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/11/sys/dev/hwpmc/hwpmc_logging.c 331722 2018-03-29 02:50:57Z eadler $"); 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/syscallsubr.h> 57#include <sys/sysctl.h> 58#include <sys/systm.h> 59#include <sys/uio.h> 60#include <sys/unistd.h> 61#include <sys/vnode.h> 62 63/* 64 * Sysctl tunables 65 */ 66 67SYSCTL_DECL(_kern_hwpmc); 68 69/* 70 * kern.hwpmc.logbuffersize -- size of the per-cpu owner buffers. 71 */ 72 73static int pmclog_buffer_size = PMC_LOG_BUFFER_SIZE; 74#if (__FreeBSD_version < 1100000) 75TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "logbuffersize", &pmclog_buffer_size); 76#endif 77SYSCTL_INT(_kern_hwpmc, OID_AUTO, logbuffersize, CTLFLAG_RDTUN, 78 &pmclog_buffer_size, 0, "size of log buffers in kilobytes"); 79 80/* 81 * kern.hwpmc.nbuffer -- number of global log buffers 82 */ 83 84static int pmc_nlogbuffers = PMC_NLOGBUFFERS; 85#if (__FreeBSD_version < 1100000) 86TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "nbuffers", &pmc_nlogbuffers); 87#endif 88SYSCTL_INT(_kern_hwpmc, OID_AUTO, nbuffers, CTLFLAG_RDTUN, 89 &pmc_nlogbuffers, 0, "number of global log buffers"); 90 91/* 92 * Global log buffer list and associated spin lock. 93 */ 94 95TAILQ_HEAD(, pmclog_buffer) pmc_bufferlist = 96 TAILQ_HEAD_INITIALIZER(pmc_bufferlist); 97static struct mtx pmc_bufferlist_mtx; /* spin lock */ 98static struct mtx pmc_kthread_mtx; /* sleep lock */ 99 100#define PMCLOG_INIT_BUFFER_DESCRIPTOR(D) do { \ 101 const int __roundup = roundup(sizeof(*D), \ 102 sizeof(uint32_t)); \ 103 (D)->plb_fence = ((char *) (D)) + \ 104 1024*pmclog_buffer_size; \ 105 (D)->plb_base = (D)->plb_ptr = ((char *) (D)) + \ 106 __roundup; \ 107 } while (0) 108 109 110/* 111 * Log file record constructors. 112 */ 113#define _PMCLOG_TO_HEADER(T,L) \ 114 ((PMCLOG_HEADER_MAGIC << 24) | \ 115 (PMCLOG_TYPE_ ## T << 16) | \ 116 ((L) & 0xFFFF)) 117 118/* reserve LEN bytes of space and initialize the entry header */ 119#define _PMCLOG_RESERVE(PO,TYPE,LEN,ACTION) do { \ 120 uint32_t *_le; \ 121 int _len = roundup((LEN), sizeof(uint32_t)); \ 122 if ((_le = pmclog_reserve((PO), _len)) == NULL) { \ 123 ACTION; \ 124 } \ 125 *_le = _PMCLOG_TO_HEADER(TYPE,_len); \ 126 _le += 3 /* skip over timestamp */ 127 128#define PMCLOG_RESERVE(P,T,L) _PMCLOG_RESERVE(P,T,L,return) 129#define PMCLOG_RESERVE_WITH_ERROR(P,T,L) _PMCLOG_RESERVE(P,T,L, \ 130 error=ENOMEM;goto error) 131 132#define PMCLOG_EMIT32(V) do { *_le++ = (V); } while (0) 133#define PMCLOG_EMIT64(V) do { \ 134 *_le++ = (uint32_t) ((V) & 0xFFFFFFFF); \ 135 *_le++ = (uint32_t) (((V) >> 32) & 0xFFFFFFFF); \ 136 } while (0) 137 138 139/* Emit a string. Caution: does NOT update _le, so needs to be last */ 140#define PMCLOG_EMITSTRING(S,L) do { bcopy((S), _le, (L)); } while (0) 141#define PMCLOG_EMITNULLSTRING(L) do { bzero(_le, (L)); } while (0) 142 143#define PMCLOG_DESPATCH(PO) \ 144 pmclog_release((PO)); \ 145 } while (0) 146 147 148/* 149 * Assertions about the log file format. 150 */ 151 152CTASSERT(sizeof(struct pmclog_callchain) == 6*4 + 153 PMC_CALLCHAIN_DEPTH_MAX*sizeof(uintfptr_t)); 154CTASSERT(sizeof(struct pmclog_closelog) == 3*4); 155CTASSERT(sizeof(struct pmclog_dropnotify) == 3*4); 156CTASSERT(sizeof(struct pmclog_map_in) == PATH_MAX + 157 4*4 + sizeof(uintfptr_t)); 158CTASSERT(offsetof(struct pmclog_map_in,pl_pathname) == 159 4*4 + sizeof(uintfptr_t)); 160CTASSERT(sizeof(struct pmclog_map_out) == 4*4 + 2*sizeof(uintfptr_t)); 161CTASSERT(sizeof(struct pmclog_pcsample) == 6*4 + sizeof(uintfptr_t)); 162CTASSERT(sizeof(struct pmclog_pmcallocate) == 6*4); 163CTASSERT(sizeof(struct