1 /* 2 * trace_output.c 3 * 4 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com> 5 * 6 */ 7 8 #include <linux/module.h> 9 #include <linux/mutex.h> 10 #include <linux/ftrace.h> 11 12 #include "trace_output.h" 13 14 /* must be a power of 2 */ 15 #define EVENT_HASHSIZE 128 16 17 DECLARE_RWSEM(trace_event_mutex); 18 19 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly; 20 21 static int next_event_type = __TRACE_LAST_TYPE + 1; 22 23 int trace_print_seq(struct seq_file *m, struct trace_seq *s) 24 { 25 int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; 26 int ret; 27 28 ret = seq_write(m, s->buffer, len); 29 30 /* 31 * Only reset this buffer if we successfully wrote to the 32 * seq_file buffer. 33 */ 34 if (!ret) 35 trace_seq_init(s); 36 37 return ret; 38 } 39 40 enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter) 41 { 42 struct trace_seq *s = &iter->seq; 43 struct trace_entry *entry = iter->ent; 44 struct bprint_entry *field; 45 int ret; 46 47 trace_assign_type(field, entry); 48 49 ret = trace_seq_bprintf(s, field->fmt, field->buf); 50 if (!ret) 51 return TRACE_TYPE_PARTIAL_LINE; 52 53 return TRACE_TYPE_HANDLED; 54 } 55 56 enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter) 57 { 58 struct trace_seq *s = &iter->seq; 59 struct trace_entry *entry = iter->ent; 60 struct print_entry *field; 61 int ret; 62 63 trace_assign_type(field, entry); 64 65 ret = trace_seq_printf(s, "%s", field->buf); 66 if (!ret) 67 return TRACE_TYPE_PARTIAL_LINE; 68 69 return TRACE_TYPE_HANDLED; 70 } 71 72 /** 73 * trace_seq_printf - sequence printing of trace information 74 * @s: trace sequence descriptor 75 * @fmt: printf format string 76 * 77 * It returns 0 if the trace oversizes the buffer's free 78 * space, 1 otherwise. 79 * 80 * The tracer may use either sequence operations or its own 81 * copy to user routines. To simplify formating of a trace 82 * trace_seq_printf is used to store strings into a special 83 * buffer (@s). Then the output may be either used by 84 * the sequencer or pulled into another buffer. 85 */ 86 int 87 trace_seq_printf(struct trace_seq *s, const char *fmt, ...) 88 { 89 int len = (PAGE_SIZE - 1) - s->len; 90 va_list ap; 91 int ret; 92 93 if (s->full || !len) 94 return 0; 95 96 va_start(ap, fmt); 97 ret = vsnprintf(s->buffer + s->len, len, fmt, ap); 98 va_end(ap); 99 100 /* If we can't write it all, don't bother writing anything */ 101 if (ret >= len) { 102 s->full = 1; 103 return 0; 104 } 105 106 s->len += ret; 107 108 return 1; 109 } 110 EXPORT_SYMBOL_GPL(trace_seq_printf); 111 112 /** 113 * trace_seq_vprintf - sequence printing of trace information 114 * @s: trace sequence descriptor 115 * @fmt: printf format string 116 * 117 * The tracer may use either sequence operations or its own 118 * copy to user routines. To simplify formating of a trace 119 * trace_seq_printf is used to store strings into a special 120 * buffer (@s). Then the output may be either used by 121 * the sequencer or pulled into another buffer. 122 */ 123 int 124 trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args) 125 { 126 int len = (PAGE_SIZE - 1) - s->len; 127 int ret; 128 129 if (s->full || !len) 130 return 0; 131 132 ret = vsnprintf(s->buffer + s->len, len, fmt, args); 133 134 /* If we can't write it all, don't bother writing anything */ 135 if (ret >= len) { 136 s->full = 1; 137 return 0; 138 } 139 140 s->len += ret; 141 142 return len; 143 } 144 EXPORT_SYMBOL_GPL(trace_seq_vprintf); 145 146 int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary) 147 { 148 int len = (PAGE_SIZE - 1) - s->len; 149 int ret; 150 151 if (s->full || !len) 152 return 0; 153 154 ret = bstr_printf(s->buffer + s->len, len, fmt, binary); 155 156 /* If we can't write it all, don't bother writing anything */ 157 if (ret >= len) { 158 s->full = 1; 159 return 0; 160 } 161 162 s->len += ret; 163 164 return len; 165 } 166 167 /** 168 * trace_seq_puts - trace sequence printing of simple string 169 * @s: trace sequence descriptor 170 * @str: simple string to record 171 * 172 * The tracer may use either the sequence operations or its own 173 * copy to user routines. This function records a simple string 174 * into a special buffer (@s) for later retrieval by a sequencer 175 * or other mechanism. 