1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * trace_output.c 4 * 5 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com> 6 * 7 */ 8 #include <linux/module.h> 9 #include <linux/mutex.h> 10 #include <linux/ftrace.h> 11 #include <linux/sched/clock.h> 12 #include <linux/sched/mm.h> 13 14 #include "trace_output.h" 15 16 /* must be a power of 2 */ 17 #define EVENT_HASHSIZE 128 18 19 DECLARE_RWSEM(trace_event_sem); 20 21 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly; 22 23 static int next_event_type = __TRACE_LAST_TYPE + 1; 24 25 enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter) 26 { 27 struct trace_seq *s = &iter->seq; 28 struct trace_entry *entry = iter->ent; 29 struct bputs_entry *field; 30 31 trace_assign_type(field, entry); 32 33 trace_seq_puts(s, field->str); 34 35 return trace_handle_return(s); 36 } 37 38 enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter) 39 { 40 struct trace_seq *s = &iter->seq; 41 struct trace_entry *entry = iter->ent; 42 struct bprint_entry *field; 43 44 trace_assign_type(field, entry); 45 46 trace_seq_bprintf(s, field->fmt, field->buf); 47 48 return trace_handle_return(s); 49 } 50 51 enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter) 52 { 53 struct trace_seq *s = &iter->seq; 54 struct trace_entry *entry = iter->ent; 55 struct print_entry *field; 56 57 trace_assign_type(field, entry); 58 59 trace_seq_puts(s, field->buf); 60 61 return trace_handle_return(s); 62 } 63 64 const char * 65 trace_print_flags_seq(struct trace_seq *p, const char *delim, 66 unsigned long flags, 67 const struct trace_print_flags *flag_array) 68 { 69 unsigned long mask; 70 const char *str; 71 const char *ret = trace_seq_buffer_ptr(p); 72 int i, first = 1; 73 74 for (i = 0; flag_array[i].name && flags; i++) { 75 76 mask = flag_array[i].mask; 77 if ((flags & mask) != mask) 78 continue; 79 80 str = flag_array[i].name; 81 flags &= ~mask; 82 if (!first && delim) 83 trace_seq_puts(p, delim); 84 else 85 first = 0; 86 trace_seq_puts(p, str); 87 } 88 89 /* check for left over flags */ 90 if (flags) { 91 if (!first && delim) 92 trace_seq_puts(p, delim); 93 trace_seq_printf(p, "0x%lx", flags); 94 } 95 96 trace_seq_putc(p, 0); 97 98 return ret; 99 } 100 EXPORT_SYMBOL(trace_print_flags_seq); 101 102 const char * 103 trace_print_symbols_seq(struct trace_seq *p, unsigned long val, 104 const struct trace_print_flags *symbol_array) 105 { 106 int i; 107 const char *ret = trace_seq_buffer_ptr(p); 108 109 for (i = 0; symbol_array[i].name; i++) { 110 111 if (val != symbol_array[i].mask) 112 continue; 113 114 trace_seq_puts(p, symbol_array[i].name); 115 break; 116 } 117 118 if (ret == (const char *)(trace_seq_buffer_ptr(p))) 119 trace_seq_printf(p, "0x%lx", val); 120 121 trace_seq_putc(p, 0); 122 123 return ret; 124 } 125 EXPORT_SYMBOL(trace_print_symbols_seq); 126 127 #if BITS_PER_LONG == 32 128 const char * 129 trace_print_flags_seq_u64(struct trace_seq *p, const char *delim, 130 unsigned long long flags, 131 const struct trace_print_flags_u64 *flag_array) 132 { 133 unsigned long long mask; 134 const char *str; 135 const char *ret = trace_seq_buffer_ptr(p); 136 int i, first = 1; 137 138 for (i = 0; flag_array[i].name && flags; i++) { 139 140 mask = flag_array[i].mask; 141 if ((flags & mask) != mask) 142 continue; 143 144 str = flag_array[i].name; 145 flags &= ~mask; 146 if (!first && delim) 147 trace_seq_puts(p, delim); 148 else 149 first = 0; 150 trace_seq_puts(p, str); 151 } 152 153 /* check for left over flags */ 154 if (flags) { 155 if (!first && delim) 156 trace_seq_puts(p, delim); 157 trace_seq_printf(p, "0x%llx", flags); 158 } 159 160 trace_seq_putc(p, 0); 161 162 return ret; 163 } 164 EXPORT_SYMBOL(trace_print_flags_seq_u64); 165 166 const char * 167 trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, 168 const struct trace_print_flags_u64 *symbol_array) 169 { 170 int i; 171 const char *ret = trace_seq_buffer_ptr(p); 172 173 for (i = 0; symbol_array[i].name; i++) { 174 175 if (val != symbol_array[i].mask) 176 continue; 177 178 trace_seq_puts(p, symbol_array[i].name); 179 break; 180 } 181 182 if (ret == (const char *)(trace_seq_buffer_ptr(p))) 183 trace_seq_printf(p, "0x%llx", val); 184 185 trace_seq_putc(p, 0); 186 187 return ret; 188 } 189 EXPORT_SYMBOL(trace_print_symbols_seq_u64); 190 #endif 191 192 const char * 193 trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr, 194 unsigned int bitmask_size) 