xref: /freebsd/sys/dev/hwpmc/hwpmc_logging.c (revision 959826ca1bb0a42ddd624bf1803ae2957a3282f3)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2005-2007 Joseph Koshy
5  * Copyright (c) 2007 The FreeBSD Foundation
6  * Copyright (c) 2018 Matthew Macy
7  * All rights reserved.
8  *
9  * Portions of this software were developed by A. Joseph Koshy under
10  * sponsorship from the FreeBSD Foundation and Google, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  */
34 
35 /*
36  * Logging code for hwpmc(4)
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include <sys/param.h>
43 #include <sys/capsicum.h>
44 #include <sys/file.h>
45 #include <sys/kernel.h>
46 #include <sys/kthread.h>
47 #include <sys/lock.h>
48 #include <sys/module.h>
49 #include <sys/mutex.h>
50 #include <sys/pmc.h>
51 #include <sys/pmckern.h>
52 #include <sys/pmclog.h>
53 #include <sys/proc.h>
54 #include <sys/sched.h>
55 #include <sys/signalvar.h>
56 #include <sys/smp.h>
57 #include <sys/syscallsubr.h>
58 #include <sys/sysctl.h>
59 #include <sys/systm.h>
60 #include <sys/uio.h>
61 #include <sys/unistd.h>
62 #include <sys/vnode.h>
63 
64 #ifdef NUMA
65 #define NDOMAINS vm_ndomains
66 #define curdomain PCPU_GET(domain)
67 #else
68 #define NDOMAINS 1
69 #define curdomain 0
70 #define malloc_domain(size, type, domain, flags) malloc((size), (type), (flags))
71 #define free_domain(addr, type) free(addr, type)
72 #endif
73 
74 /*
75  * Sysctl tunables
76  */
77 
78 SYSCTL_DECL(_kern_hwpmc);
79 
80 /*
81  * kern.hwpmc.logbuffersize -- size of the per-cpu owner buffers.
82  */
83 
84 static int pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
85 #if (__FreeBSD_version < 1100000)
86 TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "logbuffersize", &pmclog_buffer_size);
87 #endif
88 SYSCTL_INT(_kern_hwpmc, OID_AUTO, logbuffersize, CTLFLAG_RDTUN,
89     &pmclog_buffer_size, 0, "size of log buffers in kilobytes");
90 
91 /*
92  * kern.hwpmc.nbuffer -- number of global log buffers
93  */
94 
95 static int pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
96 #if (__FreeBSD_version < 1100000)
97 TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "nbuffers", &pmc_nlogbuffers_pcpu);
98 #endif
99 SYSCTL_INT(_kern_hwpmc, OID_AUTO, nbuffers_pcpu, CTLFLAG_RDTUN,
100     &pmc_nlogbuffers_pcpu, 0, "number of log buffers per cpu");
101 
102 /*
103  * Global log buffer list and associated spin lock.
104  */
105 
106 static struct mtx pmc_kthread_mtx;	/* sleep lock */
107 
108 #define	PMCLOG_INIT_BUFFER_DESCRIPTOR(D, buf, domain) do {						\
109 		(D)->plb_fence = ((char *) (buf)) +	1024*pmclog_buffer_size;			\
110 		(D)->plb_base  = (D)->plb_ptr = ((char *) (buf));				\
111 		(D)->plb_domain = domain; \
112 	} while (0)
113 
114 #define	PMCLOG_RESET_BUFFER_DESCRIPTOR(D) do {			\
115 		(D)->plb_ptr  = (D)->plb_base; \
116 	} while (0)
117 
118 /*
119  * Log file record constructors.
120  */
121 #define	_PMCLOG_TO_HEADER(T,L)						\
122 	((PMCLOG_HEADER_MAGIC << 24) |					\
123 	 (PMCLOG_TYPE_ ## T << 16)   |					\
124 	 ((L) & 0xFFFF))
125 
126 /* reserve LEN bytes of space and initialize the entry header */
127 #define	_PMCLOG_RESERVE_SAFE(PO,TYPE,LEN,ACTION) do {			\
128 		uint32_t *_le;						\
129 		int _len = roundup((LEN), sizeof(uint32_t));	\
130 		if ((_le = pmclog_reserve((PO), _len)) == NULL) {	\
131 			ACTION;						\
132 		}							\
133 		*_le = _PMCLOG_TO_HEADER(TYPE,_len);			\
134 		_le += 3	/* skip over timestamp */
135 
136 /* reserve LEN bytes of space and initialize the entry header */
137 #define	_PMCLOG_RESERVE(PO,TYPE,LEN,ACTION) do {			\
138 		uint32_t *_le;						\
139 		int _len = roundup((LEN), sizeof(uint32_t));		\
140 		spinlock_enter();									\
141 		if ((_le = pmclog_reserve((PO), _len)) == NULL) {	\
142 			spinlock_exit();								\
143 			ACTION;											\
144 		}												\
145 		*_le = _PMCLOG_TO_HEADER(TYPE,_len);			\
146 		_le += 3	/* skip over timestamp */
147 
148 
149 #define	PMCLOG_RESERVE_SAFE(P,T,L)		_PMCLOG_RESERVE_SAFE(P,T,L,return)
150 #define	PMCLOG_RESERVE(P,T,L)		_PMCLOG_RESERVE(P,T,L,return)
151 #define	PMCLOG_RESERVE_WITH_ERROR(P,T,L) _PMCLOG_RESERVE(P,T,L,		\
152 	error=ENOMEM;goto error)
153 
154 #define	PMCLOG_EMIT32(V)	do { *_le++ = (V); } while (0)
155 #define	PMCLOG_EMIT64(V)	do { 					\
156 		*_le++ = (uint32_t) ((V) & 0xFFFFFFFF);			\
157 		*_le++ = (uint32_t) (((V) >> 32) & 0xFFFFFFFF);		\
158 	} while (0)
159 
160 
161 /* Emit a string.  Caution: does NOT update _le, so needs to be last */
162 #define	PMCLOG_EMITSTRING(S,L)	do { bcopy((S), _le, (L)); } while (0)
163 #define	PMCLOG_EMITNULLSTRING(L) do { bzero(_le, (L)); } while (0)
164 
165 #define	PMCLOG_DESPATCH_SAFE(PO)						\
166 	    pmclog_release((PO));						\
167 	} while (0)
168 
169 #define	PMCLOG_DESPATCH(PO)							\
170 	    pmclog_release((PO));						\
171 		spinlock_exit();							\
172 	} while (0)
173 
174 #define	PMCLOG_DESPATCH_SYNC(PO)						\
175 	    pmclog_schedule_io((PO));						\
176 		spinlock_exit();								\
177 		} while (0)
178 
179 
180 /*
181  * Assertions about the log file format.
