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 int ftrace_raw_output_prep(struct trace_iterator *iter,
 181                            struct trace_event *trace_event)
 182 {
 183         struct ftrace_event_call *event;
 184         struct trace_seq *s = &iter->seq;
 185         struct trace_seq *p = &iter->tmp_seq;
 186         struct trace_entry *entry;
 187
 188         event = container_of(trace_event, struct ftrace_event_call, event);
 189         entry = iter->ent;
 190
 191         if (entry->type != event->event.type) {
 192                 WARN_ON_ONCE(1);
 193                 return TRACE_TYPE_UNHANDLED;
 194         }
 195
 196         trace_seq_init(p);
 197         trace_seq_printf(s, "%s: ", ftrace_event_name(event));
 198
 199         return trace_handle_return(s);
 200 }
 201 EXPORT_SYMBOL(ftrace_raw_output_prep);
 202
 203 static int ftrace_output_raw(struct trace_iterator *iter, char *name,
 204                              char *fmt, va_list ap)
 205 {
 206         struct trace_seq *s = &iter->seq;
 207
 208         trace_seq_printf(s, "%s: ", name);
 209         trace_seq_vprintf(s, fmt, ap);
 210
 211         return trace_handle_return(s);
 212 }
 213
 214 int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
 215 {
 216         va_list ap;
 217         int ret;
 218
 219         va_start(ap, fmt);
 220         ret = ftrace_output_raw(iter, name, fmt, ap);
 221         va_end(ap);
 222
 223         return ret;
 224 }
 225 EXPORT_SYMBOL_GPL(ftrace_output_call);
 226
 227 #ifdef CONFIG_KRETPROBES
 228 static inline const char *kretprobed(const char *name)
 229 {
 230         static const char tramp_name[] = "kretprobe_trampoline";
 231         int size = sizeof(tramp_name);
 232
 233         if (strncmp(tramp_name, name, size) == 0)
 234                 return "[unknown/kretprobe'd]";
 235         return name;
 236 }
 237 #else
 238 static inline const char *kretprobed(const char *name)
 239 {
 240         return name;
 241 }
 242 #endif /* CONFIG_KRETPROBES */
 243
 244 static void
 245 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
 246 {
 247 #ifdef CONFIG_KALLSYMS
 248         char str[KSYM_SYMBOL_LEN];
 249         const char *name;
 250
 251         kallsyms_lookup(address, NULL, NULL, NULL, str);
 252
 253         name = kretprobed(str);
 254
 255         trace_seq_printf(s, fmt, name);
 256 #endif
 257 }
 258
 259 static void
 260 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
 261                      unsigned long address)
 262 {
 263 #ifdef CONFIG_KALLSYMS
 264         char str[KSYM_SYMBOL_LEN];
 265         const char *name;
 266
 267         sprint_symbol(str, address);
 268         name = kretprobed(str);
 269
 270         trace_seq_printf(s, fmt, name);
 271 #endif
 272 }
 273
 274 #ifndef CONFIG_64BIT
 275 # define IP_FMT "%08lx"
 276 #else
 277 # define IP_FMT "%016lx"
 278 #endif
 279
 280 int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
 281                       unsigned long ip, unsigned long sym_flags)
 282 {
 283         struct file *file = NULL;
 284         unsigned long vmstart = 0;
 285         int ret = 1;
 286
 287         if (s->full)
 288                 return 0;
 289
 290         if (mm) {
 291                 const struct vm_area_struct *vma;
 292
 293                 down_read(&mm->mmap_sem);
 294                 vma = find_vma(mm, ip);
 295                 if (vma) {
 296                         file = vma->vm_file;
 297                         vmstart = vma->vm_start;
 298                 }
 299                 if (file) {
 300                         ret = trace_seq_path(s, &file->f_path);
 301                         if (ret)
 302                                 trace_seq_printf(s, "[+0x%lx]",
 303                                                  ip - vmstart);
 304                 }
 305                 up_read(&mm->mmap_sem);
 306         }
 307         if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
 308                 trace_seq_printf(s, " <" IP_FMT ">", ip);
 309         return !trace_seq_has_overflowed(s);
 310 }
 311
 312 int
 313 seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
 314                       unsigned long sym_flags)
 315 {
 316         struct mm_struct *mm = NULL;
 317         unsigned int i;
 318
 319         if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
 320                 struct task_struct *task;
 321                 /*
 322                  * we do the lookup on the thread group leader,
 323                  * since individual threads might have already quit!
