kernel/trace/trace_output.c

   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_sem);
  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 enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
  24 {
  25         struct trace_seq *s = &iter->seq;
  26         struct trace_entry *entry = iter->ent;
  27         struct bputs_entry *field;
  28
  29         trace_assign_type(field, entry);
  30
  31         trace_seq_puts(s, field->str);
  32
  33         return trace_handle_return(s);
  34 }
  35
  36 enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
  37 {
  38         struct trace_seq *s = &iter->seq;
  39         struct trace_entry *entry = iter->ent;
  40         struct bprint_entry *field;
  41
  42         trace_assign_type(field, entry);
  43
  44         trace_seq_bprintf(s, field->fmt, field->buf);
  45
  46         return trace_handle_return(s);
  47 }
  48
  49 enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
  50 {
  51         struct trace_seq *s = &iter->seq;
  52         struct trace_entry *entry = iter->ent;
  53         struct print_entry *field;
  54
  55         trace_assign_type(field, entry);
  56
  57         trace_seq_puts(s, field->buf);
  58
  59         return trace_handle_return(s);
  60 }
  61
  62 const char *
  63 trace_print_flags_seq(struct trace_seq *p, const char *delim,
  64                       unsigned long flags,
  65                       const struct trace_print_flags *flag_array)
  66 {
  67         unsigned long mask;
  68         const char *str;
  69         const char *ret = trace_seq_buffer_ptr(p);
  70         int i, first = 1;
  71
  72         for (i = 0;  flag_array[i].name && flags; i++) {
  73
  74                 mask = flag_array[i].mask;
  75                 if ((flags & mask) != mask)
  76                         continue;
  77
  78                 str = flag_array[i].name;
  79                 flags &= ~mask;
  80                 if (!first && delim)
  81                         trace_seq_puts(p, delim);
  82                 else
  83                         first = 0;
  84                 trace_seq_puts(p, str);
  85         }
  86
  87         /* check for left over flags */
  88         if (flags) {
  89                 if (!first && delim)
  90                         trace_seq_puts(p, delim);
  91                 trace_seq_printf(p, "0x%lx", flags);
  92         }
  93
  94         trace_seq_putc(p, 0);
  95
  96         return ret;
  97 }
  98 EXPORT_SYMBOL(trace_print_flags_seq);
  99
 100 const char *
 101 trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
 102                         const struct trace_print_flags *symbol_array)
 103 {
 104         int i;
 105         const char *ret = trace_seq_buffer_ptr(p);
 106
 107         for (i = 0;  symbol_array[i].name; i++) {
 108
 109                 if (val != symbol_array[i].mask)
 110                         continue;
 111
 112                 trace_seq_puts(p, symbol_array[i].name);
 113                 break;
 114         }
 115
 116         if (ret == (const char *)(trace_seq_buffer_ptr(p)))
 117                 trace_seq_printf(p, "0x%lx", val);
 118
 119         trace_seq_putc(p, 0);
 120
 121         return ret;
 122 }
 123 EXPORT_SYMBOL(trace_print_symbols_seq);
 124
 125 #if BITS_PER_LONG == 32
 126 const char *
 127 trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
 128                          const struct trace_print_flags_u64 *symbol_array)
 129 {
 130         int i;
 131         const char *ret = trace_seq_buffer_ptr(p);
 132
 133         for (i = 0;  symbol_array[i].name; i++) {
 134
 135                 if (val != symbol_array[i].mask)
 136                         continue;
 137
 138                 trace_seq_puts(p, symbol_array[i].name);
 139                 break;
 140         }
 141
 142         if (ret == (const char *)(trace_seq_buffer_ptr(p)))
 143                 trace_seq_printf(p, "0x%llx", val);
 144
 145         trace_seq_putc(p, 0);
 146
 147         return ret;
 148 }
 149 EXPORT_SYMBOL(trace_print_symbols_seq_u64);
 150 #endif
 151
 152 const char *
 153 trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
 154                         unsigned int bitmask_size)
 155 {
 156         const char *ret = trace_seq_buffer_ptr(p);
 157
 158         trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
 159         trace_seq_putc(p, 0);
 160
 161         return ret;
 162 }
 163 EXPORT_SYMBOL_GPL(trace_print_bitmask_seq);
 164
 165 const char *
 166 trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
 167 {
 168         int i;
 169         const char *ret = trace_seq_buffer_ptr(p);
 170
 171         for (i = 0; i < buf_len; i++)
 172                 trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
 173
 174         trace_seq_putc(p, 0);
 175
 176         return ret;
 177 }
 178 EXPORT_SYMBOL(trace_print_hex_seq);
 179
 180 const char *
 181 trace_print_array_seq(struct trace_seq *p, const void *buf, int count,
 182                       size_t el_size)
 183 {
 184         const char *ret = trace_seq_buffer_ptr(p);
 185         const char *prefix = "";
 186         void *ptr = (void *)buf;
 187         size_t buf_len = count * el_size;
 188
 189         trace_seq_putc(p, '{');
 190
 191         while (ptr < buf + buf_len) {
 192                 switch (el_size) {
 193                 case 1:
 194                         trace_seq_printf(p, "%s0x%x", prefix,
 195                                          *(u8 *)ptr);
 196                         break;
 197                 case 2:
 198                         trace_seq_printf(p, "%s0x%x", prefix,
 199                                          *(u16 *)ptr);
 200                         break;
 201                 case 4:
 202                         trace_seq_printf(p, "%s0x%x", prefix,
 203                                          *(u32 *)ptr);
 204                         break;
 205                 case 8:
 206                         trace_seq_printf(p, "%s0x%llx", prefix,
 207                                          *(u64 *)ptr);
 208                         break;
 209                 default:
 210                         trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size,
 211                                          *(u8 *)ptr);
 212                         el_size = 1;
 213                 }
 214                 prefix = ",";
 215                 ptr += el_size;
 216         }
 217
 218         trace_seq_putc(p, '}');
 219         trace_seq_putc(p, 0);
 220
 221         return ret;
 222 }
 223 EXPORT_SYMBOL(trace_print_array_seq);
 224
 225 int trace_raw_output_prep(struct trace_iterator *iter,
 226                           struct trace_event *trace_event)
 227 {
 228         struct trace_event_call *event;
 229         struct trace_seq *s = &iter->seq;
 230         struct trace_seq *p = &iter->tmp_seq;
 231         struct trace_entry *entry;
 232
 233         event = container_of(trace_event, struct trace_event_call, event);
 234         entry = iter->ent;
 235
 236         if (entry->type != event->event.type) {
 237                 WARN_ON_ONCE(1);
 238                 return TRACE_TYPE_UNHANDLED;
 239         }
 240
 241         trace_seq_init(p);
 242         trace_seq_printf(s, "%s: ", trace_event_name(event));
 243
 244         return trace_handle_return(s);
 245 }
 246 EXPORT_SYMBOL(trace_raw_output_prep);
 247
 248 static int trace_output_raw(struct trace_iterator *iter, char *name,
 249                             char *fmt, va_list ap)
 250 {
 251         struct trace_seq *s = &iter->seq;
 252
 253         trace_seq_printf(s, "%s: ", name);
 254         trace_seq_vprintf(s, fmt, ap);
 255
 256         return trace_handle_return(s);
 257 }
 258
 259 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
 260 {
 261         va_list ap;
 262         int ret;
 263
 264         va_start(ap, fmt);
 265         ret = trace_output_raw(iter, name, fmt, ap);
 266         va_end(ap);
 267
 268         return ret;
 269 }
 270 EXPORT_SYMBOL_GPL(trace_output_call);
 271
 272 #ifdef CONFIG_KRETPROBES
 273 static inline const char *kretprobed(const char *name)
 274 {
 275         static const char tramp_name[] = "kretprobe_trampoline";
 276         int size = sizeof(tramp_name);
 277
 278         if (strncmp(tramp_name, name, size) == 0)
 279                 return "[unknown/kretprobe'd]";
 280         return name;
 281 }
 282 #else
 283 static inline const char *kretprobed(const char *name)
 284 {
 285         return name;
 286 }
 287 #endif /* CONFIG_KRETPROBES */
 288
 289 static void
 290 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
 291 {
 292 #ifdef CONFIG_KALLSYMS
 293         char str[KSYM_SYMBOL_LEN];
 294         const char *name;
 295
 296         kallsyms_lookup(address, NULL, NULL, NULL, str);
 297
 298         name = kretprobed(str);
 299
 300         trace_seq_printf(s, fmt, name);
 301 #endif
 302 }
 303
 304 static void
 305 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
 306                      unsigned long address)
 307 {
 308 #ifdef CONFIG_KALLSYMS
 309         char str[KSYM_SYMBOL_LEN];
 310         const char *name;
 311
 312         sprint_symbol(str, address);
 313         name = kretprobed(str);
 314
 315         trace_seq_printf(s, fmt, name);
 316 #endif
 317 }
 318
 319 #ifndef CONFIG_64BIT
 320 # define IP_FMT "%08lx"
 321 #else
 322 # define IP_FMT "%016lx"
 323 #endif
 324
 325 static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
 326                              unsigned long ip, unsigned long sym_flags)
 327 {
 328         struct file *file = NULL;
 329         unsigned long vmstart = 0;
 330         int ret = 1;
 331
 332         if (s->full)
 333                 return 0;
 334
 335         if (mm) {
 336                 const struct vm_area_struct *vma;
 337
 338                 down_read(&mm->mmap_sem);
 339                 vma = find_vma(mm, ip);
 340                 if (vma) {
 341                         file = vma->vm_file;
 342                         vmstart = vma->vm_start;
 343                 }
 344                 if (file) {
 345                         ret = trace_seq_path(s, &file->f_path);
 346                         if (ret)
 347                                 trace_seq_printf(s, "[+0x%lx]",
 348                                                  ip - vmstart);
 349                 }
 350                 up_read(&mm->mmap_sem);
 351         }
 352         if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
 353                 trace_seq_printf(s, " <" IP_FMT ">", ip);
 354         return !trace_seq_has_overflowed(s);
 355 }
 356
 357 int
 358 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 359 {
 360         if (!ip) {
 361                 trace_seq_putc(s, '0');
 362                 goto out;
 363         }
 364
 365         if (sym_flags & TRACE_ITER_SYM_OFFSET)
 366                 seq_print_sym_offset(s, "%s", ip);
 367         else
 368                 seq_print_sym_short(s, "%s", ip);
 369
 370         if (sym_flags & TRACE_ITER_SYM_ADDR)
 371                 trace_seq_printf(s, " <" IP_FMT ">", ip);
 372
 373  out:
 374         return !trace_seq_has_overflowed(s);
 375 }
 376
 377 /**
 378  * trace_print_lat_fmt - print the irq, preempt and lockdep fields
 379  * @s: trace seq struct to write to
 380  * @entry: The trace entry field from the ring buffer
 381  *
 382  * Prints the generic fields of irqs off, in hard or softirq, preempt
 383  * count.