182  */
183 
184 CTASSERT(sizeof(struct pmclog_callchain) == 8*4 +
185     PMC_CALLCHAIN_DEPTH_MAX*sizeof(uintfptr_t));
186 CTASSERT(sizeof(struct pmclog_closelog) == 4*4);
187 CTASSERT(sizeof(struct pmclog_dropnotify) == 4*4);
188 CTASSERT(sizeof(struct pmclog_map_in) == PATH_MAX +
189     4*4 + sizeof(uintfptr_t));
190 CTASSERT(offsetof(struct pmclog_map_in,pl_pathname) ==
191     4*4 + sizeof(uintfptr_t));
192 CTASSERT(sizeof(struct pmclog_map_out) == 4*4 + 2*sizeof(uintfptr_t));
193 CTASSERT(sizeof(struct pmclog_pmcallocate) == 6*4);
194 CTASSERT(sizeof(struct pmclog_pmcattach) == 6*4 + PATH_MAX);
195 CTASSERT(offsetof(struct pmclog_pmcattach,pl_pathname) == 6*4);
196 CTASSERT(sizeof(struct pmclog_pmcdetach) == 6*4);
197 CTASSERT(sizeof(struct pmclog_proccsw) == 6*4 + 8);
198 CTASSERT(sizeof(struct pmclog_procexec) == 6*4 + PATH_MAX +
199     sizeof(uintfptr_t));
200 CTASSERT(offsetof(struct pmclog_procexec,pl_pathname) == 6*4 +
201     sizeof(uintfptr_t));
202 CTASSERT(sizeof(struct pmclog_procexit) == 6*4 + 8);
203 CTASSERT(sizeof(struct pmclog_procfork) == 6*4);
204 CTASSERT(sizeof(struct pmclog_sysexit) == 4*4);
205 CTASSERT(sizeof(struct pmclog_userdata) == 4*4);
206 
207 /*
208  * Log buffer structure
209  */
210 
211 struct pmclog_buffer {
212 	TAILQ_ENTRY(pmclog_buffer) plb_next;
213 	char 		*plb_base;
214 	char		*plb_ptr;
215 	char 		*plb_fence;
216 	uint16_t	 plb_domain;
217 } __aligned(CACHE_LINE_SIZE);
218 
219 /*
220  * Prototypes
221  */
222 
223 static int pmclog_get_buffer(struct pmc_owner *po);
224 static void pmclog_loop(void *arg);
225 static void pmclog_release(struct pmc_owner *po);
226 static uint32_t *pmclog_reserve(struct pmc_owner *po, int length);
227 static void pmclog_schedule_io(struct pmc_owner *po);
228 static void pmclog_schedule_all(struct pmc_owner *po);
229 static void pmclog_stop_kthread(struct pmc_owner *po);
230 
231 /*
232  * Helper functions
233  */
234 
235 static inline void
236 pmc_plb_rele_unlocked(struct pmclog_buffer *plb)
237 {
238 	TAILQ_INSERT_HEAD(&pmc_dom_hdrs[plb->plb_domain]->pdbh_head, plb, plb_next);
239 }
240 
241 static inline void
242 pmc_plb_rele(struct pmclog_buffer *plb)
243 {
244 	mtx_lock_spin(&pmc_dom_hdrs[plb->plb_domain]->pdbh_mtx);
245 	pmc_plb_rele_unlocked(plb);
246 	mtx_unlock_spin(&pmc_dom_hdrs[plb->plb_domain]->pdbh_mtx);
247 }
248 
249 
250 /*
251  * Get a log buffer
252  */
253 
254 static int
255 pmclog_get_buffer(struct pmc_owner *po)
256 {
257 	struct pmclog_buffer *plb;
258 	int domain;
259 
260 	KASSERT(po->po_curbuf[curcpu] == NULL,
261 	    ("[pmclog,%d] po=%p current buffer still valid", __LINE__, po));
262 
263 	domain = curdomain;
264 	MPASS(pmc_dom_hdrs[domain]);
265 	mtx_lock_spin(&pmc_dom_hdrs[domain]->pdbh_mtx);
266 	if ((plb = TAILQ_FIRST(&pmc_dom_hdrs[domain]->pdbh_head)) != NULL)
267 		TAILQ_REMOVE(&pmc_dom_hdrs[domain]->pdbh_head, plb, plb_next);
268 	mtx_unlock_spin(&pmc_dom_hdrs[domain]->pdbh_mtx);
269 
270 	PMCDBG2(LOG,GTB,1, "po=%p plb=%p", po, plb);
271 
272 #ifdef	HWPMC_DEBUG
273 	if (plb)
274 		KASSERT(plb->plb_ptr == plb->plb_base &&
275 		    plb->plb_base < plb->plb_fence,
276 		    ("[pmclog,%d] po=%p buffer invariants: ptr=%p "