pmclog_pmcattach) == 5*4 + PATH_MAX); 164CTASSERT(offsetof(struct pmclog_pmcattach,pl_pathname) == 5*4); 165CTASSERT(sizeof(struct pmclog_pmcdetach) == 5*4); 166CTASSERT(sizeof(struct pmclog_proccsw) == 5*4 + 8); 167CTASSERT(sizeof(struct pmclog_procexec) == 5*4 + PATH_MAX + 168 sizeof(uintfptr_t)); 169CTASSERT(offsetof(struct pmclog_procexec,pl_pathname) == 5*4 + 170 sizeof(uintfptr_t)); 171CTASSERT(sizeof(struct pmclog_procexit) == 5*4 + 8); 172CTASSERT(sizeof(struct pmclog_procfork) == 5*4); 173CTASSERT(sizeof(struct pmclog_sysexit) == 4*4); 174CTASSERT(sizeof(struct pmclog_userdata) == 4*4); 175 176/* 177 * Log buffer structure 178 */ 179 180struct pmclog_buffer { 181 TAILQ_ENTRY(pmclog_buffer) plb_next; 182 char *plb_base; 183 char *plb_ptr; 184 char *plb_fence; 185}; 186 187/* 188 * Prototypes 189 */ 190 191static int pmclog_get_buffer(struct pmc_owner *po); 192static void pmclog_loop(void *arg); 193static void pmclog_release(struct pmc_owner *po); 194static uint32_t *pmclog_reserve(struct pmc_owner *po, int length); 195static void pmclog_schedule_io(struct pmc_owner *po); 196static void pmclog_stop_kthread(struct pmc_owner *po); 197 198/* 199 * Helper functions 200 */ 201 202/* 203 * Get a log buffer 204 */ 205 206static int 207pmclog_get_buffer(struct pmc_owner *po) 208{ 209 struct pmclog_buffer *plb; 210 211 mtx_assert(&po->po_mtx, MA_OWNED); 212 213 KASSERT(po->po_curbuf == NULL, 214 ("[pmclog,%d] po=%p current buffer still valid", __LINE__, po)); 215 216 mtx_lock_spin(&pmc_bufferlist_mtx); 217 if ((plb = TAILQ_FIRST(&pmc_bufferlist)) != NULL) 218 TAILQ_REMOVE(&pmc_bufferlist, plb, plb_next); 219 mtx_unlock_spin(&pmc_bufferlist_mtx); 220 221 PMCDBG2(LOG,GTB,1, "po=%p plb=%p", po, plb); 222 223#ifdef HWPMC_DEBUG 224 if (plb) 225 KASSERT(plb->plb_ptr == plb->plb_base && 226 plb->plb_base < plb->plb_fence, 227 ("[pmclog,%d] po=%p buffer invariants: ptr=%p " 228 "base=%p fence=%p", __LINE__, po, plb->plb_ptr, 229 plb->plb_base, plb->plb_fence)); 230#endif 231 232 po->po_curbuf = plb; 233 234 /* update stats */ 235 atomic_add_int(&pmc_stats.pm_buffer_requests, 1); 236 if (plb == NULL) 237 atomic_add_int(&pmc_stats.pm_buffer_requests_failed, 1); 238 239 return (plb ? 0 : ENOMEM); 240} 241 242struct pmclog_proc_init_args { 243 struct proc *kthr; 244 struct pmc_owner *po; 245 bool exit; 246 bool acted; 247}; 248 249int 250pmclog_proc_create(struct thread *td, void **handlep) 251{ 252 struct pmclog_proc_init_args *ia; 253 int error; 254 255 ia = malloc(sizeof(*ia), M_TEMP, M_WAITOK | M_ZERO); 256 error = kproc_create(pmclog_loop, ia, &ia->kthr, 257 RFHIGHPID, 0, "hwpmc: proc(%d)", td->td_proc->p_pid); 258 if (error == 0) 259 *handlep = ia; 260 return (error); 261} 262 263void 264pmclog_proc_ignite(void *handle, struct pmc_owner *po) 265{ 266 struct pmclog_proc_init_args *ia; 267 268 ia = handle; 269 mtx_lock(&pmc_kthread_mtx); 270 MPASS(!ia->acted); 271 MPASS(ia->po == NULL); 272 MPASS(!ia->exit); 273 MPASS(ia->kthr != NULL); 274 if (po == NULL) { 275 ia->exit = true; 276 } else { 277 ia->po = po; 278 KASSERT(po->po_kthread == NULL, 279 ("[pmclog,%d] po=%p kthread (%p) already present", 280 __LINE__, po, po->po_kthread)); 281 po->po_kthread = ia->kthr; 282 } 283 wakeup(ia); 284 while (!ia->acted) 285 msleep(ia, &pmc_kthread_mtx, PWAIT, "pmclogw", 0); 286 mtx_unlock(&pmc_kthread_mtx); 287 free(ia, M_TEMP); 288} 289 290/* 291 * Log handler loop. 292 * 293 * This function is executed by each pmc owner's helper thread. 