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 ftrace_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(ftrace_print_flags_seq);
  99
 100 const char *
 101 ftrace_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(ftrace_print_symbols_seq);
 124
 125 #if BITS_PER_LONG == 32
 126 const char *
 127 ftrace_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(ftrace_print_symbols_seq_u64);
 150 #endif
 151
 152 const char *
 153 ftrace_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(ftrace_print_bitmask_seq);
 164
 165 const char *
 166 ftrace_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(ftrace_print_hex_seq);
 179
 180 const char *
 181 ftrace_print_array_seq(struct trace_seq *p, const void *buf, int buf_len,
 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
 188         trace_seq_putc(p, '{');
 189
 190         while (ptr < buf + buf_len) {
 191                 switch (el_size) {
 192                 case 1:
 193                         trace_seq_printf(p, "%s0x%x", prefix,
 194                                          *(u8 *)ptr);
 195                         break;
 196                 case 2:
 197                         trace_seq_printf(p, "%s0x%x", prefix,
 198                                          *(u16 *)ptr);
 199                         break;
 200                 case 4:
 201                         trace_seq_printf(p, "%s0x%x", prefix,
 202                                          *(u32 *)ptr);
 203                         break;
 204                 case 8:
 205                         trace_seq_printf(p, "%s0x%llx", prefix,
 206                                          *(u64 *)ptr);
 207                         break;
 208                 default:
 209                         trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size,
 210                                          *(u8 *)ptr);
 211                         el_size = 1;
 212                 }
 213                 prefix = ",";
 214                 ptr += el_size;
 215         }
 216
 217         trace_seq_putc(p, '}');
 218         trace_seq_putc(p, 0);
 219
 220         return ret;
 221 }
 222 EXPORT_SYMBOL(ftrace_print_array_seq);
 223
 224 int ftrace_raw_output_prep(struct trace_iterator *iter,
 225                            struct trace_event *trace_event)
 226 {
 227         struct ftrace_event_call *event;
 228         struct trace_seq *s = &iter->seq;
 229         struct trace_seq *p = &iter->tmp_seq;
 230         struct trace_entry *entry;
 231
 232         event = container_of(trace_event, struct ftrace_event_call, event);
 233         entry = iter->ent;
 234
 235         if (entry->type != event->event.type) {
 236                 WARN_ON_ONCE(1);
 237                 return TRACE_TYPE_UNHANDLED;
 238         }
 239
 240         trace_seq_init(p);
 241         trace_seq_printf(s, "%s: ", ftrace_event_name(event));
 242
 243         return trace_handle_return(s);
 244 }
 245 EXPORT_SYMBOL(ftrace_raw_output_prep);
 246
 247 static int ftrace_output_raw(struct trace_iterator *iter, char *name,
 248                              char *fmt, va_list ap)
 249 {
 250         struct trace_seq *s = &iter->seq;
 251
 252         trace_seq_printf(s, "%s: ", name);
 253         trace_seq_vprintf(s, fmt, ap);
 254
 255         return trace_handle_return(s);
 256 }
 257
 258 int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
 259 {
 260         va_list ap;
 261         int ret;
 262
 263         va_start(ap, fmt);
 264         ret = ftrace_output_raw(iter, name, fmt, ap);
 265         va_end(ap);
 266
 267         return ret;
 268 }
 269 EXPORT_SYMBOL_GPL(ftrace_output_call);
 270
 271 #ifdef CONFIG_KRETPROBES
 272 static inline const char *kretprobed(const char *name)
 273 {
 274         static const char tramp_name[] = "kretprobe_trampoline";
 275         int size = sizeof(tramp_name);
 276
 277         if (strncmp(tramp_name, name, size) == 0)
 278                 return "[unknown/kretprobe'd]";
 279         return name;
 280 }
 281 #else
 282 static inline const char *kretprobed(const char *name)
 283 {
 284         return name;
 285 }
 286 #endif /* CONFIG_KRETPROBES */
 287
 288 static void
 289 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
 290 {
 291 #ifdef CONFIG_KALLSYMS
