xref: /freebsd/sys/dev/hwpmc/hwpmc_logging.c (revision 2449fa9c4d8e60cca863396dc3c7d67cbc16359f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
40 #include <sys/capsicum.h>
41 #include <sys/domainset.h>
42 #include <sys/file.h>
43 #include <sys/kernel.h>
44 #include <sys/kthread.h>
45 #include <sys/lock.h>
46 #include <sys/module.h>
47 #include <sys/mutex.h>
48 #include <sys/pmc.h>
49 #include <sys/pmckern.h>
50 #include <sys/pmclog.h>
51 #include <sys/proc.h>
52 #include <sys/sched.h>
53 #include <sys/signalvar.h>
54 #include <sys/smp.h>
55 #include <sys/syscallsubr.h>
56 #include <sys/sysctl.h>
57 #include <sys/systm.h>
58 #include <sys/uio.h>
59 #include <sys/unistd.h>
60 #include <sys/vnode.h>
61 #include <sys/syslog.h>
62 
63 #if defined(__i386__) || defined(__amd64__)
64 #include <machine/clock.h>
65 #endif
66 
67 #define curdomain PCPU_GET(domain)
68 
69 /*
70  * Sysctl tunables
71  */
72 
73 SYSCTL_DECL(_kern_hwpmc);
74 
75 /*
76  * kern.hwpmc.logbuffersize -- size of the per-cpu owner buffers.
77  */
78 
79 static int pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
80 SYSCTL_INT(_kern_hwpmc, OID_AUTO, logbuffersize, CTLFLAG_RDTUN,
81     &pmclog_buffer_size, 0, "size of log buffers in kilobytes");
82 
83 /*
84  * kern.hwpmc.nbuffers_pcpu -- number of global log buffers
85  */
86 
87 static int pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
88 SYSCTL_INT(_kern_hwpmc, OID_AUTO, nbuffers_pcpu, CTLFLAG_RDTUN,
89     &pmc_nlogbuffers_pcpu, 0, "number of log buffers per cpu");
90 
91 /*
92  * Global log buffer list and associated spin lock.
93  */
94 
95 static struct mtx pmc_kthread_mtx;	/* sleep lock */
96 
97 #define	PMCLOG_INIT_BUFFER_DESCRIPTOR(D, buf, domain) do {		\
98 	(D)->plb_fence = ((char *)(buf)) + 1024 * pmclog_buffer_size;	\
99 	(D)->plb_base = (D)->plb_ptr = ((char *)(buf));			\
100 	(D)->plb_domain = domain;					\
101 } while (0)
102 
103 #define	PMCLOG_RESET_BUFFER_DESCRIPTOR(D) do {				\
104 	(D)->plb_ptr = (D)->plb_base;					\
105 } while (0)
106 
107 /*
108  * Log file record constructors.
109  */
110 #define	_PMCLOG_TO_HEADER(T, L)						\
111 	((PMCLOG_HEADER_MAGIC << 24) | (T << 16) | ((L) & 0xFFFF))
112 
113 /* reserve LEN bytes of space and initialize the entry header */
114 #define	_PMCLOG_RESERVE_SAFE(PO, TYPE, LEN, ACTION, TSC) do {		\
115 	uint32_t *_le;							\
116 	int _len = roundup((LEN), sizeof(uint32_t));			\
117 	struct pmclog_header *ph;					\
118 									\
119 	if ((_le = pmclog_reserve((PO), _len)) == NULL) {		\
120 		ACTION;							\
121 	}								\
122 	ph = (struct pmclog_header *)_le;				\
123 	ph->pl_header =_PMCLOG_TO_HEADER(TYPE,_len);			\
124 	ph->pl_tsc = (TSC);						\
125 	_le += sizeof(*ph) / 4	/* skip over timestamp */
126 
127 /* reserve LEN bytes of space and initialize the entry header */
128 #define	_PMCLOG_RESERVE(PO, TYPE, LEN, ACTION) do {			\
129 	uint32_t *_le;							\
130 	int _len = roundup((LEN), sizeof(uint32_t));			\
131 	uint64_t tsc;							\
132 	struct pmclog_header *ph;					\
133 									\
134 	tsc = pmc_rdtsc();						\
135 	spinlock_enter();						\
136 	if ((_le = pmclog_reserve((PO), _len)) == NULL) {		\
137 		spinlock_exit();					\
138 		ACTION;							\
139 	}								\
140 	ph = (struct pmclog_header *)_le;				\
141 	ph->pl_header =_PMCLOG_TO_HEADER(TYPE,_len);			\
142 	ph->pl_tsc = tsc;						\
143 	_le += sizeof(*ph) / 4	/* skip over timestamp */
144 
145 #define	PMCLOG_RESERVE_SAFE(P, T, L, TSC)				\
146 	_PMCLOG_RESERVE_SAFE(P, T, L, return, TSC)
147 #define	PMCLOG_RESERVE(P,T,L)						\
148 	_PMCLOG_RESERVE(P, T, L, return)
149 #define	PMCLOG_RESERVE_WITH_ERROR(P, T, L)				\
150 	_PMCLOG_RESERVE(P, T, L, error = ENOMEM; goto error)
151 
152 #define	PMCLOG_EMIT32(V)	do { *_le++ = (V); } while (0)
153 #define	PMCLOG_EMIT64(V)	do { 					\
154 	*_le++ = (uint32_t) ((V) & 0xFFFFFFFF);				\
155 	*_le++ = (uint32_t) (((V) >> 32) & 0xFFFFFFFF);			\
156 } while (0)
157 
158 
159 /* Emit a string.  Caution: does NOT update _le, so needs to be last */
160 #define	PMCLOG_EMITSTRING(S,L)	do {					\
161 	bcopy((S), _le, (L));						\
162 } while (0)
163 #define	PMCLOG_EMITNULLSTRING(L) do {					\
164 	bzero(_le, (L));						\
165 } while (0)
166 
167 #define	PMCLOG_DESPATCH_SAFE(PO)					\
168 	pmclog_release((PO));						\
169 } while (0)
170 
171 #define	PMCLOG_DESPATCH_SCHED_LOCK(PO)					\
172 	pmclog_release_flags((PO), 0);					\
173 } while (0)
174 
175 #define	PMCLOG_DESPATCH(PO)						\
176 	pmclog_release((PO));						\
177 	spinlock_exit();						\
178 } while (0)
179 
180 #define	PMCLOG_DESPATCH_SYNC(PO)					\
181 	pmclog_schedule_io((PO), 1);					\
182 	spinlock_exit();						\
183 } while (0)
184 
185 #define TSDELTA 4
186 /*
187  * Assertions about the log file format.