277 		    "base=%p fence=%p", __LINE__, po, plb->plb_ptr,
278 		    plb->plb_base, plb->plb_fence));
279 #endif
280 
281 	po->po_curbuf[curcpu] = plb;
282 
283 	/* update stats */
284 	counter_u64_add(pmc_stats.pm_buffer_requests, 1);
285 	if (plb == NULL)
286 		counter_u64_add(pmc_stats.pm_buffer_requests_failed, 1);
287 
288 	return (plb ? 0 : ENOMEM);
289 }
290 
291 struct pmclog_proc_init_args {
292 	struct proc *kthr;
293 	struct pmc_owner *po;
294 	bool exit;
295 	bool acted;
296 };
297 
298 int
299 pmclog_proc_create(struct thread *td, void **handlep)
300 {
301 	struct pmclog_proc_init_args *ia;
302 	int error;
303 
304 	ia = malloc(sizeof(*ia), M_TEMP, M_WAITOK | M_ZERO);
305 	error = kproc_create(pmclog_loop, ia, &ia->kthr,
306 	    RFHIGHPID, 0, "hwpmc: proc(%d)", td->td_proc->p_pid);
307 	if (error == 0)
308 		*handlep = ia;
309 	return (error);
310 }
311 
312 void
313 pmclog_proc_ignite(void *handle, struct pmc_owner *po)
314 {
315 	struct pmclog_proc_init_args *ia;
316 
317 	ia = handle;
318 	mtx_lock(&pmc_kthread_mtx);
319 	MPASS(!ia->acted);
320 	MPASS(ia->po == NULL);
321 	MPASS(!ia->exit);
322 	MPASS(ia->kthr != NULL);
323 	if (po == NULL) {
324 		ia->exit = true;
325 	} else {
326 		ia->po = po;
327 		KASSERT(po->po_kthread == NULL,
328 		    ("[pmclog,%d] po=%p kthread (%p) already present",
329 		    __LINE__, po, po->po_kthread));
330 		po->po_kthread = ia->kthr;
331 	}
332 	wakeup(ia);
333 	while (!ia->acted)
334 		msleep(ia, &pmc_kthread_mtx, PWAIT, "pmclogw", 0);
335 	mtx_unlock(&pmc_kthread_mtx);
336 	free(ia, M_TEMP);
337 }
338 
339 /*
340  * Log handler loop.
341  *
342  * This function is executed by each pmc owner's helper thread.
343  */
344 
345 static void
346 pmclog_loop(void *arg)
347 {
348 	struct pmclog_proc_init_args *ia;
349 	struct pmc_owner *po;
350 	struct pmclog_buffer *lb;
351 	struct proc *p;
352 	struct ucred *ownercred;
353 	struct ucred *mycred;
354 	struct thread *td;
355 	sigset_t unb;
356 	struct uio auio;
357 	struct iovec aiov;
358 	size_t nbytes;
359 	int error;
360 
361 	td = curthread;
362 
363 	SIGEMPTYSET(unb);
364 	SIGADDSET(unb, SIGHUP);
365 	(void)kern_sigprocmask(td, SIG_UNBLOCK, &unb, NULL, 0);
366 
367 	ia = arg;
368 	MPASS(ia->kthr == curproc);
369 	MPASS(!ia->acted);
370 	mtx_lock(&pmc_kthread_mtx);
371 	while (ia->po == NULL && !ia->exit)
372 		msleep(ia, &pmc_kthread_mtx, PWAIT, "pmclogi", 0);
373 	if (ia->exit) {
374 		ia->acted = true;
375 		wakeup(ia);
376 		mtx_unlock(&pmc_kthread_mtx);
377 		kproc_exit(0);
378 	}
379 	MPASS(ia->po != NULL);
380 	po = ia->po;
381 	ia->acted = true;
382 	wakeup(ia);
383 	mtx_unlock(&pmc_kthread_mtx);
384 	ia = NULL;
385 
386 	p = po->po_owner;
387 	mycred = td->td_ucred;
388 
389 	PROC_LOCK(p);
390 	ownercred = crhold(p->p_ucred);
391 	PROC_UNLOCK(p);
392 
393 	PMCDBG2(LOG,INI,1, "po=%p kt=%p", po, po->po_kthread);
394 	KASSERT(po->po_kthread == curthread->td_proc,
395 	    ("[pmclog,%d] proc mismatch po=%p po/kt=%p curproc=%p", __LINE__,
396 		po, po->po_kthread, curthread->td_proc));
397 
398 	lb = NULL;
399 
400 
401 	/*
402 	 * Loop waiting for I/O requests to be added to the owner
403 	 * struct's queue.  The loop is exited when the log file
404 	 * is deconfigured.
