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 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include <sys/param.h> 37 #include <sys/pmc.h> 38 #include <sys/pmclog.h> 39 40 #include <assert.h> 41 #include <errno.h> 42 #include <pmc.h> 43 #include <pmclog.h> 44 #include <stddef.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <strings.h> 48 #include <unistd.h> 49 50 #include <machine/pmc_mdep.h> 51 52 #include "libpmcinternal.h" 53 54 #define PMCLOG_BUFFER_SIZE 4096 55 56 /* 57 * API NOTES 58 * 59 * The pmclog(3) API is oriented towards parsing an event stream in 60 * "realtime", i.e., from an data source that may or may not preserve 61 * record boundaries -- for example when the data source is elsewhere 62 * on a network. The API allows data to be fed into the parser zero 63 * or more bytes at a time. 64 * 65 * The state for a log file parser is maintained in a 'struct 66 * pmclog_parse_state'. Parser invocations are done by calling 67 * 'pmclog_read()'; this function will inform the caller when a 68 * complete event is parsed. 69 * 70 * The parser first assembles a complete log file event in an internal 71 * work area (see "ps_saved" below). Once a complete log file event 72 * is read, the parser then parses it and converts it to an event 73 * descriptor usable by the client. We could possibly avoid this two 74 * step process by directly parsing the input log to set fields in the 75 * event record. However the parser's state machine would get 76 * insanely complicated, and this code is unlikely to be used in 77 * performance critical paths. 78 */ 79 80 enum pmclog_parser_state { 81 PL_STATE_NEW_RECORD, /* in-between records */ 82 PL_STATE_EXPECTING_HEADER, /* header being read */ 83 PL_STATE_PARTIAL_RECORD, /* header present but not the record */ 84 PL_STATE_ERROR /* parsing error encountered */ 85 }; 86 87 struct pmclog_parse_state { 88 enum pmclog_parser_state ps_state; 89 enum pmc_cputype ps_arch; /* log file architecture */ 90 uint32_t ps_version; /* hwpmc version */ 91 int ps_initialized; /* whether initialized */ 92 int ps_count; /* count of records processed */ 93 off_t ps_offset; /* stream byte offset */ 94 union pmclog_entry ps_saved; /* saved partial log entry */ 95 int ps_svcount; /* #bytes saved */ 96 int ps_fd; /* active fd or -1 */ 97 char *ps_buffer; /* scratch buffer if fd != -1 */ 98 char *ps_data; /* current parse pointer */ 99 size_t ps_len; /* length of buffered data */ 100 }; 101 102 #define PMCLOG_HEADER_FROM_SAVED_STATE(PS) \ 103 (* ((uint32_t *) &(PS)->ps_saved)) 104 105 #define PMCLOG_INITIALIZE_READER(LE,A) LE = (uint32_t *) &(A) 106 #define PMCLOG_READ32(LE,V) do { \ 107 (V) = *(LE)++; \ 108 } while (0) 109 #define PMCLOG_READ64(LE,V) do { \ 110 uint64_t _v; \ 111 _v = (uint64_t) *(LE)++; \ 112 _v |= ((uint64_t) *(LE)++) << 32; \ 113 (V) = _v; \ 114 } while (0) 115 116 #define PMCLOG_READSTRING(LE,DST,LEN) strlcpy((DST), (char *) (LE), (LEN)) 117 118 /* 119 * Assemble a log record from '*len' octets starting from address '*data'. 120 * Update 'data' and 'len' to reflect the number of bytes consumed. 