195 { 196 const char *ret = trace_seq_buffer_ptr(p); 197 198 trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8); 199 trace_seq_putc(p, 0); 200 201 return ret; 202 } 203 EXPORT_SYMBOL_GPL(trace_print_bitmask_seq); 204 205 /** 206 * trace_print_hex_seq - print buffer as hex sequence 207 * @p: trace seq struct to write to 208 * @buf: The buffer to print 209 * @buf_len: Length of @buf in bytes 210 * @concatenate: Print @buf as single hex string or with spacing 211 * 212 * Prints the passed buffer as a hex sequence either as a whole, 213 * single hex string if @concatenate is true or with spacing after 214 * each byte in case @concatenate is false. 215 */ 216 const char * 217 trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len, 218 bool concatenate) 219 { 220 int i; 221 const char *ret = trace_seq_buffer_ptr(p); 222 223 for (i = 0; i < buf_len; i++) 224 trace_seq_printf(p, "%s%2.2x", concatenate || i == 0 ? "" : " ", 225 buf[i]); 226 trace_seq_putc(p, 0); 227 228 return ret; 229 } 230 EXPORT_SYMBOL(trace_print_hex_seq); 231 232 const char * 233 trace_print_array_seq(struct trace_seq *p, const void *buf, int count, 234 size_t el_size) 235 { 236 const char *ret = trace_seq_buffer_ptr(p); 237 const char *prefix = ""; 238 void *ptr = (void *)buf; 239 size_t buf_len = count * el_size; 240 241 trace_seq_putc(p, '{'); 242 243 while (ptr < buf + buf_len) { 244 switch (el_size) { 245 case 1: 246 trace_seq_printf(p, "%s0x%x", prefix, 247 *(u8 *)ptr); 248 break; 249 case 2: 250 trace_seq_printf(p, "%s0x%x", prefix, 251 *(u16 *)ptr); 252 break; 253 case 4: 254 trace_seq_printf(p, "%s0x%x", prefix, 255 *(u32 *)ptr); 256 break; 257 case 8: 258 trace_seq_printf(p, "%s0x%llx", prefix, 259 *(u64 *)ptr); 260 break; 261 default: 262 trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size, 263 *(u8 *)ptr); 264 el_size = 1; 265 } 266 prefix = ","; 267 ptr += el_size; 268 } 269 270 trace_seq_putc(p, '}'); 271 trace_seq_putc(p, 0); 272 273 return ret; 274 } 275 EXPORT_SYMBOL(trace_print_array_seq); 276 277 int trace_raw_output_prep(struct trace_iterator *iter, 278 struct trace_event *trace_event) 279 { 280 struct trace_event_call *event; 281 struct trace_seq *s = &iter->seq; 282 struct trace_seq *p = &iter->tmp_seq; 283 struct trace_entry *entry; 284 285 event = container_of(trace_event, struct trace_event_call, event); 286 entry = iter->ent; 287 288 if (entry->type != event->event.type) { 289 WARN_ON_ONCE(1); 290 return TRACE_TYPE_UNHANDLED; 291 } 292 293 trace_seq_init(p); 294 trace_seq_printf(s, "%s: ", trace_event_name(event)); 295 296 return trace_handle_return(s); 297 } 298 EXPORT_SYMBOL(trace_raw_output_prep); 299 300 static int trace_output_raw(struct trace_iterator *iter, char *name, 301 char *fmt, va_list ap) 302 { 303 struct trace_seq *s = &iter->seq; 304 305 trace_seq_printf(s, "%s: ", name); 306 trace_seq_vprintf(s, fmt, ap); 307 308 return trace_handle_return(s); 309 } 310 311 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...) 312 { 313 va_list ap; 314 int ret; 315 316 va_start(ap, fmt); 317 ret = trace_output_raw(iter, name, fmt, ap); 318 va_end(ap); 319 320 return ret; 321 } 322 EXPORT_SYMBOL_GPL(trace_output_call); 323 324 #ifdef CONFIG_KRETPROBES 325 static inline const char *kretprobed(const char *name) 326 { 327 static const char tramp_name[] = "kretprobe_trampoline"; 328 int size = sizeof(tramp_name); 329 330 if (strncmp(tramp_name, name, size) == 0) 331 return "[unknown/kretprobe'd]"; 332 return name; 333 } 334 #else 335 static inline const char *kretprobed(const char *name) 336 { 337 return name; 338 } 339 #endif /* CONFIG_KRETPROBES */ 340 341 static void 342 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) 343 { 344 char str[KSYM_SYMBOL_LEN]; 345 #ifdef CONFIG_KALLSYMS 346 const char *name; 347 348 kallsyms_lookup(address, NULL, NULL, NULL, str); 349 350 name = kretprobed(str); 351 352 if (name && strlen(name)) { 353 trace_seq_printf(s, fmt, name); 354 return; 355 } 356 #endif 357 snprintf(str, KSYM_SYMBOL_LEN, "0x%08lx", address); 358 trace_seq_printf(s, fmt, str); 359 } 360 361 static void 362 seq_print_sym_offset(struct trace_seq *s, const char *fmt, 363 unsigned long address) 364 { 365 char str[KSYM_SYMBOL_LEN]; 366 #ifdef CONFIG_KALLSYMS 367 const char *name; 368 369 sprint_symbol(str, address); 370 name = kretprobed(str); 371 372 if (name && strlen(name)) { 373 trace_seq_printf(s, fmt, name); 374 