 292         char str[KSYM_SYMBOL_LEN];
 293         const char *name;
 294
 295         kallsyms_lookup(address, NULL, NULL, NULL, str);
 296
 297         name = kretprobed(str);
 298
 299         trace_seq_printf(s, fmt, name);
 300 #endif
 301 }
 302
 303 static void
 304 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
 305                      unsigned long address)
 306 {
 307 #ifdef CONFIG_KALLSYMS
 308         char str[KSYM_SYMBOL_LEN];
 309         const char *name;
 310
 311         sprint_symbol(str, address);
 312         name = kretprobed(str);
 313
 314         trace_seq_printf(s, fmt, name);
 315 #endif
 316 }
 317
 318 #ifndef CONFIG_64BIT
 319 # define IP_FMT "%08lx"
 320 #else
 321 # define IP_FMT "%016lx"
 322 #endif
 323
 324 int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
 325                       unsigned long ip, unsigned long sym_flags)
 326 {
 327         struct file *file = NULL;
 328         unsigned long vmstart = 0;
 329         int ret = 1;
 330
 331         if (s->full)
 332                 return 0;
 333
 334         if (mm) {
 335                 const struct vm_area_struct *vma;
 336
 337                 down_read(&mm->mmap_sem);
 338                 vma = find_vma(mm, ip);
 339                 if (vma) {
 340                         file = vma->vm_file;
 341                         vmstart = vma->vm_start;
 342                 }
 343                 if (file) {
 344                         ret = trace_seq_path(s, &file->f_path);
 345                         if (ret)
 346                                 trace_seq_printf(s, "[+0x%lx]",
 347                                                  ip - vmstart);
 348                 }
 349                 up_read(&mm->mmap_sem);
 350         }
 351         if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
 352                 trace_seq_printf(s, " <" IP_FMT ">", ip);
 353         return !trace_seq_has_overflowed(s);
 354 }
 355
 356 int
 357 seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
 358                       unsigned long sym_flags)
 359 {
 360         struct mm_struct *mm = NULL;
 361         unsigned int i;
 362
 363         if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
 364                 struct task_struct *task;
 365                 /*
 366                  * we do the lookup on the thread group leader,
 367                  * since individual threads might have already quit!
 368                  */
 369                 rcu_read_lock();
 370                 task = find_task_by_vpid(entry->tgid);
 371                 if (task)
 372                         mm = get_task_mm(task);
 373                 rcu_read_unlock();
 374         }
 375
 376         for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
 377                 unsigned long ip = entry->caller[i];
 378
 379                 if (ip == ULONG_MAX || trace_seq_has_overflowed(s))
 380                         break;
 381
 382                 trace_seq_puts(s, " => ");
 383
 384                 if (!ip) {
 385                         trace_seq_puts(s, "??");
 386                         trace_seq_putc(s, '\n');
 387                         continue;
 388                 }
 389
 390                 seq_print_user_ip(s, mm, ip, sym_flags);
 391                 trace_seq_putc(s, '\n');
 392         }
 393
 394         if (mm)
 395                 mmput(mm);
 396
 397         return !trace_seq_has_overflowed(s);
 398 }
 399
 400 int
 401 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 402 {
 403         if (!ip) {
 404                 trace_seq_putc(s, '0');
 405                 goto out;
 406         }
 407
 408         if (sym_flags & TRACE_ITER_SYM_OFFSET)
 409                 seq_print_sym_offset(s, "%s", ip);
 410         else
 411                 seq_print_sym_short(s, "%s", ip);
 412
 413         if (sym_flags & TRACE_ITER_SYM_ADDR)
 414                 trace_seq_printf(s, " <" IP_FMT ">", ip);
 415
 416  out:
 417         return !trace_seq_has_overflowed(s);
 418 }
 419
 420 /**
 421  * trace_print_lat_fmt - print the irq, preempt and lockdep fields
 422  * @s: trace seq struct to write to
 423  * @entry: The trace entry field from the ring buffer
 424  *
 425  * Prints the generic fields of irqs off, in hard or softirq, preempt
 426  * count.