405 	 */
406 
407 	mtx_lock(&pmc_kthread_mtx);
408 
409 	for (;;) {
410 
411 		/* check if we've been asked to exit */
412 		if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
413 			break;
414 
415 		if (lb == NULL) { /* look for a fresh buffer to write */
416 			mtx_lock_spin(&po->po_mtx);
417 			if ((lb = TAILQ_FIRST(&po->po_logbuffers)) == NULL) {
418 				mtx_unlock_spin(&po->po_mtx);
419 
420 				/* No more buffers and shutdown required. */
421 				if (po->po_flags & PMC_PO_SHUTDOWN)
422 					break;
423 
424 				(void) msleep(po, &pmc_kthread_mtx, PWAIT,
425 				    "pmcloop", 0);
426 				continue;
427 			}
428 
429 			TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
430 			mtx_unlock_spin(&po->po_mtx);
431 		}
432 
433 		mtx_unlock(&pmc_kthread_mtx);
434 
435 		/* process the request */
436 		PMCDBG3(LOG,WRI,2, "po=%p base=%p ptr=%p", po,
437 		    lb->plb_base, lb->plb_ptr);
438 		/* change our thread's credentials before issuing the I/O */
439 
440 		aiov.iov_base = lb->plb_base;
441 		aiov.iov_len  = nbytes = lb->plb_ptr - lb->plb_base;
442 
443 		auio.uio_iov    = &aiov;
444 		auio.uio_iovcnt = 1;
445 		auio.uio_offset = -1;
446 		auio.uio_resid  = nbytes;
447 		auio.uio_rw     = UIO_WRITE;
448 		auio.uio_segflg = UIO_SYSSPACE;
449 		auio.uio_td     = td;
450 
451 		/* switch thread credentials -- see kern_ktrace.c */
452 		td->td_ucred = ownercred;
453 		error = fo_write(po->po_file, &auio, ownercred, 0, td);
454 		td->td_ucred = mycred;
455 
456 		if (error) {
457 			/* XXX some errors are recoverable */
458 			/* send a SIGIO to the owner and exit */
459 			PROC_LOCK(p);
460 			kern_psignal(p, SIGIO);
461 			PROC_UNLOCK(p);
462 
463 			mtx_lock(&pmc_kthread_mtx);
464 
465 			po->po_error = error; /* save for flush log */
466 
467 			PMCDBG2(LOG,WRI,2, "po=%p error=%d", po, error);
468 
469 			break;
470 		}
471 
472 		mtx_lock(&pmc_kthread_mtx);
473 
474 		/* put the used buffer back into the global pool */
475 		PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
476 
477 		pmc_plb_rele(lb);
478 		lb = NULL;
479 	}
480 
481 	wakeup_one(po->po_kthread);
482 	po->po_kthread = NULL;
483 
484 	mtx_unlock(&pmc_kthread_mtx);
485 
486 	/* return the current I/O buffer to the global pool */
487 	if (lb) {
488 		PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
489 
490 		pmc_plb_rele(lb);
491 	}
492 
493 	/*
494 	 * Exit this thread, signalling the waiter
495 	 */
496 
497 	crfree(ownercred);
498 
499 	kproc_exit(0);
500 }
501 
502 /*
503  * Release and log entry and schedule an I/O if needed.
504  */
505 
506 static void
507 pmclog_release(struct pmc_owner *po)
508 {
509 	struct pmclog_buffer *plb;
510 
511 	plb = po->po_curbuf[curcpu];
512 	KASSERT(plb->plb_ptr >= plb->plb_base,
513 	    ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
514 		po, plb->plb_ptr, plb->plb_base));
515 	KASSERT(plb->plb_ptr <= plb->plb_fence,
516 	    ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
517 		po, plb->plb_ptr, plb->plb_fence));
518 
519 	/* schedule an I/O if we've filled a buffer */
520 	if (plb->plb_ptr >= plb->plb_fence)
521 		pmclog_schedule_io(po);
522 
523 	PMCDBG1(LOG,REL,1, "po=%p", po);
524 }
525 
526 
527 /*
528  * Attempt to reserve 'length' bytes of space in an owner's log
529  * buffer.  The function returns a pointer to 'length' bytes of space
530  * if there was enough space or returns NULL if no space was
531  * available.  Non-null returns do so with the po mutex locked.  The
532  * caller must invoke pmclog_release() on the pmc owner structure
533  * when done.
534  */
535 
536 static uint32_t *
537 pmclog_reserve(struct pmc_owner *po, int length)
538 {
539 	uintptr_t newptr, oldptr;
540 	uint32_t *lh;
541 	struct timespec ts;
542 	struct pmclog_buffer *plb, **pplb;
543 
544 	PMCDBG2(LOG,ALL,1, "po=%p len=%d", po, length);
545 
546 	KASSERT(length % sizeof(uint32_t) == 0,
547 	    ("[pmclog,%d] length not a multiple of word size", __LINE__));
548 
549 	/* No more data when shutdown in progress. */
550 	if (po->po_flags & PMC_PO_SHUTDOWN)
551 		return (NULL);
552 
553 	pplb = &po->po_curbuf[curcpu];
554 	if (*pplb == NULL && pmclog_get_buffer(po) != 0)
555 		goto fail;
556 
557 	KASSERT(*pplb != NULL,
558 	    ("[pmclog,%d] po=%p no current buffer", __LINE__, po));
559 
560 	plb = *pplb;
561 	KASSERT(plb->plb_ptr >= plb->plb_base &&
562 	    plb->plb_ptr <= plb->plb_fence,
563 	    ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
564 		__LINE__, po, plb->plb_ptr, plb->plb_base,
565 		plb->plb_fence));
566 
567 	oldptr = (uintptr_t) plb->plb_ptr;
568 	newptr = oldptr + length;
569 
570 	KASSERT(oldptr != (uintptr_t) NULL,
571 	    ("[pmclog,%d] po=%p Null log buffer pointer", __LINE__, po));
572 
573 	/*
574 	 * If we have space in the current buffer, return a pointer to
575 	 * available space with the PO structure locked.
576 	 */
577 	if (newptr <= (uintptr_t) plb->plb_fence) {
578 		plb->plb_ptr = (char *) newptr;
579 		goto done;
580 	}
581 
582 	/*
583 	 * Otherwise, schedule the current buffer for output and get a
584 	 * fresh buffer.
585 	 */
586 	pmclog_schedule_io(po);
587 
588 	if (pmclog_get_buffer(po) != 0)
589 		goto fail;
590 
591 	plb = *pplb;
592 	KASSERT(plb != NULL,
593 	    ("[pmclog,%d] po=%p no current buffer", __LINE__, po));
594 
595 	KASSERT(plb->plb_ptr != NULL,
596 	    ("[pmclog,%d] null return from pmc_get_log_buffer", __LINE__));
597 
598 	KASSERT(plb->plb_ptr == plb->plb_base &&
599 	    plb->plb_ptr <= plb->plb_fence,
600 	    ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
601 		__LINE__, po, plb->plb_ptr, plb->plb_base,
602 		plb->plb_fence));
603 
604 	oldptr = (uintptr_t) plb->plb_ptr;
605 
606  done:
607 	lh = (uint32_t *) oldptr;
608 	lh++;				/* skip header */
609 	getnanotime(&ts);		/* fill in the timestamp */
610 	*lh++ = ts.tv_sec & 0xFFFFFFFF;
611 	*lh++ = ts.tv_nsec & 0xFFFFFFF;
612 	return ((uint32_t *) oldptr);
613  fail:
614 	return (NULL);
615 }
616 
617 /*
618  * Schedule an I/O.