 384  */
 385 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 386 {
 387         char hardsoft_irq;
 388         char need_resched;
 389         char irqs_off;
 390         int hardirq;
 391         int softirq;
 392
 393         hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 394         softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 395
 396         irqs_off =
 397                 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 398                 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 399                 '.';
 400
 401         switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
 402                                 TRACE_FLAG_PREEMPT_RESCHED)) {
 403         case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 404                 need_resched = 'N';
 405                 break;
 406         case TRACE_FLAG_NEED_RESCHED:
 407                 need_resched = 'n';
 408                 break;
 409         case TRACE_FLAG_PREEMPT_RESCHED:
 410                 need_resched = 'p';
 411                 break;
 412         default:
 413                 need_resched = '.';
 414                 break;
 415         }
 416
 417         hardsoft_irq =
 418                 (hardirq && softirq) ? 'H' :
 419                 hardirq ? 'h' :
 420                 softirq ? 's' :
 421                 '.';
 422
 423         trace_seq_printf(s, "%c%c%c",
 424                          irqs_off, need_resched, hardsoft_irq);
 425
 426         if (entry->preempt_count)
 427                 trace_seq_printf(s, "%x", entry->preempt_count);
 428         else
 429                 trace_seq_putc(s, '.');
 430
 431         return !trace_seq_has_overflowed(s);
 432 }
 433
 434 static int
 435 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 436 {
 437         char comm[TASK_COMM_LEN];
 438
 439         trace_find_cmdline(entry->pid, comm);
 440
 441         trace_seq_printf(s, "%8.8s-%-5d %3d",
 442                          comm, entry->pid, cpu);
 443
 444         return trace_print_lat_fmt(s, entry);
 445 }
 446
 447 #undef MARK
 448 #define MARK(v, s) {.val = v, .sym = s}
 449 /* trace overhead mark */
 450 static const struct trace_mark {
 451         unsigned long long      val; /* unit: nsec */
 452         char                    sym;
 453 } mark[] = {
 454         MARK(1000000000ULL      , '$'), /* 1 sec */
 455         MARK(100000000ULL       , '@'), /* 100 msec */
 456         MARK(10000000ULL        , '*'), /* 10 msec */
 457         MARK(1000000ULL         , '#'), /* 1000 usecs */
 458         MARK(100000ULL          , '!'), /* 100 usecs */
 459         MARK(10000ULL           , '+'), /* 10 usecs */
 460 };
 461 #undef MARK
 462
 463 char trace_find_mark(unsigned long long d)
 464 {
 465         int i;
 466         int size = ARRAY_SIZE(mark);
 467
 468         for (i = 0; i < size; i++) {
 469                 if (d > mark[i].val)
 470                         break;
 471         }
 472
 473         return (i == size) ? ' ' : mark[i].sym;
 474 }
 475
 476 static int
 477 lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
 478 {
 479         struct trace_array *tr = iter->tr;
 480         unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE;
 481         unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
 482         unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start;
 483         unsigned long long rel_ts = next_ts - iter->ts;
 484         struct trace_seq *s = &iter->seq;
 485
 486         if (in_ns) {
 487                 abs_ts = ns2usecs(abs_ts);
 488                 rel_ts = ns2usecs(rel_ts);
 489         }
 490
 491         if (verbose && in_ns) {
 492                 unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
 493                 unsigned long abs_msec = (unsigned long)abs_ts;
 494                 unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
 495                 unsigned long rel_msec = (unsigned long)rel_ts;
 496
 497                 trace_seq_printf(
 498                         s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
 499                         ns2usecs(iter->ts),
 500                         abs_msec, abs_usec,
 501                         rel_msec, rel_usec);
 502
 503         } else if (verbose && !in_ns) {
 504                 trace_seq_printf(
 505                         s, "[%016llx] %lld (+%lld): ",
 506                         iter->ts, abs_ts, rel_ts);
 507
 508         } else if (!verbose && in_ns) {
 509                 trace_seq_printf(
 510                         s, " %4lldus%c: ",
 511                         abs_ts,
 512                         trace_find_mark(rel_ts * NSEC_PER_USEC));
 513
 514         } else { /* !verbose && !in_ns */
 515                 trace_seq_printf(s, " %4lld: ", abs_ts);
 516         }
 517
 518         return !trace_seq_has_overflowed(s);
 519 }
 520
 521 int trace_print_context(struct trace_iterator *iter)
 522 {
 523         struct trace_array *tr = iter->tr;
 524         struct trace_seq *s = &iter->seq;
 525         struct trace_entry *entry = iter->ent;
 526         unsigned long long t;
 527         unsigned long secs, usec_rem;
 528         char comm[TASK_COMM_LEN];
 529         int tgid;
 530
 531         trace_find_cmdline(entry->pid, comm);
 532
 533         trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid);
 534
 535         if (tr->trace_flags & TRACE_ITER_TGID) {
 536                 tgid = trace_find_tgid(entry->pid);
 537                 if (tgid < 0)
 538                         trace_seq_puts(s, "(-----) ");
 539                 else
 540                         trace_seq_printf(s, "(%5d) ", tgid);
 541         }
 542
 543         trace_seq_printf(s, "[%03d] ", iter->cpu);
 544
 545         if (tr->trace_flags & TRACE_ITER_IRQ_INFO)
 546                 trace_print_lat_fmt(s, entry);
 547
 548         if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
 549                 t = ns2usecs(iter->ts);
 550                 usec_rem = do_div(t, USEC_PER_SEC);
 551                 secs = (unsigned long)t;
 552                 trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
 553         } else
 554                 trace_seq_printf(s, " %12llu: ", iter->ts);
 555
 556         return !trace_seq_has_overflowed(s);
 557 }
 558
 559 int trace_print_lat_context(struct trace_iterator *iter)
 560 {
 561         struct trace_array *tr = iter->tr;
 562         /* trace_find_next_entry will reset ent_size */
 563         int ent_size = iter->ent_size;
 564         struct trace_seq *s = &iter->seq;
 565         u64 next_ts;
 566         struct trace_entry *entry = iter->ent,
 567                            *next_entry = trace_find_next_entry(iter, NULL,
 568                                                                &next_ts);
 569         unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE);
 570
 571         /* Restore the original ent_size */
 572         iter->ent_size = ent_size;
 573
 574         if (!next_entry)
 575                 next_ts = iter->ts;
 576
 577         if (verbose) {
 578                 char comm[TASK_COMM_LEN];
 579
 580                 trace_find_cmdline(entry->pid, comm);
 581
 582                 trace_seq_printf(
 583                         s, "%16s %5d %3d %d %08x %08lx ",
 584                         comm, entry->pid, iter->cpu, entry->flags,
 585                         entry->preempt_count, iter->idx);
 586         } else {
 587                 lat_print_generic(s, entry, iter->cpu);
 588         }
 589
 590         lat_print_timestamp(iter, next_ts);
 591
 592         return !trace_seq_has_overflowed(s);
 593 }
 594
 595 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
 596
 597 static int task_state_char(unsigned long state)
 598 {
 599         int bit = state ? __ffs(state) + 1 : 0;
 600
 601         return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
 602 }
 603
 604 /**
 605  * ftrace_find_event - find a registered event
 606  * @type: the type of event to look for
 607  *
 608  * Returns an event of type @type otherwise NULL
 609  * Called with trace_event_read_lock() held.