121 * 122 * '*data' is potentially an unaligned address and '*len' octets may 123 * not be enough to complete a event record. 124 */ 125 126 static enum pmclog_parser_state 127 pmclog_get_record(struct pmclog_parse_state *ps, char **data, ssize_t *len) 128 { 129 int avail, copylen, recordsize, used; 130 uint32_t h; 131 const int HEADERSIZE = sizeof(uint32_t); 132 char *src, *dst; 133 134 if ((avail = *len) <= 0) 135 return (ps->ps_state = PL_STATE_ERROR); 136 137 src = *data; 138 h = used = 0; 139 140 if (ps->ps_state == PL_STATE_NEW_RECORD) 141 ps->ps_svcount = 0; 142 143 dst = (char *) &ps->ps_saved + ps->ps_svcount; 144 145 switch (ps->ps_state) { 146 case PL_STATE_NEW_RECORD: 147 148 /* 149 * Transitions: 150 * 151 * Case A: avail < headersize 152 * -> 'expecting header' 153 * 154 * Case B: avail >= headersize 155 * B.1: avail < recordsize 156 * -> 'partial record' 157 * B.2: avail >= recordsize 158 * -> 'new record' 159 */ 160 161 copylen = avail < HEADERSIZE ? avail : HEADERSIZE; 162 bcopy(src, dst, copylen); 163 ps->ps_svcount = used = copylen; 164 165 if (copylen < HEADERSIZE) { 166 ps->ps_state = PL_STATE_EXPECTING_HEADER; 167 goto done; 168 } 169 170 src += copylen; 171 dst += copylen; 172 173 h = PMCLOG_HEADER_FROM_SAVED_STATE(ps); 174 recordsize = PMCLOG_HEADER_TO_LENGTH(h); 175 176 if (recordsize <= 0) 177 goto error; 178 179 if (recordsize <= avail) { /* full record available */ 180 bcopy(src, dst, recordsize - copylen); 181 ps->ps_svcount = used = recordsize; 182 goto done; 183 } 184 185 /* header + a partial record is available */ 186 bcopy(src, dst, avail - copylen); 187 ps->ps_svcount = used = avail; 188 ps->ps_state = PL_STATE_PARTIAL_RECORD; 189 190 break; 191 192 case PL_STATE_EXPECTING_HEADER: 193 194 /* 195 * Transitions: 196 * 197 * Case C: avail+saved < headersize 198 * -> 'expecting header' 199 * 200 * Case D: avail+saved >= headersize 201 * D.1: avail+saved < recordsize 202 * -> 'partial record' 203 * D.2: avail+saved >= recordsize 204 * -> 'new record' 205 * (see PARTIAL_RECORD handling below) 206 */ 207 208 if (avail + ps->ps_svcount < HEADERSIZE) { 209 bcopy(src, dst, avail); 210 ps->ps_svcount += avail; 211 used = avail; 212 break; 213 } 214 215 used = copylen = HEADERSIZE - ps->ps_svcount; 216 bcopy(src, dst, copylen); 217 src += copylen; 218 dst += copylen; 219 avail -= copylen; 220 ps->ps_svcount += copylen; 221 222 /*FALLTHROUGH*/ 223 224 case PL_STATE_PARTIAL_RECORD: 225 226 /* 227 * Transitions: 228 * 229 * Case E: avail+saved < recordsize 230 * -> 'partial record' 231 * 232 * Case F: avail+saved >= recordsize 233 * -> 'new record' 234 */ 235 236 h = PMCLOG_HEADER_FROM_SAVED_STATE(ps); 237 recordsize = PMCLOG_HEADER_TO_LENGTH(h); 238 239 if (recordsize <= 0) 240 goto error; 241 242 if (avail + ps->ps_svcount < recordsize) { 243 copylen = avail; 244 ps->ps_state = PL_STATE_PARTIAL_RECORD; 245 } else { 246 copylen = recordsize - ps->ps_svcount; 247 ps->ps_state = PL_STATE_NEW_RECORD; 248 } 249 250 bcopy(src, dst, copylen); 251 ps->ps_svcount += copylen; 252 used += copylen; 253 break; 254 255 default: 256 goto error; 257 } 258 259 done: 260 *data += used; 261 *len -= used; 262 return ps->ps_state; 263 264 error: 265 ps->ps_state = PL_STATE_ERROR; 266 return ps->ps_state; 267 } 268 269 /* 270 * Get an event from the stream pointed to by '*data'. '*len' 271 * indicates the number of bytes available to parse. Arguments 272 * '*data' and '*len' are updated to indicate the number of bytes 273 * consumed. 274 */ 275 276 static int 277 pmclog_get_event(void *cookie, char **data, ssize_t *len, 278 struct pmclog_ev *ev) 279 { 280 int evlen, pathlen; 281 uint32_t h, *le, npc; 282 enum pmclog_parser_state e; 283 struct pmclog_parse_state *ps; 284 285 ps = (struct pmclog_parse_state *) cookie; 286 287 assert(ps->ps_state != PL_STATE_ERROR); 288 289 if ((e = pmclog_get_record(ps,data,len)) == PL_STATE_ERROR) { 290 ev->pl_state = PMCLOG_ERROR; 291 return -1; 292 } 293 294 if (e != PL_STATE_NEW_RECORD) { 295 ev->pl_state = PMCLOG_REQUIRE_DATA; 296 return -1; 297 } 298 299 PMCLOG_INITIALIZE_READER(le, ps->ps_saved); 300 301 PMCLOG_READ32(le,h); 302 303 if (!PMCLOG_HEADER_CHECK_MAGIC(h)) { 304 ps->ps_state = PL_STATE_ERROR; 305 ev->pl_state = PMCLOG_ERROR; 306 return -1; 307 } 308 309 /* copy out the time stamp */ 310 PMCLOG_READ32(le,ev->pl_ts.tv_sec); 311 PMCLOG_READ32(le,ev->pl_ts.tv_nsec); 312 313 evlen = PMCLOG_HEADER_TO_LENGTH(h); 314 315 #define PMCLOG_GET_PATHLEN(P,E,TYPE) do { \ 316 (P) = (E) - offsetof(struct TYPE, pl_pathname); \ 317 if ((P) > PATH_MAX || (P) < 0) \ 318 goto error; \ 319 } while (0) 320 321 #define PMCLOG_GET_CALLCHAIN_SIZE(SZ,E) do { \ 322 (SZ) = ((E) - offsetof(struct pmclog_callchain, pl_pc)) \ 323 / sizeof(uintfptr_t); \ 324 } while (0); 325 326 switch (ev->pl_type = PMCLOG_HEADER_TO_TYPE(h)) { 327 case PMCLOG_TYPE_CALLCHAIN: 328 PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_pid); 329 PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_pmcid); 330 PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_cpuflags); 331 PMCLOG_GET_CALLCHAIN_SIZE(ev->pl_u.pl_cc.pl_npc,evlen); 332 for (npc = 0; npc < ev->pl_u.pl_cc.pl_npc; npc++) 333 PMCLOG_READADDR(le,ev->pl_u.pl_cc.pl_pc[npc]); 334 for (;npc < PMC_CALLCHAIN_DEPTH_MAX; npc++) 335 ev->pl_u.pl_cc.pl_pc[npc] = (uintfptr_t) 0; 336 break; 337 case PMCLOG_TYPE_CLOSELOG: 338 case PMCLOG_TYPE_DROPNOTIFY: 339 /* nothing to do */ 340 break; 341 case PMCLOG_TYPE_INITIALIZE: 342 PMCLOG_READ32(le,ev->pl_u.pl_i.pl_version); 343 PMCLOG_READ32(le,ev->pl_u.pl_i.pl_arch); 344 ps->ps_version = ev->pl_u.pl_i.pl_version; 345 ps->ps_arch = ev->pl_u.pl_i.pl_arch; 346 ps->ps_initialized = 1; 347 break; 348 case PMCLOG_TYPE_MAP_IN: 349 PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_map_in); 350 PMCLOG_READ32(le,ev->pl_u.pl_mi.pl_pid); 351 PMCLOG_READADDR(le,ev->pl_u.pl_mi.pl_start); 352 PMCLOG_READSTRING(le, ev->pl_u.pl_mi.pl_pathname, pathlen); 353 break; 354 case PMCLOG_TYPE_MAP_OUT: 355 PMCLOG_READ32(le,ev->pl_u.pl_mo.pl_pid); 356 PMCLOG_READADDR(le,ev->pl_u.pl_mo.pl_start); 357 