619  *
620  * Transfer the current buffer to the helper kthread.
621  */
622 
623 static void
624 pmclog_schedule_io(struct pmc_owner *po)
625 {
626 	struct pmclog_buffer *plb;
627 
628 	plb = po->po_curbuf[curcpu];
629 	po->po_curbuf[curcpu] = NULL;
630 	KASSERT(plb != NULL,
631 	    ("[pmclog,%d] schedule_io with null buffer po=%p", __LINE__, po));
632 	KASSERT(plb->plb_ptr >= plb->plb_base,
633 	    ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
634 		po, plb->plb_ptr, plb->plb_base));
635 	KASSERT(plb->plb_ptr <= plb->plb_fence,
636 	    ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
637 		po, plb->plb_ptr, plb->plb_fence));
638 
639 	PMCDBG1(LOG,SIO, 1, "po=%p", po);
640 
641 	/*
642 	 * Add the current buffer to the tail of the buffer list and
643 	 * wakeup the helper.
644 	 */
645 	mtx_lock_spin(&po->po_mtx);
646 	TAILQ_INSERT_TAIL(&po->po_logbuffers, plb, plb_next);
647 	mtx_unlock_spin(&po->po_mtx);
648 	wakeup_one(po);
649 }
650 
651 /*
652  * Stop the helper kthread.
653  */
654 
655 static void
656 pmclog_stop_kthread(struct pmc_owner *po)
657 {
658 
659 	mtx_lock(&pmc_kthread_mtx);
660 	po->po_flags &= ~PMC_PO_OWNS_LOGFILE;
661 	if (po->po_kthread != NULL) {
662 		PROC_LOCK(po->po_kthread);
663 		kern_psignal(po->po_kthread, SIGHUP);
664 		PROC_UNLOCK(po->po_kthread);
665 	}
666 	wakeup_one(po);
667 	while (po->po_kthread)
668 		msleep(po->po_kthread, &pmc_kthread_mtx, PPAUSE, "pmckstp", 0);
669 	mtx_unlock(&pmc_kthread_mtx);
670 }
671 
672 /*
673  * Public functions
674  */
675 
676 /*
677  * Configure a log file for pmc owner 'po'.
678  *
679  * Parameter 'logfd' is a file handle referencing an open file in the
680  * owner process.  This file needs to have been opened for writing.
681  */
682 
683 int
684 pmclog_configure_log(struct pmc_mdep *md, struct pmc_owner *po, int logfd)
685 {
686 	struct proc *p;
687 	int error;
688 
689 	sx_assert(&pmc_sx, SA_XLOCKED);
690 	PMCDBG2(LOG,CFG,1, "config po=%p logfd=%d", po, logfd);
691 
692 	p = po->po_owner;
693 
694 	/* return EBUSY if a log file was already present */
695 	if (po->po_flags & PMC_PO_OWNS_LOGFILE)
696 		return (EBUSY);
697 
698 	KASSERT(po->po_file == NULL,
699 	    ("[pmclog,%d] po=%p file (%p) already present", __LINE__, po,
700 		po->po_file));
701 
702 	/* get a reference to the file state */
703 	error = fget_write(curthread, logfd, &cap_write_rights, &po->po_file);
704 	if (error)
705 		goto error;
706 
707 	/* mark process as owning a log file */
708 	po->po_flags |= PMC_PO_OWNS_LOGFILE;
709 
710 	/* mark process as using HWPMCs */
711 	PROC_LOCK(p);
712 	p->p_flag |= P_HWPMC;
713 	PROC_UNLOCK(p);
714 
715 	/* create a log initialization entry */
716 	PMCLOG_RESERVE_WITH_ERROR(po, INITIALIZE,
717 	    sizeof(struct pmclog_initialize));
718 	PMCLOG_EMIT32(PMC_VERSION);
719 	PMCLOG_EMIT32(md->pmd_cputype);
720 	PMCLOG_DESPATCH_SYNC(po);
721 
722 	return (0);
723 
724  error:
725 	KASSERT(po->po_kthread == NULL, ("[pmclog,%d] po=%p kthread not "
726 	    "stopped", __LINE__, po));
727 
728 	if (po->po_file)
729 		(void) fdrop(po->po_file, curthread);
730 	po->po_file  = NULL;	/* clear file and error state */
731 	po->po_error = 0;
732 	po->po_flags &= ~PMC_PO_OWNS_LOGFILE;
733 
734 	return (error);
735 }
736 
737 
738 /*
739  * De-configure a log file.  This will throw away any buffers queued
740  * for this owner process.
741  */
742 
743 int
744 pmclog_deconfigure_log(struct pmc_owner *po)
745 {
746 	int error;
747 	struct pmclog_buffer *lb;
748 
749 	PMCDBG1(LOG,CFG,1, "de-config po=%p", po);
750 
751 	if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
752 		return (EINVAL);
753 
754 	KASSERT(po->po_sscount == 0,
755 	    ("[pmclog,%d] po=%p still owning SS PMCs", __LINE__, po));
756 	KASSERT(po->po_file != NULL,
757 	    ("[pmclog,%d] po=%p no log file", __LINE__, po));
758 
759 	/* stop the kthread, this will reset the 'OWNS_LOGFILE' flag */
760 	pmclog_stop_kthread(po);
761 
762 	KASSERT(po->po_kthread == NULL,
763 	    ("[pmclog,%d] po=%p kthread not stopped", __LINE__, po));
764 
765 	/* return all queued log buffers to the global pool */
766 	while ((lb = TAILQ_FIRST(&po->po_logbuffers)) != NULL) {
767 		TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
768 		PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
769 		pmc_plb_rele(lb);
770 	}
771 	for (int i = 0; i < mp_ncpus; i++) {
772 		thread_lock(curthread);
773 		sched_bind(curthread, i);
774 		thread_unlock(curthread);
775 		/* return the 'current' buffer to the global pool */
776 		if ((lb = po->po_curbuf[curcpu]) != NULL) {
777 			PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
778 			pmc_plb_rele(lb);
779 		}
780 	}
781 	thread_lock(curthread);
782 	sched_unbind(curthread);
783 	thread_unlock(curthread);
784 
785 	/* drop a reference to the fd */
786 	if (po->po_file != NULL) {
787 		error = fdrop(po->po_file, curthread);
788 		po->po_file = NULL;
789 	} else
790 		error = 0;
791 	po->po_error = 0;
792 
793 	return (error);
794 }
795 
796 /*
797  * Flush a process' log buffer.
