux.rux_runtime);
1236 			PROC_STATUNLOCK(p);
1237 #ifdef notyet
1238 			KASSERT(runtime >= p->p_prev_runtime,
1239 			    ("runtime < p_prev_runtime"));
1240 #else
1241 			if (runtime < p->p_prev_runtime)
1242 				runtime = p->p_prev_runtime;
1243 #endif
1244 			p->p_prev_runtime = runtime;
1245 			if (wallclock.tv_sec > 0 || wallclock.tv_usec > 0) {
1246 				pct_estimate = (1000000 * runtime * 100) /
1247 				    ((uint64_t)wallclock.tv_sec * 1000000 +
1248 				    wallclock.tv_usec);
1249 			} else
1250 				pct_estimate = 0;
1251 			pct = racct_getpcpu(p, pct_estimate);
1252 			mtx_lock(&racct_lock);
1253 			racct_set_force_locked(p, RACCT_PCTCPU, pct);
1254 			racct_set_locked(p, RACCT_CPU, runtime);
1255 			racct_set_locked(p, RACCT_WALLCLOCK,
1256 			    (uint64_t)wallclock.tv_sec * 1000000 +
1257 			    wallclock.tv_usec);
1258 			mtx_unlock(&racct_lock);
1259 			PROC_UNLOCK(p);
1260 		}
1261 
1262 		/*
1263 		 * To ensure that processes are throttled in a fair way, we need
1264 		 * to iterate over all processes again and check the limits
1265 		 * for %cpu resource only after ucred racct containers have been
1266 		 * properly filled.
1267 		 */
1268 		FOREACH_PROC_IN_SYSTEM(p) {
1269 			PROC_LOCK(p);
1270 			if (p->p_state != PRS_NORMAL) {
1271 				PROC_UNLOCK(p);
1272 				continue;
1273 			}
1274 
1275 			if (racct_pcpu_available(p) <= 0)
1276 				racct_proc_throttle(p);
1277 			else if (p->p_throttled)
1278 				racct_proc_wakeup(p);
1279 			PROC_UNLOCK(p);
1280 		}
1281 		sx_sunlock(&allproc_lock);
1282 		pause("-", hz);
1283 	}
1284 }
1285 
1286 static struct kproc_desc racctd_kp = {
1287 	"racctd",
1288 	racctd,
1289 	NULL
1290 };
1291 
1292 static void
1293 racctd_init(void)
1294 {
1295 	if (!racct_enable)
1296 		return;
1297 
1298 	kproc_start(&racctd_kp);
1299 }
1300 SYSINIT(racctd, SI_SUB_RACCTD, SI_ORDER_FIRST, racctd_init, NULL);
1301 
1302 static void
1303 racct_init(void)
1304 {
1305 	if (!racct_enable)
1306 		return;
1307 
1308 	racct_zone = uma_zcreate("racct", sizeof(struct racct),
1309 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
1310 	/*
1311 	 * XXX: Move this somewhere.
1312 	 */
1313 	prison0.pr_prison_racct = prison_racct_find("0");
1314 }
1315 SYSINIT(racct, SI_SUB_RACCT, SI_ORDER_FIRST, racct_init, NULL);
1316 
1317 #endif /* !RACCT */
1318