1 /*-
2 * Copyright (c) 2005-2007 Joseph Koshy
3 * Copyright (c) 2007 The FreeBSD Foundation
4 * All rights reserved.
5 *
6 * Portions of this software were developed by A. Joseph Koshy under
7 * sponsorship from the FreeBSD Foundation and Google, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 */
31
32 /*
33 * Logging code for hwpmc(4)
34 */
35
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD: stable/10/sys/dev/hwpmc/hwpmc_logging.c 283884 2015-06-01 17:57:05Z jhb $");
38
39 #include <sys/param.h>
40 #if (__FreeBSD_version >= 1100000)
41 #include <sys/capsicum.h>
42 #else
43 #include <sys/capability.h>
44 #endif
45 #include <sys/file.h>
46 #include <sys/kernel.h>
47 #include <sys/kthread.h>
48 #include <sys/lock.h>
49 #include <sys/module.h>
50 #include <sys/mutex.h>
51 #include <sys/pmc.h>
52 #include <sys/pmckern.h>
53 #include <sys/pmclog.h>
54 #include <sys/proc.h>
55 #include <sys/signalvar.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
62 /*
63 * Sysctl tunables
64 */
65
66 SYSCTL_DECL(_kern_hwpmc);
67
68 /*
69 * kern.hwpmc.logbuffersize -- size of the per-cpu owner buffers.
70 */
71
72 static int pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
73 SYSCTL_INT(_kern_hwpmc, OID_AUTO, logbuffersize, CTLFLAG_RDTUN,
74 &pmclog_buffer_size, 0, "size of log buffers in kilobytes");
75
76 /*
77 * kern.hwpmc.nbuffer -- number of global log buffers
78 */
79
80 static int pmc_nlogbuffers = PMC_NLOGBUFFERS;
81 SYSCTL_INT(_kern_hwpmc, OID_AUTO, nbuffers, CTLFLAG_RDTUN,
82 &pmc_nlogbuffers, 0, "number of global log buffers");
83
84 /*
85 * Global log buffer list and associated spin lock.
86 */
87
88 TAILQ_HEAD(, pmclog_buffer) pmc_bufferlist =
89 TAILQ_HEAD_INITIALIZER(pmc_bufferlist);
90 static struct mtx pmc_bufferlist_mtx; /* spin lock */
91 static struct mtx pmc_kthread_mtx; /* sleep lock */
92
93 #define PMCLOG_INIT_BUFFER_DESCRIPTOR(D) do { \
94 const int __roundup = roundup(sizeof(*D), \
95 sizeof(uint32_t)); \
96 (D)->plb_fence = ((char *) (D)) + \
97 1024*pmclog_buffer_size; \
98 (D)->plb_base = (D)->plb_ptr = ((char *) (D)) + \
99 __roundup; \
100 } while (0)
101
102
103 /*
104 * Log file record constructors.
105 */
106 #define _PMCLOG_TO_HEADER(T,L) \
107 ((PMCLOG_HEADER_MAGIC << 24) | \
108 (PMCLOG_TYPE_ ## T << 16) | \
109 ((L) & 0xFFFF))
110
111 /* reserve LEN bytes of space and initialize the entry header */
112 #define _PMCLOG_RESERVE(PO,TYPE,LEN,ACTION) do { \
113 uint32_t *_le; \
114 int _len = roundup((LEN), sizeof(uint32_t)); \
115 if ((_le = pmclog_reserve((PO), _len)) == NULL) { \
116 ACTION; \
117 } \
118 *_le = _PMCLOG_TO_HEADER(TYPE,_len); \
119 _le += 3 /* skip over timestamp */
120
121 #define PMCLOG_RESERVE(P,T,L) _PMCLOG_RESERVE(P,T,L,return)
122 #define PMCLOG_RESERVE_WITH_ERROR(P,T,L) _PMCLOG_RESERVE(P,T,L, \
123 error=ENOMEM;goto error)
124
125 #define PMCLOG_EMIT32(V) do { *_le++ = (V); } while (0)
126 #define PMCLOG_EMIT64(V) do { \
127 *_le++ = (uint32_t) ((V) & 0xFFFFFFFF); \
128 *_le++ = (uint32_t) (((V) >> 32) & 0xFFFFFFFF); \
129 } while (0)
130
131
132 /* Emit a string. Caution: does NOT update _le, so needs to be last */
133 #define PMCLOG_EMITSTRING(S,L) do { bcopy((S), _le, (L)); } while (0)
134 #define PMCLOG_EMITNULLSTRING(L) do { bzero(_le, (L)); } while (0)
135
136 #define PMCLOG_DESPATCH(PO) \
137 pmclog_release((PO)); \
138 } while (0)
139
140
141 /*
142 * Assertions about the log file format.