188  */
189 CTASSERT(sizeof(struct pmclog_callchain) == 7*4 + TSDELTA +
190     PMC_CALLCHAIN_DEPTH_MAX*sizeof(uintfptr_t));
191 CTASSERT(sizeof(struct pmclog_closelog) == 3*4 + TSDELTA);
192 CTASSERT(sizeof(struct pmclog_dropnotify) == 3*4 + TSDELTA);
193 CTASSERT(sizeof(struct pmclog_map_in) == PATH_MAX + TSDELTA +
194     5*4 + sizeof(uintfptr_t));
195 CTASSERT(offsetof(struct pmclog_map_in,pl_pathname) ==
196     5*4 + TSDELTA + sizeof(uintfptr_t));
197 CTASSERT(sizeof(struct pmclog_map_out) == 5*4 + 2*sizeof(uintfptr_t) + TSDELTA);
198 CTASSERT(sizeof(struct pmclog_pmcallocate) == 9*4 + TSDELTA);
199 CTASSERT(sizeof(struct pmclog_pmcattach) == 5*4 + PATH_MAX + TSDELTA);
200 CTASSERT(offsetof(struct pmclog_pmcattach,pl_pathname) == 5*4 + TSDELTA);
201 CTASSERT(sizeof(struct pmclog_pmcdetach) == 5*4 + TSDELTA);
202 CTASSERT(sizeof(struct pmclog_proccsw) == 7*4 + 8 + TSDELTA);
203 CTASSERT(sizeof(struct pmclog_procexec) == 5*4 + PATH_MAX +
204     2*sizeof(uintptr_t) + TSDELTA);
205 CTASSERT(offsetof(struct pmclog_procexec,pl_pathname) == 5*4 + TSDELTA +
206     2*sizeof(uintptr_t));
207 CTASSERT(sizeof(struct pmclog_procexit) == 5*4 + 8 + TSDELTA);
208 CTASSERT(sizeof(struct pmclog_procfork) == 5*4 + TSDELTA);
209 CTASSERT(sizeof(struct pmclog_sysexit) == 6*4);
210 CTASSERT(sizeof(struct pmclog_userdata) == 6*4);
211 
212 /*
213  * Log buffer structure
214  */
215 
216 struct pmclog_buffer {
217 	TAILQ_ENTRY(pmclog_buffer) plb_next;
218 	char 		*plb_base;
219 	char		*plb_ptr;
220 	char 		*plb_fence;
221 	uint16_t	 plb_domain;
222 } __aligned(CACHE_LINE_SIZE);
223 
224 /*
225  * Prototypes
226  */
227 
228 static int pmclog_get_buffer(struct pmc_owner *po);
229 static void pmclog_loop(void *arg);
230 static void pmclog_release(struct pmc_owner *po);
231 static uint32_t *pmclog_reserve(struct pmc_owner *po, int length);
232 static void pmclog_schedule_io(struct pmc_owner *po, int wakeup);
233 static void pmclog_schedule_all(struct pmc_owner *po);
234 static void pmclog_stop_kthread(struct pmc_owner *po);
235 
236 /*
237  * Helper functions
238  */
239 
240 static inline void
pmc_plb_rele_unlocked(struct pmclog_buffer * plb)241 pmc_plb_rele_unlocked(struct pmclog_buffer *plb)
242 {
243 	TAILQ_INSERT_HEAD(&pmc_dom_hdrs[plb->plb_domain]->pdbh_head, plb, plb_next);
244 }
245 
246 static inline void
pmc_plb_rele(struct pmclog_buffer * plb)247 pmc_plb_rele(struct pmclog_buffer *plb)
248 {
249 	mtx_lock_spin(&pmc_dom_hdrs[plb->plb_domain]->pdbh_mtx);
250 	pmc_plb_rele_unlocked(plb);
251 	mtx_unlock_spin(&pmc_dom_hdrs[plb->plb_domain]->pdbh_mtx);
252 }
253 
254 /*
255  * Get a log buffer
256  */
257 static int
pmclog_get_buffer(struct pmc_owner * po)258 pmclog_get_buffer(struct pmc_owner *po)
259 {
260 	struct pmclog_buffer *plb;
261 	int domain;
262 
263 	KASSERT(po->po_curbuf[curcpu] == NULL,
264 	    ("[pmclog,%d] po=%p current buffer still valid", __LINE__, po));
265 
266 	domain = curdomain;
267 	MPASS(pmc_dom_hdrs[domain]);
268 	mtx_lock_spin(&pmc_dom_hdrs[domain]->pdbh_mtx);
269 	if ((plb = TAILQ_FIRST(&pmc_dom_hdrs[domain]->pdbh_head)) != NULL)
270 		TAILQ_REMOVE(&pmc_dom_hdrs[domain]->pdbh_head, plb, plb_next);
271 	mtx_unlock_spin(&pmc_dom_hdrs[domain]->pdbh_mtx);
272 
273 	PMCDBG2(LOG,GTB,1, "po=%p plb=%p", po, plb);
274 
275 #ifdef	HWPMC_DEBUG
276 	if (plb)
277 		KASSERT(plb->plb_ptr == plb->plb_base &&
278 		    plb->plb_base < plb->plb_fence,
279 		    ("[pmclog,%d] po=%p buffer invariants: ptr=%p "
280 		    "base=%p fence=%p", __LINE__, po, plb->plb_ptr,
281 		    plb->plb_base, plb->plb_fence));
282 #endif
283 
284 	po->po_curbuf[curcpu] = plb;
285 
286 	/* update stats */
287 	counter_u64_add(pmc_stats.pm_buffer_requests, 1);
288 	if (plb == NULL)
289 		counter_u64_add(pmc_stats.pm_buffer_requests_failed, 1);
290 
291 	return (plb ? 0 : ENOMEM);
292 }
293 
294 struct pmclog_proc_init_args {
295 	struct proc *kthr;
296 	struct pmc_owner *po;
297 	bool exit;
298 	bool acted;
299 };
300 
301 int
pmclog_proc_create(struct thread * td,void ** handlep)302 pmclog_proc_create(struct thread *td, void **handlep)
303 {
304 	struct pmclog_proc_init_args *ia;
305 	int error;
306 
307 	ia = malloc(sizeof(*ia), M_TEMP, M_WAITOK | M_ZERO);
308 	error = kproc_create(pmclog_loop, ia, &ia->kthr,
309 	    RFHIGHPID, 0, "hwpmc: proc(%d)", td->td_proc->p_pid);
310 	if (error == 0)
311 		*handlep = ia;
312 	return (error);
313 }
314 
315 void
pmclog_proc_ignite(void * handle,struct pmc_owner * po)316 pmclog_proc_ignite(void *handle, struct pmc_owner *po)
317 {
318 	struct pmclog_proc_init_args *ia;
319 
320 	ia = handle;
321 	mtx_lock(&pmc_kthread_mtx);
322 	MPASS(!ia->acted);
323 	MPASS(ia->po == NULL);
324 	MPASS(!ia->exit);
325 	MPASS(ia->kthr != NULL);
326 	if (po == NULL) {
327 		ia->exit = true;
328 	} else {
329 		ia->po = po;
330 		KASSERT(po->po_kthread == NULL,
331 		    ("[pmclog,%d] po=%p kthread (%p) already present",
332 		    __LINE__, po, po->po_kthread));
333 		po->po_kthread = ia->kthr;
334 	}
335 	wakeup(ia);
336 	while (!ia->acted)
337 		msleep(ia, &pmc_kthread_mtx, PWAIT, "pmclogw", 0);
338 	mtx_unlock(&pmc_kthread_mtx);
339 	free(ia, M_TEMP);
340 }
341 
342 /*
343  * Log handler loop.