 610  */
 611 struct trace_event *ftrace_find_event(int type)
 612 {
 613         struct trace_event *event;
 614         unsigned key;
 615
 616         key = type & (EVENT_HASHSIZE - 1);
 617
 618         hlist_for_each_entry(event, &event_hash[key], node) {
 619                 if (event->type == type)
 620                         return event;
 621         }
 622
 623         return NULL;
 624 }
 625
 626 static LIST_HEAD(ftrace_event_list);
 627
 628 static int trace_search_list(struct list_head **list)
 629 {
 630         struct trace_event *e;
 631         int last = __TRACE_LAST_TYPE;
 632
 633         if (list_empty(&ftrace_event_list)) {
 634                 *list = &ftrace_event_list;
 635                 return last + 1;
 636         }
 637
 638         /*
 639          * We used up all possible max events,
 640          * lets see if somebody freed one.
 641          */
 642         list_for_each_entry(e, &ftrace_event_list, list) {
 643                 if (e->type != last + 1)
 644                         break;
 645                 last++;
 646         }
 647
 648         /* Did we used up all 65 thousand events??? */
 649         if ((last + 1) > TRACE_EVENT_TYPE_MAX)
 650                 return 0;
 651
 652         *list = &e->list;
 653         return last + 1;
 654 }
 655
 656 void trace_event_read_lock(void)
 657 {
 658         down_read(&trace_event_sem);
 659 }
 660
 661 void trace_event_read_unlock(void)
 662 {
 663         up_read(&trace_event_sem);
 664 }
 665
 666 /**
 667  * register_trace_event - register output for an event type
 668  * @event: the event type to register
 669  *
 670  * Event types are stored in a hash and this hash is used to
 671  * find a way to print an event. If the @event->type is set
 672  * then it will use that type, otherwise it will assign a
 673  * type to use.
 674  *
 675  * If you assign your own type, please make sure it is added
 676  * to the trace_type enum in trace.h, to avoid collisions
 677  * with the dynamic types.
 678  *
 679  * Returns the event type number or zero on error.
 680  */
 681 int register_trace_event(struct trace_event *event)
 682 {
 683         unsigned key;
 684         int ret = 0;
 685
 686         down_write(&trace_event_sem);
 687
 688         if (WARN_ON(!event))
 689                 goto out;
 690
 691         if (WARN_ON(!event->funcs))
 692                 goto out;
 693
 694         INIT_LIST_HEAD(&event->list);
 695
 696         if (!event->type) {
 697                 struct list_head *list = NULL;
 698
 699                 if (next_event_type > TRACE_EVENT_TYPE_MAX) {
 700
 701                         event->type = trace_search_list(&list);
 702                         if (!event->type)
 703                                 goto out;
 704
 705                 } else {
 706
 707                         event->type = next_event_type++;
 708                         list = &ftrace_event_list;
 709                 }
 710
 711                 if (WARN_ON(ftrace_find_event(event->type)))
 712                         goto out;
 713
 714                 list_add_tail(&event->list, list);
 715
 716         } else if (event->type > __TRACE_LAST_TYPE) {
 717                 printk(KERN_WARNING "Need to add type to trace.h\n");
 718                 WARN_ON(1);
 719                 goto out;
 720         } else {
 721                 /* Is this event already used */
 722                 if (ftrace_find_event(event->type))
 723                         goto out;
 724         }
 725
 726         if (event->funcs->trace == NULL)
 727                 event->funcs->trace = trace_nop_print;
 728         if (event->funcs->raw == NULL)
 729                 event->funcs->raw = trace_nop_print;
 730         if (event->funcs->hex == NULL)
 731                 event->funcs->hex = trace_nop_print;
 732         if (event->funcs->binary == NULL)
 733                 event->funcs->binary = trace_nop_print;
 734
 735         key = event->type & (EVENT_HASHSIZE - 1);
 736
 737         hlist_add_head(&event->node, &event_hash[key]);
 738
 739         ret = event->type;
 740  out:
 741         up_write(&trace_event_sem);
 742
 743         return ret;
 744 }
 745 EXPORT_SYMBOL_GPL(register_trace_event);
 746
 747 /*
 748  * Used by module code with the trace_event_sem held for write.