143 */
144
145 CTASSERT(sizeof(struct pmclog_callchain) == 6*4 +
146 PMC_CALLCHAIN_DEPTH_MAX*sizeof(uintfptr_t));
147 CTASSERT(sizeof(struct pmclog_closelog) == 3*4);
148 CTASSERT(sizeof(struct pmclog_dropnotify) == 3*4);
149 CTASSERT(sizeof(struct pmclog_map_in) == PATH_MAX +
150 4*4 + sizeof(uintfptr_t));
151 CTASSERT(offsetof(struct pmclog_map_in,pl_pathname) ==
152 4*4 + sizeof(uintfptr_t));
153 CTASSERT(sizeof(struct pmclog_map_out) == 4*4 + 2*sizeof(uintfptr_t));
154 CTASSERT(sizeof(struct pmclog_pcsample) == 6*4 + sizeof(uintfptr_t));
155 CTASSERT(sizeof(struct pmclog_pmcallocate) == 6*4);
156 CTASSERT(sizeof(struct pmclog_pmcattach) == 5*4 + PATH_MAX);
157 CTASSERT(offsetof(struct pmclog_pmcattach,pl_pathname) == 5*4);
158 CTASSERT(sizeof(struct pmclog_pmcdetach) == 5*4);
159 CTASSERT(sizeof(struct pmclog_proccsw) == 5*4 + 8);
160 CTASSERT(sizeof(struct pmclog_procexec) == 5*4 + PATH_MAX +
161 sizeof(uintfptr_t));
162 CTASSERT(offsetof(struct pmclog_procexec,pl_pathname) == 5*4 +
163 sizeof(uintfptr_t));
164 CTASSERT(sizeof(struct pmclog_procexit) == 5*4 + 8);
165 CTASSERT(sizeof(struct pmclog_procfork) == 5*4);
166 CTASSERT(sizeof(struct pmclog_sysexit) == 4*4);
167 CTASSERT(sizeof(struct pmclog_userdata) == 4*4);
168
169 /*
170 * Log buffer structure
171 */
172
173 struct pmclog_buffer {
174 TAILQ_ENTRY(pmclog_buffer) plb_next;
175 char *plb_base;
176 char *plb_ptr;
177 char *plb_fence;
178 };
179
180 /*
181 * Prototypes
182 */
183
184 static int pmclog_get_buffer(struct pmc_owner *po);
185 static void pmclog_loop(void *arg);
186 static void pmclog_release(struct pmc_owner *po);
187 static uint32_t *pmclog_reserve(struct pmc_owner *po, int length);
188 static void pmclog_schedule_io(struct pmc_owner *po);
189 static void pmclog_stop_kthread(struct pmc_owner *po);
190
191 /*
192 * Helper functions
193 */
194
195 /*
196 * Get a log buffer
197 */
198
199 static int
pmclog_get_buffer(struct pmc_owner * po)200 pmclog_get_buffer(struct pmc_owner *po)
201 {
202 struct pmclog_buffer *plb;
203
204 mtx_assert(&po->po_mtx, MA_OWNED);
205
206 KASSERT(po->po_curbuf == NULL,
207 ("[pmclog,%d] po=%p current buffer still valid", __LINE__, po));
208
209 mtx_lock_spin(&pmc_bufferlist_mtx);
210 if ((plb = TAILQ_FIRST(&pmc_bufferlist)) != NULL)
211 TAILQ_REMOVE(&pmc_bufferlist, plb, plb_next);
212 mtx_unlock_spin(&pmc_bufferlist_mtx);
213
214 PMCDBG2(LOG,GTB,1, "po=%p plb=%p", po, plb);
215
216 #ifdef HWPMC_DEBUG
217 if (plb)
218 KASSERT(plb->plb_ptr == plb->plb_base &&
219 plb->plb_base < plb->plb_fence,
220 ("[pmclog,%d] po=%p buffer invariants: ptr=%p "
221 "base=%p fence=%p", __LINE__, po, plb->plb_ptr,
222 plb->plb_base, plb->plb_fence));
223 #endif
224
225 po->po_curbuf = plb;
226
227 /* update stats */
228 atomic_add_int(&pmc_stats.pm_buffer_requests, 1);
229 if (plb == NULL)
230 atomic_add_int(&pmc_stats.pm_buffer_requests_failed, 1);
231
232 return (plb ? 0 : ENOMEM);
233 }
234
235 /*
236 * Log handler loop.
237 *
238 * This function is executed by each pmc owner's helper thread.
239 */
240
241 static void
pmclog_loop(void * arg)242 pmclog_loop(void *arg)
243 {
244 int error;
245 struct pmc_owner *po;
246 struct pmclog_buffer *lb;
247 struct proc *p;
248 struct ucred *ownercred;
249 struct ucred *mycred;
250 struct thread *td;
251 struct uio auio;
252 struct iovec aiov;
253 size_t nbytes;
254
255 po = (struct pmc_owner *) arg;
256 p = po->po_owner;
257 td = curthread;
258 mycred = td->td_ucred;
259
260 PROC_LOCK(p);
261 ownercred = crhold(p->p_ucred);
262 PROC_UNLOCK(p);
263
264 PMCDBG2(LOG,INI,1, "po=%p kt=%p", po, po->po_kthread);
265 KASSERT(po->po_kthread == curthread->td_proc,
266 ("[pmclog,%d] proc mismatch po=%p po/kt=%p curproc=%p", __LINE__,
267 po, po->po_kthread, curthread->td_proc));
268
269 lb = NULL;
270
271
272 /*
273 * Loop waiting for I/O requests to be added to the owner
274 * struct's queue. The loop is exited when the log file
275 * is deconfigured.