return; 375 } 376 #endif 377 snprintf(str, KSYM_SYMBOL_LEN, "0x%08lx", address); 378 trace_seq_printf(s, fmt, str); 379 } 380 381 #ifndef CONFIG_64BIT 382 # define IP_FMT "%08lx" 383 #else 384 # define IP_FMT "%016lx" 385 #endif 386 387 static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, 388 unsigned long ip, unsigned long sym_flags) 389 { 390 struct file *file = NULL; 391 unsigned long vmstart = 0; 392 int ret = 1; 393 394 if (s->full) 395 return 0; 396 397 if (mm) { 398 const struct vm_area_struct *vma; 399 400 down_read(&mm->mmap_sem); 401 vma = find_vma(mm, ip); 402 if (vma) { 403 file = vma->vm_file; 404 vmstart = vma->vm_start; 405 } 406 if (file) { 407 ret = trace_seq_path(s, &file->f_path); 408 if (ret) 409 trace_seq_printf(s, "[+0x%lx]", 410 ip - vmstart); 411 } 412 up_read(&mm->mmap_sem); 413 } 414 if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file)) 415 trace_seq_printf(s, " <" IP_FMT ">", ip); 416 return !trace_seq_has_overflowed(s); 417 } 418 419 int 420 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) 421 { 422 if (!ip) { 423 trace_seq_putc(s, '0'); 424 goto out; 425 } 426 427 if (sym_flags & TRACE_ITER_SYM_OFFSET) 428 seq_print_sym_offset(s, "%s", ip); 429 else 430 seq_print_sym_short(s, "%s", ip); 431 432 if (sym_flags & TRACE_ITER_SYM_ADDR) 433 trace_seq_printf(s, " <" IP_FMT ">", ip); 434 435 out: 436 return !trace_seq_has_overflowed(s); 437 } 438 439 /** 440 * trace_print_lat_fmt - print the irq, preempt and lockdep fields 441 * @s: trace seq struct to write to 442 * @entry: The trace entry field from the ring buffer 443 * 444 * Prints the generic fields of irqs off, in hard or softirq, preempt 445 * count. 446 */ 447 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry) 448 { 449 char hardsoft_irq; 450 char need_resched; 451 char irqs_off; 452 int hardirq; 453 int softirq; 454 int nmi; 455 456 nmi = entry->flags & TRACE_FLAG_NMI; 457 hardirq = entry->flags & TRACE_FLAG_HARDIRQ; 458 softirq = entry->flags & TRACE_FLAG_SOFTIRQ; 459 460 irqs_off = 461 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : 462 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' : 463 '.'; 464 465 switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | 466 TRACE_FLAG_PREEMPT_RESCHED)) { 467 case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED: 468 need_resched = 'N'; 469 break; 470 case TRACE_FLAG_NEED_RESCHED: 471 need_resched = 'n'; 472 break; 473 case TRACE_FLAG_PREEMPT_RESCHED: 474 need_resched = 'p'; 475 break; 476 default: 477 need_resched = '.'; 478 break; 479 } 480 481 hardsoft_irq = 482 (nmi && hardirq) ? 'Z' : 483 nmi ? 'z' : 484 (hardirq && softirq) ? 'H' : 485 hardirq ? 'h' : 486 softirq ? 's' : 487 '.' ; 488 489 trace_seq_printf(s, "%c%c%c", 490 irqs_off, need_resched, hardsoft_irq); 491 492 if (entry->preempt_count) 493 trace_seq_printf(s, "%x", entry->preempt_count); 494 else 495 trace_seq_putc(s, '.'); 496 497 return !trace_seq_has_overflowed(s); 498 } 499 500 static int 501 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) 502 { 503 char comm[TASK_COMM_LEN]; 504 505 trace_find_cmdline(entry->pid, comm); 506 507 trace_seq_printf(s, "%8.8s-%-5d %3d", 508 comm, entry->pid, cpu); 509 510 return trace_print_lat_fmt(s, entry); 511 } 512 513 #undef MARK 514 #define MARK(v, s) {.val = v, .sym = s} 515 /* trace overhead mark */ 516 static const struct trace_mark { 517 unsigned long long val; /* unit: nsec */ 518 char sym; 519 } mark[] = { 520 MARK(1000000000ULL , '$'), /* 1 sec */ 521 MARK(100000000ULL , '@'), /* 100 msec */ 522 MARK(10000000ULL , '*'), /* 10 msec */ 523 MARK(1000000ULL , '#'), /* 1000 usecs */ 524 MARK(100000ULL , '!'), /* 100 usecs */ 525 MARK(10000ULL , '+'), /* 10 usecs */ 526 }; 527 #undef MARK 528 529 char trace_find_mark(unsigned long long d) 530 { 531 int i; 532 int size = ARRAY_SIZE(mark); 533 534 for (i = 0; i < size; i++) { 535 if (d > mark[i].val) 536 break; 537 } 538 539 return (i == size) ? ' ' : mark[i].sym; 540 } 541 542 static int 543 lat_print_timestamp(struct trace_iterator *iter, u64 next_ts) 544 { 545 struct trace_array *tr = iter->tr; 546 unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE; 547 unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS; 548 unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start; 549 unsigned long long rel_ts = next_ts - iter->ts; 550 struct trace_seq *s = &iter->seq; 551 552 if (in_ns) { 553 abs_ts = ns2usecs(abs_ts); 554 rel_ts = ns2usecs(rel_ts); 555 } 556 557 if (verbose && in_ns) { 558 unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC); 559 unsigned long abs_msec = (unsigned long)abs_ts; 560 unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC); 561 unsigned long rel_msec = (unsigned long)rel_ts; 562 563 trace_seq_printf( 564 s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ", 565 ns2usecs(iter->ts), 566 abs_msec, abs_usec, 567 rel_msec, rel_usec); 568 569 } else if (verbose && !in_ns) { 570 trace_seq_printf( 571 s, "[%016llx] %lld (+%lld): ", 572 iter->ts, abs_ts, rel_ts); 573 574 } else if (!verbose && in_ns) { 575 trace_seq_printf( 576 s, " %4lldus%c: ", 577 abs_ts, 578 trace_find_mark(rel_ts * NSEC_PER_USEC)); 579 580 } else { /* !verbose && !in_ns */ 581 trace_seq_printf(s, " %4lld: ", abs_ts); 582 } 583 584 return !trace_seq_has_overflowed(s); 585 } 586 587 int trace_print_context(struct trace_iterator *iter) 588 { 589 struct trace_array *tr = iter->tr; 590 struct trace_seq *s = &iter->seq; 591 struct trace_entry *entry = iter->ent; 592 unsigned long long t; 593 unsigned long secs, usec_rem; 594 char comm[TASK_COMM_LEN]; 595 596 trace_find_cmdline(entry->pid, comm); 597 598 trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid); 599 600 if (tr->trace_flags & TRACE_ITER_RECORD_TGID) { 601 unsigned int tgid = trace_find_tgid(entry->pid); 602 603 if (!tgid) 604 trace_seq_printf(s, "(-----) "); 605 else 606 trace_seq_printf(s, "(%5d) ", tgid); 607 } 608 609 trace_seq_printf(s, "[%03d] ", iter->cpu); 610 611 if (tr->trace_flags & TRACE_ITER_IRQ_INFO) 612 trace_print_lat_fmt(s, entry); 613 614 if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) { 615 t = ns2usecs(iter->ts); 616 usec_rem = do_div(t, USEC_PER_SEC); 617 secs = (unsigned long)t; 618 trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem); 619 } else 620 trace_seq_printf(s, " %12llu: ", iter->ts); 621 622 return !trace_seq_has_overflowed(s); 623 } 624 625 int trace_print_lat_context(struct trace_iterator *iter) 626 { 627 struct trace_array *tr = iter->tr; 628 /* trace_find_next_entry will reset ent_size */ 629 int ent_size = iter->ent_size; 630 struct trace_seq *s = &iter->seq; 631 u64 next_ts; 632 struct trace_entry *entry = iter->ent, 633 *next_entry = trace_find_next_entry(iter, NULL, 634 &next_ts); 635 unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE); 636 637 /* Restore the original ent_size */ 638 iter->ent_size = ent_size; 639 640 if (!next_entry) 641 next_ts = iter->ts; 642 643 if (verbose) { 644 char comm[TASK_COMM_LEN]; 645 646 trace_find_cmdline(entry->pid, comm); 647 648 trace_seq_printf( 649 s, "%16s %5d %3d %d %08x %08lx ", 650 comm, entry->pid, iter->cpu, entry->flags, 651 entry->preempt_count, iter->idx); 652 } else { 653 lat_print_generic(s, entry, iter->cpu); 654 } 655 656 lat_print_timestamp(iter, next_ts); 657 658 return !trace_seq_has_overflowed(s); 659 } 660 661 /** 662 * ftrace_find_event - find a registered event 663 * @type: the type of event to look for 664 * 665 * Returns an event of type @type otherwise NULL 666 * Called with trace_event_read_lock() held. 667 */ 668 struct trace_event *ftrace_find_event(int type) 669 { 670 struct trace_event *event; 671 unsigned key; 672 673 key = type & (EVENT_HASHSIZE - 1); 674 675 hlist_for_each_entry(event, &event_hash[key], node) { 676 if (event->type == type) 677 return event; 678 } 679 680 return NULL; 681 } 682 683 static LIST_HEAD(ftrace_event_list); 684 685 static int trace_search_list(struct list_head **list) 686 { 687 struct trace_event *e; 688 int last = __TRACE_LAST_TYPE; 689 690 if (list_empty(&ftrace_event_list)) { 691 *list = &ftrace_event_list; 692 return last + 1; 693 } 694 695 /* 696 * We used up all possible max events, 697 * lets see if somebody freed one. 698 */ 699 list_for_each_entry(e, &ftrace_event_list, list) { 700 if (e->type != last + 1) 701 break; 702 last++; 703 } 704 705 /* Did we used up all 65 thousand events??? */ 706 if ((last + 1) > TRACE_EVENT_TYPE_MAX) 707 return 0; 708 709 *list = &e->list; 710 return last + 1; 711 } 712 713 void trace_event_read_lock(void) 714 { 715 down_read(&trace_event_sem); 716 } 717 718 void trace_event_read_unlock(void) 719 { 720 up_read(&trace_event_sem); 721 } 722 723 /** 724 * register_trace_event - register output for an event type 725 * @event: the event type to register 726 * 727 * Event types are stored in a hash and this hash is used to 728 * find a way to print an event. If the @event->type is set 729 * then it will use that type, otherwise it will assign a 730 * type to use. 731 * 732 * If you assign your own type, please make sure it is added 733 * to the trace_type enum in trace.h, to avoid collisions 734 * with the dynamic types. 