798  */
799 
800 int
801 pmclog_flush(struct pmc_owner *po)
802 {
803 	int error;
804 
805 	PMCDBG1(LOG,FLS,1, "po=%p", po);
806 
807 	/*
808 	 * If there is a pending error recorded by the logger thread,
809 	 * return that.
810 	 */
811 	if (po->po_error)
812 		return (po->po_error);
813 
814 	error = 0;
815 
816 	/*
817 	 * Check that we do have an active log file.
818 	 */
819 	mtx_lock(&pmc_kthread_mtx);
820 	if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) {
821 		error = EINVAL;
822 		goto error;
823 	}
824 
825 	pmclog_schedule_all(po);
826  error:
827 	mtx_unlock(&pmc_kthread_mtx);
828 
829 	return (error);
830 }
831 
832 static void
833 pmclog_schedule_one_cond(void *arg)
834 {
835 	struct pmc_owner *po = arg;
836 	struct pmclog_buffer *plb;
837 
838 	spinlock_enter();
839 	/* tell hardclock not to run again */
840 	if (PMC_CPU_HAS_SAMPLES(PCPU_GET(cpuid)))
841 		PMC_CALL_HOOK_UNLOCKED(curthread, PMC_FN_DO_SAMPLES, NULL);
842 	plb = po->po_curbuf[curcpu];
843 	if (plb && plb->plb_ptr != plb->plb_base)
844 		pmclog_schedule_io(po);
845 	spinlock_exit();
846 }
847 
848 static void
849 pmclog_schedule_all(struct pmc_owner *po)
850 {
851 	/*
852 	 * Schedule the current buffer if any and not empty.
853 	 */
854 	for (int i = 0; i < mp_ncpus; i++) {
855 		thread_lock(curthread);
856 		sched_bind(curthread, i);
857 		thread_unlock(curthread);
858 		pmclog_schedule_one_cond(po);
859 	}
860 	thread_lock(curthread);
861 	sched_unbind(curthread);
862 	thread_unlock(curthread);
863 }
864 
865 int
866 pmclog_close(struct pmc_owner *po)
867 {
868 
869 	PMCDBG1(LOG,CLO,1, "po=%p", po);
870 
871 	pmclog_process_closelog(po);
872 
873 	mtx_lock(&pmc_kthread_mtx);
874 	/*
875 	 * Initiate shutdown: no new data queued,
876 	 * thread will close file on last block.
877 	 */
878 	po->po_flags |= PMC_PO_SHUTDOWN;
879 	/* give time for all to see */
880 	DELAY(50);
881 
882 	/*
883 	 * Schedule the current buffer.
884 	 */
885 	pmclog_schedule_all(po);
886 	wakeup_one(po);
887 
888 	mtx_unlock(&pmc_kthread_mtx);
889 
890 	return (0);
891 }
892 
893 void
894 pmclog_process_callchain(struct pmc *pm, struct pmc_sample *ps)
895 {
896 	int n, recordlen;
897 	uint32_t flags;
898 	struct pmc_owner *po;
899 
900 	PMCDBG3(LOG,SAM,1,"pm=%p pid=%d n=%d", pm, ps->ps_pid,
901 	    ps->ps_nsamples);
902 
903 	recordlen = offsetof(struct pmclog_callchain, pl_pc) +
904 	    ps->ps_nsamples * sizeof(uintfptr_t);
905 	po = pm->pm_owner;
906 	flags = PMC_CALLCHAIN_TO_CPUFLAGS(ps->ps_cpu,ps->ps_flags);
907 	PMCLOG_RESERVE_SAFE(po, CALLCHAIN, recordlen);
908 	PMCLOG_EMIT32(ps->ps_pid);
909 	PMCLOG_EMIT32(ps->ps_tid);
910 	PMCLOG_EMIT32(pm->pm_id);
911 	PMCLOG_EMIT32(flags);
912 	/* unused for now */
913 	PMCLOG_EMIT32(0);
914 	for (n = 0; n < ps->ps_nsamples; n++)
915 		PMCLOG_EMITADDR(ps->ps_pc[n]);
916 	PMCLOG_DESPATCH_SAFE(po);
917 }
918 
919 void
920 pmclog_process_closelog(struct pmc_owner *po)
921 {
922 	PMCLOG_RESERVE(po,CLOSELOG,sizeof(struct pmclog_closelog));
923 	PMCLOG_DESPATCH_SYNC(po);
924 }
925 
926 void
927 pmclog_process_dropnotify(struct pmc_owner *po)
928 {
929 	PMCLOG_RESERVE(po,DROPNOTIFY,sizeof(struct pmclog_dropnotify));
930 	PMCLOG_DESPATCH(po);
931 }
932 
933 void
934 pmclog_process_map_in(struct pmc_owner *po, pid_t pid, uintfptr_t start,
935     const char *path)
936 {
937 	int pathlen, recordlen;
938 
939 	KASSERT(path != NULL, ("[pmclog,%d] map-in, null path", __LINE__));
940 
941 	pathlen = strlen(path) + 1;	/* #bytes for path name */
942 	recordlen = offsetof(struct pmclog_map_in, pl_pathname) +
943 	    pathlen;
944 
945 	PMCLOG_RESERVE(po, MAP_IN, recordlen);
946 	PMCLOG_EMIT32(pid);
947 	PMCLOG_EMITADDR(start);
948 	PMCLOG_EMITSTRING(path,pathlen);