294 */ 295 296static void 297pmclog_loop(void *arg) 298{ 299 struct pmclog_proc_init_args *ia; 300 struct pmc_owner *po; 301 struct pmclog_buffer *lb; 302 struct proc *p; 303 struct ucred *ownercred; 304 struct ucred *mycred; 305 struct thread *td; 306 sigset_t unb; 307 struct uio auio; 308 struct iovec aiov; 309 size_t nbytes; 310 int error; 311 312 td = curthread; 313 314 SIGEMPTYSET(unb); 315 SIGADDSET(unb, SIGHUP); 316 (void)kern_sigprocmask(td, SIG_UNBLOCK, &unb, NULL, 0); 317 318 ia = arg; 319 MPASS(ia->kthr == curproc); 320 MPASS(!ia->acted); 321 mtx_lock(&pmc_kthread_mtx); 322 while (ia->po == NULL && !ia->exit) 323 msleep(ia, &pmc_kthread_mtx, PWAIT, "pmclogi", 0); 324 if (ia->exit) { 325 ia->acted = true; 326 wakeup(ia); 327 mtx_unlock(&pmc_kthread_mtx); 328 kproc_exit(0); 329 } 330 MPASS(ia->po != NULL); 331 po = ia->po; 332 ia->acted = true; 333 wakeup(ia); 334 mtx_unlock(&pmc_kthread_mtx); 335 ia = NULL; 336 337 p = po->po_owner; 338 mycred = td->td_ucred; 339 340 PROC_LOCK(p); 341 ownercred = crhold(p->p_ucred); 342 PROC_UNLOCK(p); 343 344 PMCDBG2(LOG,INI,1, "po=%p kt=%p", po, po->po_kthread); 345 KASSERT(po->po_kthread == curthread->td_proc, 346 ("[pmclog,%d] proc mismatch po=%p po/kt=%p curproc=%p", __LINE__, 347 po, po->po_kthread, curthread->td_proc)); 348 349 lb = NULL; 350 351 352 /* 353 * Loop waiting for I/O requests to be added to the owner 354 * struct's queue. The loop is exited when the log file 355 * is deconfigured. 356 */ 357 358 mtx_lock(&pmc_kthread_mtx); 359 360 for (;;) { 361 362 /* check if we've been asked to exit */ 363 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) 364 break; 365 366 if (lb == NULL) { /* look for a fresh buffer to write */ 367 mtx_lock_spin(&po->po_mtx); 368 if ((lb = TAILQ_FIRST(&po->po_logbuffers)) == NULL) { 369 mtx_unlock_spin(&po->po_mtx); 370 371 /* No more buffers and shutdown required. */ 372 if (po->po_flags & PMC_PO_SHUTDOWN) 373 break; 374 375 (void) msleep(po, &pmc_kthread_mtx, PWAIT, 376 "pmcloop", 0); 377 continue; 378 } 379 380 TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next); 381 mtx_unlock_spin(&po->po_mtx); 382 } 383 384 mtx_unlock(&pmc_kthread_mtx); 385 386 /* process the request */ 387 PMCDBG3(LOG,WRI,2, "po=%p base=%p ptr=%p", po, 388 lb->plb_base, lb->plb_ptr); 389 /* change our thread's credentials before issuing the I/O */ 390 391 aiov.iov_base = lb->plb_base; 392 aiov.iov_len = nbytes = lb->plb_ptr - lb->plb_base; 393 394 auio.uio_iov = &aiov; 395 auio.uio_iovcnt = 1; 396 auio.uio_offset = -1; 397 auio.uio_resid = nbytes; 398 auio.uio_rw = UIO_WRITE; 399 auio.uio_segflg = UIO_SYSSPACE; 400 auio.uio_td = td; 401 402 /* switch thread credentials -- see kern_ktrace.c */ 403 td->td_ucred = ownercred; 404 error = fo_write(po->po_file, &auio, ownercred, 0, td); 405 td->td_ucred = mycred; 406 407 if (error) { 408 /* XXX some errors are recoverable */ 409 /* send a SIGIO to the owner and exit */ 410 PROC_LOCK(p); 411 kern_psignal(p, SIGIO); 412 PROC_UNLOCK(p); 413 414 mtx_lock(&pmc_kthread_mtx); 415 416 po->po_error = error; /* save for flush log */ 417 418 PMCDBG2(LOG,WRI,2, "po=%p error=%d", po, error); 419 420 break; 421 } 422 423 mtx_lock(&pmc_kthread_mtx); 424 425 /* put the used buffer back into the global pool */ 426 PMCLOG_INIT_BUFFER_DESCRIPTOR(lb); 427 428 mtx_lock_spin(&pmc_bufferlist_mtx); 429 TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next); 430 mtx_unlock_spin(&pmc_bufferlist_mtx); 431 432 lb = NULL; 433 } 434 435 wakeup_one(po->po_kthread); 436 po->po_kthread = NULL; 437 438 mtx_unlock(&pmc_kthread_mtx); 439 440 /* return the current I/O buffer to the global pool */ 441 if (lb) { 442 PMCLOG_INIT_BUFFER_DESCRIPTOR(lb); 443 444 mtx_lock_spin(&pmc_bufferlist_mtx); 445 TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next); 446 mtx_unlock_spin(&pmc_bufferlist_mtx); 447 } 448 449 /* 450 * Exit this thread, signalling the waiter 451 */ 452 453 crfree(ownercred); 454 455 kproc_exit(0); 456} 457 458/* 459 * Release and log entry and schedule an I/O if needed. 