176 */ 177 int trace_seq_puts(struct trace_seq *s, const char *str) 178 { 179 int len = strlen(str); 180 181 if (s->full) 182 return 0; 183 184 if (len > ((PAGE_SIZE - 1) - s->len)) { 185 s->full = 1; 186 return 0; 187 } 188 189 memcpy(s->buffer + s->len, str, len); 190 s->len += len; 191 192 return len; 193 } 194 195 int trace_seq_putc(struct trace_seq *s, unsigned char c) 196 { 197 if (s->full) 198 return 0; 199 200 if (s->len >= (PAGE_SIZE - 1)) { 201 s->full = 1; 202 return 0; 203 } 204 205 s->buffer[s->len++] = c; 206 207 return 1; 208 } 209 EXPORT_SYMBOL(trace_seq_putc); 210 211 int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len) 212 { 213 if (s->full) 214 return 0; 215 216 if (len > ((PAGE_SIZE - 1) - s->len)) { 217 s->full = 1; 218 return 0; 219 } 220 221 memcpy(s->buffer + s->len, mem, len); 222 s->len += len; 223 224 return len; 225 } 226 227 int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len) 228 { 229 unsigned char hex[HEX_CHARS]; 230 const unsigned char *data = mem; 231 int i, j; 232 233 if (s->full) 234 return 0; 235 236 #ifdef __BIG_ENDIAN 237 for (i = 0, j = 0; i < len; i++) { 238 #else 239 for (i = len-1, j = 0; i >= 0; i--) { 240 #endif 241 hex[j++] = hex_asc_hi(data[i]); 242 hex[j++] = hex_asc_lo(data[i]); 243 } 244 hex[j++] = ' '; 245 246 return trace_seq_putmem(s, hex, j); 247 } 248 249 void *trace_seq_reserve(struct trace_seq *s, size_t len) 250 { 251 void *ret; 252 253 if (s->full) 254 return NULL; 255 256 if (len > ((PAGE_SIZE - 1) - s->len)) { 257 s->full = 1; 258 return NULL; 259 } 260 261 ret = s->buffer + s->len; 262 s->len += len; 263 264 return ret; 265 } 266 267 int trace_seq_path(struct trace_seq *s, const struct path *path) 268 { 269 unsigned char *p; 270 271 if (s->full) 272 return 0; 273 274 if (s->len >= (PAGE_SIZE - 1)) { 275 s->full = 1; 276 return 0; 277 } 278 279 p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len); 280 if (!IS_ERR(p)) { 281 p = mangle_path(s->buffer + s->len, p, "\n"); 282 if (p) { 283 s->len = p - s->buffer; 284 return 1; 285 } 286 } else { 287 s->buffer[s->len++] = '?'; 288 return 1; 289 } 290 291 s->full = 1; 292 return 0; 293 } 294 295 const char * 296 ftrace_print_flags_seq(struct trace_seq *p, const char *delim, 297 unsigned long flags, 298 const struct trace_print_flags *flag_array) 299 { 300 unsigned long mask; 301 const char *str; 302 const char *ret = p->buffer + p->len; 303 int i, first = 1; 304 305 for (i = 0; flag_array[i].name && flags; i++) { 306 307 mask = flag_array[i].mask; 308 if ((flags & mask) != mask) 309 continue; 310 311 str = flag_array[i].name; 312 flags &= ~mask; 313 if (!first && delim) 314 trace_seq_puts(p, delim); 315 else 316 first = 0; 317 trace_seq_puts(p, str); 318 } 319 320 /* check for left over flags */ 321 if (flags) { 322 if (!first && delim) 323 trace_seq_puts(p, delim); 324 trace_seq_printf(p, "0x%lx", flags); 325 } 326 327 trace_seq_putc(p, 0); 328 329 return ret; 330 } 331 EXPORT_SYMBOL(ftrace_print_flags_seq); 332 333 const char * 334 ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, 335 const struct trace_print_flags *symbol_array) 336 { 337 int i; 338 const char *ret = p->buffer + p->len; 339 340 for (i = 0; symbol_array[i].name; i++) { 341 342 if (val != symbol_array[i].mask) 343 continue; 344 345 trace_seq_puts(p, symbol_array[i].name); 346 break; 347 } 348 349 if (ret == (const char *)(p->buffer + p->len)) 350 trace_seq_printf(p, "0x%lx", val); 351 352 trace_seq_putc(p, 0); 353 354 return ret; 355 } 356 EXPORT_SYMBOL(ftrace_print_symbols_seq); 357 358 #if BITS_PER_LONG == 32 359 const char * 360 ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, 361 const struct trace_print_flags_u64 *symbol_array) 362 { 363 int i; 364 const char *ret = p->buffer + p->len; 365 366 for (i = 0; symbol_array[i].name; i++) { 367 368 if (val != symbol_array[i].mask) 369 continue; 370 371 trace_seq_puts(p, symbol_array[i].name); 372 break; 373 } 374 375 if (ret == (const char *)(p->buffer + p->len)) 376 trace_seq_printf(p, "0x%llx", val); 377 378 trace_seq_putc(p, 0); 379 380 return ret; 381 } 382 EXPORT_SYMBOL(ftrace_print_symbols_seq_u64); 383 #endif 384 385 const char * 386 ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len) 387 { 388 int i; 389 const char *ret = p->buffer + p->len; 390 391 for (i = 0; i < buf_len; i++) 392 trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]); 393 394 trace_seq_putc(p, 0); 395 396 return ret; 397 } 398 EXPORT_SYMBOL(ftrace_print_hex_seq); 399 400 #ifdef CONFIG_KRETPROBES 401 static inline const char *kretprobed(const char *name) 402 { 403 static const char tramp_name[] = "kretprobe_trampoline"; 404 int size = sizeof(tramp_name); 405 406 if (strncmp(tramp_name, name, size) == 0) 407 return "[unknown/kretprobe'd]"; 408 return name; 409 } 410 #else 411 static inline const char *kretprobed(const char *name) 412 { 413 return name; 414 } 415 #endif /* CONFIG_KRETPROBES */ 416 417 static int 418 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) 419 { 420 #ifdef CONFIG_KALLSYMS 421 char str[KSYM_SYMBOL_LEN]; 422 const char *name; 423 424 kallsyms_lookup(address, NULL, NULL, NULL, str); 425 426 name = kretprobed(str); 427 428 return trace_seq_printf(s, fmt, name); 429 #endif 430 return 1; 431 } 432 433 static int 434 seq_print_sym_offset(struct trace_seq *s, const char *fmt, 435 unsigned long address) 436 { 437 #ifdef CONFIG_KALLSYMS 438 char str[KSYM_SYMBOL_LEN]; 439 const char *name; 440 441 sprint_symbol(str, address); 442 name = kretprobed(str); 443 444 return trace_seq_printf(s, fmt, name); 445 #endif 446 return 1; 447 } 448 449 #ifndef CONFIG_64BIT 450 # define IP_FMT "%08lx" 451 #else 452 # define IP_FMT "%016lx" 453 #endif 454 455 int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, 456 unsigned long ip, unsigned long sym_flags) 457 { 458 struct file *file = NULL; 459 unsigned long vmstart = 0; 460 int ret = 1; 461 462 if (s->full) 463 return 0; 464 465 if (mm) { 466 const struct vm_area_struct *vma; 467 468 down_read(&mm->mmap_sem); 469 vma = find_vma(mm, ip); 470 if (vma) { 471 file = vma->vm_file; 472 vmstart = vma->vm_start; 473 } 474 if (file) { 475 ret = trace_seq_path(s, &file->f_path); 476 if (ret) 477 ret = trace_seq_printf(s, "[+0x%lx]", 478 ip - vmstart); 479 } 480 up_read(&mm->mmap_sem); 481 } 482 if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file)) 483 ret = trace_seq_printf(s, " <" IP_FMT ">", ip); 484 return ret; 485 } 486 487 int 488 seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s, 489 unsigned long sym_flags) 490 { 491 struct mm_struct *mm = NULL; 492 int ret = 1; 493 unsigned int i; 494 495 if (trace_flags & TRACE_ITER_SYM_USEROBJ) { 496 struct task_struct *task; 497 /* 498 * we do the lookup on the thread group leader, 499 * since individual threads might have already quit! 500 */ 501 rcu_read_lock(); 502 task = find_task_by_vpid(entry->tgid); 503 if (task) 504 mm = get_task_mm(task); 505 rcu_read_unlock(); 506 } 507 508 for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { 509 unsigned long ip = entry->caller[i]; 510 511 if (ip == ULONG_MAX || !ret) 512 break; 513 if (ret) 514 ret = trace_seq_puts(s, " => "); 515 if (!ip) { 516 if (ret) 517 ret = trace_seq_puts(s, "??"); 518 if (ret) 519 ret = trace_seq_puts(s, "\n"); 520 continue; 521 } 522 if (!ret) 523 break; 524 if (ret) 525 ret = seq_print_user_ip(s, mm, ip, sym_flags); 526 ret = trace_seq_puts(s, "\n"); 527 } 528 529 if (mm) 530 mmput(mm); 531 return ret; 532 } 533 534 int 535 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) 536 { 537 int ret; 