276 */
277
278 mtx_lock(&pmc_kthread_mtx);
279
280 for (;;) {
281
282 /* check if we've been asked to exit */
283 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
284 break;
285
286 if (lb == NULL) { /* look for a fresh buffer to write */
287 mtx_lock_spin(&po->po_mtx);
288 if ((lb = TAILQ_FIRST(&po->po_logbuffers)) == NULL) {
289 mtx_unlock_spin(&po->po_mtx);
290
291 /* No more buffers and shutdown required. */
292 if (po->po_flags & PMC_PO_SHUTDOWN) {
293 mtx_unlock(&pmc_kthread_mtx);
294 /*
295 * Close the file to get PMCLOG_EOF
296 * error in pmclog(3).
297 */
298 fo_close(po->po_file, curthread);
299 mtx_lock(&pmc_kthread_mtx);
300 break;
301 }
302
303 (void) msleep(po, &pmc_kthread_mtx, PWAIT,
304 "pmcloop", 0);
305 continue;
306 }
307
308 TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
309 mtx_unlock_spin(&po->po_mtx);
310 }
311
312 mtx_unlock(&pmc_kthread_mtx);
313
314 /* process the request */
315 PMCDBG3(LOG,WRI,2, "po=%p base=%p ptr=%p", po,
316 lb->plb_base, lb->plb_ptr);
317 /* change our thread's credentials before issuing the I/O */
318
319 aiov.iov_base = lb->plb_base;
320 aiov.iov_len = nbytes = lb->plb_ptr - lb->plb_base;
321
322 auio.uio_iov = &aiov;
323 auio.uio_iovcnt = 1;
324 auio.uio_offset = -1;
325 auio.uio_resid = nbytes;
326 auio.uio_rw = UIO_WRITE;
327 auio.uio_segflg = UIO_SYSSPACE;
328 auio.uio_td = td;
329
330 /* switch thread credentials -- see kern_ktrace.c */
331 td->td_ucred = ownercred;
332 error = fo_write(po->po_file, &auio, ownercred, 0, td);
333 td->td_ucred = mycred;
334
335 if (error) {
336 /* XXX some errors are recoverable */
337 /* send a SIGIO to the owner and exit */
338 PROC_LOCK(p);
339 kern_psignal(p, SIGIO);
340 PROC_UNLOCK(p);
341
342 mtx_lock(&pmc_kthread_mtx);
343
344 po->po_error = error; /* save for flush log */
345
346 PMCDBG2(LOG,WRI,2, "po=%p error=%d", po, error);
347
348 break;
349 }
350
351 mtx_lock(&pmc_kthread_mtx);
352
353 /* put the used buffer back into the global pool */
354 PMCLOG_INIT_BUFFER_DESCRIPTOR(lb);
355
356 mtx_lock_spin(&pmc_bufferlist_mtx);
357 TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next);
358 mtx_unlock_spin(&pmc_bufferlist_mtx);
359
360 lb = NULL;
361 }
362
363 wakeup_one(po->po_kthread);
364 po->po_kthread = NULL;
365
366 mtx_unlock(&pmc_kthread_mtx);
367
368 /* return the current I/O buffer to the global pool */
369 if (lb) {
370 PMCLOG_INIT_BUFFER_DESCRIPTOR(lb);
371
372 mtx_lock_spin(&pmc_bufferlist_mtx);
373 TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next);
374 mtx_unlock_spin(&pmc_bufferlist_mtx);
375 }
376
377 /*
378 * Exit this thread, signalling the waiter
379 */
380
381 crfree(ownercred);
382
383 kproc_exit(0);
384 }
385
386 /*
387 * Release and log entry and schedule an I/O if needed.
388 */
389
390 static void
pmclog_release(struct pmc_owner * po)391 pmclog_release(struct pmc_owner *po)
392 {
393 KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base,
394 ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
395 po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base));
396 KASSERT(po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence,
397 ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
398 po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_fence));
399
400 /* schedule an I/O if we've filled a buffer */
401 if (po->po_curbuf->plb_ptr >= po->po_curbuf->plb_fence)
402 pmclog_schedule_io(po);
403
404 mtx_unlock_spin(&po->po_mtx);
405
406 PMCDBG1(LOG,REL,1, "po=%p", po);
407 }
408
409
410 /*
411 * Attempt to reserve 'length' bytes of space in an owner's log
412 * buffer. The function returns a pointer to 'length' bytes of space
413 * if there was enough space or returns NULL if no space was
414 * available. Non-null returns do so with the po mutex locked. The
415 * caller must invoke pmclog_release() on the pmc owner structure
416 * when done.