460 */ 461 462static void 463pmclog_release(struct pmc_owner *po) 464{ 465 KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base, 466 ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__, 467 po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base)); 468 KASSERT(po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence, 469 ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__, 470 po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_fence)); 471 472 /* schedule an I/O if we've filled a buffer */ 473 if (po->po_curbuf->plb_ptr >= po->po_curbuf->plb_fence) 474 pmclog_schedule_io(po); 475 476 mtx_unlock_spin(&po->po_mtx); 477 478 PMCDBG1(LOG,REL,1, "po=%p", po); 479} 480 481 482/* 483 * Attempt to reserve 'length' bytes of space in an owner's log 484 * buffer. The function returns a pointer to 'length' bytes of space 485 * if there was enough space or returns NULL if no space was 486 * available. Non-null returns do so with the po mutex locked. The 487 * caller must invoke pmclog_release() on the pmc owner structure 488 * when done. 489 */ 490 491static uint32_t * 492pmclog_reserve(struct pmc_owner *po, int length) 493{ 494 uintptr_t newptr, oldptr; 495 uint32_t *lh; 496 struct timespec ts; 497 498 PMCDBG2(LOG,ALL,1, "po=%p len=%d", po, length); 499 500 KASSERT(length % sizeof(uint32_t) == 0, 501 ("[pmclog,%d] length not a multiple of word size", __LINE__)); 502 503 mtx_lock_spin(&po->po_mtx); 504 505 /* No more data when shutdown in progress. */ 506 if (po->po_flags & PMC_PO_SHUTDOWN) { 507 mtx_unlock_spin(&po->po_mtx); 508 return (NULL); 509 } 510 511 if (po->po_curbuf == NULL) 512 if (pmclog_get_buffer(po) != 0) { 513 mtx_unlock_spin(&po->po_mtx); 514 return (NULL); 515 } 516 517 KASSERT(po->po_curbuf != NULL, 518 ("[pmclog,%d] po=%p no current buffer", __LINE__, po)); 519 520 KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base && 521 po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence, 522 ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p", 523 __LINE__, po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base, 524 po->po_curbuf->plb_fence)); 525 526 oldptr = (uintptr_t) po->po_curbuf->plb_ptr; 527 newptr = oldptr + length; 528 529 KASSERT(oldptr != (uintptr_t) NULL, 530 ("[pmclog,%d] po=%p Null log buffer pointer", __LINE__, po)); 531 532 /* 533 * If we have space in the current buffer, return a pointer to 534 * available space with the PO structure locked. 535 */ 536 if (newptr <= (uintptr_t) po->po_curbuf->plb_fence) { 537 po->po_curbuf->plb_ptr = (char *) newptr; 538 goto done; 539 } 540 541 /* 542 * Otherwise, schedule the current buffer for output and get a 543 * fresh buffer. 544 */ 545 pmclog_schedule_io(po); 546 547 if (pmclog_get_buffer(po) != 0) { 548 mtx_unlock_spin(&po->po_mtx); 549 return (NULL); 550 } 551 552 KASSERT(po->po_curbuf != NULL, 553 ("[pmclog,%d] po=%p no current buffer", __LINE__, po)); 554 555 KASSERT(po->po_curbuf->plb_ptr != NULL, 556 ("[pmclog,%d] null return from pmc_get_log_buffer", __LINE__)); 557 558 KASSERT(po->po_curbuf->plb_ptr == po->po_curbuf->plb_base && 559 po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence, 560 ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p", 561 __LINE__, po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base, 562 po->po_curbuf->plb_fence)); 563 564 oldptr = (uintptr_t) po->po_curbuf->plb_ptr; 565 566 done: 567 lh = (uint32_t *) oldptr; 568 lh++; /* skip header */ 569 getnanotime(&ts); /* fill in the timestamp */ 570 *lh++ = ts.tv_sec & 0xFFFFFFFF; 571 *lh++ = ts.tv_nsec & 0xFFFFFFF; 572 return ((uint32_t *) oldptr); 573} 574 575/* 576 * Schedule an I/O. 577 * 578 * Transfer the current buffer to the helper kthread. 