 749  */
 750 int __unregister_trace_event(struct trace_event *event)
 751 {
 752         hlist_del(&event->node);
 753         list_del(&event->list);
 754         return 0;
 755 }
 756
 757 /**
 758  * unregister_trace_event - remove a no longer used event
 759  * @event: the event to remove
 760  */
 761 int unregister_trace_event(struct trace_event *event)
 762 {
 763         down_write(&trace_event_sem);
 764         __unregister_trace_event(event);
 765         up_write(&trace_event_sem);
 766
 767         return 0;
 768 }
 769 EXPORT_SYMBOL_GPL(unregister_trace_event);
 770
 771 /*
 772  * Standard events
 773  */
 774
 775 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
 776                                   struct trace_event *event)
 777 {
 778         trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
 779
 780         return trace_handle_return(&iter->seq);
 781 }
 782
 783 /* TRACE_FN */
 784 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
 785                                         struct trace_event *event)
 786 {
 787         struct ftrace_entry *field;
 788         struct trace_seq *s = &iter->seq;
 789
 790         trace_assign_type(field, iter->ent);
 791
 792         seq_print_ip_sym(s, field->ip, flags);
 793
 794         if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
 795                 trace_seq_puts(s, " <-");
 796                 seq_print_ip_sym(s, field->parent_ip, flags);
 797         }
 798
 799         trace_seq_putc(s, '\n');
 800
 801         return trace_handle_return(s);
 802 }
 803
 804 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
 805                                       struct trace_event *event)
 806 {
 807         struct ftrace_entry *field;
 808
 809         trace_assign_type(field, iter->ent);
 810
 811         trace_seq_printf(&iter->seq, "%lx %lx\n",
 812                          field->ip,
 813                          field->parent_ip);
 814
 815         return trace_handle_return(&iter->seq);
 816 }
 817
 818 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
 819                                       struct trace_event *event)
 820 {
 821         struct ftrace_entry *field;
 822         struct trace_seq *s = &iter->seq;
 823
 824         trace_assign_type(field, iter->ent);
 825
 826         SEQ_PUT_HEX_FIELD(s, field->ip);
 827         SEQ_PUT_HEX_FIELD(s, field->parent_ip);
 828
 829         return trace_handle_return(s);
 830 }
 831
 832 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
 833                                       struct trace_event *event)
 834 {
 835         struct ftrace_entry *field;
 836         struct trace_seq *s = &iter->seq;
 837
 838         trace_assign_type(field, iter->ent);
 839
 840         SEQ_PUT_FIELD(s, field->ip);
 841         SEQ_PUT_FIELD(s, field->parent_ip);
 842
 843         return trace_handle_return(s);
 844 }
 845
 846 static struct trace_event_functions trace_fn_funcs = {
 847         .trace          = trace_fn_trace,
 848         .raw            = trace_fn_raw,
 849         .hex            = trace_fn_hex,
 850         .binary         = trace_fn_bin,
 851 };
 852
 853 static struct trace_event trace_fn_event = {
 854         .type           = TRACE_FN,
 855         .funcs          = &trace_fn_funcs,
 856 };
 857
 858 /* TRACE_GRAPH_ENT */
 859 static enum print_line_t trace_graph_ent_trace(struct trace_iterator *iter, int flags,
 860                                         struct trace_event *event)
 861 {
 862         struct trace_seq *s = &iter->seq;
 863         struct ftrace_graph_ent_entry *field;
 864
 865         trace_assign_type(field, iter->ent);
 866
 867         trace_seq_puts(s, "graph_ent: func=");
 868         if (trace_seq_has_overflowed(s))
 869                 return TRACE_TYPE_PARTIAL_LINE;
 870
 871         if (!seq_print_ip_sym(s, field->graph_ent.func, flags))
 872                 return TRACE_TYPE_PARTIAL_LINE;
 873
 874         trace_seq_puts(s, "\n");
 875         if (trace_seq_has_overflowed(s))
 876                 return TRACE_TYPE_PARTIAL_LINE;
 877
 878         return TRACE_TYPE_HANDLED;
 879 }
 880
 881 static enum print_line_t trace_graph_ent_raw(struct trace_iterator *iter, int flags,
 882                                       struct trace_event *event)
 883 {
 884         struct ftrace_graph_ent_entry *field;
 885
 886         trace_assign_type(field, iter->ent);
 887
 888         trace_seq_printf(&iter->seq, "%lx %d\n",
 889                               field->graph_ent.func,
 890                               field->graph_ent.depth);
 891         if (trace_seq_has_overflowed(&iter->seq))
 892                 return TRACE_TYPE_PARTIAL_LINE;
 893
 894         return TRACE_TYPE_HANDLED;
 895 }
 896
 897 static enum print_line_t trace_graph_ent_hex(struct trace_iterator *iter, int flags,
 898                                       struct trace_event *event)
 899 {
 900         struct ftrace_graph_ent_entry *field;
 901         struct trace_seq *s = &iter->seq;
 902
 903         trace_assign_type(field, iter->ent);
 904
 905         SEQ_PUT_HEX_FIELD(s, field->graph_ent.func);
 906         SEQ_PUT_HEX_FIELD(s, field->graph_ent.depth);
 907
 908         return TRACE_TYPE_HANDLED;
 909 }
 910
 911 static enum print_line_t trace_graph_ent_bin(struct trace_iterator *iter, int flags,
 912                                       struct trace_event *event)
 913 {
 914         struct ftrace_graph_ent_entry *field;
 915         struct trace_seq *s = &iter->seq;
 916
 917         trace_assign_type(field, iter->ent);
 918
 919         SEQ_PUT_FIELD(s, field->graph_ent.func);