 427  */
 428 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 429 {
 430         char hardsoft_irq;
 431         char need_resched;
 432         char irqs_off;
 433         int hardirq;
 434         int softirq;
 435
 436         hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 437         softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 438
 439         irqs_off =
 440                 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 441                 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 442                 '.';
 443
 444         switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
 445                                 TRACE_FLAG_PREEMPT_RESCHED)) {
 446         case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 447                 need_resched = 'N';
 448                 break;
 449         case TRACE_FLAG_NEED_RESCHED:
 450                 need_resched = 'n';
 451                 break;
 452         case TRACE_FLAG_PREEMPT_RESCHED:
 453                 need_resched = 'p';
 454                 break;
 455         default:
 456                 need_resched = '.';
 457                 break;
 458         }
 459
 460         hardsoft_irq =
 461                 (hardirq && softirq) ? 'H' :
 462                 hardirq ? 'h' :
 463                 softirq ? 's' :
 464                 '.';
 465
 466         trace_seq_printf(s, "%c%c%c",
 467                          irqs_off, need_resched, hardsoft_irq);
 468
 469         if (entry->preempt_count)
 470                 trace_seq_printf(s, "%x", entry->preempt_count);
 471         else
 472                 trace_seq_putc(s, '.');
 473
 474         return !trace_seq_has_overflowed(s);
 475 }
 476
 477 static int
 478 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 479 {
 480         char comm[TASK_COMM_LEN];
 481
 482         trace_find_cmdline(entry->pid, comm);
 483
 484         trace_seq_printf(s, "%8.8s-%-5d %3d",
 485                          comm, entry->pid, cpu);
 486
 487         return trace_print_lat_fmt(s, entry);
 488 }
 489
 490 #undef MARK
 491 #define MARK(v, s) {.val = v, .sym = s}
 492 /* trace overhead mark */
 493 static const struct trace_mark {
 494         unsigned long long      val; /* unit: nsec */
 495         char                    sym;
 496 } mark[] = {
 497         MARK(1000000000ULL      , '$'), /* 1 sec */
 498         MARK(1000000ULL         , '#'), /* 1000 usecs */
 499         MARK(100000ULL          , '!'), /* 100 usecs */
 500         MARK(10000ULL           , '+'), /* 10 usecs */
 501 };
 502 #undef MARK
 503
 504 char trace_find_mark(unsigned long long d)
 505 {
 506         int i;
 507         int size = ARRAY_SIZE(mark);
 508
 509         for (i = 0; i < size; i++) {
 510                 if (d >= mark[i].val)
 511                         break;
 512         }
 513
 514         return (i == size) ? ' ' : mark[i].sym;
 515 }
 516
 517 static int
 518 lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
 519 {
 520         unsigned long verbose = trace_flags & TRACE_ITER_VERBOSE;
 521         unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
 522         unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start;
 523         unsigned long long rel_ts = next_ts - iter->ts;
 524         struct trace_seq *s = &iter->seq;
 525
 526         if (in_ns) {
 527                 abs_ts = ns2usecs(abs_ts);
 528                 rel_ts = ns2usecs(rel_ts);
 529         }
 530
 531         if (verbose && in_ns) {
 532                 unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
 533                 unsigned long abs_msec = (unsigned long)abs_ts;
 534                 unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
 535                 unsigned long rel_msec = (unsigned long)rel_ts;
 536
 537                 trace_seq_printf(
 538                         s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
 539                         ns2usecs(iter->ts),
 540                         abs_msec, abs_usec,
 541                         rel_msec, rel_usec);
 542
 543         } else if (verbose && !in_ns) {
 544                 trace_seq_printf(
 545                         s, "[%016llx] %lld (+%lld): ",
 546                         iter->ts, abs_ts, rel_ts);
 547
 548         } else if (!verbose && in_ns) {
 549                 trace_seq_printf(
 550                         s, " %4lldus%c: ",
 551                         abs_ts,
 552                         trace_find_mark(rel_ts * NSEC_PER_USEC));
 553
 554         } else { /* !verbose && !in_ns */
 555                 trace_seq_printf(s, " %4lld: ", abs_ts);
 556         }
 557
 558         return !trace_seq_has_overflowed(s);
 559 }
 560
 561 int trace_print_context(struct trace_iterator *iter)