538 539 if (!ip) 540 return trace_seq_printf(s, "0"); 541 542 if (sym_flags & TRACE_ITER_SYM_OFFSET) 543 ret = seq_print_sym_offset(s, "%s", ip); 544 else 545 ret = seq_print_sym_short(s, "%s", ip); 546 547 if (!ret) 548 return 0; 549 550 if (sym_flags & TRACE_ITER_SYM_ADDR) 551 ret = trace_seq_printf(s, " <" IP_FMT ">", ip); 552 return ret; 553 } 554 555 /** 556 * trace_print_lat_fmt - print the irq, preempt and lockdep fields 557 * @s: trace seq struct to write to 558 * @entry: The trace entry field from the ring buffer 559 * 560 * Prints the generic fields of irqs off, in hard or softirq, preempt 561 * count. 562 */ 563 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry) 564 { 565 char hardsoft_irq; 566 char need_resched; 567 char irqs_off; 568 int hardirq; 569 int softirq; 570 int ret; 571 572 hardirq = entry->flags & TRACE_FLAG_HARDIRQ; 573 softirq = entry->flags & TRACE_FLAG_SOFTIRQ; 574 575 irqs_off = 576 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : 577 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' : 578 '.'; 579 need_resched = 580 (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.'; 581 hardsoft_irq = 582 (hardirq && softirq) ? 'H' : 583 hardirq ? 'h' : 584 softirq ? 's' : 585 '.'; 586 587 if (!trace_seq_printf(s, "%c%c%c", 588 irqs_off, need_resched, hardsoft_irq)) 589 return 0; 590 591 if (entry->preempt_count) 592 ret = trace_seq_printf(s, "%x", entry->preempt_count); 593 else 594 ret = trace_seq_putc(s, '.'); 595 596 return ret; 597 } 598 599 static int 600 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) 601 { 602 char comm[TASK_COMM_LEN]; 603 604 trace_find_cmdline(entry->pid, comm); 605 606 if (!trace_seq_printf(s, "%8.8s-%-5d %3d", 607 comm, entry->pid, cpu)) 608 return 0; 609 610 return trace_print_lat_fmt(s, entry); 611 } 612 613 static unsigned long preempt_mark_thresh = 100; 614 615 static int 616 lat_print_timestamp(struct trace_seq *s, u64 abs_usecs, 617 unsigned long rel_usecs) 618 { 619 return trace_seq_printf(s, " %4lldus%c: ", abs_usecs, 620 rel_usecs > preempt_mark_thresh ? '!' : 621 rel_usecs > 1 ? '+' : ' '); 622 } 623 624 int trace_print_context(struct trace_iterator *iter) 625 { 626 struct trace_seq *s = &iter->seq; 627 struct trace_entry *entry = iter->ent; 628 unsigned long long t = ns2usecs(iter->ts); 629 unsigned long usec_rem = do_div(t, USEC_PER_SEC); 630 unsigned long secs = (unsigned long)t; 631 char comm[TASK_COMM_LEN]; 632 int ret; 633 634 trace_find_cmdline(entry->pid, comm); 635 636 ret = trace_seq_printf(s, "%16s-%-5d [%03d] ", 637 comm, entry->pid, iter->cpu); 638 if (!ret) 639 return 0; 640 641 if (trace_flags & TRACE_ITER_IRQ_INFO) { 642 ret = trace_print_lat_fmt(s, entry); 643 if (!ret) 644 return 0; 645 } 646 647 return trace_seq_printf(s, " %5lu.%06lu: ", 648 secs, usec_rem); 649 } 650 651 int trace_print_lat_context(struct trace_iterator *iter) 652 { 653 u64 next_ts; 654 int ret; 655 struct trace_seq *s = &iter->seq; 656 struct trace_entry *entry = iter->ent, 657 *next_entry = trace_find_next_entry(iter, NULL, 658 &next_ts); 659 unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); 660 unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start); 661 unsigned long rel_usecs; 662 663 if (!next_entry) 664 next_ts = iter->ts; 665 rel_usecs = ns2usecs(next_ts - iter->ts); 666 667 if (verbose) { 668 char comm[TASK_COMM_LEN]; 669 670 trace_find_cmdline(entry->pid, comm); 671 672 ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]" 673 " %ld.%03ldms (+%ld.