 920         SEQ_PUT_FIELD(s, field->graph_ent.depth);
 921
 922         return TRACE_TYPE_HANDLED;
 923 }
 924
 925 static struct trace_event_functions trace_graph_ent_funcs = {
 926         .trace          = trace_graph_ent_trace,
 927         .raw            = trace_graph_ent_raw,
 928         .hex            = trace_graph_ent_hex,
 929         .binary         = trace_graph_ent_bin,
 930 };
 931
 932 static struct trace_event trace_graph_ent_event = {
 933         .type           = TRACE_GRAPH_ENT,
 934         .funcs          = &trace_graph_ent_funcs,
 935 };
 936
 937 /* TRACE_GRAPH_RET */
 938 static enum print_line_t trace_graph_ret_trace(struct trace_iterator *iter, int flags,
 939                                         struct trace_event *event)
 940 {
 941         struct trace_seq *s = &iter->seq;
 942         struct trace_entry *entry = iter->ent;
 943         struct ftrace_graph_ret_entry *field;
 944
 945         trace_assign_type(field, entry);
 946
 947         trace_seq_puts(s, "graph_ret: func=");
 948         if (trace_seq_has_overflowed(s))
 949                 return TRACE_TYPE_PARTIAL_LINE;
 950
 951         if (!seq_print_ip_sym(s, field->ret.func, flags))
 952                 return TRACE_TYPE_PARTIAL_LINE;
 953
 954         trace_seq_puts(s, "\n");
 955         if (trace_seq_has_overflowed(s))
 956                 return TRACE_TYPE_PARTIAL_LINE;
 957
 958         return TRACE_TYPE_HANDLED;
 959 }
 960
 961 static enum print_line_t trace_graph_ret_raw(struct trace_iterator *iter, int flags,
 962                                       struct trace_event *event)
 963 {
 964         struct ftrace_graph_ret_entry *field;
 965
 966         trace_assign_type(field, iter->ent);
 967
 968         trace_seq_printf(&iter->seq, "%lx %lld %lld %ld %d\n",
 969                               field->ret.func,
 970                               field->ret.calltime,
 971                               field->ret.rettime,
 972                               field->ret.overrun,
 973                               field->ret.depth);
 974         if (trace_seq_has_overflowed(&iter->seq))
 975                 return TRACE_TYPE_PARTIAL_LINE;
 976
 977         return TRACE_TYPE_HANDLED;
 978 }
 979
 980 static enum print_line_t trace_graph_ret_hex(struct trace_iterator *iter, int flags,
 981                                       struct trace_event *event)
 982 {
 983         struct ftrace_graph_ret_entry *field;
 984         struct trace_seq *s = &iter->seq;
 985
 986         trace_assign_type(field, iter->ent);
 987
 988         SEQ_PUT_HEX_FIELD(s, field->ret.func);
 989         SEQ_PUT_HEX_FIELD(s, field->ret.calltime);
 990         SEQ_PUT_HEX_FIELD(s, field->ret.rettime);
 991         SEQ_PUT_HEX_FIELD(s, field->ret.overrun);
 992         SEQ_PUT_HEX_FIELD(s, field->ret.depth);
 993
 994         return TRACE_TYPE_HANDLED;
 995 }
 996
 997 static enum print_line_t trace_graph_ret_bin(struct trace_iterator *iter, int flags,
 998                                       struct trace_event *event)
 999 {
1000         struct ftrace_graph_ret_entry *field;
1001         struct trace_seq *s = &iter->seq;
1002
1003         trace_assign_type(field, iter->ent);
1004
1005         SEQ_PUT_FIELD(s, field->ret.func);
1006         SEQ_PUT_FIELD(s, field->ret.calltime);
1007         SEQ_PUT_FIELD(s, field->ret.rettime);
1008         SEQ_PUT_FIELD(s, field->ret.overrun);
1009         SEQ_PUT_FIELD(s, field->ret.depth);
1010
1011         return TRACE_TYPE_HANDLED;
1012 }
1013
1014 static struct trace_event_functions trace_graph_ret_funcs = {
1015         .trace          = trace_graph_ret_trace,
1016         .raw            = trace_graph_ret_raw,
1017         .hex            = trace_graph_ret_hex,
1018         .binary         = trace_graph_ret_bin,
1019 };
1020
1021 static struct trace_event trace_graph_ret_event = {
1022         .type           = TRACE_GRAPH_RET,
1023         .funcs          = &trace_graph_ret_funcs,
1024 };
1025
1026 /* TRACE_CTX an TRACE_WAKE */
1027 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
1028                                              char *delim)
1029 {
1030         struct ctx_switch_entry *field;
1031         char comm[TASK_COMM_LEN];
1032         int S, T;
1033
1034
1035         trace_assign_type(field, iter->ent);
1036
1037         T = task_state_char(field->next_state);
1038         S = task_state_char(field->prev_state);
1039         trace_find_cmdline(field->next_pid, comm);
1040         trace_seq_printf(&iter->seq,
1041                          " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
1042                          field->prev_pid,
1043                          field->prev_prio,
1044                          S, delim,
1045                          field->next_cpu,
1046                          field->next_pid,
1047                          field->next_prio,
1048                          T, comm);
1049
1050         return trace_handle_return(&iter->seq);
1051 }
1052
1053 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
1054                                          struct trace_event *event)
1055 {
1056         return trace_ctxwake_print(iter, "==>");
1057 }
1058
1059 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
1060                                           int flags, struct trace_event *event)
1061 {
1062         return trace_ctxwake_print(iter, "  +");
1063 }
1064
1065 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
1066 {
1067         struct ctx_switch_entry *field;
1068         int T;
1069
1070         trace_assign_type(field, iter->ent);
1071
1072         if (!S)
1073                 S = task_state_char(field->prev_state);