 562 {
 563         struct trace_seq *s = &iter->seq;
 564         struct trace_entry *entry = iter->ent;
 565         unsigned long long t;
 566         unsigned long secs, usec_rem;
 567         char comm[TASK_COMM_LEN];
 568
 569         trace_find_cmdline(entry->pid, comm);
 570
 571         trace_seq_printf(s, "%16s-%-5d [%03d] ",
 572                                comm, entry->pid, iter->cpu);
 573
 574         if (trace_flags & TRACE_ITER_IRQ_INFO)
 575                 trace_print_lat_fmt(s, entry);
 576
 577         if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
 578                 t = ns2usecs(iter->ts);
 579                 usec_rem = do_div(t, USEC_PER_SEC);
 580                 secs = (unsigned long)t;
 581                 trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
 582         } else
 583                 trace_seq_printf(s, " %12llu: ", iter->ts);
 584
 585         return !trace_seq_has_overflowed(s);
 586 }
 587
 588 int trace_print_lat_context(struct trace_iterator *iter)
 589 {
 590         u64 next_ts;
 591         /* trace_find_next_entry will reset ent_size */
 592         int ent_size = iter->ent_size;
 593         struct trace_seq *s = &iter->seq;
 594         struct trace_entry *entry = iter->ent,
 595                            *next_entry = trace_find_next_entry(iter, NULL,
 596                                                                &next_ts);
 597         unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
 598
 599         /* Restore the original ent_size */
 600         iter->ent_size = ent_size;
 601
 602         if (!next_entry)
 603                 next_ts = iter->ts;
 604
 605         if (verbose) {
 606                 char comm[TASK_COMM_LEN];
 607
 608                 trace_find_cmdline(entry->pid, comm);
 609
 610                 trace_seq_printf(
 611                         s, "%16s %5d %3d %d %08x %08lx ",
 612                         comm, entry->pid, iter->cpu, entry->flags,
 613                         entry->preempt_count, iter->idx);
 614         } else {
 615                 lat_print_generic(s, entry, iter->cpu);
 616         }
 617
 618         lat_print_timestamp(iter, next_ts);
 619
 620         return !trace_seq_has_overflowed(s);
 621 }
 622
 623 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
 624
 625 static int task_state_char(unsigned long state)
 626 {
 627         int bit = state ? __ffs(state) + 1 : 0;
 628
 629         return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
 630 }
 631
 632 /**
 633  * ftrace_find_event - find a registered event
 634  * @type: the type of event to look for
 635  *
 636  * Returns an event of type @type otherwise NULL
 637  * Called with trace_event_read_lock() held.
 638  */
 639 struct trace_event *ftrace_find_event(int type)
 640 {
 641         struct trace_event *event;
 642         unsigned key;
 643
 644         key = type & (EVENT_HASHSIZE - 1);
 645
 646         hlist_for_each_entry(event, &event_hash[key], node) {
 647                 if (event->type == type)
 648                         return event;
 649         }
 650
 651         return NULL;
 652 }
 653
 654 static LIST_HEAD(ftrace_event_list);
 655
 656 static int trace_search_list(struct list_head **list)
 657 {
 658         struct trace_event *e;
 659         int last = __TRACE_LAST_TYPE;
 660
 661         if (list_empty(&ftrace_event_list)) {
 662                 *list = &ftrace_event_list;
 663                 return last + 1;
 664         }
 665
 666         /*
 667          * We used up all possible max events,
 668          * lets see if somebody freed one.
 669          */
 670         list_for_each_entry(e, &ftrace_event_list, list) {
 671                 if (e->type != last + 1)
 672                         break;
 673                 last++;
 674         }
 675
 676         /* Did we used up all 65 thousand events??? */
 677         if ((last + 1) > FTRACE_MAX_EVENT)
 678                 return 0;
 679
 680         *list = &e->list;
 681         return last + 1;
 682 }
 683
 684 void trace_event_read_lock(void)
 685 {
 686         down_read(&trace_event_sem);
 687 }
 688
 689 void trace_event_read_unlock(void)
 690 {
 691         up_read(&trace_event_sem);
 692 }
 693
 694 /**
 695  * register_ftrace_event - register output for an event type
 696  * @event: the event type to register
 697  *
 698  * Event types are stored in a hash and this hash is used to
 699  * find a way to print an event. If the @event->type is set
 700  * then it will use that type, otherwise it will assign a
 701  * type to use.
 702  *
 703  * If you assign your own type, please make sure it is added
 704  * to the trace_type enum in trace.h, to avoid collisions
 705  * with the dynamic types.