%03ldms): ", comm, 674 entry->pid, iter->cpu, entry->flags, 675 entry->preempt_count, iter->idx, 676 ns2usecs(iter->ts), 677 abs_usecs / USEC_PER_MSEC, 678 abs_usecs % USEC_PER_MSEC, 679 rel_usecs / USEC_PER_MSEC, 680 rel_usecs % USEC_PER_MSEC); 681 } else { 682 ret = lat_print_generic(s, entry, iter->cpu); 683 if (ret) 684 ret = lat_print_timestamp(s, abs_usecs, rel_usecs); 685 } 686 687 return ret; 688 } 689 690 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; 691 692 static int task_state_char(unsigned long state) 693 { 694 int bit = state ? __ffs(state) + 1 : 0; 695 696 return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?'; 697 } 698 699 /** 700 * ftrace_find_event - find a registered event 701 * @type: the type of event to look for 702 * 703 * Returns an event of type @type otherwise NULL 704 * Called with trace_event_read_lock() held. 705 */ 706 struct trace_event *ftrace_find_event(int type) 707 { 708 struct trace_event *event; 709 struct hlist_node *n; 710 unsigned key; 711 712 key = type & (EVENT_HASHSIZE - 1); 713 714 hlist_for_each_entry(event, n, &event_hash[key], node) { 715 if (event->type == type) 716 return event; 717 } 718 719 return NULL; 720 } 721 722 static LIST_HEAD(ftrace_event_list); 723 724 static int trace_search_list(struct list_head **list) 725 { 726 struct trace_event *e; 727 int last = __TRACE_LAST_TYPE; 728 729 if (list_empty(&ftrace_event_list)) { 730 *list = &ftrace_event_list; 731 return last + 1; 732 } 733 734 /* 735 * We used up all possible max events, 736 * lets see if somebody freed one. 737 */ 738 list_for_each_entry(e, &ftrace_event_list, list) { 739 if (e->type != last + 1) 740 break; 741 last++; 742 } 743 744 /* Did we used up all 65 thousand events??? */ 745 if ((last + 1) > FTRACE_MAX_EVENT) 746 return 0; 747 748 *list = &e->list; 749 return last + 1; 750 } 751 752 void trace_event_read_lock(void) 753 { 754 down_read(&trace_event_mutex); 755 } 756 757 void trace_event_read_unlock(void) 758 { 759 up_read(&trace_event_mutex); 760 } 761 762 /** 763 * register_ftrace_event - register output for an event type 764 * @event: the event type to register 765 * 766 * Event types are stored in a hash and this hash is used to 767 * find a way to print an event. If the @event->type is set 768 * then it will use that type, otherwise it will assign a 769 * type to use. 770 * 771 * If you assign your own type, please make sure it is added 772 * to the trace_type enum in trace.h, to avoid collisions 773 * with the dynamic types. 774 * 775 * Returns the event type number or zero on error. 776 */ 777 int register_ftrace_event(struct trace_event *event) 778 { 779 unsigned key; 780 int ret = 0; 781 782 down_write(&trace_event_mutex); 783 784 if (WARN_ON(!event)) 785 goto out; 786 787 if (WARN_ON(!event->funcs)) 788 goto out; 789 790 INIT_LIST_HEAD(&event->list); 791 792 if (!event->type) { 793 struct list_head *list = NULL; 794 795 if (next_event_type > FTRACE_MAX_EVENT) { 796 797 event->type = trace_search_list(&list); 798 if (!event->type) 799 goto out; 800 801 } else { 802 803 event->type = next_event_type++; 804 list = &ftrace_event_list; 805 } 806 807 if (WARN_ON(ftrace_find_event(event->type))) 808 goto out; 809 810 list_add_tail(&event->list, list); 811 812 } else if (event->type > __TRACE_LAST_TYPE) { 813 printk(KERN_WARNING "Need to add type to trace.h\n"); 814 WARN_ON(1); 815 goto out; 816 } else { 817 /* Is this event already used */ 818 if (ftrace_find_event(event->type)) 819 goto out; 820 } 821 822 if (event->funcs->trace == NULL) 823 event->funcs->trace = trace_nop_print; 824 if (event->funcs->raw == NULL) 825 event->funcs->raw = trace_nop_print; 826 if (event->funcs->hex == NULL) 827 event->funcs->hex = trace_nop_print; 828 if (event->funcs->binary == NULL) 829 event->funcs->binary = trace_nop_print; 830 831 key = event->type & (EVENT_HASHSIZE - 1); 832 833 hlist_add_head(&event->node, &event_hash[key]); 834 835 ret = event->type; 836 out: 837 up_write(&trace_event_mutex); 838 839 return ret; 840 } 841 EXPORT_SYMBOL_GPL(register_ftrace_event); 842 843 /* 844 * Used by module code with the trace_event_mutex held for write. 