579 */ 580 581static void 582pmclog_schedule_io(struct pmc_owner *po) 583{ 584 KASSERT(po->po_curbuf != NULL, 585 ("[pmclog,%d] schedule_io with null buffer po=%p", __LINE__, po)); 586 587 KASSERT(po->po_curbuf->plb_ptr >= po->po_curbuf->plb_base, 588 ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__, 589 po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_base)); 590 KASSERT(po->po_curbuf->plb_ptr <= po->po_curbuf->plb_fence, 591 ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__, 592 po, po->po_curbuf->plb_ptr, po->po_curbuf->plb_fence)); 593 594 PMCDBG1(LOG,SIO, 1, "po=%p", po); 595 596 mtx_assert(&po->po_mtx, MA_OWNED); 597 598 /* 599 * Add the current buffer to the tail of the buffer list and 600 * wakeup the helper. 601 */ 602 TAILQ_INSERT_TAIL(&po->po_logbuffers, po->po_curbuf, plb_next); 603 po->po_curbuf = NULL; 604 wakeup_one(po); 605} 606 607/* 608 * Stop the helper kthread. 609 */ 610 611static void 612pmclog_stop_kthread(struct pmc_owner *po) 613{ 614 615 mtx_lock(&pmc_kthread_mtx); 616 po->po_flags &= ~PMC_PO_OWNS_LOGFILE; 617 if (po->po_kthread != NULL) { 618 PROC_LOCK(po->po_kthread); 619 kern_psignal(po->po_kthread, SIGHUP); 620 PROC_UNLOCK(po->po_kthread); 621 } 622 wakeup_one(po); 623 while (po->po_kthread) 624 msleep(po->po_kthread, &pmc_kthread_mtx, PPAUSE, "pmckstp", 0); 625 mtx_unlock(&pmc_kthread_mtx); 626} 627 628/* 629 * Public functions 630 */ 631 632/* 633 * Configure a log file for pmc owner 'po'. 634 * 635 * Parameter 'logfd' is a file handle referencing an open file in the 636 * owner process. This file needs to have been opened for writing. 637 */ 638 639int 640pmclog_configure_log(struct pmc_mdep *md, struct pmc_owner *po, int logfd) 641{ 642 struct proc *p; 643 cap_rights_t rights; 644 int error; 645 646 sx_assert(&pmc_sx, SA_XLOCKED); 647 PMCDBG2(LOG,CFG,1, "config po=%p logfd=%d", po, logfd); 648 649 p = po->po_owner; 650 651 /* return EBUSY if a log file was already present */ 652 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 653 return (EBUSY); 654 655 KASSERT(po->po_file == NULL, 656 ("[pmclog,%d] po=%p file (%p) already present", __LINE__, po, 657 po->po_file)); 658 659 /* get a reference to the file state */ 660 error = fget_write(curthread, logfd, 661 cap_rights_init(&rights, CAP_WRITE), &po->po_file); 662 if (error) 663 goto error; 664 665 /* mark process as owning a log file */ 666 po->po_flags |= PMC_PO_OWNS_LOGFILE; 667 668 /* mark process as using HWPMCs */ 669 PROC_LOCK(p); 670 p->p_flag |= P_HWPMC; 671 PROC_UNLOCK(p); 672 673 /* create a log initialization entry */ 674 PMCLOG_RESERVE_WITH_ERROR(po, INITIALIZE, 675 sizeof(struct pmclog_initialize)); 676 PMCLOG_EMIT32(PMC_VERSION); 677 PMCLOG_EMIT32(md->pmd_cputype); 678 PMCLOG_DESPATCH(po); 679 680 return (0); 681 682 error: 683 KASSERT(po->po_kthread == NULL, ("[pmclog,%d] po=%p kthread not " 684 "stopped", __LINE__, po)); 685 686 if (po->po_file) 687 (void) fdrop(po->po_file, curthread); 688 po->po_file = NULL; /* clear file and error state */ 689 po->po_error = 0; 690 po->po_flags &= ~PMC_PO_OWNS_LOGFILE; 691 692 return (error); 693} 694 695 696/* 697 * De-configure a log file. This will throw away any buffers queued 698 * for this owner process. 