 324                  */
 325                 rcu_read_lock();
 326                 task = find_task_by_vpid(entry->tgid);
 327                 if (task)
 328                         mm = get_task_mm(task);
 329                 rcu_read_unlock();
 330         }
 331
 332         for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
 333                 unsigned long ip = entry->caller[i];
 334
 335                 if (ip == ULONG_MAX || trace_seq_has_overflowed(s))
 336                         break;
 337
 338                 trace_seq_puts(s, " => ");
 339
 340                 if (!ip) {
 341                         trace_seq_puts(s, "??");
 342                         trace_seq_putc(s, '\n');
 343                         continue;
 344                 }
 345
 346                 seq_print_user_ip(s, mm, ip, sym_flags);
 347                 trace_seq_putc(s, '\n');
 348         }
 349
 350         if (mm)
 351                 mmput(mm);
 352
 353         return !trace_seq_has_overflowed(s);
 354 }
 355
 356 int
 357 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 358 {
 359         if (!ip) {
 360                 trace_seq_putc(s, '0');
 361                 goto out;
 362         }
 363
 364         if (sym_flags & TRACE_ITER_SYM_OFFSET)
 365                 seq_print_sym_offset(s, "%s", ip);
 366         else
 367                 seq_print_sym_short(s, "%s", ip);
 368
 369         if (sym_flags & TRACE_ITER_SYM_ADDR)
 370                 trace_seq_printf(s, " <" IP_FMT ">", ip);
 371
 372  out:
 373         return !trace_seq_has_overflowed(s);
 374 }
 375
 376 /**
 377  * trace_print_lat_fmt - print the irq, preempt and lockdep fields
 378  * @s: trace seq struct to write to
 379  * @entry: The trace entry field from the ring buffer
 380  *
 381  * Prints the generic fields of irqs off, in hard or softirq, preempt
 382  * count.
 383  */
 384 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 385 {
 386         char hardsoft_irq;
 387         char need_resched;
 388         char irqs_off;
 389         int hardirq;
 390         int softirq;
 391
 392         hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 393         softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 394
 395         irqs_off =
 396                 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 397                 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 398                 '.';
 399
 400         switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
 401                                 TRACE_FLAG_PREEMPT_RESCHED)) {
 402         case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 403                 need_resched = 'N';
 404                 break;
 405         case TRACE_FLAG_NEED_RESCHED:
 406                 need_resched = 'n';
 407                 break;
 408         case TRACE_FLAG_PREEMPT_RESCHED:
 409                 need_resched = 'p';
 410                 break;
 411         default:
 412                 need_resched = '.';
 413                 break;
 414         }
 415
 416         hardsoft_irq =
 417                 (hardirq && softirq) ? 'H' :
 418                 hardirq ? 'h' :
 419                 softirq ? 's' :
 420                 '.';
 421
 422         trace_seq_printf(s, "%c%c%c",
 423                          irqs_off, need_resched, hardsoft_irq);
 424
 425         if (entry->preempt_count)
 426                 trace_seq_printf(s, "%x", entry->preempt_count);
 427         else
 428                 trace_seq_putc(s, '.');
 429
 430         return !trace_seq_has_overflowed(s);
 431 }
 432
 433 static int
 434 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 435 {
 436         char comm[TASK_COMM_LEN];
 437
 438         trace_find_cmdline(entry->pid, comm);
 439
 440         trace_seq_printf(s, "%8.8s-%-5d %3d",