845 */ 846 int __unregister_ftrace_event(struct trace_event *event) 847 { 848 hlist_del(&event->node); 849 list_del(&event->list); 850 return 0; 851 } 852 853 /** 854 * unregister_ftrace_event - remove a no longer used event 855 * @event: the event to remove 856 */ 857 int unregister_ftrace_event(struct trace_event *event) 858 { 859 down_write(&trace_event_mutex); 860 __unregister_ftrace_event(event); 861 up_write(&trace_event_mutex); 862 863 return 0; 864 } 865 EXPORT_SYMBOL_GPL(unregister_ftrace_event); 866 867 /* 868 * Standard events 869 */ 870 871 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags, 872 struct trace_event *event) 873 { 874 if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type)) 875 return TRACE_TYPE_PARTIAL_LINE; 876 877 return TRACE_TYPE_HANDLED; 878 } 879 880 /* TRACE_FN */ 881 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags, 882 struct trace_event *event) 883 { 884 struct ftrace_entry *field; 885 struct trace_seq *s = &iter->seq; 886 887 trace_assign_type(field, iter->ent); 888 889 if (!seq_print_ip_sym(s, field->ip, flags)) 890 goto partial; 891 892 if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) { 893 if (!trace_seq_printf(s, " <-")) 894 goto partial; 895 if (!seq_print_ip_sym(s, 896 field->parent_ip, 897 flags)) 898 goto partial; 899 } 900 if (!trace_seq_printf(s, "\n")) 901 goto partial; 902 903 return TRACE_TYPE_HANDLED; 904 905 partial: 906 return TRACE_TYPE_PARTIAL_LINE; 907 } 908 909 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags, 910 struct trace_event *event) 911 { 912 struct ftrace_entry *field; 913 914 trace_assign_type(field, iter->ent); 915 916 if (!trace_seq_printf(&iter->seq, "%lx %lx\n", 917 field->ip, 918 field->parent_ip)) 919 return TRACE_TYPE_PARTIAL_LINE; 920 921 return TRACE_TYPE_HANDLED; 922 } 923 924 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags, 925 struct trace_event *event) 926 { 927 struct ftrace_entry *field; 928 struct trace_seq *s = &iter->seq; 929 930 trace_assign_type(field, iter->ent); 931 932 SEQ_PUT_HEX_FIELD_RET(s, field->ip); 933 SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip); 934 935 return TRACE_TYPE_HANDLED; 936 } 937 938 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags, 939 struct trace_event *event) 940 { 941 struct ftrace_entry *field; 942 struct trace_seq *s = &iter->seq; 943 944 trace_assign_type(field, iter->ent); 945 946 SEQ_PUT_FIELD_RET(s, field->ip); 947 SEQ_PUT_FIELD_RET(s, field->parent_ip); 948 949 return TRACE_TYPE_HANDLED; 950 } 951 952 static struct trace_event_functions trace_fn_funcs = { 953 .trace = trace_fn_trace, 954 .raw = trace_fn_raw, 955 .hex = trace_fn_hex, 956 .binary = trace_fn_bin, 957 }; 958 959 static struct trace_event trace_fn_event = { 960 .type = TRACE_FN, 961 .funcs = &trace_fn_funcs, 962 }; 963 964 /* TRACE_CTX an TRACE_WAKE */ 965 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter, 966 char *delim) 967 { 968 struct ctx_switch_entry *field; 969 char comm[TASK_COMM_LEN]; 970 int S, T; 971 972 973 trace_assign_type(field, iter->ent); 974 975 T = task_state_char(field->next_state); 976 S = task_state_char(field->prev_state); 977 trace_find_cmdline(field->next_pid, comm); 978 if (!trace_seq_printf(&iter->seq, 979 " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n", 980 field->prev_pid, 981 field->prev_prio, 982 S, delim, 983 field->next_cpu, 984 field->next_pid, 985 field->next_prio, 986 T, comm)) 987 return TRACE_TYPE_PARTIAL_LINE; 988 989 return TRACE_TYPE_HANDLED; 990 } 991 992 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags, 993 struct trace_event *event) 994 { 995 return trace_ctxwake_print(iter, "==>"); 996 } 997 998 static enum print_line_t trace_wake_print(struct trace_iterator *iter, 999 int flags, struct trace_event *event) 1000 { 1001 return trace_ctxwake_print(iter, " +"); 1002 } 1003 1004 static int trace_ctxwake_raw(struct trace_iterator *iter, char S) 1005 { 1006 struct ctx_switch_entry *field; 1007 int T; 1008 1009 trace_assign_type(field, iter->ent); 1010 1011 if (!S) 1012 S = task_state_char(field->prev_state); 1013 T = task_state_char(field->next_state); 1014 