 706  *
 707  * Returns the event type number or zero on error.
 708  */
 709 int register_ftrace_event(struct trace_event *event)
 710 {
 711         unsigned key;
 712         int ret = 0;
 713
 714         down_write(&trace_event_sem);
 715
 716         if (WARN_ON(!event))
 717                 goto out;
 718
 719         if (WARN_ON(!event->funcs))
 720                 goto out;
 721
 722         INIT_LIST_HEAD(&event->list);
 723
 724         if (!event->type) {
 725                 struct list_head *list = NULL;
 726
 727                 if (next_event_type > FTRACE_MAX_EVENT) {
 728
 729                         event->type = trace_search_list(&list);
 730                         if (!event->type)
 731                                 goto out;
 732
 733                 } else {
 734
 735                         event->type = next_event_type++;
 736                         list = &ftrace_event_list;
 737                 }
 738
 739                 if (WARN_ON(ftrace_find_event(event->type)))
 740                         goto out;
 741
 742                 list_add_tail(&event->list, list);
 743
 744         } else if (event->type > __TRACE_LAST_TYPE) {
 745                 printk(KERN_WARNING "Need to add type to trace.h\n");
 746                 WARN_ON(1);
 747                 goto out;
 748         } else {
 749                 /* Is this event already used */
 750                 if (ftrace_find_event(event->type))
 751                         goto out;
 752         }
 753
 754         if (event->funcs->trace == NULL)
 755                 event->funcs->trace = trace_nop_print;
 756         if (event->funcs->raw == NULL)
 757                 event->funcs->raw = trace_nop_print;
 758         if (event->funcs->hex == NULL)
 759                 event->funcs->hex = trace_nop_print;
 760         if (event->funcs->binary == NULL)
 761                 event->funcs->binary = trace_nop_print;
 762
 763         key = event->type & (EVENT_HASHSIZE - 1);
 764
 765         hlist_add_head(&event->node, &event_hash[key]);
 766
 767         ret = event->type;
 768  out:
 769         up_write(&trace_event_sem);
 770
 771         return ret;
 772 }
 773 EXPORT_SYMBOL_GPL(register_ftrace_event);
 774
 775 /*
 776  * Used by module code with the trace_event_sem held for write.
 777  */
 778 int __unregister_ftrace_event(struct trace_event *event)
 779 {
 780         hlist_del(&event->node);
 781         list_del(&event->list);
 782         return 0;
 783 }
 784
 785 /**
 786  * unregister_ftrace_event - remove a no longer used event
 787  * @event: the event to remove
 788  */
 789 int unregister_ftrace_event(struct trace_event *event)
 790 {
 791         down_write(&trace_event_sem);
 792         __unregister_ftrace_event(event);
 793         up_write(&trace_event_sem);
 794
 795         return 0;
 796 }
 797 EXPORT_SYMBOL_GPL(unregister_ftrace_event);
 798
 799 /*
 800  * Standard events
 801  */
 802
 803 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
 804                                   struct trace_event *event)
 805 {
 806         trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
 807
 808         return trace_handle_return(&iter->seq);
 809 }
 810
 811 /* TRACE_FN */
 812 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
 813                                         struct trace_event *event)
 814 {
 815         struct ftrace_entry *field;
 816         struct trace_seq *s = &iter->seq;
 817
 818         trace_assign_type(field, iter->ent);
 819
 820         seq_print_ip_sym(s, field->ip, flags);
 821
 822         if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
 823                 trace_seq_puts(s, " <-");
 824                 seq_print_ip_sym(s, field->parent_ip, flags);
 825         }
 826
 827         trace_seq_putc(s, '\n');
 828
 829         return trace_handle_return(s);
 830 }
 831
 832 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
 833                                       struct trace_event *event)
 834 {
 835         struct ftrace_entry *field;
 836
 837         trace_assign_type(field, iter->ent);
 838
 839         trace_seq_printf(&iter->seq, "%lx %lx\n",
 840                          field->ip,
 841                          field->parent_ip);
 842
 843         return trace_handle_return(&iter->seq);
 844 }
 845
 846 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
 847                                       struct trace_event *event)