PMCLOG_READADDR(le,ev->pl_u.pl_mo.pl_end); 358 break; 359 case PMCLOG_TYPE_PCSAMPLE: 360 PMCLOG_READ32(le,ev->pl_u.pl_s.pl_pid); 361 PMCLOG_READADDR(le,ev->pl_u.pl_s.pl_pc); 362 PMCLOG_READ32(le,ev->pl_u.pl_s.pl_pmcid); 363 PMCLOG_READ32(le,ev->pl_u.pl_s.pl_usermode); 364 break; 365 case PMCLOG_TYPE_PMCALLOCATE: 366 PMCLOG_READ32(le,ev->pl_u.pl_a.pl_pmcid); 367 PMCLOG_READ32(le,ev->pl_u.pl_a.pl_event); 368 PMCLOG_READ32(le,ev->pl_u.pl_a.pl_flags); 369 if ((ev->pl_u.pl_a.pl_evname = 370 _pmc_name_of_event(ev->pl_u.pl_a.pl_event, ps->ps_arch)) 371 == NULL) 372 goto error; 373 break; 374 case PMCLOG_TYPE_PMCALLOCATEDYN: 375 PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_pmcid); 376 PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_event); 377 PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_flags); 378 PMCLOG_READSTRING(le,ev->pl_u.pl_ad.pl_evname,PMC_NAME_MAX); 379 break; 380 case PMCLOG_TYPE_PMCATTACH: 381 PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_pmcattach); 382 PMCLOG_READ32(le,ev->pl_u.pl_t.pl_pmcid); 383 PMCLOG_READ32(le,ev->pl_u.pl_t.pl_pid); 384 PMCLOG_READSTRING(le,ev->pl_u.pl_t.pl_pathname,pathlen); 385 break; 386 case PMCLOG_TYPE_PMCDETACH: 387 PMCLOG_READ32(le,ev->pl_u.pl_d.pl_pmcid); 388 PMCLOG_READ32(le,ev->pl_u.pl_d.pl_pid); 389 break; 390 case PMCLOG_TYPE_PROCCSW: 391 PMCLOG_READ32(le,ev->pl_u.pl_c.pl_pmcid); 392 PMCLOG_READ64(le,ev->pl_u.pl_c.pl_value); 393 PMCLOG_READ32(le,ev->pl_u.pl_c.pl_pid); 394 break; 395 case PMCLOG_TYPE_PROCEXEC: 396 PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_procexec); 397 PMCLOG_READ32(le,ev->pl_u.pl_x.pl_pid); 398 PMCLOG_READADDR(le,ev->pl_u.pl_x.pl_entryaddr); 399 PMCLOG_READ32(le,ev->pl_u.pl_x.pl_pmcid); 400 PMCLOG_READSTRING(le,ev->pl_u.pl_x.pl_pathname,pathlen); 401 break; 402 case PMCLOG_TYPE_PROCEXIT: 403 PMCLOG_READ32(le,ev->pl_u.pl_e.pl_pmcid); 404 PMCLOG_READ64(le,ev->pl_u.pl_e.pl_value); 405 PMCLOG_READ32(le,ev->pl_u.pl_e.pl_pid); 406 break; 407 case PMCLOG_TYPE_PROCFORK: 408 PMCLOG_READ32(le,ev->pl_u.pl_f.pl_oldpid); 409 PMCLOG_READ32(le,ev->pl_u.pl_f.pl_newpid); 410 break; 411 case PMCLOG_TYPE_SYSEXIT: 412 PMCLOG_READ32(le,ev->pl_u.pl_se.pl_pid); 413 break; 414 case PMCLOG_TYPE_USERDATA: 415 PMCLOG_READ32(le,ev->pl_u.pl_u.pl_userdata); 416 break; 417 default: /* unknown record type */ 418 ps->ps_state = PL_STATE_ERROR; 419 ev->pl_state = PMCLOG_ERROR; 420 return (-1); 421 } 422 423 ev->pl_offset = (ps->ps_offset += evlen); 424 ev->pl_count = (ps->ps_count += 1); 425 ev->pl_state = PMCLOG_OK; 426 return 0; 427 428 error: 429 ev->pl_state = PMCLOG_ERROR; 430 ps->ps_state = PL_STATE_ERROR; 431 return -1; 432 } 433 434 /* 435 * Extract and return the next event from the byte stream. 436 * 437 * Returns 0 and sets the event's state to PMCLOG_OK in case an event 438 * was successfully parsed. Otherwise this function returns -1 and 439 * sets the event's state to one of PMCLOG_REQUIRE_DATA (if more data 440 * is needed) or PMCLOG_EOF (if an EOF was seen) or PMCLOG_ERROR if 441 * a parse error was encountered. 