699 */ 700 701int 702pmclog_deconfigure_log(struct pmc_owner *po) 703{ 704 int error; 705 struct pmclog_buffer *lb; 706 707 PMCDBG1(LOG,CFG,1, "de-config po=%p", po); 708 709 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) 710 return (EINVAL); 711 712 KASSERT(po->po_sscount == 0, 713 ("[pmclog,%d] po=%p still owning SS PMCs", __LINE__, po)); 714 KASSERT(po->po_file != NULL, 715 ("[pmclog,%d] po=%p no log file", __LINE__, po)); 716 717 /* stop the kthread, this will reset the 'OWNS_LOGFILE' flag */ 718 pmclog_stop_kthread(po); 719 720 KASSERT(po->po_kthread == NULL, 721 ("[pmclog,%d] po=%p kthread not stopped", __LINE__, po)); 722 723 /* return all queued log buffers to the global pool */ 724 while ((lb = TAILQ_FIRST(&po->po_logbuffers)) != NULL) { 725 TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next); 726 PMCLOG_INIT_BUFFER_DESCRIPTOR(lb); 727 mtx_lock_spin(&pmc_bufferlist_mtx); 728 TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next); 729 mtx_unlock_spin(&pmc_bufferlist_mtx); 730 } 731 732 /* return the 'current' buffer to the global pool */ 733 if ((lb = po->po_curbuf) != NULL) { 734 PMCLOG_INIT_BUFFER_DESCRIPTOR(lb); 735 mtx_lock_spin(&pmc_bufferlist_mtx); 736 TAILQ_INSERT_HEAD(&pmc_bufferlist, lb, plb_next); 737 mtx_unlock_spin(&pmc_bufferlist_mtx); 738 } 739 740 /* drop a reference to the fd */ 741 if (po->po_file != NULL) { 742 error = fdrop(po->po_file, curthread); 743 po->po_file = NULL; 744 } else 745 error = 0; 746 po->po_error = 0; 747 748 return (error); 749} 750 751/* 752 * Flush a process' log buffer. 753 */ 754 755int 756pmclog_flush(struct pmc_owner *po) 757{ 758 int error; 759 struct pmclog_buffer *lb; 760 761 PMCDBG1(LOG,FLS,1, "po=%p", po); 762 763 /* 764 * If there is a pending error recorded by the logger thread, 765 * return that. 766 */ 767 if (po->po_error) 768 return (po->po_error); 769 770 error = 0; 771 772 /* 773 * Check that we do have an active log file. 774 */ 775 mtx_lock(&pmc_kthread_mtx); 776 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) { 777 error = EINVAL; 778 goto error; 779 } 780 781 /* 782 * Schedule the current buffer if any and not empty. 783 */ 784 mtx_lock_spin(&po->po_mtx); 785 lb = po->po_curbuf; 786 if (lb && lb->plb_ptr != lb->plb_base) { 787 pmclog_schedule_io(po); 788 } else 789 error = ENOBUFS; 790 mtx_unlock_spin(&po->po_mtx); 791 792 error: 793 mtx_unlock(&pmc_kthread_mtx); 794 795 return (error); 796} 797 798int 799pmclog_close(struct pmc_owner *po) 800{ 801 802 PMCDBG1(LOG,CLO,1, "po=%p", po); 803 804 pmclog_process_closelog(po); 805 806 mtx_lock(&pmc_kthread_mtx); 807 808 /* 809 * Schedule the current buffer. 810 */ 811 mtx_lock_spin(&po->po_mtx); 812 if (po->po_curbuf) 813 pmclog_schedule_io(po); 814 else 815 wakeup_one(po); 816 mtx_unlock_spin(&po->po_mtx); 817 818 /* 819 * Initiate shutdown: no new data queued, 820 * thread will close file on last block. 821 */ 822 po->po_flags |= PMC_PO_SHUTDOWN; 823 824 mtx_unlock(&pmc_kthread_mtx); 825 826 return (0); 827} 828 829void 830pmclog_process_callchain(struct pmc *pm, struct pmc_sample *ps) 831{ 832 int n, recordlen; 833 uint32_t flags; 834 struct pmc_owner *po; 835 836 PMCDBG3(LOG,SAM,1,"pm=%p pid=%d n=%d", pm, ps->ps_pid, 837 ps->ps_nsamples); 838 839 recordlen = offsetof(struct pmclog_callchain, pl_pc) + 840 ps->ps_nsamples * sizeof(uintfptr_t); 841 po = pm->pm_owner; 842 flags = PMC_CALLCHAIN_TO_CPUFLAGS(ps->ps_cpu,ps->ps_flags); 843 PMCLOG_RESERVE(po, CALLCHAIN, recordlen); 844 PMCLOG_EMIT32(ps->ps_pid); 845 PMCLOG_EMIT32(pm->pm_id); 846 PMCLOG_EMIT32(flags); 847 for (n = 0; n < ps->ps_nsamples; n++) 848 PMCLOG_EMITADDR(ps->ps_pc[n]); 849 PMCLOG_DESPATCH(po); 