if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n", 1015 field->prev_pid, 1016 field->prev_prio, 1017 S, 1018 field->next_cpu, 1019 field->next_pid, 1020 field->next_prio, 1021 T)) 1022 return TRACE_TYPE_PARTIAL_LINE; 1023 1024 return TRACE_TYPE_HANDLED; 1025 } 1026 1027 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags, 1028 struct trace_event *event) 1029 { 1030 return trace_ctxwake_raw(iter, 0); 1031 } 1032 1033 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags, 1034 struct trace_event *event) 1035 { 1036 return trace_ctxwake_raw(iter, '+'); 1037 } 1038 1039 1040 static int trace_ctxwake_hex(struct trace_iterator *iter, char S) 1041 { 1042 struct ctx_switch_entry *field; 1043 struct trace_seq *s = &iter->seq; 1044 int T; 1045 1046 trace_assign_type(field, iter->ent); 1047 1048 if (!S) 1049 S = task_state_char(field->prev_state); 1050 T = task_state_char(field->next_state); 1051 1052 SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid); 1053 SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio); 1054 SEQ_PUT_HEX_FIELD_RET(s, S); 1055 SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu); 1056 SEQ_PUT_HEX_FIELD_RET(s, field->next_pid); 1057 SEQ_PUT_HEX_FIELD_RET(s, field->next_prio); 1058 SEQ_PUT_HEX_FIELD_RET(s, T); 1059 1060 return TRACE_TYPE_HANDLED; 1061 } 1062 1063 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags, 1064 struct trace_event *event) 1065 { 1066 return trace_ctxwake_hex(iter, 0); 1067 } 1068 1069 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags, 1070 struct trace_event *event) 1071 { 1072 return trace_ctxwake_hex(iter, '+'); 1073 } 1074 1075 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter, 1076 int flags, struct trace_event *event) 1077 { 1078 struct ctx_switch_entry *field; 1079 struct trace_seq *s = &iter->seq; 1080 1081 trace_assign_type(field, iter->ent); 1082 1083 SEQ_PUT_FIELD_RET(s, field->prev_pid); 1084 SEQ_PUT_FIELD_RET(s, field->prev_prio); 1085 SEQ_PUT_FIELD_RET(s, field->prev_state); 1086 SEQ_PUT_FIELD_RET(s, field->next_pid); 1087 SEQ_PUT_FIELD_RET(s, field->next_prio); 1088 SEQ_PUT_FIELD_RET(s, field->next_state); 1089 1090 return TRACE_TYPE_HANDLED; 1091 } 1092 1093 static struct trace_event_functions trace_ctx_funcs = { 1094 .trace = trace_ctx_print, 1095 .raw = trace_ctx_raw, 1096 .hex = trace_ctx_hex, 1097 .binary = trace_ctxwake_bin, 1098 }; 1099 1100 static struct trace_event trace_ctx_event = { 1101 .type = TRACE_CTX, 1102 .funcs = &trace_ctx_funcs, 1103 }; 1104 1105 static struct trace_event_functions trace_wake_funcs = { 1106 .trace = trace_wake_print, 1107 .raw = trace_wake_raw, 1108 .hex = trace_wake_hex, 1109 .binary = trace_ctxwake_bin, 1110 }; 1111 1112 static struct trace_event trace_wake_event = { 1113 .type = TRACE_WAKE, 1114 .funcs = &trace_wake_funcs, 1115 }; 1116 1117 /* TRACE_STACK */ 1118 1119 static enum print_line_t trace_stack_print(struct trace_iterator *iter, 1120 int flags, struct trace_event *event) 1121 { 1122 struct stack_entry *field; 1123 struct trace_seq *s = &iter->seq; 1124 unsigned long *p; 1125 unsigned long *end; 1126 1127 trace_assign_type(field, iter->ent); 1128 end = (unsigned long *)((long)iter->ent + iter->ent_size); 1129 1130 if (!trace_seq_puts(s, "<stack trace>\n")) 1131 goto partial; 1132 1133 for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) { 1134 if (!trace_seq_puts(s, " => ")) 1135 goto partial; 1136 1137 if (!seq_print_ip_sym(s, *p, flags)) 1138 goto partial; 1139 if (!trace_seq_puts(s, "\n")) 1140 goto partial; 1141 } 1142 1143 return TRACE_TYPE_HANDLED; 1144 1145 partial: 1146 return TRACE_TYPE_PARTIAL_LINE; 1147 } 1148 1149 static struct trace_event_functions trace_stack_funcs = { 1150 .trace = trace_stack_print, 1151 }; 1152 1153 static struct trace_event trace_stack_event = { 1154 .type = TRACE_STACK, 1155 .funcs = &trace_stack_funcs, 1156 }; 1157 1158 /* TRACE_USER_STACK */ 1159 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter, 