735 * 736 * Returns the event type number or zero on error. 737 */ 738 int register_trace_event(struct trace_event *event) 739 { 740 unsigned key; 741 int ret = 0; 742 743 down_write(&trace_event_sem); 744 745 if (WARN_ON(!event)) 746 goto out; 747 748 if (WARN_ON(!event->funcs)) 749 goto out; 750 751 INIT_LIST_HEAD(&event->list); 752 753 if (!event->type) { 754 struct list_head *list = NULL; 755 756 if (next_event_type > TRACE_EVENT_TYPE_MAX) { 757 758 event->type = trace_search_list(&list); 759 if (!event->type) 760 goto out; 761 762 } else { 763 764 event->type = next_event_type++; 765 list = &ftrace_event_list; 766 } 767 768 if (WARN_ON(ftrace_find_event(event->type))) 769 goto out; 770 771 list_add_tail(&event->list, list); 772 773 } else if (event->type > __TRACE_LAST_TYPE) { 774 printk(KERN_WARNING "Need to add type to trace.h\n"); 775 WARN_ON(1); 776 goto out; 777 } else { 778 /* Is this event already used */ 779 if (ftrace_find_event(event->type)) 780 goto out; 781 } 782 783 if (event->funcs->trace == NULL) 784 event->funcs->trace = trace_nop_print; 785 if (event->funcs->raw == NULL) 786 event->funcs->raw = trace_nop_print; 787 if (event->funcs->hex == NULL) 788 event->funcs->hex = trace_nop_print; 789 if (event->funcs->binary == NULL) 790 event->funcs->binary = trace_nop_print; 791 792 key = event->type & (EVENT_HASHSIZE - 1); 793 794 hlist_add_head(&event->node, &event_hash[key]); 795 796 ret = event->type; 797 out: 798 up_write(&trace_event_sem); 799 800 return ret; 801 } 802 EXPORT_SYMBOL_GPL(register_trace_event); 803 804 /* 805 * Used by module code with the trace_event_sem held for write. 806 */ 807 int __unregister_trace_event(struct trace_event *event) 808 { 809 hlist_del(&event->node); 810 list_del(&event->list); 811 return 0; 812 } 813 814 /** 815 * unregister_trace_event - remove a no longer used event 816 * @event: the event to remove 817 */ 818 int unregister_trace_event(struct trace_event *event) 819 { 820 down_write(&trace_event_sem); 821 __unregister_trace_event(event); 822 up_write(&trace_event_sem); 823 824 return 0; 825 } 826 EXPORT_SYMBOL_GPL(unregister_trace_event); 827 828 /* 829 * Standard events 830 */ 831 832 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags, 833 struct trace_event *event) 834 { 835 trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type); 836 837 return trace_handle_return(&iter->seq); 838 } 839 840 /* TRACE_FN */ 841 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags, 842 struct trace_event *event) 843 { 844 struct ftrace_entry *field; 845 struct trace_seq *s = &iter->seq; 846 847 trace_assign_type(field, iter->ent); 848 849 seq_print_ip_sym(s, field->ip, flags); 850 851 if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) { 852 trace_seq_puts(s, " <-"); 853 seq_print_ip_sym(s, field->parent_ip, flags); 854 } 855 856 trace_seq_putc(s, '\n'); 857 858 return trace_handle_return(s); 859 } 860 861 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags, 862 struct trace_event *event) 863 { 864 struct ftrace_entry *field; 865 866 trace_assign_type(field, iter->ent); 867 868 trace_seq_printf(&iter->seq, "%lx %lx\n", 869 field->ip, 870 field->parent_ip); 871 872 return trace_handle_return(&iter->seq); 873 } 874 875 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags, 876 struct trace_event *event) 877 { 878 struct ftrace_entry *field; 879 struct trace_seq *s = &iter->seq; 880 881 trace_assign_type(field, iter->ent); 882 883 SEQ_PUT_HEX_FIELD(s, field->ip); 884 SEQ_PUT_HEX_FIELD(s, field->parent_ip); 885 886 return trace_handle_return(s); 887 } 888 889 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags, 890 struct trace_event *event) 891 { 892 struct ftrace_entry *field; 893 struct trace_seq *s = &iter->seq; 894 895 trace_assign_type(field, iter->ent); 896 897 SEQ_PUT_FIELD(s, field->ip); 898 SEQ_PUT_FIELD(s, field->parent_ip); 899 900 return trace_handle_return(s); 901 } 902 903 static struct trace_event_functions trace_fn_funcs = { 904 .trace = trace_fn_trace, 905 .raw = trace_fn_raw, 906 .hex = trace_fn_hex, 907 .binary = trace_fn_bin, 908 }; 909 910 static struct trace_event trace_fn_event = { 911 .type = TRACE_FN, 912 .funcs = &trace_fn_funcs, 913 }; 914 915 /* TRACE_CTX an TRACE_WAKE */ 916 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter, 917 char *delim) 918 { 919 struct ctx_switch_entry *field; 920 char comm[TASK_COMM_LEN]; 921 int S, T; 922 923 924 trace_assign_type(field, iter->ent); 925 926 T = task_index_to_char(field->next_state); 927 S = task_index_to_char(field->prev_state); 928 trace_find_cmdline(field->next_pid, comm); 929 trace_seq_printf(&iter->seq, 930 " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n", 931 field->prev_pid, 932 field->prev_prio, 933 S, delim, 934 field->next_cpu, 935 field->next_pid, 936 field->next_prio, 937 T, comm); 938 939 return trace_handle_return(&iter->seq); 940 } 941 942 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags, 943 struct trace_event *event) 944 { 945 return trace_ctxwake_print(iter, "==>"); 946 } 947 948 static enum print_line_t trace_wake_print(struct trace_iterator *iter, 949 int flags, struct trace_event *event) 950 { 951 return trace_ctxwake_print(iter, " +"); 952 } 953 954 static int trace_ctxwake_raw(struct trace_iterator *iter, char S) 955 { 956 struct ctx_switch_entry *field; 957 int T; 958 959 trace_assign_type(field, iter->ent); 960 961 if (!S) 962 S = task_index_to_char(field->prev_state); 963 T = task_index_to_char(field->next_state); 964 trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n", 965 field->prev_pid, 966 field->prev_prio, 967 S, 968 field->next_cpu, 969 field->next_pid, 970 field->next_prio, 971 T); 972 973 return trace_handle_return(&iter->seq); 974 } 975 976 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags, 977 struct trace_event *event) 978 { 979 return trace_ctxwake_raw(iter, 0); 980 } 981 982 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags, 983 struct trace_event *event) 984 { 985 return trace_ctxwake_raw(iter, '+'); 986 } 987 988 989 static int trace_ctxwake_hex(struct trace_iterator *iter, char S) 990 { 991 struct ctx_switch_entry *field; 992 struct trace_seq *s = &iter->seq; 993 int T; 994 995 trace_assign_type(field, iter->ent); 996 997 if (!S) 998 S = task_index_to_char(field->prev_state); 999 T = task_index_to_char(field->next_state); 1000 1001 SEQ_PUT_HEX_FIELD(s, field->prev_pid); 1002 SEQ_PUT_HEX_FIELD(s, field->prev_prio); 1003 SEQ_PUT_HEX_FIELD(s, S); 1004 SEQ_PUT_HEX_FIELD(s, field->next_cpu); 1005 SEQ_PUT_HEX_FIELD(s, field->next_pid); 1006 SEQ_PUT_HEX_FIELD(s, field->next_prio); 1007 SEQ_PUT_HEX_FIELD(s, T); 1008 1009 return trace_handle_return(s); 1010 } 1011 1012 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags, 1013 struct trace_event *event) 1014 { 1015 return trace_ctxwake_hex(iter, 0); 1016 } 1017 1018 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags, 1019 struct trace_event *event) 1020 { 1021 return trace_ctxwake_hex(iter, '+'); 1022 } 1023 1024 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter, 1025 int flags, struct trace_event *event) 1026 { 1027 struct ctx_switch_entry *field; 1028 struct trace_seq *s = &iter->seq; 1029 1030 trace_assign_type(field, iter->ent); 1031 1032 SEQ_PUT_FIELD(s, field->prev_pid); 1033 SEQ_PUT_FIELD(s, field->prev_prio); 1034 SEQ_PUT_FIELD(s, field->prev_state); 1035 SEQ_PUT_FIELD(s, field->next_cpu); 1036 SEQ_PUT_FIELD(s, field->next_pid); 1037 SEQ_PUT_FIELD(s, field->next_prio); 1038 SEQ_PUT_FIELD(s, field->next_state); 1039 1040 return trace_handle_return(s); 1041 } 1042 1043 static struct trace_event_functions trace_ctx_funcs = { 1044 .trace = trace_ctx_print, 1045 .raw = trace_ctx_raw, 1046 .hex = trace_ctx_hex, 1047 .binary = trace_ctxwake_bin, 1048 }; 1049 1050 static struct trace_event trace_ctx_event = { 1051 .type = TRACE_CTX, 1052 .funcs = &trace_ctx_funcs, 1053 }; 1054 1055 static struct trace_event_functions trace_wake_funcs = { 1056 .trace = trace_wake_print, 1057 .raw = trace_wake_raw, 1058 .hex = trace_wake_hex, 1059 .binary = trace_ctxwake_bin, 1060 }; 1061 1062 static struct trace_event trace_wake_event = { 1063 .type = TRACE_WAKE, 1064 .funcs = &trace_wake_funcs, 1065 }; 1066 1067 /* TRACE_STACK */ 1068 1069 static enum print_line_t trace_stack_print(struct trace_iterator *iter, 1070 int flags, struct trace_event *event) 1071 { 1072 struct stack_entry *field; 1073 struct trace_seq *s = &iter->seq; 1074 unsigned long *p; 1075 unsigned long *end; 