 441                          comm, entry->pid, cpu);
 442
 443         return trace_print_lat_fmt(s, entry);
 444 }
 445
 446 #undef MARK
 447 #define MARK(v, s) {.val = v, .sym = s}
 448 /* trace overhead mark */
 449 static const struct trace_mark {
 450         unsigned long long      val; /* unit: nsec */
 451         char                    sym;
 452 } mark[] = {
 453         MARK(1000000000ULL      , '$'), /* 1 sec */
 454         MARK(1000000ULL         , '#'), /* 1000 usecs */
 455         MARK(100000ULL          , '!'), /* 100 usecs */
 456         MARK(10000ULL           , '+'), /* 10 usecs */
 457 };
 458 #undef MARK
 459
 460 char trace_find_mark(unsigned long long d)
 461 {
 462         int i;
 463         int size = ARRAY_SIZE(mark);
 464
 465         for (i = 0; i < size; i++) {
 466                 if (d >= mark[i].val)
 467                         break;
 468         }
 469
 470         return (i == size) ? ' ' : mark[i].sym;
 471 }
 472
 473 static int
 474 lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
 475 {
 476         unsigned long verbose = trace_flags & TRACE_ITER_VERBOSE;
 477         unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
 478         unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start;
 479         unsigned long long rel_ts = next_ts - iter->ts;
 480         struct trace_seq *s = &iter->seq;
 481
 482         if (in_ns) {
 483                 abs_ts = ns2usecs(abs_ts);
 484                 rel_ts = ns2usecs(rel_ts);
 485         }
 486
 487         if (verbose && in_ns) {
 488                 unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
 489                 unsigned long abs_msec = (unsigned long)abs_ts;
 490                 unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
 491                 unsigned long rel_msec = (unsigned long)rel_ts;
 492
 493                 trace_seq_printf(
 494                         s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
 495                         ns2usecs(iter->ts),
 496                         abs_msec, abs_usec,
 497                         rel_msec, rel_usec);
 498
 499         } else if (verbose && !in_ns) {
 500                 trace_seq_printf(
 501                         s, "[%016llx] %lld (+%lld): ",
 502                         iter->ts, abs_ts, rel_ts);
 503
 504         } else if (!verbose && in_ns) {
 505                 trace_seq_printf(
 506                         s, " %4lldus%c: ",
 507                         abs_ts,
 508                         trace_find_mark(rel_ts * NSEC_PER_USEC));
 509
 510         } else { /* !verbose && !in_ns */
 511                 trace_seq_printf(s, " %4lld: ", abs_ts);
 512         }
 513
 514         return !trace_seq_has_overflowed(s);
 515 }
 516
 517 int trace_print_context(struct trace_iterator *iter)
 518 {
 519         struct trace_seq *s = &iter->seq;
 520         struct trace_entry *entry = iter->ent;
 521         unsigned long long t;
 522         unsigned long secs, usec_rem;
 523         char comm[TASK_COMM_LEN];
 524
 525         trace_find_cmdline(entry->pid, comm);
 526
 527         trace_seq_printf(s, "%16s-%-5d [%03d] ",
 528                                comm, entry->pid, iter->cpu);
 529
 530         if (trace_flags & TRACE_ITER_IRQ_INFO)
 531                 trace_print_lat_fmt(s, entry);
 532
 533         if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
 534                 t = ns2usecs(iter->ts);
 535                 usec_rem = do_div(t, USEC_PER_SEC);
 536                 secs = (unsigned long)t;
 537                 trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
 538         } else
 539                 trace_seq_printf(s, " %12llu: ", iter->ts);
 540
 541         return !trace_seq_has_overflowed(s);
 542 }
 543
 544 int trace_print_lat_context(struct trace_iterator *iter)