 848 {
 849         struct ftrace_entry *field;
 850         struct trace_seq *s = &iter->seq;
 851
 852         trace_assign_type(field, iter->ent);
 853
 854         SEQ_PUT_HEX_FIELD(s, field->ip);
 855         SEQ_PUT_HEX_FIELD(s, field->parent_ip);
 856
 857         return trace_handle_return(s);
 858 }
 859
 860 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
 861                                       struct trace_event *event)
 862 {
 863         struct ftrace_entry *field;
 864         struct trace_seq *s = &iter->seq;
 865
 866         trace_assign_type(field, iter->ent);
 867
 868         SEQ_PUT_FIELD(s, field->ip);
 869         SEQ_PUT_FIELD(s, field->parent_ip);
 870
 871         return trace_handle_return(s);
 872 }
 873
 874 static struct trace_event_functions trace_fn_funcs = {
 875         .trace          = trace_fn_trace,
 876         .raw            = trace_fn_raw,
 877         .hex            = trace_fn_hex,
 878         .binary         = trace_fn_bin,
 879 };
 880
 881 static struct trace_event trace_fn_event = {
 882         .type           = TRACE_FN,
 883         .funcs          = &trace_fn_funcs,
 884 };
 885
 886 /* TRACE_CTX an TRACE_WAKE */
 887 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
 888                                              char *delim)
 889 {
 890         struct ctx_switch_entry *field;
 891         char comm[TASK_COMM_LEN];
 892         int S, T;
 893
 894
 895         trace_assign_type(field, iter->ent);
 896
 897         T = task_state_char(field->next_state);
 898         S = task_state_char(field->prev_state);
 899         trace_find_cmdline(field->next_pid, comm);
 900         trace_seq_printf(&iter->seq,
 901                          " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
 902                          field->prev_pid,
 903                          field->prev_prio,
 904                          S, delim,
 905                          field->next_cpu,
 906                          field->next_pid,
 907                          field->next_prio,
 908                          T, comm);
 909
 910         return trace_handle_return(&iter->seq);
 911 }
 912
 913 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
 914                                          struct trace_event *event)
 915 {
 916         return trace_ctxwake_print(iter, "==>");
 917 }
 918
 919 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
 920                                           int flags, struct trace_event *event)
 921 {
 922         return trace_ctxwake_print(iter, "  +");
 923 }
 924
 925 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
 926 {
 927         struct ctx_switch_entry *field;
 928         int T;
 929
 930         trace_assign_type(field, iter->ent);
 931
 932         if (!S)
 933                 S = task_state_char(field->prev_state);
 934         T = task_state_char(field->next_state);
 935         trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
 936                          field->prev_pid,
 937                          field->prev_prio,
 938                          S,
 939                          field->next_cpu,
 940                          field->next_pid,
 941                          field->next_prio,
 942                          T);
 943
 944         return trace_handle_return(&iter->seq);
 945 }
 946
 947 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
 948                                        struct trace_event *event)
 949 {
 950         return trace_ctxwake_raw(iter, 0);
 951 }
 952
 953 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
 954                                         struct trace_event *event)
 955 {
 956         return trace_ctxwake_raw(iter, '+');
 957 }
 958
 959
 960 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
 961 {
 962         struct ctx_switch_entry *field;
 963         struct trace_seq *s = &iter->seq;
 964         int T;
 965
 966         trace_assign_type(field, iter->ent);
 967
 968         if (!S)
 969                 S = task_state_char(field->prev_state);
 970         T = task_state_char(field->next_state);
 971
 972         SEQ_PUT_HEX_FIELD(s, field->prev_pid);
 973         SEQ_PUT_HEX_FIELD(s, field->prev_prio);
 974         SEQ_PUT_HEX_FIELD(s, S);
 975         SEQ_PUT_HEX_FIELD(s, field->next_cpu);
 976         SEQ_PUT_HEX_FIELD(s, field->next_pid);
 977         SEQ_PUT_HEX_FIELD(s, field->next_prio);
 978         SEQ_PUT_HEX_FIELD(s, T);
