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