 545 {
 546         u64 next_ts;
 547         /* trace_find_next_entry will reset ent_size */
 548         int ent_size = iter->ent_size;
 549         struct trace_seq *s = &iter->seq;
 550         struct trace_entry *entry = iter->ent,
 551                            *next_entry = trace_find_next_entry(iter, NULL,
 552                                                                &next_ts);
 553         unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
 554
 555         /* Restore the original ent_size */
 556         iter->ent_size = ent_size;
 557
 558         if (!next_entry)
 559                 next_ts = iter->ts;
 560
 561         if (verbose) {
 562                 char comm[TASK_COMM_LEN];
 563
 564                 trace_find_cmdline(entry->pid, comm);
 565
 566                 trace_seq_printf(
 567                         s, "%16s %5d %3d %d %08x %08lx ",
 568                         comm, entry->pid, iter->cpu, entry->flags,
 569                         entry->preempt_count, iter->idx);
 570         } else {
 571                 lat_print_generic(s, entry, iter->cpu);
 572         }
 573
 574         lat_print_timestamp(iter, next_ts);
 575
 576         return !trace_seq_has_overflowed(s);
 577 }
 578
 579 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
 580
 581 static int task_state_char(unsigned long state)
 582 {
 583         int bit = state ? __ffs(state) + 1 : 0;
 584
 585         return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
 586 }
 587
 588 /**
 589  * ftrace_find_event - find a registered event
 590  * @type: the type of event to look for
 591  *
 592  * Returns an event of type @type otherwise NULL
 593  * Called with trace_event_read_lock() held.
 594  */
 595 struct trace_event *ftrace_find_event(int type)
 596 {
 597         struct trace_event *event;
 598         unsigned key;
 599
 600         key = type & (EVENT_HASHSIZE - 1);
 601
 602         hlist_for_each_entry(event, &event_hash[key], node) {
 603                 if (event->type == type)
 604                         return event;
 605         }
 606
 607         return NULL;
 608 }
 609
 610 static LIST_HEAD(ftrace_event_list);
 611
 612 static int trace_search_list(struct list_head **list)
 613 {
 614         struct trace_event *e;
 615         int last = __TRACE_LAST_TYPE;
 616
 617         if (list_empty(&ftrace_event_list)) {
 618                 *list = &ftrace_event_list;
 619                 return last + 1;
 620         }
 621
 622         /*
 623          * We used up all possible max events,
 624          * lets see if somebody freed one.
 625          */
 626         list_for_each_entry(e, &ftrace_event_list, list) {
 627                 if (e->type != last + 1)
 628                         break;
 629                 last++;
 630         }
 631
 632         /* Did we used up all 65 thousand events??? */
 633         if ((last + 1) > FTRACE_MAX_EVENT)
 634                 return 0;
 635
 636         *list = &e->list;
 637         return last + 1;
 638 }
 639
 640 void trace_event_read_lock(void)
 641 {
 642         down_read(&trace_event_sem);
 643 }
 644
 645 void trace_event_read_unlock(void)
 646 {
 647         up_read(&trace_event_sem);
 648 }
 649
 650 /**
 651  * register_ftrace_event - register output for an event type
 652  * @event: the event type to register
 653  *
 654  * Event types are stored in a hash and this hash is used to
 655  * find a way to print an event. If the @event->type is set
 656  * then it will use that type, otherwise it will assign a
 657  * type to use.
 658  *
 659  * If you assign your own type, please make sure it is added
 660  * to the trace_type enum in trace.h, to avoid collisions
 661  * with the dynamic types.
 662  *
 663  * Returns the event type number or zero on error.