1074         T = task_state_char(field->next_state);
1075         trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
1076                          field->prev_pid,
1077                          field->prev_prio,
1078                          S,
1079                          field->next_cpu,
1080                          field->next_pid,
1081                          field->next_prio,
1082                          T);
1083
1084         return trace_handle_return(&iter->seq);
1085 }
1086
1087 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
1088                                        struct trace_event *event)
1089 {
1090         return trace_ctxwake_raw(iter, 0);
1091 }
1092
1093 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
1094                                         struct trace_event *event)
1095 {
1096         return trace_ctxwake_raw(iter, '+');
1097 }
1098
1099
1100 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
1101 {
1102         struct ctx_switch_entry *field;
1103         struct trace_seq *s = &iter->seq;
1104         int T;
1105
1106         trace_assign_type(field, iter->ent);
1107
1108         if (!S)
1109                 S = task_state_char(field->prev_state);
1110         T = task_state_char(field->next_state);
1111
1112         SEQ_PUT_HEX_FIELD(s, field->prev_pid);
1113         SEQ_PUT_HEX_FIELD(s, field->prev_prio);
1114         SEQ_PUT_HEX_FIELD(s, S);
1115         SEQ_PUT_HEX_FIELD(s, field->next_cpu);
1116         SEQ_PUT_HEX_FIELD(s, field->next_pid);
1117         SEQ_PUT_HEX_FIELD(s, field->next_prio);
1118         SEQ_PUT_HEX_FIELD(s, T);
1119
1120         return trace_handle_return(s);
1121 }
1122
1123 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1124                                        struct trace_event *event)
1125 {
1126         return trace_ctxwake_hex(iter, 0);
1127 }
1128
1129 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1130                                         struct trace_event *event)
1131 {
1132         return trace_ctxwake_hex(iter, '+');
1133 }
1134
1135 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1136                                            int flags, struct trace_event *event)
1137 {
1138         struct ctx_switch_entry *field;
1139         struct trace_seq *s = &iter->seq;
1140
1141         trace_assign_type(field, iter->ent);
1142
1143         SEQ_PUT_FIELD(s, field->prev_pid);
1144         SEQ_PUT_FIELD(s, field->prev_prio);
1145         SEQ_PUT_FIELD(s, field->prev_state);
1146         SEQ_PUT_FIELD(s, field->next_cpu);
1147         SEQ_PUT_FIELD(s, field->next_pid);
1148         SEQ_PUT_FIELD(s, field->next_prio);
1149         SEQ_PUT_FIELD(s, field->next_state);
1150
1151         return trace_handle_return(s);
1152 }
1153
1154 static struct trace_event_functions trace_ctx_funcs = {
1155         .trace          = trace_ctx_print,
1156         .raw            = trace_ctx_raw,
1157         .hex            = trace_ctx_hex,
1158         .binary         = trace_ctxwake_bin,
1159 };
1160
1161 static struct trace_event trace_ctx_event = {
1162         .type           = TRACE_CTX,
1163         .funcs          = &trace_ctx_funcs,
1164 };
1165
1166 static struct trace_event_functions trace_wake_funcs = {
1167         .trace          = trace_wake_print,
1168         .raw            = trace_wake_raw,
1169         .hex            = trace_wake_hex,
1170         .binary         = trace_ctxwake_bin,
1171 };
1172
1173 static struct trace_event trace_wake_event = {
1174         .type           = TRACE_WAKE,
1175         .funcs          = &trace_wake_funcs,
1176 };
1177
1178 /* TRACE_STACK */
1179
1180 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1181                                            int flags, struct trace_event *event)
1182 {
1183         struct stack_entry *field;
1184         struct trace_seq *s = &iter->seq;
1185         unsigned long *p;
1186         unsigned long *end;
1187
1188         trace_assign_type(field, iter->ent);
1189         end = (unsigned long *)((long)iter->ent + iter->ent_size);
1190
1191         trace_seq_puts(s, "<stack trace>\n");
1192
1193         for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1194
1195                 if (trace_seq_has_overflowed(s))
1196                         break;
1197
1198                 trace_seq_puts(s, " => ");
1199                 seq_print_ip_sym(s, *p, flags);
1200                 trace_seq_putc(s, '\n');
1201         }
1202
1203         return trace_handle_return(s);
1204 }
1205
1206 static struct trace_event_functions trace_stack_funcs = {
1207         .trace          = trace_stack_print,
1208 };
1209
1210 static struct trace_event trace_stack_event = {
1211         .type           = TRACE_STACK,
1212         .funcs          = &trace_stack_funcs,
1213 };
1214
1215 /* TRACE_USER_STACK */
1216 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1217                                                 int flags, struct trace_event *event)
1218 {
1219         struct trace_array *tr = iter->tr;
1220         struct userstack_entry *field;
1221         struct trace_seq *s = &iter->seq;
1222         struct mm_struct *mm = NULL;
1223         unsigned int i;
1224
1225         trace_assign_type(field, iter->ent);
1226
1227         trace_seq_puts(s, "<user stack trace>\n");
1228
1229         if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) {
1230                 struct task_struct *task;
1231                 /*
1232                  * we do the lookup on the thread group leader,
1233                  * since individual threads might have already quit!