417 */
418
419 static uint32_t *
pmclog_reserve(struct pmc_owner * po,int length)420 pmclog_reserve(struct pmc_owner *po, int length)
421 {
422 uintptr_t newptr, oldptr;
423 uint32_t *lh;
424 struct timespec ts;
425
426 PMCDBG2(LOG,ALL,1, "po=%p len=%d", po, length);
427
428 KASSERT(length % sizeof(uint32_t) == 0,
429 ("[pmclog,%d] length not a multiple of word size", __LINE__));
430
431 mtx_lock_spin(&po->po_mtx);
432
433 /* No more data when shutdown in progress. */
434 if (po->po_flags & PMC_PO_SHUTDOWN) {
435 mtx_unlock_spin(&po->po_mtx);
436 return (NULL);
437 }
438
439 if (po->po_curbuf == NULL)
440 if (pmclog_get_buffer(po) != 0) {
441 mtx_unlock_spin(&po->po_mtx);
442 return (NULL);
443 }
444
445 KASSERT(po->po_curbuf != NULL,
446 ("[pmclog,%d] po=%p no current buffer", __LINE__, po));
447
448 KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base &&
449 po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence,
450 ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
451 __LINE__, po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base,
452 po->po_curbuf->plb_fence));
453
454 oldptr = (uintptr_t) po->po_curbuf->plb_ptr;
455 newptr = oldptr + length;
456
457 KASSERT(oldptr != (uintptr_t) NULL,
458 ("[pmclog,%d] po=%p Null log buffer pointer", __LINE__, po));
459
460 /*
461 * If we have space in the current buffer, return a pointer to
462 * available space with the PO structure locked.
463 */
464 if (newptr <= (uintptr_t) po->po_curbuf->plb_fence) {
465 po->po_curbuf->plb_ptr = (char *) newptr;
466 goto done;
467 }
468
469 /*
470 * Otherwise, schedule the current buffer for output and get a
471 * fresh buffer.
472 */
473 pmclog_schedule_io(po);
474
475 if (pmclog_get_buffer(po) != 0) {
476 mtx_unlock_spin(&po->po_mtx);
477 return (NULL);
478 }
479
480 KASSERT(po->po_curbuf != NULL,
481 ("[pmclog,%d] po=%p no current buffer", __LINE__, po));
482
483 KASSERT(po->po_curbuf->plb_ptr != NULL,
484 ("[pmclog,%d] null return from pmc_get_log_buffer", __LINE__));
485
486 KASSERT(po->po_curbuf->plb_ptr == po->po_curbuf->plb_base &&
487 po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence,
488 ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
489 __LINE__, po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base,
490 po->po_curbuf->plb_fence));
491
492 oldptr = (uintptr_t) po->po_curbuf->plb_ptr;
493
494 done:
495 lh = (uint32_t *) oldptr;
496 lh++; /* skip header */
497 getnanotime(&ts); /* fill in the timestamp */
498 *lh++ = ts.tv_sec & 0xFFFFFFFF;
499 *lh++ = ts.tv_nsec & 0xFFFFFFF;
500 return ((uint32_t *) oldptr);
501 }
502
503 /*
504 * Schedule an I/O.
505 *
506 * Transfer the current buffer to the helper kthread.
507 */
508
509 static void
pmclog_schedule_io(struct pmc_owner * po)510 pmclog_schedule_io(struct pmc_owner *po)
511 {
512 KASSERT(po->po_curbuf != NULL,
513 ("[pmclog,%d] schedule_io with null buffer po=%p", __LINE__, po));
514
515 KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base,
516 ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
517 po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base));
518 KASSERT(po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence,
519 ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
520 po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_fence));
521
522 PMCDBG1(LOG,SIO, 1, "po=%p", po);
523
524 mtx_assert(&po->po_mtx, MA_OWNED);
525
526 /*
527 * Add the current buffer to the tail of the buffer list and
528 * wakeup the helper.
529 */
530 TAILQ_INSERT_TAIL(&po->po_logbuffers, po->po_curbuf, plb_next);
531 po->po_curbuf = NULL;
532 wakeup_one(po);
533 }
534
535 /*
536 * Stop the helper kthread.
537 */
538
539 static void
pmclog_stop_kthread(struct pmc_owner * po)540 pmclog_stop_kthread(struct pmc_owner *po)
541 {
542 /*
543 * Close the file to force the thread out of fo_write,
544 * unset flag, wakeup the helper thread,
545 * wait for it to exit
546 */
547
548 if (po->po_file != NULL)
549 fo_close(po->po_file, curthread);
550
551 mtx_lock(&pmc_kthread_mtx);
552 po->po_flags &= ~PMC_PO_OWNS_LOGFILE;
553 wakeup_one(po);
554 if (po->po_kthread)
555 msleep(po->po_kthread, &pmc_kthread_mtx, PPAUSE, "pmckstp", 0);
556 mtx_unlock(&pmc_kthread_mtx);
557 }
558
559 /*
560 * Public functions
561 */
562
563 /*
564 * Configure a log file for pmc owner 'po'.
565 *
566 * Parameter 'logfd' is a file handle referencing an open file in the
567 * owner process. This file needs to have been opened for writing.