 664  */
 665 int register_ftrace_event(struct trace_event *event)
 666 {
 667         unsigned key;
 668         int ret = 0;
 669
 670         down_write(&trace_event_sem);
 671
 672         if (WARN_ON(!event))
 673                 goto out;
 674
 675         if (WARN_ON(!event->funcs))
 676                 goto out;
 677
 678         INIT_LIST_HEAD(&event->list);
 679
 680         if (!event->type) {
 681                 struct list_head *list = NULL;
 682
 683                 if (next_event_type > FTRACE_MAX_EVENT) {
 684
 685                         event->type = trace_search_list(&list);
 686                         if (!event->type)
 687                                 goto out;
 688
 689                 } else {
 690
 691                         event->type = next_event_type++;
 692                         list = &ftrace_event_list;
 693                 }
 694
 695                 if (WARN_ON(ftrace_find_event(event->type)))
 696                         goto out;
 697
 698                 list_add_tail(&event->list, list);
 699
 700         } else if (event->type > __TRACE_LAST_TYPE) {
 701                 printk(KERN_WARNING "Need to add type to trace.h\n");
 702                 WARN_ON(1);
 703                 goto out;
 704         } else {
 705                 /* Is this event already used */
 706                 if (ftrace_find_event(event->type))
 707                         goto out;
 708         }
 709
 710         if (event->funcs->trace == NULL)
 711                 event->funcs->trace = trace_nop_print;
 712         if (event->funcs->raw == NULL)
 713                 event->funcs->raw = trace_nop_print;
 714         if (event->funcs->hex == NULL)
 715                 event->funcs->hex = trace_nop_print;
 716         if (event->funcs->binary == NULL)
 717                 event->funcs->binary = trace_nop_print;
 718
 719         key = event->type & (EVENT_HASHSIZE - 1);
 720
 721         hlist_add_head(&event->node, &event_hash[key]);
 722
 723         ret = event->type;
 724  out:
 725         up_write(&trace_event_sem);
 726
 727         return ret;
 728 }
 729 EXPORT_SYMBOL_GPL(register_ftrace_event);
 730
 731 /*
 732  * Used by module code with the trace_event_sem held for write.
 733  */
 734 int __unregister_ftrace_event(struct trace_event *event)
 735 {
 736         hlist_del(&event->node);
 737         list_del(&event->list);
 738         return 0;
 739 }
 740
 741 /**
 742  * unregister_ftrace_event - remove a no longer used event
 743  * @event: the event to remove
 744  */
 745 int unregister_ftrace_event(struct trace_event *event)
 746 {
 747         down_write(&trace_event_sem);
 748         __unregister_ftrace_event(event);
 749         up_write(&trace_event_sem);
 750
 751         return 0;
 752 }
 753 EXPORT_SYMBOL_GPL(unregister_ftrace_event);
 754
 755 /*
 756  * Standard events
 757  */
 758
 759 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
 760                                   struct trace_event *event)
 761 {
 762         trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
 763
 764         return trace_handle_return(&iter->seq);
 765 }
 766
 767 /* TRACE_FN */
 768 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
 769                                         struct trace_event *event)
 770 {
 771         struct ftrace_entry *field;
 772         struct trace_seq *s = &iter->seq;
 773
 774         trace_assign_type(field, iter->ent);
 775
 776         seq_print_ip_sym(s, field->ip, flags);
 777
 778         if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
 779                 trace_seq_puts(s, " <-");
 780                 seq_print_ip_sym(s, field->parent_ip, flags);
 781         }
 782
 783         trace_seq_putc(s, '\n');
 784
 785         return trace_handle_return(s);
 786 }
 787
 788 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
 789                                       struct trace_event *event)
 790 {
 791         struct ftrace_entry *field;
 792
 793         trace_assign_type(field, iter->ent);
 794
 795         trace_seq_printf(&iter->seq, "%lx %lx\n",
 796                          field->ip,
 797                          field->parent_ip);
 798
 799         return trace_handle_return(&iter->seq);
 800 }
 801
 802 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