 979
 980         return trace_handle_return(s);
 981 }
 982
 983 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
 984                                        struct trace_event *event)
 985 {
 986         return trace_ctxwake_hex(iter, 0);
 987 }
 988
 989 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
 990                                         struct trace_event *event)
 991 {
 992         return trace_ctxwake_hex(iter, '+');
 993 }
 994
 995 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
 996                                            int flags, struct trace_event *event)
 997 {
 998         struct ctx_switch_entry *field;
 999         struct trace_seq *s = &iter->seq;
1000
1001         trace_assign_type(field, iter->ent);
1002
1003         SEQ_PUT_FIELD(s, field->prev_pid);
1004         SEQ_PUT_FIELD(s, field->prev_prio);
1005         SEQ_PUT_FIELD(s, field->prev_state);
1006         SEQ_PUT_FIELD(s, field->next_cpu);
1007         SEQ_PUT_FIELD(s, field->next_pid);
1008         SEQ_PUT_FIELD(s, field->next_prio);
1009         SEQ_PUT_FIELD(s, field->next_state);
1010
1011         return trace_handle_return(s);
1012 }
1013
1014 static struct trace_event_functions trace_ctx_funcs = {
1015         .trace          = trace_ctx_print,
1016         .raw            = trace_ctx_raw,
1017         .hex            = trace_ctx_hex,
1018         .binary         = trace_ctxwake_bin,
1019 };
1020
1021 static struct trace_event trace_ctx_event = {
1022         .type           = TRACE_CTX,
1023         .funcs          = &trace_ctx_funcs,
1024 };
1025
1026 static struct trace_event_functions trace_wake_funcs = {
1027         .trace          = trace_wake_print,
1028         .raw            = trace_wake_raw,
1029         .hex            = trace_wake_hex,
1030         .binary         = trace_ctxwake_bin,
1031 };
1032
1033 static struct trace_event trace_wake_event = {
1034         .type           = TRACE_WAKE,
1035         .funcs          = &trace_wake_funcs,
1036 };
1037
1038 /* TRACE_STACK */
1039
1040 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1041                                            int flags, struct trace_event *event)
1042 {
1043         struct stack_entry *field;
1044         struct trace_seq *s = &iter->seq;
1045         unsigned long *p;
1046         unsigned long *end;
1047
1048         trace_assign_type(field, iter->ent);
1049         end = (unsigned long *)((long)iter->ent + iter->ent_size);
1050
1051         trace_seq_puts(s, "<stack trace>\n");
1052
1053         for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1054
1055                 if (trace_seq_has_overflowed(s))
1056                         break;
1057
1058                 trace_seq_puts(s, " => ");
1059                 seq_print_ip_sym(s, *p, flags);
1060                 trace_seq_putc(s, '\n');
1061         }
1062
1063         return trace_handle_return(s);
1064 }
1065
1066 static struct trace_event_functions trace_stack_funcs = {
1067         .trace          = trace_stack_print,
1068 };
1069
1070 static struct trace_event trace_stack_event = {
1071         .type           = TRACE_STACK,
1072         .funcs          = &trace_stack_funcs,
1073 };
1074
1075 /* TRACE_USER_STACK */
1076 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1077                                                 int flags, struct trace_event *event)
1078 {
1079         struct userstack_entry *field;
1080         struct trace_seq *s = &iter->seq;
1081
1082         trace_assign_type(field, iter->ent);
1083
1084         trace_seq_puts(s, "<user stack trace>\n");
1085         seq_print_userip_objs(field, s, flags);
1086
1087         return trace_handle_return(s);
1088 }
1089
1090 static struct trace_event_functions trace_user_stack_funcs = {
1091         .trace          = trace_user_stack_print,
1092 };
1093
1094 static struct trace_event trace_user_stack_event = {
1095         .type           = TRACE_USER_STACK,
1096         .funcs          = &trace_user_stack_funcs,
1097 };
1098
1099 /* TRACE_BPUTS */
1100 static enum print_line_t
1101 trace_bputs_print(struct trace_iterator *iter, int flags,
1102                    struct trace_event *event)
1103 {
1104         struct trace_entry *entry = iter->ent;
1105         struct trace_seq *s = &iter->seq;
1106         struct bputs_entry *field;
1107
1108         trace_assign_type(field, entry);
1109
1110         seq_print_ip_sym(s, field->ip, flags);