1076 1077 trace_assign_type(field, iter->ent); 1078 end = (unsigned long *)((long)iter->ent + iter->ent_size); 1079 1080 trace_seq_puts(s, "<stack trace>\n"); 1081 1082 for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) { 1083 1084 if (trace_seq_has_overflowed(s)) 1085 break; 1086 1087 trace_seq_puts(s, " => "); 1088 seq_print_ip_sym(s, *p, flags); 1089 trace_seq_putc(s, '\n'); 1090 } 1091 1092 return trace_handle_return(s); 1093 } 1094 1095 static struct trace_event_functions trace_stack_funcs = { 1096 .trace = trace_stack_print, 1097 }; 1098 1099 static struct trace_event trace_stack_event = { 1100 .type = TRACE_STACK, 1101 .funcs = &trace_stack_funcs, 1102 }; 1103 1104 /* TRACE_USER_STACK */ 1105 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter, 1106 int flags, struct trace_event *event) 1107 { 1108 struct trace_array *tr = iter->tr; 1109 struct userstack_entry *field; 1110 struct trace_seq *s = &iter->seq; 1111 struct mm_struct *mm = NULL; 1112 unsigned int i; 1113 1114 trace_assign_type(field, iter->ent); 1115 1116 trace_seq_puts(s, "<user stack trace>\n"); 1117 1118 if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) { 1119 struct task_struct *task; 1120 /* 1121 * we do the lookup on the thread group leader, 1122 * since individual threads might have already quit! 1123 */ 1124 rcu_read_lock(); 1125 task = find_task_by_vpid(field->tgid); 1126 if (task) 1127 mm = get_task_mm(task); 1128 rcu_read_unlock(); 1129 } 1130 1131 for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { 1132 unsigned long ip = field->caller[i]; 1133 1134 if (ip == ULONG_MAX || trace_seq_has_overflowed(s)) 1135 break; 1136 1137 trace_seq_puts(s, " => "); 1138 1139 if (!ip) { 1140 trace_seq_puts(s, "??"); 1141 trace_seq_putc(s, '\n'); 1142 continue; 1143 } 1144 1145 seq_print_user_ip(s, mm, ip, flags); 1146 trace_seq_putc(s, '\n'); 1147 } 1148 1149 if (mm) 1150 mmput(mm); 1151 1152 return trace_handle_return(s); 1153 } 1154 1155 static struct trace_event_functions trace_user_stack_funcs = { 1156 .trace = trace_user_stack_print, 1157 }; 1158 1159 static struct trace_event trace_user_stack_event = { 1160 .type = TRACE_USER_STACK, 1161 .funcs = &trace_user_stack_funcs, 1162 }; 1163 1164 /* TRACE_HWLAT */ 1165 static enum print_line_t 1166 trace_hwlat_print(struct trace_iterator *iter, int flags, 1167 struct trace_event *event) 1168 { 1169 struct trace_entry *entry = iter->ent; 1170 struct trace_seq *s = &iter->seq; 1171 struct hwlat_entry *field; 1172 1173 trace_assign_type(field, entry); 1174 1175 trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%lld.%09ld", 1176 field->seqnum, 1177 field->duration, 1178 field->outer_duration, 1179 (long long)field->timestamp.tv_sec, 1180 field->timestamp.tv_nsec); 1181 1182 if (field->nmi_count) { 1183 /* 1184 * The generic sched_clock() is not NMI safe, thus 1185 * we only record the count and not the time. 1186 */ 1187 if (!IS_ENABLED(CONFIG_GENERIC_SCHED_CLOCK)) 1188 trace_seq_printf(s, " nmi-total:%llu", 1189 field->nmi_total_ts); 1190 trace_seq_printf(s, " nmi-count:%u", 1191 field->nmi_count); 1192 } 1193 1194 trace_seq_putc(s, '\n'); 1195 1196 return trace_handle_return(s); 1197 } 1198 1199 1200 static enum print_line_t 1201 trace_hwlat_raw(struct trace_iterator *iter, int flags, 1202 struct trace_event *event) 1203 { 1204 struct hwlat_entry *field; 1205 struct trace_seq *s = &iter->seq; 1206 1207 trace_assign_type(field, iter->ent); 1208 1209 trace_seq_printf(s, "%llu %lld %lld %09ld %u\n", 1210 field->duration, 1211 field->outer_duration, 1212 (long long)field->timestamp.tv_sec, 1213 field->timestamp.tv_nsec, 1214 field->seqnum); 1215 1216 return trace_handle_return(s); 1217 } 1218 1219 static struct trace_event_functions trace_hwlat_funcs = { 1220 .trace = trace_hwlat_print, 1221 .raw = trace_hwlat_raw, 1222 }; 1223 1224 static struct trace_event trace_hwlat_event = { 1225 .type = TRACE_HWLAT, 1226 .funcs = &trace_hwlat_funcs, 1227 }; 1228 1229 /* TRACE_BPUTS */ 1230 static enum print_line_t 1231 trace_bputs_print(struct trace_iterator *iter, int flags, 1232 struct trace_event *event) 1233 { 1234 struct trace_entry *entry = iter->ent; 1235 struct trace_seq *s = &iter->seq; 1236 struct bputs_entry *field; 1237 1238 trace_assign_type(field, entry); 1239 1240 seq_print_ip_sym(s, field->ip, flags); 1241 trace_seq_puts(s, ": "); 1242 trace_seq_puts(s, field->str); 1243 1244 return trace_handle_return(s); 