568 */
569
570 int
pmclog_configure_log(struct pmc_mdep * md,struct pmc_owner * po,int logfd)571 pmclog_configure_log(struct pmc_mdep *md, struct pmc_owner *po, int logfd)
572 {
573 int error;
574 struct proc *p;
575 cap_rights_t rights;
576 /*
577 * As long as it is possible to get a LOR between pmc_sx lock and
578 * proctree/allproc sx locks used for adding a new process, assure
579 * the former is not held here.
580 */
581 sx_assert(&pmc_sx, SA_UNLOCKED);
582 PMCDBG2(LOG,CFG,1, "config po=%p logfd=%d", po, logfd);
583
584 p = po->po_owner;
585
586 /* return EBUSY if a log file was already present */
587 if (po->po_flags & PMC_PO_OWNS_LOGFILE)
588 return (EBUSY);
589
590 KASSERT(po->po_kthread == NULL,
591 ("[pmclog,%d] po=%p kthread (%p) already present", __LINE__, po,
592 po->po_kthread));
593 KASSERT(po->po_file == NULL,
594 ("[pmclog,%d] po=%p file (%p) already present", __LINE__, po,
595 po->po_file));
596
597 /* get a reference to the file state */
598 error = fget_write(curthread, logfd,
599 cap_rights_init(&rights, CAP_WRITE), &po->po_file);
600 if (error)
601 goto error;
602
603 /* mark process as owning a log file */
604 po->po_flags |= PMC_PO_OWNS_LOGFILE;
605 error = kproc_create(pmclog_loop, po, &po->po_kthread,
606 RFHIGHPID, 0, "hwpmc: proc(%d)", p->p_pid);
607 if (error)
608 goto error;
609
610 /* mark process as using HWPMCs */
611 PROC_LOCK(p);
612 p->p_flag |= P_HWPMC;
613 PROC_UNLOCK(p);
614
615 /* create a log initialization entry */
616 PMCLOG_RESERVE_WITH_ERROR(po, INITIALIZE,
617 sizeof(struct pmclog_initialize));
618 PMCLOG_EMIT32(PMC_VERSION);
619 PMCLOG_EMIT32(md->pmd_cputype);
620 PMCLOG_DESPATCH(po);
621
622 return (0);
623
624 error:
625 /* shutdown the thread */
626 if (po->po_kthread)
627 pmclog_stop_kthread(po);
628
629 KASSERT(po->po_kthread == NULL, ("[pmclog,%d] po=%p kthread not "
630 "stopped", __LINE__, po));
631
632 if (po->po_file)
633 (void) fdrop(po->po_file, curthread);
634 po->po_file = NULL; /* clear file and error state */
635 po->po_error = 0;
636
637 return (error);
638 }
639
640
641 /*
642 * De-configure a log file. This will throw away any buffers queued
643 * for this owner process.
644 */
645
646 int
pmclog_deconfigure_log(struct pmc_owner * po)647 pmclog_deconfigure_log(struct pmc_owner *po)
648 {
649 int error;
650 struct pmclog_buffer *lb;
651
652 PMCDBG1(LOG,CFG,1, "de-config po=%p", po);
653
654 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
655 return (EINVAL);
656
657 KASSERT(po->po_sscount == 0,
658 ("[pmclog,%d] po=%p still owning SS PMCs", __LINE__, po));
659 KASSERT(po->po_file != NULL,
660 ("[pmclog,%d] po=%p no log file", __LINE__, po));
661
662 /* stop the kthread, this will reset the 'OWNS_LOGFILE' flag */
663 pmclog_stop_kthread(po);
664
665 KASSERT(po->po_kthread == NULL,
666 ("[pmclog,%d] po=%p kthread not stopped", __LINE__, po));
667
668 /* return all queued log buffers to the global pool */
669 while ((lb = TAILQ_FIRST(&po->po_logbuffers)) != NULL) {
670 TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
671 PMCLOG_INIT_BUFFER_DESCRIPTOR(lb);
672 mtx_lock_spin(&pmc_bufferlist_mtx);
673 TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next);
674 mtx_unlock_spin(&pmc_bufferlist_mtx);
675 }
676
677 /* return the 'current' buffer to the global pool */
678 if ((lb = po->po_curbuf) != NULL) {
679 PMCLOG_INIT_BUFFER_DESCRIPTOR(lb);
680 mtx_lock_spin(&pmc_bufferlist_mtx);
681 TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next);
682 mtx_unlock_spin(&pmc_bufferlist_mtx);
683 }
684
685 /* drop a reference to the fd */
686 error = fdrop(po->po_file, curthread);
687 po->po_file = NULL;
688 po->po_error = 0;
689
690 return (error);
691 }
692
693 /*
694 * Flush a process' log buffer.
695 */
696
697 int
pmclog_flush(struct pmc_owner * po)698 pmclog_flush(struct pmc_owner *po)
699 {
700 int error;
701 struct pmclog_buffer *lb;
702
703 PMCDBG1(LOG,FLS,1, "po=%p", po);
704
705 /*
706 * If there is a pending error recorded by the logger thread,
707 * return that.