 803                                       struct trace_event *event)
 804 {
 805         struct ftrace_entry *field;
 806         struct trace_seq *s = &iter->seq;
 807
 808         trace_assign_type(field, iter->ent);
 809
 810         SEQ_PUT_HEX_FIELD(s, field->ip);
 811         SEQ_PUT_HEX_FIELD(s, field->parent_ip);
 812
 813         return trace_handle_return(s);
 814 }
 815
 816 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
 817                                       struct trace_event *event)
 818 {
 819         struct ftrace_entry *field;
 820         struct trace_seq *s = &iter->seq;
 821
 822         trace_assign_type(field, iter->ent);
 823
 824         SEQ_PUT_FIELD(s, field->ip);
 825         SEQ_PUT_FIELD(s, field->parent_ip);
 826
 827         return trace_handle_return(s);
 828 }
 829
 830 static struct trace_event_functions trace_fn_funcs = {
 831         .trace          = trace_fn_trace,
 832         .raw            = trace_fn_raw,
 833         .hex            = trace_fn_hex,
 834         .binary         = trace_fn_bin,
 835 };
 836
 837 static struct trace_event trace_fn_event = {
 838         .type           = TRACE_FN,
 839         .funcs          = &trace_fn_funcs,
 840 };
 841
 842 /* TRACE_CTX an TRACE_WAKE */
 843 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
 844                                              char *delim)
 845 {
 846         struct ctx_switch_entry *field;
 847         char comm[TASK_COMM_LEN];
 848         int S, T;
 849
 850
 851         trace_assign_type(field, iter->ent);
 852
 853         T = task_state_char(field->next_state);
 854         S = task_state_char(field->prev_state);
 855         trace_find_cmdline(field->next_pid, comm);
 856         trace_seq_printf(&iter->seq,
 857                          " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
 858                          field->prev_pid,
 859                          field->prev_prio,
 860                          S, delim,
 861                          field->next_cpu,
 862                          field->next_pid,
 863                          field->next_prio,
 864                          T, comm);
 865
 866         return trace_handle_return(&iter->seq);
 867 }
 868
 869 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
 870                                          struct trace_event *event)
 871 {
 872         return trace_ctxwake_print(iter, "==>");
 873 }
 874
 875 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
 876                                           int flags, struct trace_event *event)
 877 {
 878         return trace_ctxwake_print(iter, "  +");
 879 }
 880
 881 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
 882 {
 883         struct ctx_switch_entry *field;
 884         int T;
 885
 886         trace_assign_type(field, iter->ent);
 887
 888         if (!S)
 889                 S = task_state_char(field->prev_state);
 890         T = task_state_char(field->next_state);
 891         trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
 892                          field->prev_pid,
 893                          field->prev_prio,
 894                          S,
 895                          field->next_cpu,
 896                          field->next_pid,
 897                          field->next_prio,
 898                          T);
 899
 900         return trace_handle_return(&iter->seq);
 901 }
 902
 903 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
 904                                        struct trace_event *event)
 905 {
 906         return trace_ctxwake_raw(iter, 0);
 907 }
 908
 909 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
 910                                         struct trace_event *event)
 911 {
 912         return trace_ctxwake_raw(iter, '+');
 913 }
 914
 915
 916 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
 917 {
 918         struct ctx_switch_entry *field;
 919         struct trace_seq *s = &iter->seq;
 920         int T;
 921
 922         trace_assign_type(field, iter->ent);
 923
 924         if (!S)
 925                 S = task_state_char(field->prev_state);
 926         T = task_state_char(field->next_state);
 927
 928         SEQ_PUT_HEX_FIELD(s, field->prev_pid);
 929         SEQ_PUT_HEX_FIELD(s, field->prev_prio);
 930         SEQ_PUT_HEX_FIELD(s, S);