1245 } 1246 1247 1248 static enum print_line_t 1249 trace_bputs_raw(struct trace_iterator *iter, int flags, 1250 struct trace_event *event) 1251 { 1252 struct bputs_entry *field; 1253 struct trace_seq *s = &iter->seq; 1254 1255 trace_assign_type(field, iter->ent); 1256 1257 trace_seq_printf(s, ": %lx : ", field->ip); 1258 trace_seq_puts(s, field->str); 1259 1260 return trace_handle_return(s); 1261 } 1262 1263 static struct trace_event_functions trace_bputs_funcs = { 1264 .trace = trace_bputs_print, 1265 .raw = trace_bputs_raw, 1266 }; 1267 1268 static struct trace_event trace_bputs_event = { 1269 .type = TRACE_BPUTS, 1270 .funcs = &trace_bputs_funcs, 1271 }; 1272 1273 /* TRACE_BPRINT */ 1274 static enum print_line_t 1275 trace_bprint_print(struct trace_iterator *iter, int flags, 1276 struct trace_event *event) 1277 { 1278 struct trace_entry *entry = iter->ent; 1279 struct trace_seq *s = &iter->seq; 1280 struct bprint_entry *field; 1281 1282 trace_assign_type(field, entry); 1283 1284 seq_print_ip_sym(s, field->ip, flags); 1285 trace_seq_puts(s, ": "); 1286 trace_seq_bprintf(s, field->fmt, field->buf); 1287 1288 return trace_handle_return(s); 1289 } 1290 1291 1292 static enum print_line_t 1293 trace_bprint_raw(struct trace_iterator *iter, int flags, 1294 struct trace_event *event) 1295 { 1296 struct bprint_entry *field; 1297 struct trace_seq *s = &iter->seq; 1298 1299 trace_assign_type(field, iter->ent); 1300 1301 trace_seq_printf(s, ": %lx : ", field->ip); 1302 trace_seq_bprintf(s, field->fmt, field->buf); 1303 1304 return trace_handle_return(s); 1305 } 1306 1307 static struct trace_event_functions trace_bprint_funcs = { 1308 .trace = trace_bprint_print, 1309 .raw = trace_bprint_raw, 1310 }; 1311 1312 static struct trace_event trace_bprint_event = { 1313 .type = TRACE_BPRINT, 1314 .funcs = &trace_bprint_funcs, 1315 }; 1316 1317 /* TRACE_PRINT */ 1318 static enum print_line_t trace_print_print(struct trace_iterator *iter, 1319 int flags, struct trace_event *event) 1320 { 1321 struct print_entry *field; 1322 struct trace_seq *s = &iter->seq; 1323 1324 trace_assign_type(field, iter->ent); 1325 1326 seq_print_ip_sym(s, field->ip, flags); 1327 trace_seq_printf(s, ": %s", field->buf); 1328 1329 return trace_handle_return(s); 1330 } 1331 1332 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags, 1333 struct trace_event *event) 1334 { 1335 struct print_entry *field; 1336 1337 trace_assign_type(field, iter->ent); 1338 1339 trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf); 1340 1341 return trace_handle_return(&iter->seq); 1342 } 1343 1344 static struct trace_event_functions trace_print_funcs = { 1345 .trace = trace_print_print, 1346 .raw = trace_print_raw, 1347 }; 1348 1349 static struct trace_event trace_print_event = { 1350 .type = TRACE_PRINT, 1351 .funcs = &trace_print_funcs, 1352 }; 1353 1354 static enum print_line_t trace_raw_data(struct trace_iterator *iter, int flags, 1355 struct trace_event *event) 1356 { 1357 struct raw_data_entry *field; 1358 int i; 1359 1360 trace_assign_type(field, iter->ent); 1361 1362 trace_seq_printf(&iter->seq, "# %x buf:", field->id); 1363 1364 for (i = 0; i < iter->ent_size - offsetof(struct raw_data_entry, buf); i++) 1365 trace_seq_printf(&iter->seq, " %02x", 1366 (unsigned char)field->buf[i]); 1367 1368 trace_seq_putc(&iter->seq, '\n'); 1369 1370 return trace_handle_return(&iter->seq); 1371 } 1372 1373 static struct trace_event_functions trace_raw_data_funcs = { 1374 .trace = trace_raw_data, 1375 .raw = trace_raw_data, 1376 }; 1377 1378 static struct trace_event trace_raw_data_event = { 1379 .type = TRACE_RAW_DATA, 1380 .funcs = &trace_raw_data_funcs, 1381 }; 1382 1383 1384 static struct trace_event *events[] __initdata = { 1385 &trace_fn_event, 1386 &trace_ctx_event, 1387 &trace_wake_event, 1388 &trace_stack_event, 1389 &trace_user_stack_event, 1390 &trace_bputs_event, 1391 &trace_bprint_event, 1392 &trace_print_event, 1393 &trace_hwlat_event, 1394 &trace_raw_data_event, 1395 NULL 1396 }; 1397 1398 __init static int init_events(void) 1399 { 1400 struct trace_event *event; 1401 int i, ret; 1402 1403 for (i = 0; events[i]; i++) { 1404 event = events[i]; 1405 1406 ret = register_trace_event(event); 1407 if (!ret) { 1408 printk(KERN_WARNING "event %d failed to register\n", 1409 event->type); 1410 WARN_ON_ONCE(1); 1411 } 1412 } 1413 1414 return 0; 1415 } 1416 early_initcall(init_events); 1417