708 */
709 if (po->po_error)
710 return (po->po_error);
711
712 error = 0;
713
714 /*
715 * Check that we do have an active log file.
716 */
717 mtx_lock(&pmc_kthread_mtx);
718 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) {
719 error = EINVAL;
720 goto error;
721 }
722
723 /*
724 * Schedule the current buffer if any and not empty.
725 */
726 mtx_lock_spin(&po->po_mtx);
727 lb = po->po_curbuf;
728 if (lb && lb->plb_ptr != lb->plb_base) {
729 pmclog_schedule_io(po);
730 } else
731 error = ENOBUFS;
732 mtx_unlock_spin(&po->po_mtx);
733
734 error:
735 mtx_unlock(&pmc_kthread_mtx);
736
737 return (error);
738 }
739
740 int
pmclog_close(struct pmc_owner * po)741 pmclog_close(struct pmc_owner *po)
742 {
743
744 PMCDBG1(LOG,CLO,1, "po=%p", po);
745
746 mtx_lock(&pmc_kthread_mtx);
747
748 /*
749 * Schedule the current buffer.
750 */
751 mtx_lock_spin(&po->po_mtx);
752 if (po->po_curbuf)
753 pmclog_schedule_io(po);
754 else
755 wakeup_one(po);
756 mtx_unlock_spin(&po->po_mtx);
757
758 /*
759 * Initiate shutdown: no new data queued,
760 * thread will close file on last block.
761 */
762 po->po_flags |= PMC_PO_SHUTDOWN;
763
764 mtx_unlock(&pmc_kthread_mtx);
765
766 return (0);
767 }
768
769 void
pmclog_process_callchain(struct pmc * pm,struct pmc_sample * ps)770 pmclog_process_callchain(struct pmc *pm, struct pmc_sample *ps)
771 {
772 int n, recordlen;
773 uint32_t flags;
774 struct pmc_owner *po;
775
776 PMCDBG3(LOG,SAM,1,"pm=%p pid=%d n=%d", pm, ps->ps_pid,
777 ps->ps_nsamples);
778
779 recordlen = offsetof(struct pmclog_callchain, pl_pc) +
780 ps->ps_nsamples * sizeof(uintfptr_t);
781 po = pm->pm_owner;
782 flags = PMC_CALLCHAIN_TO_CPUFLAGS(ps->ps_cpu,ps->ps_flags);
783 PMCLOG_RESERVE(po, CALLCHAIN, recordlen);
784 PMCLOG_EMIT32(ps->ps_pid);
785 PMCLOG_EMIT32(pm->pm_id);
786 PMCLOG_EMIT32(flags);
787 for (n = 0; n < ps->ps_nsamples; n++)
788 PMCLOG_EMITADDR(ps->ps_pc[n]);
789 PMCLOG_DESPATCH(po);
790 }
791
792 void
pmclog_process_closelog(struct pmc_owner * po)793 pmclog_process_closelog(struct pmc_owner *po)
794 {
795 PMCLOG_RESERVE(po,CLOSELOG,sizeof(struct pmclog_closelog));
796 PMCLOG_DESPATCH(po);
797 }
798
799 void
pmclog_process_dropnotify(struct pmc_owner * po)800 pmclog_process_dropnotify(struct pmc_owner *po)
801 {
802 PMCLOG_RESERVE(po,DROPNOTIFY,sizeof(struct pmclog_dropnotify));
803 PMCLOG_DESPATCH(po);
804 }
805
806 void
pmclog_process_map_in(struct pmc_owner * po,pid_t pid,uintfptr_t start,const char * path)807 pmclog_process_map_in(struct pmc_owner *po, pid_t pid, uintfptr_t start,
808 const char *path)
809 {
810 int pathlen, recordlen;
811
812 KASSERT(path != NULL, ("[pmclog,%d] map-in, null path", __LINE__));
813
814 pathlen = strlen(path) + 1; /* #bytes for path name */
815 recordlen = offsetof(struct pmclog_map_in, pl_pathname) +
816 pathlen;
817
818 PMCLOG_RESERVE(po, MAP_IN, recordlen);
819 PMCLOG_EMIT32(pid);
820 PMCLOG_EMITADDR(start);
821 PMCLOG_EMITSTRING(path,pathlen);
822 PMCLOG_DESPATCH(po);
823 }
824
825 void
pmclog_process_map_out(struct pmc_owner * po,pid_t pid,uintfptr_t start,uintfptr_t end)826 pmclog_process_map_out(struct pmc_owner *po, pid_t pid, uintfptr_t start,
827 uintfptr_t end)
828 {
829 KASSERT(start <= end, ("[pmclog,%d] start > end", __LINE__));
830
831 PMCLOG_RESERVE(po, MAP_OUT, sizeof(struct pmclog_map_out));
832 PMCLOG_EMIT32(pid);
833 PMCLOG_EMITADDR(start);