850} 851 852void 853pmclog_process_closelog(struct pmc_owner *po) 854{ 855 PMCLOG_RESERVE(po,CLOSELOG,sizeof(struct pmclog_closelog)); 856 PMCLOG_DESPATCH(po); 857} 858 859void 860pmclog_process_dropnotify(struct pmc_owner *po) 861{ 862 PMCLOG_RESERVE(po,DROPNOTIFY,sizeof(struct pmclog_dropnotify)); 863 PMCLOG_DESPATCH(po); 864} 865 866void 867pmclog_process_map_in(struct pmc_owner *po, pid_t pid, uintfptr_t start, 868 const char *path) 869{ 870 int pathlen, recordlen; 871 872 KASSERT(path != NULL, ("[pmclog,%d] map-in, null path", __LINE__)); 873 874 pathlen = strlen(path) + 1; /* #bytes for path name */ 875 recordlen = offsetof(struct pmclog_map_in, pl_pathname) + 876 pathlen; 877 878 PMCLOG_RESERVE(po, MAP_IN, recordlen); 879 PMCLOG_EMIT32(pid); 880 PMCLOG_EMITADDR(start); 881 PMCLOG_EMITSTRING(path,pathlen); 882 PMCLOG_DESPATCH(po); 883} 884 885void 886pmclog_process_map_out(struct pmc_owner *po, pid_t pid, uintfptr_t start, 887 uintfptr_t end) 888{ 889 KASSERT(start <= end, ("[pmclog,%d] start > end", __LINE__)); 890 891 PMCLOG_RESERVE(po, MAP_OUT, sizeof(struct pmclog_map_out)); 892 PMCLOG_EMIT32(pid); 893 PMCLOG_EMITADDR(start); 894 PMCLOG_EMITADDR(end); 895 PMCLOG_DESPATCH(po); 896} 897 898void 899pmclog_process_pmcallocate(struct pmc *pm) 900{ 901 struct pmc_owner *po; 902 struct pmc_soft *ps; 903 904 po = pm->pm_owner; 905 906 PMCDBG1(LOG,ALL,1, "pm=%p", pm); 907 908 if (PMC_TO_CLASS(pm) == PMC_CLASS_SOFT) { 909 PMCLOG_RESERVE(po, PMCALLOCATEDYN, 910 sizeof(struct pmclog_pmcallocatedyn)); 911 PMCLOG_EMIT32(pm->pm_id); 912 PMCLOG_EMIT32(pm->pm_event); 913 PMCLOG_EMIT32(pm->pm_flags); 914 ps = pmc_soft_ev_acquire(pm->pm_event); 915 if (ps != NULL) 916 PMCLOG_EMITSTRING(ps->ps_ev.pm_ev_name,PMC_NAME_MAX); 917 else 918 PMCLOG_EMITNULLSTRING(PMC_NAME_MAX); 919 pmc_soft_ev_release(ps); 920 PMCLOG_DESPATCH(po); 921 } else { 922 PMCLOG_RESERVE(po, PMCALLOCATE, 923 sizeof(struct pmclog_pmcallocate)); 924 PMCLOG_EMIT32(pm->pm_id); 925 PMCLOG_EMIT32(pm->pm_event); 926 PMCLOG_EMIT32(pm->pm_flags); 927 PMCLOG_DESPATCH(po); 928 } 929} 930 931void 932pmclog_process_pmcattach(struct pmc *pm, pid_t pid, char *path) 933{ 934 int pathlen, recordlen; 935 struct pmc_owner *po; 936 937 PMCDBG2(LOG,ATT,1,"pm=%p pid=%d", pm, pid); 938 939 po = pm->pm_owner; 940 941 pathlen = strlen(path) + 1; /* #bytes for the string */ 942 recordlen = offsetof(struct pmclog_pmcattach, pl_pathname) + pathlen; 943 944 PMCLOG_RESERVE(po, PMCATTACH, recordlen); 945 PMCLOG_EMIT32(pm->pm_id); 946 PMCLOG_EMIT32(pid); 947 PMCLOG_EMITSTRING(path, pathlen); 948 PMCLOG_DESPATCH(po); 949} 950 951void 952pmclog_process_pmcdetach(struct pmc *pm, pid_t pid) 953{ 954 struct pmc_owner *po; 955 956 PMCDBG2(LOG,ATT,1,"!pm=%p pid=%d", pm, pid); 957 958 po = pm->pm_owner; 959 960 PMCLOG_RESERVE(po, PMCDETACH, sizeof(struct pmclog_pmcdetach)); 961 PMCLOG_EMIT32(pm->pm_id); 962 PMCLOG_EMIT32(pid); 963 PMCLOG_DESPATCH(po); 964} 965 966/* 967 * Log a context switch event to the log file. 968 */ 969 970void 971pmclog_process_proccsw(struct pmc *pm, struct pmc_process *pp, pmc_value_t v) 972{ 973 struct pmc_owner *po; 974 975 KASSERT(pm->pm_flags & PMC_F_LOG_PROCCSW, 976 ("[pmclog,%d] log-process-csw called gratuitously", __LINE__)); 977 978 PMCDBG3(LOG,SWO,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid, 979 v); 980 981 po = pm->pm_owner; 982 983 PMCLOG_RESERVE(po, PROCCSW, sizeof(struct pmclog_proccsw)); 984 PMCLOG_EMIT32(pm->pm_id); 985 PMCLOG_EMIT64(v); 986 PMCLOG_EMIT32(pp->pp_proc->p_pid); 987 PMCLOG_DESPATCH(po); 988} 989 990void 991pmclog_process_procexec(struct pmc_owner *po, pmc_id_t