344  *
345  * This function is executed by each pmc owner's helper thread.
346  */
347 static void
pmclog_loop(void * arg)348 pmclog_loop(void *arg)
349 {
350 	struct pmclog_proc_init_args *ia;
351 	struct pmc_owner *po;
352 	struct pmclog_buffer *lb;
353 	struct proc *p;
354 	struct ucred *ownercred;
355 	struct ucred *mycred;
356 	struct thread *td;
357 	sigset_t unb;
358 	struct uio auio;
359 	struct iovec aiov;
360 	size_t nbytes;
361 	int error;
362 
363 	td = curthread;
364 
365 	SIGEMPTYSET(unb);
366 	SIGADDSET(unb, SIGHUP);
367 	(void)kern_sigprocmask(td, SIG_UNBLOCK, &unb, NULL, 0);
368 
369 	ia = arg;
370 	MPASS(ia->kthr == curproc);
371 	MPASS(!ia->acted);
372 	mtx_lock(&pmc_kthread_mtx);
373 	while (ia->po == NULL && !ia->exit)
374 		msleep(ia, &pmc_kthread_mtx, PWAIT, "pmclogi", 0);
375 	if (ia->exit) {
376 		ia->acted = true;
377 		wakeup(ia);
378 		mtx_unlock(&pmc_kthread_mtx);
379 		kproc_exit(0);
380 	}
381 	MPASS(ia->po != NULL);
382 	po = ia->po;
383 	ia->acted = true;
384 	wakeup(ia);
385 	mtx_unlock(&pmc_kthread_mtx);
386 	ia = NULL;
387 
388 	p = po->po_owner;
389 	mycred = td->td_ucred;
390 
391 	PROC_LOCK(p);
392 	ownercred = crhold(p->p_ucred);
393 	PROC_UNLOCK(p);
394 
395 	PMCDBG2(LOG,INI,1, "po=%p kt=%p", po, po->po_kthread);
396 	KASSERT(po->po_kthread == curthread->td_proc,
397 	    ("[pmclog,%d] proc mismatch po=%p po/kt=%p curproc=%p", __LINE__,
398 		po, po->po_kthread, curthread->td_proc));
399 
400 	lb = NULL;
401 
402 
403 	/*
404 	 * Loop waiting for I/O requests to be added to the owner
405 	 * struct's queue.  The loop is exited when the log file
406 	 * is deconfigured.
407 	 */
408 
409 	mtx_lock(&pmc_kthread_mtx);
410 
411 	for (;;) {
412 
413 		/* check if we've been asked to exit */
414 		if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
415 			break;
416 
417 		if (lb == NULL) { /* look for a fresh buffer to write */
418 			mtx_lock_spin(&po->po_mtx);
419 			if ((lb = TAILQ_FIRST(&po->po_logbuffers)) == NULL) {
420 				mtx_unlock_spin(&po->po_mtx);
421 
422 				/* No more buffers and shutdown required. */
423 				if (po->po_flags & PMC_PO_SHUTDOWN)
424 					break;
425 
426 				(void) msleep(po, &pmc_kthread_mtx, PWAIT,
427 				    "pmcloop", 250);
428 				continue;
429 			}
430 
431 			TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
432 			mtx_unlock_spin(&po->po_mtx);
433 		}
434 
435 		mtx_unlock(&pmc_kthread_mtx);
436 
437 		/* process the request */
438 		PMCDBG3(LOG,WRI,2, "po=%p base=%p ptr=%p", po,
439 		    lb->plb_base, lb->plb_ptr);
440 		/* change our thread's credentials before issuing the I/O */
441 
442 		aiov.iov_base = lb->plb_base;
443 		aiov.iov_len  = nbytes = lb->plb_ptr - lb->plb_base;
444 
445 		auio.uio_iov    = &aiov;
446 		auio.uio_iovcnt = 1;
447 		auio.uio_offset = -1;
448 		auio.uio_resid  = nbytes;
449 		auio.uio_rw     = UIO_WRITE;
450 		auio.uio_segflg = UIO_SYSSPACE;
451 		auio.uio_td     = td;
452 
453 		/* switch thread credentials -- see kern_ktrace.c */
454 		td->td_ucred = ownercred;
455 		error = fo_write(po->po_file, &auio, ownercred, 0, td);
456 		td->td_ucred = mycred;
457 
458 		if (error) {
459 			/* XXX some errors are recoverable */
460 			/* send a SIGIO to the owner and exit */
461 			PROC_LOCK(p);
462 			kern_psignal(p, SIGIO);
463 			PROC_UNLOCK(p);
464 
465 			mtx_lock(&pmc_kthread_mtx);
466 
467 			po->po_error = error; /* save for flush log */
468 
469 			PMCDBG2(LOG,WRI,2, "po=%p error=%d", po, error);
470 
471 			break;
472 		}
473 
474 		mtx_lock(&pmc_kthread_mtx);
475 
476 		/* put the used buffer back into the global pool */
477 		PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
478 
479 		pmc_plb_rele(lb);
480 		lb = NULL;
481 	}
482 
483 	wakeup_one(po->po_kthread);
484 	po->po_kthread = NULL;
485 
486 	mtx_unlock(&pmc_kthread_mtx);
487 
488 	/* return the current I/O buffer to the global pool */
489 	if (lb) {
490 		PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
491 
492 		pmc_plb_rele(lb);
493 	}
494 
495 	/*
496 	 * Exit this thread, signalling the waiter
497 	 */
498 
499 	crfree(ownercred);
500 
501 	kproc_exit(0);
502 }
503 
504 /*
505  * Release and log entry and schedule an I/O if needed.
506  */
507 
508 static void
pmclog_release_flags(struct pmc_owner * po,int wakeup)509 pmclog_release_flags(struct pmc_owner *po, int wakeup)
510 {
511 	struct pmclog_buffer *plb;
512 
513 	plb = po->po_curbuf[curcpu];
514 	KASSERT(plb->plb_ptr >= plb->plb_base,
515 	    ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
516 		po, plb->plb_ptr, plb->plb_base));
517 	KASSERT(plb->plb_ptr <= plb->plb_fence,
518 	    ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
519 		po, plb->plb_ptr, plb->plb_fence));
520 
521 	/* schedule an I/O if we've filled a buffer */
522 	if (plb->plb_ptr >= plb->plb_fence)
523 		pmclog_schedule_io(po, wakeup);
524 
525 	PMCDBG1(LOG,REL,1, "po=%p", po);
526 }
527 
528 static void
pmclog_release(struct pmc_owner * po)529 pmclog_release(struct pmc_owner *po)
530 {
531 
532 	pmclog_release_flags(po, 1);
533 }
534 
535 
536 /*
537  * Attempt to reserve 'length' bytes of space in an owner's log
538  * buffer.  The function returns a pointer to 'length' bytes of space
539  * if there was enough space or returns NULL if no space was
540  * available.  Non-null returns do so with the po mutex locked.  The
541  * caller must invoke pmclog_release() on the pmc owner structure
542  * when done.