1160 int flags, struct trace_event *event) 1161 { 1162 struct userstack_entry *field; 1163 struct trace_seq *s = &iter->seq; 1164 1165 trace_assign_type(field, iter->ent); 1166 1167 if (!trace_seq_puts(s, "<user stack trace>\n")) 1168 goto partial; 1169 1170 if (!seq_print_userip_objs(field, s, flags)) 1171 goto partial; 1172 1173 return TRACE_TYPE_HANDLED; 1174 1175 partial: 1176 return TRACE_TYPE_PARTIAL_LINE; 1177 } 1178 1179 static struct trace_event_functions trace_user_stack_funcs = { 1180 .trace = trace_user_stack_print, 1181 }; 1182 1183 static struct trace_event trace_user_stack_event = { 1184 .type = TRACE_USER_STACK, 1185 .funcs = &trace_user_stack_funcs, 1186 }; 1187 1188 /* TRACE_BPRINT */ 1189 static enum print_line_t 1190 trace_bprint_print(struct trace_iterator *iter, int flags, 1191 struct trace_event *event) 1192 { 1193 struct trace_entry *entry = iter->ent; 1194 struct trace_seq *s = &iter->seq; 1195 struct bprint_entry *field; 1196 1197 trace_assign_type(field, entry); 1198 1199 if (!seq_print_ip_sym(s, field->ip, flags)) 1200 goto partial; 1201 1202 if (!trace_seq_puts(s, ": ")) 1203 goto partial; 1204 1205 if (!trace_seq_bprintf(s, field->fmt, field->buf)) 1206 goto partial; 1207 1208 return TRACE_TYPE_HANDLED; 1209 1210 partial: 1211 return TRACE_TYPE_PARTIAL_LINE; 1212 } 1213 1214 1215 static enum print_line_t 1216 trace_bprint_raw(struct trace_iterator *iter, int flags, 1217 struct trace_event *event) 1218 { 1219 struct bprint_entry *field; 1220 struct trace_seq *s = &iter->seq; 1221 1222 trace_assign_type(field, iter->ent); 1223 1224 if (!trace_seq_printf(s, ": %lx : ", field->ip)) 1225 goto partial; 1226 1227 if (!trace_seq_bprintf(s, field->fmt, field->buf)) 1228 goto partial; 1229 1230 return TRACE_TYPE_HANDLED; 1231 1232 partial: 1233 return TRACE_TYPE_PARTIAL_LINE; 1234 } 1235 1236 static struct trace_event_functions trace_bprint_funcs = { 1237 .trace = trace_bprint_print, 1238 .raw = trace_bprint_raw, 1239 }; 1240 1241 static struct trace_event trace_bprint_event = { 1242 .type = TRACE_BPRINT, 1243 .funcs = &trace_bprint_funcs, 1244 }; 1245 1246 /* TRACE_PRINT */ 1247 static enum print_line_t trace_print_print(struct trace_iterator *iter, 1248 int flags, struct trace_event *event) 1249 { 1250 struct print_entry *field; 1251 struct trace_seq *s = &iter->seq; 1252 1253 trace_assign_type(field, iter->ent); 1254 1255 if (!seq_print_ip_sym(s, field->ip, flags)) 1256 goto partial; 1257 1258 if (!trace_seq_printf(s, ": %s", field->buf)) 1259 goto partial; 1260 1261 return TRACE_TYPE_HANDLED; 1262 1263 partial: 1264 return TRACE_TYPE_PARTIAL_LINE; 1265 } 1266 1267 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags, 1268 struct trace_event *event) 1269 { 1270 struct print_entry *field; 1271 1272 trace_assign_type(field, iter->ent); 1273 1274 if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf)) 1275 goto partial; 1276 1277 return TRACE_TYPE_HANDLED; 1278 1279 partial: 1280 return TRACE_TYPE_PARTIAL_LINE; 1281 } 1282 1283 static struct trace_event_functions trace_print_funcs = { 1284 .trace = trace_print_print, 1285 .raw = trace_print_raw, 1286 }; 1287 1288 static struct trace_event trace_print_event = { 1289 .type = TRACE_PRINT, 1290 .funcs = &trace_print_funcs, 1291 }; 1292 1293 1294 static struct trace_event *events[] __initdata = { 1295 &trace_fn_event, 1296 &trace_ctx_event, 1297 &trace_wake_event, 1298 &trace_stack_event, 1299 &trace_user_stack_event, 1300 &trace_bprint_event, 1301 &trace_print_event, 1302 NULL 1303 }; 1304 1305 __init static int init_events(void) 1306 { 1307 struct trace_event *event; 1308 int i, ret; 1309 1310 for (i = 0; events[i]; i++) { 1311 event = events[i]; 1312 1313 ret = register_ftrace_event(event); 1314 if (!ret) { 1315 printk(KERN_WARNING "event %d failed to register\n", 1316 event->type); 1317 WARN_ON_ONCE(1); 1318 } 1319 } 1320 1321 return 0; 1322 } 1323 device_initcall(init_events); 1324