pmid, pid_t pid, 992 uintfptr_t startaddr, char *path) 993{ 994 int pathlen, recordlen; 995 996 PMCDBG3(LOG,EXC,1,"po=%p pid=%d path=\"%s\"", po, pid, path); 997 998 pathlen = strlen(path) + 1; /* #bytes for the path */ 999 recordlen = offsetof(struct pmclog_procexec, pl_pathname) + pathlen; 1000 1001 PMCLOG_RESERVE(po, PROCEXEC, recordlen); 1002 PMCLOG_EMIT32(pid); 1003 PMCLOG_EMITADDR(startaddr); 1004 PMCLOG_EMIT32(pmid); 1005 PMCLOG_EMITSTRING(path,pathlen); 1006 PMCLOG_DESPATCH(po); 1007} 1008 1009/* 1010 * Log a process exit event (and accumulated pmc value) to the log file. 1011 */ 1012 1013void 1014pmclog_process_procexit(struct pmc *pm, struct pmc_process *pp) 1015{ 1016 int ri; 1017 struct pmc_owner *po; 1018 1019 ri = PMC_TO_ROWINDEX(pm); 1020 PMCDBG3(LOG,EXT,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid, 1021 pp->pp_pmcs[ri].pp_pmcval); 1022 1023 po = pm->pm_owner; 1024 1025 PMCLOG_RESERVE(po, PROCEXIT, sizeof(struct pmclog_procexit)); 1026 PMCLOG_EMIT32(pm->pm_id); 1027 PMCLOG_EMIT64(pp->pp_pmcs[ri].pp_pmcval); 1028 PMCLOG_EMIT32(pp->pp_proc->p_pid); 1029 PMCLOG_DESPATCH(po); 1030} 1031 1032/* 1033 * Log a fork event. 1034 */ 1035 1036void 1037pmclog_process_procfork(struct pmc_owner *po, pid_t oldpid, pid_t newpid) 1038{ 1039 PMCLOG_RESERVE(po, PROCFORK, sizeof(struct pmclog_procfork)); 1040 PMCLOG_EMIT32(oldpid); 1041 PMCLOG_EMIT32(newpid); 1042 PMCLOG_DESPATCH(po); 1043} 1044 1045/* 1046 * Log a process exit event of the form suitable for system-wide PMCs. 1047 */ 1048 1049void 1050pmclog_process_sysexit(struct pmc_owner *po, pid_t pid) 1051{ 1052 PMCLOG_RESERVE(po, SYSEXIT, sizeof(struct pmclog_sysexit)); 1053 PMCLOG_EMIT32(pid); 1054 PMCLOG_DESPATCH(po); 1055} 1056 1057/* 1058 * Write a user log entry. 1059 */ 1060 1061int 1062pmclog_process_userlog(struct pmc_owner *po, struct pmc_op_writelog *wl) 1063{ 1064 int error; 1065 1066 PMCDBG2(LOG,WRI,1, "writelog po=%p ud=0x%x", po, wl->pm_userdata); 1067 1068 error = 0; 1069 1070 PMCLOG_RESERVE_WITH_ERROR(po, USERDATA, 1071 sizeof(struct pmclog_userdata)); 1072 PMCLOG_EMIT32(wl->pm_userdata); 1073 PMCLOG_DESPATCH(po); 1074 1075 error: 1076 return (error); 1077} 1078 1079/* 1080 * Initialization. 1081 * 1082 * Create a pool of log buffers and initialize mutexes. 1083 */ 1084 1085void 1086pmclog_initialize() 1087{ 1088 int n; 1089 struct pmclog_buffer *plb; 1090 1091 if (pmclog_buffer_size <= 0) { 1092 (void) printf("hwpmc: tunable logbuffersize=%d must be " 1093 "greater than zero.\n", pmclog_buffer_size); 1094 pmclog_buffer_size = PMC_LOG_BUFFER_SIZE; 1095 } 1096 1097 if (pmc_nlogbuffers <= 0) { 1098 (void) printf("hwpmc: tunable nlogbuffers=%d must be greater " 1099 "than zero.\n", pmc_nlogbuffers); 1100 pmc_nlogbuffers = PMC_NLOGBUFFERS; 1101 } 1102 1103 /* create global pool of log buffers */ 1104 for (n = 0; n < pmc_nlogbuffers; n++) { 1105 plb = malloc(1024 * pmclog_buffer_size, M_PMC, 1106 M_WAITOK|M_ZERO); 1107 PMCLOG_INIT_BUFFER_DESCRIPTOR(plb); 1108 TAILQ_INSERT_HEAD(&pmc_bufferlist, plb, plb_next); 1109 } 1110 mtx_init(&pmc_bufferlist_mtx, "pmc-buffer-list", "pmc-leaf", 1111 MTX_SPIN); 1112 mtx_init(&pmc_kthread_mtx, "pmc-kthread", "pmc-sleep", MTX_DEF); 1113} 1114 1115/* 1116 * Shutdown logging. 1117 * 1118 * Destroy mutexes and release memory back the to free pool. 1119 */ 1120 1121void 1122pmclog_shutdown() 1123{ 1124 struct pmclog_buffer *plb; 1125 1126 mtx_destroy(&pmc_kthread_mtx); 1127 mtx_destroy(&pmc_bufferlist_mtx); 1128 1129 while ((plb = TAILQ_FIRST(&pmc_bufferlist)) != NULL) { 1130 TAILQ_REMOVE(&pmc_bufferlist, plb, plb_next); 1131 free(plb, M_PMC); 1132 } 1133} 1134