834 PMCLOG_EMITADDR(end);
835 PMCLOG_DESPATCH(po);
836 }
837
838 void
pmclog_process_pmcallocate(struct pmc * pm)839 pmclog_process_pmcallocate(struct pmc *pm)
840 {
841 struct pmc_owner *po;
842 struct pmc_soft *ps;
843
844 po = pm->pm_owner;
845
846 PMCDBG1(LOG,ALL,1, "pm=%p", pm);
847
848 if (PMC_TO_CLASS(pm) == PMC_CLASS_SOFT) {
849 PMCLOG_RESERVE(po, PMCALLOCATEDYN,
850 sizeof(struct pmclog_pmcallocatedyn));
851 PMCLOG_EMIT32(pm->pm_id);
852 PMCLOG_EMIT32(pm->pm_event);
853 PMCLOG_EMIT32(pm->pm_flags);
854 ps = pmc_soft_ev_acquire(pm->pm_event);
855 if (ps != NULL)
856 PMCLOG_EMITSTRING(ps->ps_ev.pm_ev_name,PMC_NAME_MAX);
857 else
858 PMCLOG_EMITNULLSTRING(PMC_NAME_MAX);
859 pmc_soft_ev_release(ps);
860 PMCLOG_DESPATCH(po);
861 } else {
862 PMCLOG_RESERVE(po, PMCALLOCATE,
863 sizeof(struct pmclog_pmcallocate));
864 PMCLOG_EMIT32(pm->pm_id);
865 PMCLOG_EMIT32(pm->pm_event);
866 PMCLOG_EMIT32(pm->pm_flags);
867 PMCLOG_DESPATCH(po);
868 }
869 }
870
871 void
pmclog_process_pmcattach(struct pmc * pm,pid_t pid,char * path)872 pmclog_process_pmcattach(struct pmc *pm, pid_t pid, char *path)
873 {
874 int pathlen, recordlen;
875 struct pmc_owner *po;
876
877 PMCDBG2(LOG,ATT,1,"pm=%p pid=%d", pm, pid);
878
879 po = pm->pm_owner;
880
881 pathlen = strlen(path) + 1; /* #bytes for the string */
882 recordlen = offsetof(struct pmclog_pmcattach, pl_pathname) + pathlen;
883
884 PMCLOG_RESERVE(po, PMCATTACH, recordlen);
885 PMCLOG_EMIT32(pm->pm_id);
886 PMCLOG_EMIT32(pid);
887 PMCLOG_EMITSTRING(path, pathlen);
888 PMCLOG_DESPATCH(po);
889 }
890
891 void
pmclog_process_pmcdetach(struct pmc * pm,pid_t pid)892 pmclog_process_pmcdetach(struct pmc *pm, pid_t pid)
893 {
894 struct pmc_owner *po;
895
896 PMCDBG2(LOG,ATT,1,"!pm=%p pid=%d", pm, pid);
897
898 po = pm->pm_owner;
899
900 PMCLOG_RESERVE(po, PMCDETACH, sizeof(struct pmclog_pmcdetach));
901 PMCLOG_EMIT32(pm->pm_id);
902 PMCLOG_EMIT32(pid);
903 PMCLOG_DESPATCH(po);
904 }
905
906 /*
907 * Log a context switch event to the log file.
908 */
909
910 void
pmclog_process_proccsw(struct pmc * pm,struct pmc_process * pp,pmc_value_t v)911 pmclog_process_proccsw(struct pmc *pm, struct pmc_process *pp, pmc_value_t v)
912 {
913 struct pmc_owner *po;
914
915 KASSERT(pm->pm_flags & PMC_F_LOG_PROCCSW,
916 ("[pmclog,%d] log-process-csw called gratuitously", __LINE__));
917
918 PMCDBG3(LOG,SWO,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
919 v);
920
921 po = pm->pm_owner;
922
923 PMCLOG_RESERVE(po, PROCCSW, sizeof(struct pmclog_proccsw));
924 PMCLOG_EMIT32(pm->pm_id);
925 PMCLOG_EMIT64(v);
926 PMCLOG_EMIT32(pp->pp_proc->p_pid);
927 PMCLOG_DESPATCH(po);
928 }
929
930 void
pmclog_process_procexec(struct pmc_owner * po,pmc_id_t pmid,pid_t pid,uintfptr_t startaddr,char * path)931 pmclog_process_procexec(struct pmc_owner *po, pmc_id_t pmid, pid_t pid,
932 uintfptr_t startaddr, char *path)
933 {
934 int pathlen, recordlen;
935
936 PMCDBG3(LOG,EXC,1,"po=%p pid=%d path=\"%s\"", po, pid, path);
937
938 pathlen = strlen(path) + 1; /* #bytes for the path */
939 recordlen = offsetof(struct pmclog_procexec, pl_pathname) + pathlen;
940
941 PMCLOG_RESERVE(po, PROCEXEC, recordlen);
942 PMCLOG_EMIT32(pid);
943 PMCLOG_EMITADDR(startaddr);
944 PMCLOG_EMIT32(pmid);
945 PMCLOG_EMITSTRING(path,pathlen);
946 PMCLOG_DESPATCH(po);
947 }
948
949 /*
950 * Log a process exit event (and accumulated pmc value) to the log file.