543  */
544 
545 static uint32_t *
pmclog_reserve(struct pmc_owner * po,int length)546 pmclog_reserve(struct pmc_owner *po, int length)
547 {
548 	uintptr_t newptr, oldptr __diagused;
549 	struct pmclog_buffer *plb, **pplb;
550 
551 	PMCDBG2(LOG,ALL,1, "po=%p len=%d", po, length);
552 
553 	KASSERT(length % sizeof(uint32_t) == 0,
554 	    ("[pmclog,%d] length not a multiple of word size", __LINE__));
555 
556 	/* No more data when shutdown in progress. */
557 	if (po->po_flags & PMC_PO_SHUTDOWN)
558 		return (NULL);
559 
560 	pplb = &po->po_curbuf[curcpu];
561 	if (*pplb == NULL && pmclog_get_buffer(po) != 0)
562 		goto fail;
563 
564 	KASSERT(*pplb != NULL,
565 	    ("[pmclog,%d] po=%p no current buffer", __LINE__, po));
566 
567 	plb = *pplb;
568 	KASSERT(plb->plb_ptr >= plb->plb_base &&
569 	    plb->plb_ptr <= plb->plb_fence,
570 	    ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
571 		__LINE__, po, plb->plb_ptr, plb->plb_base,
572 		plb->plb_fence));
573 
574 	oldptr = (uintptr_t) plb->plb_ptr;
575 	newptr = oldptr + length;
576 
577 	KASSERT(oldptr != (uintptr_t) NULL,
578 	    ("[pmclog,%d] po=%p Null log buffer pointer", __LINE__, po));
579 
580 	/*
581 	 * If we have space in the current buffer, return a pointer to
582 	 * available space with the PO structure locked.
583 	 */
584 	if (newptr <= (uintptr_t) plb->plb_fence) {
585 		plb->plb_ptr = (char *) newptr;
586 		goto done;
587 	}
588 
589 	/*
590 	 * Otherwise, schedule the current buffer for output and get a
591 	 * fresh buffer.
592 	 */
593 	pmclog_schedule_io(po, 0);
594 
595 	if (pmclog_get_buffer(po) != 0)
596 		goto fail;
597 
598 	plb = *pplb;
599 	KASSERT(plb != NULL,
600 	    ("[pmclog,%d] po=%p no current buffer", __LINE__, po));
601 
602 	KASSERT(plb->plb_ptr != NULL,
603 	    ("[pmclog,%d] null return from pmc_get_log_buffer", __LINE__));
604 
605 	KASSERT(plb->plb_ptr == plb->plb_base &&
606 	    plb->plb_ptr <= plb->plb_fence,
607 	    ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
608 		__LINE__, po, plb->plb_ptr, plb->plb_base,
609 		plb->plb_fence));
610 
611 	oldptr = (uintptr_t) plb->plb_ptr;
612 
613  done:
614 	return ((uint32_t *) oldptr);
615  fail:
616 	return (NULL);
617 }
618 
619 /*
620  * Schedule an I/O.
621  *
622  * Transfer the current buffer to the helper kthread.
623  */
624 
625 static void
pmclog_schedule_io(struct pmc_owner * po,int wakeup)626 pmclog_schedule_io(struct pmc_owner *po, int wakeup)
627 {
628 	struct pmclog_buffer *plb;
629 
630 	plb = po->po_curbuf[curcpu];
631 	po->po_curbuf[curcpu] = NULL;
632 	KASSERT(plb != NULL,
633 	    ("[pmclog,%d] schedule_io with null buffer po=%p", __LINE__, po));
634 	KASSERT(plb->plb_ptr >= plb->plb_base,
635 	    ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
636 		po, plb->plb_ptr, plb->plb_base));
637 	KASSERT(plb->plb_ptr <= plb->plb_fence,
638 	    ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
639 		po, plb->plb_ptr, plb->plb_fence));
640 
641 	PMCDBG1(LOG,SIO, 1, "po=%p", po);
642 
643 	/*
644 	 * Add the current buffer to the tail of the buffer list and
645 	 * wakeup the helper.
646 	 */
647 	mtx_lock_spin(&po->po_mtx);
648 	TAILQ_INSERT_TAIL(&po->po_logbuffers, plb, plb_next);
649 	mtx_unlock_spin(&po->po_mtx);
650 	if (wakeup)
651 		wakeup_one(po);
652 }
653 
654 /*
655  * Stop the helper kthread.
656  */
657 
658 static void
pmclog_stop_kthread(struct pmc_owner * po)659 pmclog_stop_kthread(struct pmc_owner *po)
660 {
661 
662 	mtx_lock(&pmc_kthread_mtx);
663 	po->po_flags &= ~PMC_PO_OWNS_LOGFILE;
664 	if (po->po_kthread != NULL) {
665 		PROC_LOCK(po->po_kthread);
666 		kern_psignal(po->po_kthread, SIGHUP);
667 		PROC_UNLOCK(po->po_kthread);
668 	}
669 	wakeup_one(po);
670 	while (po->po_kthread)
671 		msleep(po->po_kthread, &pmc_kthread_mtx, PPAUSE, "pmckstp", 0);
672 	mtx_unlock(&pmc_kthread_mtx);
673 }
674 
675 /*
676  * Public functions
677  */
678 
679 /*
680  * Configure a log file for pmc owner 'po'.
681  *
682  * Parameter 'logfd' is a file handle referencing an open file in the
683  * owner process.  This file needs to have been opened for writing.