 931         SEQ_PUT_HEX_FIELD(s, field->next_cpu);
 932         SEQ_PUT_HEX_FIELD(s, field->next_pid);
 933         SEQ_PUT_HEX_FIELD(s, field->next_prio);
 934         SEQ_PUT_HEX_FIELD(s, T);
 935
 936         return trace_handle_return(s);
 937 }
 938
 939 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
 940                                        struct trace_event *event)
 941 {
 942         return trace_ctxwake_hex(iter, 0);
 943 }
 944
 945 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
 946                                         struct trace_event *event)
 947 {
 948         return trace_ctxwake_hex(iter, '+');
 949 }
 950
 951 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
 952                                            int flags, struct trace_event *event)
 953 {
 954         struct ctx_switch_entry *field;
 955         struct trace_seq *s = &iter->seq;
 956
 957         trace_assign_type(field, iter->ent);
 958
 959         SEQ_PUT_FIELD(s, field->prev_pid);
 960         SEQ_PUT_FIELD(s, field->prev_prio);
 961         SEQ_PUT_FIELD(s, field->prev_state);
 962         SEQ_PUT_FIELD(s, field->next_cpu);
 963         SEQ_PUT_FIELD(s, field->next_pid);
 964         SEQ_PUT_FIELD(s, field->next_prio);
 965         SEQ_PUT_FIELD(s, field->next_state);
 966
 967         return trace_handle_return(s);
 968 }
 969
 970 static struct trace_event_functions trace_ctx_funcs = {
 971         .trace          = trace_ctx_print,
 972         .raw            = trace_ctx_raw,
 973         .hex            = trace_ctx_hex,
 974         .binary         = trace_ctxwake_bin,
 975 };
 976
 977 static struct trace_event trace_ctx_event = {
 978         .type           = TRACE_CTX,
 979         .funcs          = &trace_ctx_funcs,
 980 };
 981
 982 static struct trace_event_functions trace_wake_funcs = {
 983         .trace          = trace_wake_print,
 984         .raw            = trace_wake_raw,
 985         .hex            = trace_wake_hex,
 986         .binary         = trace_ctxwake_bin,
 987 };
 988
 989 static struct trace_event trace_wake_event = {
 990         .type           = TRACE_WAKE,
 991         .funcs          = &trace_wake_funcs,
 992 };
 993
 994 /* TRACE_STACK */
 995
 996 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
 997                                            int flags, struct trace_event *event)
 998 {
 999         struct stack_entry *field;
1000         struct trace_seq *s = &iter->seq;
1001         unsigned long *p;
1002         unsigned long *end;
1003
1004         trace_assign_type(field, iter->ent);
1005         end = (unsigned long *)((long)iter->ent + iter->ent_size);
1006
1007         trace_seq_puts(s, "<stack trace>\n");
1008
1009         for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1010
1011                 if (trace_seq_has_overflowed(s))
1012                         break;
1013
1014                 trace_seq_puts(s, " => ");
1015                 seq_print_ip_sym(s, *p, flags);
1016                 trace_seq_putc(s, '\n');
1017         }
1018
1019         return trace_handle_return(s);
1020 }
1021
1022 static struct trace_event_functions trace_stack_funcs = {
1023         .trace          = trace_stack_print,
1024 };
1025
1026 static struct trace_event trace_stack_event = {
1027         .type           = TRACE_STACK,
1028         .funcs          = &trace_stack_funcs,
1029 };
1030
1031 /* TRACE_USER_STACK */
1032 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1033                                                 int flags, struct trace_event *event)
1034 {
1035         struct userstack_entry *field;
1036         struct trace_seq *s = &iter->seq;
1037
1038         trace_assign_type(field, iter->ent);
1039
1040         trace_seq_puts(s, "<user stack trace>\n");
1041         seq_print_userip_objs(field, s, flags);
1042
1043         return trace_handle_return(s);
1044 }
1045
1046 static struct trace_event_functions trace_user_stack_funcs = {
1047         .trace          = trace_user_stack_print,
1048 };
1049
1050 static struct trace_event trace_user_stack_event = {
1051         .type           = TRACE_USER_STACK,
1052         .funcs          = &trace_user_stack_funcs,
1053 };
1054
1055 /* TRACE_BPUTS */
1056 static enum print_line_t
1057 trace_bputs_print(struct trace_iterator *iter, int flags,