1234                  */
1235                 rcu_read_lock();
1236                 task = find_task_by_vpid(field->tgid);
1237                 if (task)
1238                         mm = get_task_mm(task);
1239                 rcu_read_unlock();
1240         }
1241
1242         for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
1243                 unsigned long ip = field->caller[i];
1244
1245                 if (ip == ULONG_MAX || trace_seq_has_overflowed(s))
1246                         break;
1247
1248                 trace_seq_puts(s, " => ");
1249
1250                 if (!ip) {
1251                         trace_seq_puts(s, "??");
1252                         trace_seq_putc(s, '\n');
1253                         continue;
1254                 }
1255
1256                 seq_print_user_ip(s, mm, ip, flags);
1257                 trace_seq_putc(s, '\n');
1258         }
1259
1260         if (mm)
1261                 mmput(mm);
1262
1263         return trace_handle_return(s);
1264 }
1265
1266 static struct trace_event_functions trace_user_stack_funcs = {
1267         .trace          = trace_user_stack_print,
1268 };
1269
1270 static struct trace_event trace_user_stack_event = {
1271         .type           = TRACE_USER_STACK,
1272         .funcs          = &trace_user_stack_funcs,
1273 };
1274
1275 /* TRACE_BPUTS */
1276 static enum print_line_t
1277 trace_bputs_print(struct trace_iterator *iter, int flags,
1278                    struct trace_event *event)
1279 {
1280         struct trace_entry *entry = iter->ent;
1281         struct trace_seq *s = &iter->seq;
1282         struct bputs_entry *field;
1283
1284         trace_assign_type(field, entry);
1285
1286         seq_print_ip_sym(s, field->ip, flags);
1287         trace_seq_puts(s, ": ");
1288         trace_seq_puts(s, field->str);
1289
1290         return trace_handle_return(s);
1291 }
1292
1293
1294 static enum print_line_t
1295 trace_bputs_raw(struct trace_iterator *iter, int flags,
1296                 struct trace_event *event)
1297 {
1298         struct bputs_entry *field;
1299         struct trace_seq *s = &iter->seq;
1300
1301         trace_assign_type(field, iter->ent);
1302
1303         trace_seq_printf(s, ": %lx : ", field->ip);
1304         trace_seq_puts(s, field->str);
1305
1306         return trace_handle_return(s);
1307 }
1308
1309 static struct trace_event_functions trace_bputs_funcs = {
1310         .trace          = trace_bputs_print,
1311         .raw            = trace_bputs_raw,
1312 };
1313
1314 static struct trace_event trace_bputs_event = {
1315         .type           = TRACE_BPUTS,
1316         .funcs          = &trace_bputs_funcs,
1317 };
1318
1319 /* TRACE_BPRINT */
1320 static enum print_line_t
1321 trace_bprint_print(struct trace_iterator *iter, int flags,
1322                    struct trace_event *event)
1323 {
1324         struct trace_entry *entry = iter->ent;
1325         struct trace_seq *s = &iter->seq;
1326         struct bprint_entry *field;
1327
1328         trace_assign_type(field, entry);
1329
1330         seq_print_ip_sym(s, field->ip, flags);
1331         trace_seq_puts(s, ": ");
1332         trace_seq_bprintf(s, field->fmt, field->buf);
1333
1334         return trace_handle_return(s);
1335 }
1336
1337
1338 static enum print_line_t
1339 trace_bprint_raw(struct trace_iterator *iter, int flags,
1340                  struct trace_event *event)
1341 {
1342         struct bprint_entry *field;
1343         struct trace_seq *s = &iter->seq;
1344
1345         trace_assign_type(field, iter->ent);
1346
1347         trace_seq_printf(s, ": %lx : ", field->ip);
1348         trace_seq_bprintf(s, field->fmt, field->buf);
1349
1350         return trace_handle_return(s);
1351 }
1352
1353 static struct trace_event_functions trace_bprint_funcs = {
1354         .trace          = trace_bprint_print,
1355         .raw            = trace_bprint_raw,
1356 };
1357
1358 static struct trace_event trace_bprint_event = {
1359         .type           = TRACE_BPRINT,
1360         .funcs          = &trace_bprint_funcs,
1361 };
1362
1363 /* TRACE_PRINT */
1364 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1365                                            int flags, struct trace_event *event)
1366 {
1367         struct print_entry *field;
1368         struct trace_seq *s = &iter->seq;
1369
1370         trace_assign_type(field, iter->ent);
1371
1372         seq_print_ip_sym(s, field->ip, flags);
1373         trace_seq_printf(s, ": %s", field->buf);
1374
1375         return trace_handle_return(s);
1376 }
1377
1378 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1379                                          struct trace_event *event)
1380 {
1381         struct print_entry *field;
1382
1383         trace_assign_type(field, iter->ent);
1384
1385         trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
1386
1387         return trace_handle_return(&iter->seq);
1388 }
1389
1390 static struct trace_event_functions trace_print_funcs = {
1391         .trace          = trace_print_print,
1392         .raw            = trace_print_raw,
1393 };
1394
1395 static struct trace_event trace_print_event = {
1396         .type           = TRACE_PRINT,
1397         .funcs          = &trace_print_funcs,
1398 };
1399
1400
1401 static struct trace_event *events[] __initdata = {
1402         &trace_fn_event,
1403         &trace_graph_ent_event,
1404         &trace_graph_ret_event,
1405         &trace_ctx_event,
1406         &trace_wake_event,
1407         &trace_stack_event,
1408         &trace_user_stack_event,
1409         &trace_bputs_event,
1410         &trace_bprint_event,
1411         &trace_print_event,
1412         NULL
1413 };
1414
1415 __init static int init_events(void)
1416 {
1417         struct trace_event *event;
1418         int i, ret;
1419
1420         for (i = 0; events[i]; i++) {
1421                 event = events[i];
1422
1423                 ret = register_trace_event(event);
1424                 if (!ret) {
1425                         printk(KERN_WARNING "event %d failed to register\n",
1426                                event->type);
1427                         WARN_ON_ONCE(1);
1428                 }
1429         }
1430
1431         return 0;
1432 }
1433 early_initcall(init_events);