684  */
685 
686 int
pmclog_configure_log(struct pmc_mdep * md,struct pmc_owner * po,int logfd)687 pmclog_configure_log(struct pmc_mdep *md, struct pmc_owner *po, int logfd)
688 {
689 	struct proc *p;
690 	struct timespec ts;
691 	int error;
692 
693 	sx_assert(&pmc_sx, SA_XLOCKED);
694 	PMCDBG2(LOG,CFG,1, "config po=%p logfd=%d", po, logfd);
695 
696 	p = po->po_owner;
697 
698 	/* return EBUSY if a log file was already present */
699 	if (po->po_flags & PMC_PO_OWNS_LOGFILE)
700 		return (EBUSY);
701 
702 	KASSERT(po->po_file == NULL,
703 	    ("[pmclog,%d] po=%p file (%p) already present", __LINE__, po,
704 		po->po_file));
705 
706 	/* get a reference to the file state */
707 	error = fget_write(curthread, logfd, &cap_write_rights, &po->po_file);
708 	if (error)
709 		goto error;
710 
711 	/* mark process as owning a log file */
712 	po->po_flags |= PMC_PO_OWNS_LOGFILE;
713 
714 	/* mark process as using HWPMCs */
715 	PROC_LOCK(p);
716 	p->p_flag |= P_HWPMC;
717 	PROC_UNLOCK(p);
718 	nanotime(&ts);
719 	/* create a log initialization entry */
720 	PMCLOG_RESERVE_WITH_ERROR(po, PMCLOG_TYPE_INITIALIZE,
721 	    sizeof(struct pmclog_initialize));
722 	PMCLOG_EMIT32(PMC_VERSION);
723 	PMCLOG_EMIT32(md->pmd_cputype);
724 #if defined(__i386__) || defined(__amd64__)
725 	PMCLOG_EMIT64(tsc_freq);
726 #else
727 	/* other architectures will need to fill this in */
728 	PMCLOG_EMIT32(0);
729 	PMCLOG_EMIT32(0);
730 #endif
731 	memcpy(_le, &ts, sizeof(ts));
732 	_le += sizeof(ts)/4;
733 	PMCLOG_EMITSTRING(pmc_cpuid, PMC_CPUID_LEN);
734 	PMCLOG_DESPATCH_SYNC(po);
735 
736 	return (0);
737 
738  error:
739 	KASSERT(po->po_kthread == NULL, ("[pmclog,%d] po=%p kthread not "
740 	    "stopped", __LINE__, po));
741 
742 	if (po->po_file)
743 		(void) fdrop(po->po_file, curthread);
744 	po->po_file  = NULL;	/* clear file and error state */
745 	po->po_error = 0;
746 	po->po_flags &= ~PMC_PO_OWNS_LOGFILE;
747 
748 	return (error);
749 }
750 
751 
752 /*
753  * De-configure a log file.  This will throw away any buffers queued
754  * for this owner process.
755  */
756 
757 int
pmclog_deconfigure_log(struct pmc_owner * po)758 pmclog_deconfigure_log(struct pmc_owner *po)
759 {
760 	int error;
761 	struct pmclog_buffer *lb;
762 	struct pmc_binding pb;
763 
764 	PMCDBG1(LOG,CFG,1, "de-config po=%p", po);
765 
766 	if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
767 		return (EINVAL);
768 
769 	KASSERT(po->po_sscount == 0,
770 	    ("[pmclog,%d] po=%p still owning SS PMCs", __LINE__, po));
771 	KASSERT(po->po_file != NULL,
772 	    ("[pmclog,%d] po=%p no log file", __LINE__, po));
773 
774 	/* stop the kthread, this will reset the 'OWNS_LOGFILE' flag */
775 	pmclog_stop_kthread(po);
776 
777 	KASSERT(po->po_kthread == NULL,
778 	    ("[pmclog,%d] po=%p kthread not stopped", __LINE__, po));
779 
780 	/* return all queued log buffers to the global pool */
781 	while ((lb = TAILQ_FIRST(&po->po_logbuffers)) != NULL) {
782 		TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
783 		PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
784 		pmc_plb_rele(lb);
785 	}
786 	pmc_save_cpu_binding(&pb);
787 	for (int i = 0; i < mp_ncpus; i++) {
788 		pmc_select_cpu(i);
789 		/* return the 'current' buffer to the global pool */
790 		if ((lb = po->po_curbuf[curcpu]) != NULL) {
791 			PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
792 			pmc_plb_rele(lb);
793 		}
794 	}
795 	pmc_restore_cpu_binding(&pb);
796 
797 	/* drop a reference to the fd */
798 	if (po->po_file != NULL) {
799 		error = fdrop(po->po_file, curthread);
800 		po->po_file = NULL;
801 	} else
802 		error = 0;
803 	po->po_error = 0;
804 
805 	return (error);
806 }
807 
808 /*
809  * Flush a process' log buffer.
810  */
811 
812 int
pmclog_flush(struct pmc_owner * po,int force)813 pmclog_flush(struct pmc_owner *po, int force)
814 {
815 	int error;
816 
817 	PMCDBG1(LOG,FLS,1, "po=%p", po);
818 
819 	/*
820 	 * If there is a pending error recorded by the logger thread,
821 	 * return that.
822 	 */
823 	if (po->po_error)
824 		return (po->po_error);
825 
826 	error = 0;
827 
828 	/*
829 	 * Check that we do have an active log file.
830 	 */
831 	mtx_lock(&pmc_kthread_mtx);
832 	if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) {
833 		error = EINVAL;
834 		goto error;
835 	}
836 
837 	pmclog_schedule_all(po);
838  error:
839 	mtx_unlock(&pmc_kthread_mtx);
840 
841 	return (error);
842 }
843 
844 static void
pmclog_schedule_one_cond(struct pmc_owner * po)845 pmclog_schedule_one_cond(struct pmc_owner *po)
846 {
847 	struct pmclog_buffer *plb;
848 	int cpu;
849 
850 	spinlock_enter();
851 	cpu = curcpu;
852 	/* tell hardclock not to run again */
853 	if (PMC_CPU_HAS_SAMPLES(cpu))
854 		PMC_CALL_HOOK_UNLOCKED(curthread, PMC_FN_DO_SAMPLES, NULL);
855 
856 	plb = po->po_curbuf[cpu];
857 	if (plb && plb->plb_ptr != plb->plb_base)
858 		pmclog_schedule_io(po, 1);
859 	spinlock_exit();
860 }
861 
862 static void
pmclog_schedule_all(struct pmc_owner * po)863 pmclog_schedule_all(struct pmc_owner *po)
864 {
865 	struct pmc_binding pb;
866 
867 	/*
868 	 * Schedule the current buffer if any and not empty.
869 	 */
870 	pmc_save_cpu_binding(&pb);
871 	for (int i = 0; i < mp_ncpus; i++) {
872 		pmc_select_cpu(i);
873 		pmclog_schedule_one_cond(po);
874 	}
875 	pmc_restore_cpu_binding(&pb);
876 }
877 
878 int
pmclog_close(struct pmc_owner * po)879 pmclog_close(struct pmc_owner *po)
880 {
881 
882 	PMCDBG1(LOG,CLO,1, "po=%p", po);
883 
884 	pmclog_process_closelog(po);
885 
886 	mtx_lock(&pmc_kthread_mtx);
887 	/*
888 	 * Initiate shutdown: no new data queued,
889 	 * thread will close file on last block.
890 	 */
891 	po->po_flags |= PMC_PO_SHUTDOWN;
892 	/* give time for all to see */
893 	DELAY(50);
894 
895 	/*
896 	 * Schedule the current buffer.