949 	PMCLOG_DESPATCH(po);
950 }
951 
952 void
953 pmclog_process_map_out(struct pmc_owner *po, pid_t pid, uintfptr_t start,
954     uintfptr_t end)
955 {
956 	KASSERT(start <= end, ("[pmclog,%d] start > end", __LINE__));
957 
958 	PMCLOG_RESERVE(po, MAP_OUT, sizeof(struct pmclog_map_out));
959 	PMCLOG_EMIT32(pid);
960 	PMCLOG_EMITADDR(start);
961 	PMCLOG_EMITADDR(end);
962 	PMCLOG_DESPATCH(po);
963 }
964 
965 void
966 pmclog_process_pmcallocate(struct pmc *pm)
967 {
968 	struct pmc_owner *po;
969 	struct pmc_soft *ps;
970 
971 	po = pm->pm_owner;
972 
973 	PMCDBG1(LOG,ALL,1, "pm=%p", pm);
974 
975 	if (PMC_TO_CLASS(pm) == PMC_CLASS_SOFT) {
976 		PMCLOG_RESERVE(po, PMCALLOCATEDYN,
977 		    sizeof(struct pmclog_pmcallocatedyn));
978 		PMCLOG_EMIT32(pm->pm_id);
979 		PMCLOG_EMIT32(pm->pm_event);
980 		PMCLOG_EMIT32(pm->pm_flags);
981 		ps = pmc_soft_ev_acquire(pm->pm_event);
982 		if (ps != NULL)
983 			PMCLOG_EMITSTRING(ps->ps_ev.pm_ev_name,PMC_NAME_MAX);
984 		else
985 			PMCLOG_EMITNULLSTRING(PMC_NAME_MAX);
986 		pmc_soft_ev_release(ps);
987 		PMCLOG_DESPATCH_SYNC(po);
988 	} else {
989 		PMCLOG_RESERVE(po, PMCALLOCATE,
990 		    sizeof(struct pmclog_pmcallocate));
991 		PMCLOG_EMIT32(pm->pm_id);
992 		PMCLOG_EMIT32(pm->pm_event);
993 		PMCLOG_EMIT32(pm->pm_flags);
994 		PMCLOG_DESPATCH_SYNC(po);
995 	}
996 }
997 
998 void
999 pmclog_process_pmcattach(struct pmc *pm, pid_t pid, char *path)
1000 {
1001 	int pathlen, recordlen;
1002 	struct pmc_owner *po;
1003 
1004 	PMCDBG2(LOG,ATT,1,"pm=%p pid=%d", pm, pid);
1005 
1006 	po = pm->pm_owner;
1007 
1008 	pathlen = strlen(path) + 1;	/* #bytes for the string */
1009 	recordlen = offsetof(struct pmclog_pmcattach, pl_pathname) + pathlen;
1010 
1011 	PMCLOG_RESERVE(po, PMCATTACH, recordlen);
1012 	PMCLOG_EMIT32(pm->pm_id);
1013 	PMCLOG_EMIT32(pid);
1014 	PMCLOG_EMIT32(0);
1015 	PMCLOG_EMITSTRING(path, pathlen);
1016 	PMCLOG_DESPATCH_SYNC(po);
1017 }
1018 
1019 void
1020 pmclog_process_pmcdetach(struct pmc *pm, pid_t pid)
1021 {
1022 	struct pmc_owner *po;
1023 
1024 	PMCDBG2(LOG,ATT,1,"!pm=%p pid=%d", pm, pid);
1025 
1026 	po = pm->pm_owner;
1027 
1028 	PMCLOG_RESERVE(po, PMCDETACH, sizeof(struct pmclog_pmcdetach));
1029 	PMCLOG_EMIT32(pm->pm_id);
1030 	PMCLOG_EMIT32(pid);
1031 	PMCLOG_DESPATCH_SYNC(po);
1032 }
1033 
1034 /*
1035  * Log a context switch event to the log file.
1036  */
1037 
1038 void
1039 pmclog_process_proccsw(struct pmc *pm, struct pmc_process *pp, pmc_value_t v, struct thread *td)
1040 {
1041 	struct pmc_owner *po;
1042 
1043 	KASSERT(pm->pm_flags & PMC_F_LOG_PROCCSW,
1044 	    ("[pmclog,%d] log-process-csw called gratuitously", __LINE__));
1045 
1046 	PMCDBG3(LOG,SWO,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
1047 	    v);
1048 
1049 	po = pm->pm_owner;
1050 
1051 	PMCLOG_RESERVE(po, PROCCSW, sizeof(struct pmclog_proccsw));
1052 	PMCLOG_EMIT32(pm->pm_id);
1053 	PMCLOG_EMIT64(v);
1054 	PMCLOG_EMIT32(pp->pp_proc->p_pid);
1055 	PMCLOG_EMIT32(td->td_tid);
1056 	PMCLOG_DESPATCH(po);
1057 }
1058 
1059 void
1060 pmclog_process_procexec(struct pmc_owner *po, pmc_id_t pmid, pid_t pid,
1061     uintfptr_t startaddr, char *path)
1062 {
1063 	int pathlen, recordlen;
1064 
1065 	PMCDBG3(LOG,EXC,1,"po=%p pid=%d path=\"%s\"", po, pid, path);
1066 
1067 	pathlen   = strlen(path) + 1;	/* #bytes for the path */
1068 	recordlen = offsetof(struct pmclog_procexec, pl_pathname) + pathlen;
1069 
1070 	PMCLOG_RESERVE(po, PROCEXEC, recordlen);
1071 	PMCLOG_EMIT32(pid);
1072 	PMCLOG_EMIT32(pmid);
1073 	PMCLOG_EMIT32(0);
1074 	PMCLOG_EMITADDR(startaddr);
1075 	PMCLOG_EMITSTRING(path,pathlen);
1076 	PMCLOG_DESPATCH(po);
1077 }
1078 
1079 /*
1080  * Log a process exit event (and accumulated pmc value) to the log file.