951 */
952
953 void
pmclog_process_procexit(struct pmc * pm,struct pmc_process * pp)954 pmclog_process_procexit(struct pmc *pm, struct pmc_process *pp)
955 {
956 int ri;
957 struct pmc_owner *po;
958
959 ri = PMC_TO_ROWINDEX(pm);
960 PMCDBG3(LOG,EXT,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
961 pp->pp_pmcs[ri].pp_pmcval);
962
963 po = pm->pm_owner;
964
965 PMCLOG_RESERVE(po, PROCEXIT, sizeof(struct pmclog_procexit));
966 PMCLOG_EMIT32(pm->pm_id);
967 PMCLOG_EMIT64(pp->pp_pmcs[ri].pp_pmcval);
968 PMCLOG_EMIT32(pp->pp_proc->p_pid);
969 PMCLOG_DESPATCH(po);
970 }
971
972 /*
973 * Log a fork event.
974 */
975
976 void
pmclog_process_procfork(struct pmc_owner * po,pid_t oldpid,pid_t newpid)977 pmclog_process_procfork(struct pmc_owner *po, pid_t oldpid, pid_t newpid)
978 {
979 PMCLOG_RESERVE(po, PROCFORK, sizeof(struct pmclog_procfork));
980 PMCLOG_EMIT32(oldpid);
981 PMCLOG_EMIT32(newpid);
982 PMCLOG_DESPATCH(po);
983 }
984
985 /*
986 * Log a process exit event of the form suitable for system-wide PMCs.
987 */
988
989 void
pmclog_process_sysexit(struct pmc_owner * po,pid_t pid)990 pmclog_process_sysexit(struct pmc_owner *po, pid_t pid)
991 {
992 PMCLOG_RESERVE(po, SYSEXIT, sizeof(struct pmclog_sysexit));
993 PMCLOG_EMIT32(pid);
994 PMCLOG_DESPATCH(po);
995 }
996
997 /*
998 * Write a user log entry.
999 */
1000
1001 int
pmclog_process_userlog(struct pmc_owner * po,struct pmc_op_writelog * wl)1002 pmclog_process_userlog(struct pmc_owner *po, struct pmc_op_writelog *wl)
1003 {
1004 int error;
1005
1006 PMCDBG2(LOG,WRI,1, "writelog po=%p ud=0x%x", po, wl->pm_userdata);
1007
1008 error = 0;
1009
1010 PMCLOG_RESERVE_WITH_ERROR(po, USERDATA,
1011 sizeof(struct pmclog_userdata));
1012 PMCLOG_EMIT32(wl->pm_userdata);
1013 PMCLOG_DESPATCH(po);
1014
1015 error:
1016 return (error);
1017 }
1018
1019 /*
1020 * Initialization.
1021 *
1022 * Create a pool of log buffers and initialize mutexes.
1023 */
1024
1025 void
pmclog_initialize()1026 pmclog_initialize()
1027 {
1028 int n;
1029 struct pmclog_buffer *plb;
1030
1031 if (pmclog_buffer_size <= 0) {
1032 (void) printf("hwpmc: tunable logbuffersize=%d must be "
1033 "greater than zero.\n", pmclog_buffer_size);
1034 pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
1035 }
1036
1037 if (pmc_nlogbuffers <= 0) {
1038 (void) printf("hwpmc: tunable nlogbuffers=%d must be greater "
1039 "than zero.\n", pmc_nlogbuffers);
1040 pmc_nlogbuffers = PMC_NLOGBUFFERS;
1041 }
1042
1043 /* create global pool of log buffers */
1044 for (n = 0; n < pmc_nlogbuffers; n++) {
1045 plb = malloc(1024 * pmclog_buffer_size, M_PMC,
1046 M_WAITOK|M_ZERO);
1047 PMCLOG_INIT_BUFFER_DESCRIPTOR(plb);
1048 TAILQ_INSERT_HEAD(&pmc_bufferlist, plb, plb_next);
1049 }
1050 mtx_init(&pmc_bufferlist_mtx, "pmc-buffer-list", "pmc-leaf",
1051 MTX_SPIN);
1052 mtx_init(&pmc_kthread_mtx, "pmc-kthread", "pmc-sleep", MTX_DEF);
1053 }
1054
1055 /*
1056 * Shutdown logging.
1057 *
1058 * Destroy mutexes and release memory back the to free pool.
1059 */
1060
1061 void
pmclog_shutdown()1062 pmclog_shutdown()
1063 {
1064 struct pmclog_buffer *plb;
1065
1066 mtx_destroy(&pmc_kthread_mtx);
1067 mtx_destroy(&pmc_bufferlist_mtx);
1068
1069 while ((plb = TAILQ_FIRST(&pmc_bufferlist)) != NULL) {
1070 TAILQ_REMOVE(&pmc_bufferlist, plb, plb_next);
1071 free(plb, M_PMC);
1072 }
1073 }
1074