897 	 */
898 	pmclog_schedule_all(po);
899 	wakeup_one(po);
900 
901 	mtx_unlock(&pmc_kthread_mtx);
902 
903 	return (0);
904 }
905 
906 void
pmclog_process_callchain(struct pmc * pm,struct pmc_sample * ps)907 pmclog_process_callchain(struct pmc *pm, struct pmc_sample *ps)
908 {
909 	int n, recordlen;
910 	uint32_t flags;
911 	struct pmc_owner *po;
912 
913 	PMCDBG3(LOG,SAM,1,"pm=%p pid=%d n=%d", pm, ps->ps_pid,
914 	    ps->ps_nsamples);
915 
916 	recordlen = offsetof(struct pmclog_callchain, pl_pc) +
917 	    ps->ps_nsamples * sizeof(uintfptr_t);
918 	po = pm->pm_owner;
919 	flags = PMC_CALLCHAIN_TO_CPUFLAGS(ps->ps_cpu,ps->ps_flags);
920 	PMCLOG_RESERVE_SAFE(po, PMCLOG_TYPE_CALLCHAIN, recordlen, ps->ps_tsc);
921 	PMCLOG_EMIT32(ps->ps_pid);
922 	PMCLOG_EMIT32(ps->ps_tid);
923 	PMCLOG_EMIT32(pm->pm_id);
924 	PMCLOG_EMIT32(flags);
925 	for (n = 0; n < ps->ps_nsamples; n++)
926 		PMCLOG_EMITADDR(ps->ps_pc[n]);
927 	PMCLOG_DESPATCH_SAFE(po);
928 }
929 
930 void
pmclog_process_closelog(struct pmc_owner * po)931 pmclog_process_closelog(struct pmc_owner *po)
932 {
933 	PMCLOG_RESERVE(po, PMCLOG_TYPE_CLOSELOG,
934 	    sizeof(struct pmclog_closelog));
935 	PMCLOG_DESPATCH_SYNC(po);
936 }
937 
938 void
pmclog_process_dropnotify(struct pmc_owner * po)939 pmclog_process_dropnotify(struct pmc_owner *po)
940 {
941 	PMCLOG_RESERVE(po, PMCLOG_TYPE_DROPNOTIFY,
942 	    sizeof(struct pmclog_dropnotify));
943 	PMCLOG_DESPATCH(po);
944 }
945 
946 void
pmclog_process_map_in(struct pmc_owner * po,pid_t pid,uintfptr_t start,const char * path)947 pmclog_process_map_in(struct pmc_owner *po, pid_t pid, uintfptr_t start,
948     const char *path)
949 {
950 	struct pmclog_map_in *mi;
951 	int pathlen, recordlen;
952 
953 	KASSERT(path != NULL, ("[pmclog,%d] map-in, null path", __LINE__));
954 
955 	pathlen = strlen(path) + 1;	/* #bytes for path name */
956 	recordlen = offsetof(struct pmclog_map_in, pl_pathname) +
957 	    pathlen;
958 
959 	PMCLOG_RESERVE(po, PMCLOG_TYPE_MAP_IN, recordlen);
960 	mi = (struct pmclog_map_in *)ph;
961 	PMCLOG_EMIT32(pid);
962 	mi->pl_u = 0;
963 	mi->pl_pageshift = PAGE_SHIFT;
964 	PMCLOG_EMIT32(mi->pl_u);
965 	PMCLOG_EMITADDR(start);
966 	PMCLOG_EMITSTRING(path,pathlen);
967 	PMCLOG_DESPATCH_SYNC(po);
968 }
969 
970 void
pmclog_process_map_out(struct pmc_owner * po,pid_t pid,uintfptr_t start,uintfptr_t end)971 pmclog_process_map_out(struct pmc_owner *po, pid_t pid, uintfptr_t start,
972     uintfptr_t end)
973 {
974 	KASSERT(start <= end, ("[pmclog,%d] start > end", __LINE__));
975 
976 	PMCLOG_RESERVE(po, PMCLOG_TYPE_MAP_OUT, sizeof(struct pmclog_map_out));
977 	PMCLOG_EMIT32(pid);
978 	PMCLOG_EMIT32(0);
979 	PMCLOG_EMITADDR(start);
980 	PMCLOG_EMITADDR(end);
981 	PMCLOG_DESPATCH(po);
982 }
983 
984 void
pmclog_process_pmcallocate(struct pmc * pm)985 pmclog_process_pmcallocate(struct pmc *pm)
986 {
987 	struct pmc_owner *po;
988 	struct pmc_soft *ps;
989 
990 	po = pm->pm_owner;
991 
992 	PMCDBG1(LOG,ALL,1, "pm=%p", pm);
993 
994 	if (PMC_TO_CLASS(pm) == PMC_CLASS_SOFT) {
995 		PMCLOG_RESERVE(po, PMCLOG_TYPE_PMCALLOCATEDYN,
996 		    sizeof(struct pmclog_pmcallocatedyn));
997 		PMCLOG_EMIT32(pm->pm_id);
998 		PMCLOG_EMIT32(pm->pm_event);
999 		PMCLOG_EMIT32(pm->pm_flags);
1000 		PMCLOG_EMIT32(0);
1001 		PMCLOG_EMIT64(pm->pm_sc.pm_reloadcount);
1002 		ps = pmc_soft_ev_acquire(pm->pm_event);
1003 		if (ps != NULL)
1004 			PMCLOG_EMITSTRING(ps->ps_ev.pm_ev_name,PMC_NAME_MAX);
1005 		else
1006 			PMCLOG_EMITNULLSTRING(PMC_NAME_MAX);
1007 		pmc_soft_ev_release(ps);
1008 		PMCLOG_DESPATCH_SYNC(po);
1009 	} else {
1010 		PMCLOG_RESERVE(po, PMCLOG_TYPE_PMCALLOCATE,
1011 		    sizeof(struct pmclog_pmcallocate));
1012 		PMCLOG_EMIT32(pm->pm_id);
1013 		PMCLOG_EMIT32(pm->pm_event);
1014 		PMCLOG_EMIT32(pm->pm_flags);
1015 		PMCLOG_EMIT32(0);
1016 		PMCLOG_EMIT64(pm->pm_sc.pm_reloadcount);
1017 		PMCLOG_DESPATCH_SYNC(po);
1018 	}
1019 }
1020 
1021 void
pmclog_process_pmcattach(struct pmc * pm,pid_t pid,char * path)1022 pmclog_process_pmcattach(struct pmc *pm, pid_t pid, char *path)
1023 {
1024 	int pathlen, recordlen;
1025 	struct pmc_owner *po;
1026 
1027 	PMCDBG2(LOG,ATT,1,"pm=%p pid=%d", pm, pid);
1028 
1029 	po = pm->pm_owner;
1030 
1031 	pathlen = strlen(path) + 1;	/* #bytes for the string */