442 */ 443 444 int 445 pmclog_read(void *cookie, struct pmclog_ev *ev) 446 { 447 int retval; 448 ssize_t nread; 449 struct pmclog_parse_state *ps; 450 451 ps = (struct pmclog_parse_state *) cookie; 452 453 if (ps->ps_state == PL_STATE_ERROR) { 454 ev->pl_state = PMCLOG_ERROR; 455 return -1; 456 } 457 458 /* 459 * If there isn't enough data left for a new event try and get 460 * more data. 461 */ 462 if (ps->ps_len == 0) { 463 ev->pl_state = PMCLOG_REQUIRE_DATA; 464 465 /* 466 * If we have a valid file descriptor to read from, attempt 467 * to read from that. This read may return with an error, 468 * (which may be EAGAIN or other recoverable error), or 469 * can return EOF. 470 */ 471 if (ps->ps_fd != PMCLOG_FD_NONE) { 472 refill: 473 nread = read(ps->ps_fd, ps->ps_buffer, 474 PMCLOG_BUFFER_SIZE); 475 476 if (nread <= 0) { 477 if (nread == 0) 478 ev->pl_state = PMCLOG_EOF; 479 else if (errno != EAGAIN) /* not restartable */ 480 ev->pl_state = PMCLOG_ERROR; 481 return -1; 482 } 483 484 ps->ps_len = nread; 485 ps->ps_data = ps->ps_buffer; 486 } else 487 return -1; 488 } 489 490 assert(ps->ps_len > 0); 491 492 493 /* Retrieve one event from the byte stream. */ 494 retval = pmclog_get_event(ps, &ps->ps_data, &ps->ps_len, ev); 495 496 /* 497 * If we need more data and we have a configured fd, try read 498 * from it. 499 */ 500 if (retval < 0 && ev->pl_state == PMCLOG_REQUIRE_DATA && 501 ps->ps_fd != -1) { 502 assert(ps->ps_len == 0); 503 goto refill; 504 } 505 506 return retval; 507 } 508 509 /* 510 * Feed data to a memory based parser. 511 * 512 * The memory area pointed to by 'data' needs to be valid till the 513 * next error return from pmclog_next_event(). 514 */ 515 516 int 517 pmclog_feed(void *cookie, char *data, int len) 518 { 519 struct pmclog_parse_state *ps; 520 521 ps = (struct pmclog_parse_state *) cookie; 522 523 if (len < 0 || /* invalid length */ 524 ps->ps_buffer || /* called for a file parser */ 525 ps->ps_len != 0) /* unnecessary call */ 526 return -1; 527 528 ps->ps_data = data; 529 ps->ps_len = len; 530 531 return 0; 532 } 533 534 /* 535 * Allocate and initialize parser state. 536 */ 537 538 void * 539 pmclog_open(int fd) 540 { 541 struct pmclog_parse_state *ps; 542 543 if ((ps = (struct pmclog_parse_state *) malloc(sizeof(*ps))) == NULL) 544 return NULL; 545 546 ps->ps_state = PL_STATE_NEW_RECORD; 547 ps->ps_arch = -1; 548 ps->ps_initialized = 0; 549 ps->ps_count = 0; 550 ps->ps_offset = (off_t) 0; 551 bzero(&ps->ps_saved, sizeof(ps->ps_saved)); 552 ps->ps_svcount = 0; 553 ps->ps_fd = fd; 554 ps->ps_data = NULL; 555 ps->ps_buffer = NULL; 556 ps->ps_len = 0; 557 558 /* allocate space for a work area */ 559 if (ps->ps_fd != PMCLOG_FD_NONE) { 560 if ((ps->ps_buffer = malloc(PMCLOG_BUFFER_SIZE)) == NULL) { 561 free(ps); 562 return NULL; 563 } 564 } 565 566 return ps; 567 } 568 569 570 /* 571 * Free up parser state. 572 */ 573 574 void 575 pmclog_close(void *cookie) 576 { 577 struct pmclog_parse_state *ps; 578 579 ps = (struct pmclog_parse_state *) cookie; 580 581 if (ps->ps_buffer) 582 free(ps->ps_buffer); 583 584 free(ps); 585 } 586