1081  */
1082 
1083 void
1084 pmclog_process_procexit(struct pmc *pm, struct pmc_process *pp)
1085 {
1086 	int ri;
1087 	struct pmc_owner *po;
1088 
1089 	ri = PMC_TO_ROWINDEX(pm);
1090 	PMCDBG3(LOG,EXT,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
1091 	    pp->pp_pmcs[ri].pp_pmcval);
1092 
1093 	po = pm->pm_owner;
1094 
1095 	PMCLOG_RESERVE(po, PROCEXIT, sizeof(struct pmclog_procexit));
1096 	PMCLOG_EMIT32(pm->pm_id);
1097 	PMCLOG_EMIT32(pp->pp_proc->p_pid);
1098 	PMCLOG_EMIT32(0);
1099 	PMCLOG_EMIT64(pp->pp_pmcs[ri].pp_pmcval);
1100 	PMCLOG_DESPATCH(po);
1101 }
1102 
1103 /*
1104  * Log a fork event.
1105  */
1106 
1107 void
1108 pmclog_process_procfork(struct pmc_owner *po, pid_t oldpid, pid_t newpid)
1109 {
1110 	PMCLOG_RESERVE(po, PROCFORK, sizeof(struct pmclog_procfork));
1111 	PMCLOG_EMIT32(oldpid);
1112 	PMCLOG_EMIT32(newpid);
1113 	PMCLOG_DESPATCH(po);
1114 }
1115 
1116 /*
1117  * Log a process exit event of the form suitable for system-wide PMCs.
1118  */
1119 
1120 void
1121 pmclog_process_sysexit(struct pmc_owner *po, pid_t pid)
1122 {
1123 	PMCLOG_RESERVE(po, SYSEXIT, sizeof(struct pmclog_sysexit));
1124 	PMCLOG_EMIT32(pid);
1125 	PMCLOG_DESPATCH(po);
1126 }
1127 
1128 /*
1129  * Write a user log entry.
1130  */
1131 
1132 int
1133 pmclog_process_userlog(struct pmc_owner *po, struct pmc_op_writelog *wl)
1134 {
1135 	int error;
1136 
1137 	PMCDBG2(LOG,WRI,1, "writelog po=%p ud=0x%x", po, wl->pm_userdata);
1138 
1139 	error = 0;
1140 
1141 	PMCLOG_RESERVE_WITH_ERROR(po, USERDATA,
1142 	    sizeof(struct pmclog_userdata));
1143 	PMCLOG_EMIT32(wl->pm_userdata);
1144 	PMCLOG_DESPATCH(po);
1145 
1146  error:
1147 	return (error);
1148 }
1149 
1150 /*
1151  * Initialization.
1152  *
1153  * Create a pool of log buffers and initialize mutexes.
1154  */
1155 
1156 void
1157 pmclog_initialize()
1158 {
1159 	int domain;
1160 	struct pmclog_buffer *plb;
1161 
1162 	if (pmclog_buffer_size <= 0 || pmclog_buffer_size > 16*1024) {
1163 		(void) printf("hwpmc: tunable logbuffersize=%d must be "
1164 					  "greater than zero and less than or equal to 16MB.\n",
1165 					  pmclog_buffer_size);
1166 		pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
1167 	}
1168 
1169 	if (pmc_nlogbuffers_pcpu <= 0) {
1170 		(void) printf("hwpmc: tunable nlogbuffers=%d must be greater "
1171 					  "than zero.\n", pmc_nlogbuffers_pcpu);
1172 		pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
1173 	}
1174 	if (pmc_nlogbuffers_pcpu*pmclog_buffer_size > 32*1024) {
1175 		(void) printf("hwpmc: memory allocated pcpu must be less than 32MB (is %dK).\n",
1176 					  pmc_nlogbuffers_pcpu*pmclog_buffer_size);
1177 		pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
1178 		pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
1179 	}
1180 	for (domain = 0; domain < NDOMAINS; domain++) {
1181 		int ncpus = pmc_dom_hdrs[domain]->pdbh_ncpus;
1182 		int total = ncpus*pmc_nlogbuffers_pcpu;
1183 
1184 		plb = malloc_domain(sizeof(struct pmclog_buffer)*total, M_PMC, domain, M_WAITOK|M_ZERO);
1185 		pmc_dom_hdrs[domain]->pdbh_plbs = plb;
1186 		for (int i = 0; i < total; i++, plb++) {
1187 			void *buf;
1188 
1189 			buf = malloc_domain(1024 * pmclog_buffer_size, M_PMC, domain,
1190 								M_WAITOK|M_ZERO);
1191 			PMCLOG_INIT_BUFFER_DESCRIPTOR(plb, buf, domain);
1192 			pmc_plb_rele_unlocked(plb);
1193 		}
1194 	}
1195 	mtx_init(&pmc_kthread_mtx, "pmc-kthread", "pmc-sleep", MTX_DEF);
1196 }
1197 
1198 /*
1199  * Shutdown logging.
1200  *
1201  * Destroy mutexes and release memory back the to free pool.
1202  */
1203 
1204 void
1205 pmclog_shutdown()
1206 {
1207 	struct pmclog_buffer *plb;
1208 	int domain;
1209 
1210 	mtx_destroy(&pmc_kthread_mtx);
1211 
1212 	for (domain = 0; domain < NDOMAINS; domain++) {
1213 		while ((plb = TAILQ_FIRST(&pmc_dom_hdrs[domain]->pdbh_head)) != NULL) {
1214 			TAILQ_REMOVE(&pmc_dom_hdrs[domain]->pdbh_head, plb, plb_next);
1215 			free(plb->plb_base, M_PMC);
1216 		}
1217 		free(pmc_dom_hdrs[domain]->pdbh_plbs, M_PMC);
1218 	}
1219 }
1220