1032 	recordlen = offsetof(struct pmclog_pmcattach, pl_pathname) + pathlen;
1033 
1034 	PMCLOG_RESERVE(po, PMCLOG_TYPE_PMCATTACH, recordlen);
1035 	PMCLOG_EMIT32(pm->pm_id);
1036 	PMCLOG_EMIT32(pid);
1037 	PMCLOG_EMITSTRING(path, pathlen);
1038 	PMCLOG_DESPATCH_SYNC(po);
1039 }
1040 
1041 void
pmclog_process_pmcdetach(struct pmc * pm,pid_t pid)1042 pmclog_process_pmcdetach(struct pmc *pm, pid_t pid)
1043 {
1044 	struct pmc_owner *po;
1045 
1046 	PMCDBG2(LOG,ATT,1,"!pm=%p pid=%d", pm, pid);
1047 
1048 	po = pm->pm_owner;
1049 
1050 	PMCLOG_RESERVE(po, PMCLOG_TYPE_PMCDETACH,
1051 	    sizeof(struct pmclog_pmcdetach));
1052 	PMCLOG_EMIT32(pm->pm_id);
1053 	PMCLOG_EMIT32(pid);
1054 	PMCLOG_DESPATCH_SYNC(po);
1055 }
1056 
1057 void
pmclog_process_proccreate(struct pmc_owner * po,struct proc * p,int sync)1058 pmclog_process_proccreate(struct pmc_owner *po, struct proc *p, int sync)
1059 {
1060 	if (sync) {
1061 		PMCLOG_RESERVE(po, PMCLOG_TYPE_PROC_CREATE,
1062 		    sizeof(struct pmclog_proccreate));
1063 		PMCLOG_EMIT32(p->p_pid);
1064 		PMCLOG_EMIT32(p->p_flag);
1065 		PMCLOG_EMITSTRING(p->p_comm, MAXCOMLEN+1);
1066 		PMCLOG_DESPATCH_SYNC(po);
1067 	} else {
1068 		PMCLOG_RESERVE(po, PMCLOG_TYPE_PROC_CREATE,
1069 		    sizeof(struct pmclog_proccreate));
1070 		PMCLOG_EMIT32(p->p_pid);
1071 		PMCLOG_EMIT32(p->p_flag);
1072 		PMCLOG_EMITSTRING(p->p_comm, MAXCOMLEN+1);
1073 		PMCLOG_DESPATCH(po);
1074 	}
1075 }
1076 
1077 /*
1078  * Log a context switch event to the log file.
1079  */
1080 
1081 void
pmclog_process_proccsw(struct pmc * pm,struct pmc_process * pp,pmc_value_t v,struct thread * td)1082 pmclog_process_proccsw(struct pmc *pm, struct pmc_process *pp, pmc_value_t v, struct thread *td)
1083 {
1084 	struct pmc_owner *po;
1085 
1086 	KASSERT(pm->pm_flags & PMC_F_LOG_PROCCSW,
1087 	    ("[pmclog,%d] log-process-csw called gratuitously", __LINE__));
1088 
1089 	PMCDBG3(LOG,SWO,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
1090 	    v);
1091 
1092 	po = pm->pm_owner;
1093 
1094 	PMCLOG_RESERVE_SAFE(po, PMCLOG_TYPE_PROCCSW,
1095 	    sizeof(struct pmclog_proccsw), pmc_rdtsc());
1096 	PMCLOG_EMIT64(v);
1097 	PMCLOG_EMIT32(pm->pm_id);
1098 	PMCLOG_EMIT32(pp->pp_proc->p_pid);
1099 	PMCLOG_EMIT32(td->td_tid);
1100 	PMCLOG_EMIT32(0);
1101 	PMCLOG_DESPATCH_SCHED_LOCK(po);
1102 }
1103 
1104 void
pmclog_process_procexec(struct pmc_owner * po,pmc_id_t pmid,pid_t pid,uintptr_t baseaddr,uintptr_t dynaddr,char * path)1105 pmclog_process_procexec(struct pmc_owner *po, pmc_id_t pmid, pid_t pid,
1106     uintptr_t baseaddr, uintptr_t dynaddr, char *path)
1107 {
1108 	int pathlen, recordlen;
1109 
1110 	PMCDBG3(LOG,EXC,1,"po=%p pid=%d path=\"%s\"", po, pid, path);
1111 
1112 	pathlen   = strlen(path) + 1;	/* #bytes for the path */
1113 	recordlen = offsetof(struct pmclog_procexec, pl_pathname) + pathlen;
1114 	PMCLOG_RESERVE(po, PMCLOG_TYPE_PROCEXEC, recordlen);
1115 	PMCLOG_EMIT32(pid);
1116 	PMCLOG_EMIT32(pmid);
1117 	PMCLOG_EMITADDR(baseaddr);
1118 	PMCLOG_EMITADDR(dynaddr);
1119 	PMCLOG_EMITSTRING(path,pathlen);
1120 	PMCLOG_DESPATCH_SYNC(po);
1121 }
1122 
1123 /*
1124  * Log a process exit event (and accumulated pmc value) to the log file.
1125  */
1126 
1127 void
pmclog_process_procexit(struct pmc * pm,struct pmc_process * pp)1128 pmclog_process_procexit(struct pmc *pm, struct pmc_process *pp)
1129 {
1130 	int ri;
1131 	struct pmc_owner *po;
1132 
1133 	ri = PMC_TO_ROWINDEX(pm);
1134 	PMCDBG3(LOG,EXT,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
1135 	    pp->pp_pmcs[ri].pp_pmcval);
1136 
1137 	po = pm->pm_owner;
1138 
1139 	PMCLOG_RESERVE(po, PMCLOG_TYPE_PROCEXIT,
1140 	    sizeof(struct pmclog_procexit));
1141 	PMCLOG_EMIT32(pm->pm_id);
1142 	PMCLOG_EMIT32(pp->pp_proc->p_pid);
1143 	PMCLOG_EMIT64(pp->pp_pmcs[ri].pp_pmcval);
1144 	PMCLOG_DESPATCH(po);
1145 }
1146 
1147 /*
1148  * Log a fork event.
1149  */
1150 
1151 void
pmclog_process_procfork(struct pmc_owner * po,pid_t oldpid,pid_t newpid)1152 pmclog_process_procfork(struct pmc_owner *po, pid_t oldpid, pid_t newpid)
1153 {
1154 	PMCLOG_RESERVE(po, PMCLOG_TYPE_PROCFORK,
1155 	    sizeof(struct pmclog_procfork));
1156 	PMCLOG_EMIT32(oldpid);
1157 	PMCLOG_EMIT32(newpid);
1158 	PMCLOG_DESPATCH(po);
1159 }
1160 
1161 /*
1162  * Log a process exit event of the form suitable for system-wide PMCs.