1111         trace_seq_puts(s, ": ");
1112         trace_seq_puts(s, field->str);
1113
1114         return trace_handle_return(s);
1115 }
1116
1117
1118 static enum print_line_t
1119 trace_bputs_raw(struct trace_iterator *iter, int flags,
1120                 struct trace_event *event)
1121 {
1122         struct bputs_entry *field;
1123         struct trace_seq *s = &iter->seq;
1124
1125         trace_assign_type(field, iter->ent);
1126
1127         trace_seq_printf(s, ": %lx : ", field->ip);
1128         trace_seq_puts(s, field->str);
1129
1130         return trace_handle_return(s);
1131 }
1132
1133 static struct trace_event_functions trace_bputs_funcs = {
1134         .trace          = trace_bputs_print,
1135         .raw            = trace_bputs_raw,
1136 };
1137
1138 static struct trace_event trace_bputs_event = {
1139         .type           = TRACE_BPUTS,
1140         .funcs          = &trace_bputs_funcs,
1141 };
1142
1143 /* TRACE_BPRINT */
1144 static enum print_line_t
1145 trace_bprint_print(struct trace_iterator *iter, int flags,
1146                    struct trace_event *event)
1147 {
1148         struct trace_entry *entry = iter->ent;
1149         struct trace_seq *s = &iter->seq;
1150         struct bprint_entry *field;
1151
1152         trace_assign_type(field, entry);
1153
1154         seq_print_ip_sym(s, field->ip, flags);
1155         trace_seq_puts(s, ": ");
1156         trace_seq_bprintf(s, field->fmt, field->buf);
1157
1158         return trace_handle_return(s);
1159 }
1160
1161
1162 static enum print_line_t
1163 trace_bprint_raw(struct trace_iterator *iter, int flags,
1164                  struct trace_event *event)
1165 {
1166         struct bprint_entry *field;
1167         struct trace_seq *s = &iter->seq;
1168
1169         trace_assign_type(field, iter->ent);
1170
1171         trace_seq_printf(s, ": %lx : ", field->ip);
1172         trace_seq_bprintf(s, field->fmt, field->buf);
1173
1174         return trace_handle_return(s);
1175 }
1176
1177 static struct trace_event_functions trace_bprint_funcs = {
1178         .trace          = trace_bprint_print,
1179         .raw            = trace_bprint_raw,
1180 };
1181
1182 static struct trace_event trace_bprint_event = {
1183         .type           = TRACE_BPRINT,
1184         .funcs          = &trace_bprint_funcs,
1185 };
1186
1187 /* TRACE_PRINT */
1188 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1189                                            int flags, struct trace_event *event)
1190 {
1191         struct print_entry *field;
1192         struct trace_seq *s = &iter->seq;
1193
1194         trace_assign_type(field, iter->ent);
1195
1196         seq_print_ip_sym(s, field->ip, flags);
1197         trace_seq_printf(s, ": %s", field->buf);
1198
1199         return trace_handle_return(s);
1200 }
1201
1202 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1203                                          struct trace_event *event)
1204 {
1205         struct print_entry *field;
1206
1207         trace_assign_type(field, iter->ent);
1208
1209         trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
1210
1211         return trace_handle_return(&iter->seq);
1212 }
1213
1214 static struct trace_event_functions trace_print_funcs = {
1215         .trace          = trace_print_print,
1216         .raw            = trace_print_raw,
1217 };
1218
1219 static struct trace_event trace_print_event = {
1220         .type           = TRACE_PRINT,
1221         .funcs          = &trace_print_funcs,
1222 };
1223
1224
1225 static struct trace_event *events[] __initdata = {
1226         &trace_fn_event,
1227         &trace_ctx_event,
1228         &trace_wake_event,
1229         &trace_stack_event,
1230         &trace_user_stack_event,
1231         &trace_bputs_event,
1232         &trace_bprint_event,
1233         &trace_print_event,
1234         NULL
1235 };
1236
1237 __init static int init_events(void)
1238 {
1239         struct trace_event *event;
1240         int i, ret;
1241
1242         for (i = 0; events[i]; i++) {
1243                 event = events[i];
1244
1245                 ret = register_ftrace_event(event);
1246                 if (!ret) {
1247                         printk(KERN_WARNING "event %d failed to register\n",
1248                                event->type);
1249                         WARN_ON_ONCE(1);
1250                 }
1251         }
1252
1253         return 0;
1254 }
1255 early_initcall(init_events);