1058                    struct trace_event *event)
1059 {
1060         struct trace_entry *entry = iter->ent;
1061         struct trace_seq *s = &iter->seq;
1062         struct bputs_entry *field;
1063
1064         trace_assign_type(field, entry);
1065
1066         seq_print_ip_sym(s, field->ip, flags);
1067         trace_seq_puts(s, ": ");
1068         trace_seq_puts(s, field->str);
1069
1070         return trace_handle_return(s);
1071 }
1072
1073
1074 static enum print_line_t
1075 trace_bputs_raw(struct trace_iterator *iter, int flags,
1076                 struct trace_event *event)
1077 {
1078         struct bputs_entry *field;
1079         struct trace_seq *s = &iter->seq;
1080
1081         trace_assign_type(field, iter->ent);
1082
1083         trace_seq_printf(s, ": %lx : ", field->ip);
1084         trace_seq_puts(s, field->str);
1085
1086         return trace_handle_return(s);
1087 }
1088
1089 static struct trace_event_functions trace_bputs_funcs = {
1090         .trace          = trace_bputs_print,
1091         .raw            = trace_bputs_raw,
1092 };
1093
1094 static struct trace_event trace_bputs_event = {
1095         .type           = TRACE_BPUTS,
1096         .funcs          = &trace_bputs_funcs,
1097 };
1098
1099 /* TRACE_BPRINT */
1100 static enum print_line_t
1101 trace_bprint_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 bprint_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_bprintf(s, field->fmt, field->buf);
1113
1114         return trace_handle_return(s);
1115 }
1116
1117
1118 static enum print_line_t
1119 trace_bprint_raw(struct trace_iterator *iter, int flags,
1120                  struct trace_event *event)
1121 {
1122         struct bprint_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_bprintf(s, field->fmt, field->buf);
1129
1130         return trace_handle_return(s);
1131 }
1132
1133 static struct trace_event_functions trace_bprint_funcs = {
1134         .trace          = trace_bprint_print,
1135         .raw            = trace_bprint_raw,
1136 };
1137
1138 static struct trace_event trace_bprint_event = {
1139         .type           = TRACE_BPRINT,
1140         .funcs          = &trace_bprint_funcs,
1141 };
1142
1143 /* TRACE_PRINT */
1144 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1145                                            int flags, struct trace_event *event)
1146 {
1147         struct print_entry *field;
1148         struct trace_seq *s = &iter->seq;
1149
1150         trace_assign_type(field, iter->ent);
1151
1152         seq_print_ip_sym(s, field->ip, flags);
1153         trace_seq_printf(s, ": %s", field->buf);
1154
1155         return trace_handle_return(s);
1156 }
1157
1158 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1159                                          struct trace_event *event)
1160 {
1161         struct print_entry *field;
1162
1163         trace_assign_type(field, iter->ent);
1164
1165         trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
1166
1167         return trace_handle_return(&iter->seq);
1168 }
1169
1170 static struct trace_event_functions trace_print_funcs = {
1171         .trace          = trace_print_print,
1172         .raw            = trace_print_raw,
1173 };
1174
1175 static struct trace_event trace_print_event = {
1176         .type           = TRACE_PRINT,
1177         .funcs          = &trace_print_funcs,
1178 };
1179
1180
1181 static struct trace_event *events[] __initdata = {
1182         &trace_fn_event,
1183         &trace_ctx_event,
1184         &trace_wake_event,
1185         &trace_stack_event,
1186         &trace_user_stack_event,
1187         &trace_bputs_event,
1188         &trace_bprint_event,
1189         &trace_print_event,
1190         NULL
1191 };
1192
1193 __init static int init_events(void)
1194 {
1195         struct trace_event *event;
1196         int i, ret;
1197
1198         for (i = 0; events[i]; i++) {
1199                 event = events[i];
1200
1201                 ret = register_ftrace_event(event);
1202                 if (!ret) {
1203                         printk(KERN_WARNING "event %d failed to register\n",
1204                                event->type);
1205                         WARN_ON_ONCE(1);
1206                 }
1207         }
1208
1209         return 0;
1210 }
1211 early_initcall(init_events);