1163  */
1164 
1165 void
pmclog_process_sysexit(struct pmc_owner * po,pid_t pid)1166 pmclog_process_sysexit(struct pmc_owner *po, pid_t pid)
1167 {
1168 	PMCLOG_RESERVE(po, PMCLOG_TYPE_SYSEXIT, sizeof(struct pmclog_sysexit));
1169 	PMCLOG_EMIT32(pid);
1170 	PMCLOG_DESPATCH(po);
1171 }
1172 
1173 void
pmclog_process_threadcreate(struct pmc_owner * po,struct thread * td,int sync)1174 pmclog_process_threadcreate(struct pmc_owner *po, struct thread *td, int sync)
1175 {
1176 	struct proc *p;
1177 
1178 	p = td->td_proc;
1179 	if (sync) {
1180 		PMCLOG_RESERVE(po, PMCLOG_TYPE_THR_CREATE,
1181 		    sizeof(struct pmclog_threadcreate));
1182 		PMCLOG_EMIT32(td->td_tid);
1183 		PMCLOG_EMIT32(p->p_pid);
1184 		PMCLOG_EMIT32(p->p_flag);
1185 		PMCLOG_EMIT32(0);
1186 		PMCLOG_EMITSTRING(td->td_name, MAXCOMLEN+1);
1187 		PMCLOG_DESPATCH_SYNC(po);
1188 	} else {
1189 		PMCLOG_RESERVE(po, PMCLOG_TYPE_THR_CREATE,
1190 		    sizeof(struct pmclog_threadcreate));
1191 		PMCLOG_EMIT32(td->td_tid);
1192 		PMCLOG_EMIT32(p->p_pid);
1193 		PMCLOG_EMIT32(p->p_flag);
1194 		PMCLOG_EMIT32(0);
1195 		PMCLOG_EMITSTRING(td->td_name, MAXCOMLEN+1);
1196 		PMCLOG_DESPATCH(po);
1197 	}
1198 }
1199 
1200 void
pmclog_process_threadexit(struct pmc_owner * po,struct thread * td)1201 pmclog_process_threadexit(struct pmc_owner *po, struct thread *td)
1202 {
1203 
1204 	PMCLOG_RESERVE(po, PMCLOG_TYPE_THR_EXIT,
1205 	    sizeof(struct pmclog_threadexit));
1206 	PMCLOG_EMIT32(td->td_tid);
1207 	PMCLOG_DESPATCH(po);
1208 }
1209 
1210 /*
1211  * Write a user log entry.
1212  */
1213 
1214 int
pmclog_process_userlog(struct pmc_owner * po,struct pmc_op_writelog * wl)1215 pmclog_process_userlog(struct pmc_owner *po, struct pmc_op_writelog *wl)
1216 {
1217 	int error;
1218 
1219 	PMCDBG2(LOG,WRI,1, "writelog po=%p ud=0x%x", po, wl->pm_userdata);
1220 
1221 	error = 0;
1222 
1223 	PMCLOG_RESERVE_WITH_ERROR(po, PMCLOG_TYPE_USERDATA,
1224 	    sizeof(struct pmclog_userdata));
1225 	PMCLOG_EMIT32(wl->pm_userdata);
1226 	PMCLOG_DESPATCH(po);
1227 
1228  error:
1229 	return (error);
1230 }
1231 
1232 /*
1233  * Initialization.
1234  *
1235  * Create a pool of log buffers and initialize mutexes.
1236  */
1237 
1238 void
pmclog_initialize(void)1239 pmclog_initialize(void)
1240 {
1241 	struct pmclog_buffer *plb;
1242 	int domain, ncpus, total;
1243 
1244 	if (pmclog_buffer_size <= 0 ||
1245 	    pmclog_buffer_size > PMC_LOG_BUFFER_SIZE_MAX) {
1246 		log(LOG_WARNING,
1247 		    "hwpmc: logbuffersize=%d must be greater than zero "
1248 		    "and less than or equal to %d, resetting to %d\n",
1249 		    pmclog_buffer_size, PMC_LOG_BUFFER_SIZE_MAX,
1250 		    PMC_LOG_BUFFER_SIZE);
1251 
1252 		pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
1253 	}
1254 
1255 	if (pmc_nlogbuffers_pcpu <= 0) {
1256 		log(LOG_WARNING,
1257 		    "hwpmc: nbuffers_pcpu=%d must be greater than zero, "
1258 		    "resetting to %d\n",
1259 		    pmc_nlogbuffers_pcpu, PMC_NLOGBUFFERS_PCPU);
1260 
1261 		pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
1262 	}
1263 
1264 	if (pmc_nlogbuffers_pcpu * pmclog_buffer_size >
1265 	    PMC_NLOGBUFFERS_PCPU_MEM_MAX) {
1266 		log(LOG_WARNING,
1267 		    "hwpmc: nbuffers_pcpu=%d * logbuffersize=%d exceeds "
1268 		    "%dMB per CPU limit, resetting to defaults (%d * %d)\n",
1269 		    pmc_nlogbuffers_pcpu, pmclog_buffer_size,
1270 		    PMC_NLOGBUFFERS_PCPU_MEM_MAX / 1024,
1271 		    PMC_NLOGBUFFERS_PCPU, PMC_LOG_BUFFER_SIZE);
1272 
1273 		pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
1274 		pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
1275 	}
1276 
1277 	for (domain = 0; domain < vm_ndomains; domain++) {
1278 		ncpus = pmc_dom_hdrs[domain]->pdbh_ncpus;
1279 		total = ncpus * pmc_nlogbuffers_pcpu;
1280 
1281 		plb = malloc_domainset(sizeof(struct pmclog_buffer) * total,
1282 		    M_PMC, DOMAINSET_PREF(domain), M_WAITOK | M_ZERO);
1283 		pmc_dom_hdrs[domain]->pdbh_plbs = plb;
1284 		for (; total > 0; total--, plb++) {
1285 			void *buf;
1286 
1287 			buf = malloc_domainset(1024 * pmclog_buffer_size, M_PMC,
1288 			    DOMAINSET_PREF(domain), M_WAITOK | M_ZERO);
1289 			PMCLOG_INIT_BUFFER_DESCRIPTOR(plb, buf, domain);
1290 			pmc_plb_rele_unlocked(plb);
1291 		}
1292 	}
1293 
1294 	mtx_init(&pmc_kthread_mtx, "pmc-kthread", "pmc-sleep", MTX_DEF);
1295 }
1296 
1297 /*
1298  * Shutdown logging.
1299  *
1300  * Destroy mutexes and release memory back the to free pool.
1301  */
1302 
1303 void
pmclog_shutdown(void)1304 pmclog_shutdown(void)
1305 {
1306 	struct pmclog_buffer *plb;
1307 	int domain;
1308 
1309 	mtx_destroy(&pmc_kthread_mtx);
1310 
1311 	for (domain = 0; domain < vm_ndomains; domain++) {
1312 		while ((plb = TAILQ_FIRST(&pmc_dom_hdrs[domain]->pdbh_head)) != NULL) {
1313 			TAILQ_REMOVE(&pmc_dom_hdrs[domain]->pdbh_head, plb, plb_next);
1314 			free(plb->plb_base, M_PMC);
1315 		}
1316 		free(pmc_dom_hdrs[domain]->pdbh_plbs, M_PMC);
1317 	}
1318 }
1319