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_flags_seq_u64(struct trace_seq *p, const char *delim,
 128                       unsigned long long flags,
 129                       const struct trace_print_flags_u64 *flag_array)
 130 {
 131         unsigned long long mask;
 132         const char *str;
 133         const char *ret = trace_seq_buffer_ptr(p);
 134         int i, first = 1;
 135
 136         for (i = 0;  flag_array[i].name && flags; i++) {
 137
 138                 mask = flag_array[i].mask;
 139                 if ((flags & mask) != mask)
 140                         continue;
 141
 142                 str = flag_array[i].name;
 143                 flags &= ~mask;
 144                 if (!first && delim)
 145                         trace_seq_puts(p, delim);
 146                 else
 147                         first = 0;
 148                 trace_seq_puts(p, str);
 149         }
 150
 151         /* check for left over flags */
 152         if (flags) {
 153                 if (!first && delim)
 154                         trace_seq_puts(p, delim);
 155                 trace_seq_printf(p, "0x%llx", flags);
 156         }
 157
 158         trace_seq_putc(p, 0);
 159
 160         return ret;
 161 }
 162 EXPORT_SYMBOL(trace_print_flags_seq_u64);
 163
 164 const char *
 165 trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
 166                          const struct trace_print_flags_u64 *symbol_array)
 167 {
 168         int i;
 169         const char *ret = trace_seq_buffer_ptr(p);
 170
 171         for (i = 0;  symbol_array[i].name; i++) {
 172
 173                 if (val != symbol_array[i].mask)
 174                         continue;
 175
 176                 trace_seq_puts(p, symbol_array[i].name);
 177                 break;
 178         }
 179
 180         if (ret == (const char *)(trace_seq_buffer_ptr(p)))
 181                 trace_seq_printf(p, "0x%llx", val);
 182
 183         trace_seq_putc(p, 0);
 184
 185         return ret;
 186 }
 187 EXPORT_SYMBOL(trace_print_symbols_seq_u64);
 188 #endif
 189
 190 const char *
 191 trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
 192                         unsigned int bitmask_size)
 193 {
 194         const char *ret = trace_seq_buffer_ptr(p);
 195
 196         trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
 197         trace_seq_putc(p, 0);
 198
 199         return ret;
 200 }
 201 EXPORT_SYMBOL_GPL(trace_print_bitmask_seq);
 202
 203 /**
 204  * trace_print_hex_seq - print buffer as hex sequence
 205  * @p: trace seq struct to write to
 206  * @buf: The buffer to print
 207  * @buf_len: Length of @buf in bytes
 208  * @concatenate: Print @buf as single hex string or with spacing
 209  *
 210  * Prints the passed buffer as a hex sequence either as a whole,
 211  * single hex string if @concatenate is true or with spacing after
 212  * each byte in case @concatenate is false.
 213  */
 214 const char *
 215 trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len,
 216                     bool concatenate)
 217 {
 218         int i;
 219         const char *ret = trace_seq_buffer_ptr(p);
 220
 221         for (i = 0; i < buf_len; i++)
 222                 trace_seq_printf(p, "%s%2.2x", concatenate || i == 0 ? "" : " ",
 223                                  buf[i]);
 224         trace_seq_putc(p, 0);
 225
 226         return ret;
 227 }
 228 EXPORT_SYMBOL(trace_print_hex_seq);
 229
 230 const char *
 231 trace_print_array_seq(struct trace_seq *p, const void *buf, int count,
 232                       size_t el_size)
 233 {
 234         const char *ret = trace_seq_buffer_ptr(p);
 235         const char *prefix = "";
 236         void *ptr = (void *)buf;
 237         size_t buf_len = count * el_size;
 238
 239         trace_seq_putc(p, '{');
 240
 241         while (ptr < buf + buf_len) {
 242                 switch (el_size) {
 243                 case 1:
 244                         trace_seq_printf(p, "%s0x%x", prefix,
 245                                          *(u8 *)ptr);
 246                         break;
 247                 case 2:
 248                         trace_seq_printf(p, "%s0x%x", prefix,
 249                                          *(u16 *)ptr);
 250                         break;
 251                 case 4:
 252                         trace_seq_printf(p, "%s0x%x", prefix,
 253                                          *(u32 *)ptr);
 254                         break;
 255                 case 8:
 256                         trace_seq_printf(p, "%s0x%llx", prefix,
 257                                          *(u64 *)ptr);
 258                         break;
 259                 default:
 260                         trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size,
 261                                          *(u8 *)ptr);
 262                         el_size = 1;
 263                 }
 264                 prefix = ",";
 265                 ptr += el_size;
 266         }
 267
 268         trace_seq_putc(p, '}');
 269         trace_seq_putc(p, 0);
 270
 271         return ret;
 272 }
 273 EXPORT_SYMBOL(trace_print_array_seq);
 274
 275 int trace_raw_output_prep(struct trace_iterator *iter,
 276                           struct trace_event *trace_event)
 277 {
 278         struct trace_event_call *event;
 279         struct trace_seq *s = &iter->seq;
 280         struct trace_seq *p = &iter->tmp_seq;
 281         struct trace_entry *entry;
 282
 283         event = container_of(trace_event, struct trace_event_call, event);
 284         entry = iter->ent;
 285
 286         if (entry->type != event->event.type) {
 287                 WARN_ON_ONCE(1);
 288                 return TRACE_TYPE_UNHANDLED;
 289         }
 290
 291         trace_seq_init(p);
 292         trace_seq_printf(s, "%s: ", trace_event_name(event));
 293
 294         return trace_handle_return(s);
 295 }
 296 EXPORT_SYMBOL(trace_raw_output_prep);
 297
 298 static int trace_output_raw(struct trace_iterator *iter, char *name,
 299                             char *fmt, va_list ap)
 300 {
 301         struct trace_seq *s = &iter->seq;
 302
 303         trace_seq_printf(s, "%s: ", name);
 304         trace_seq_vprintf(s, fmt, ap);
 305
 306         return trace_handle_return(s);
 307 }
 308
 309 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
 310 {
 311         va_list ap;
 312         int ret;
 313
 314         va_start(ap, fmt);
 315         ret = trace_output_raw(iter, name, fmt, ap);
 316         va_end(ap);
 317
 318         return ret;
 319 }
 320 EXPORT_SYMBOL_GPL(trace_output_call);
 321
 322 #ifdef CONFIG_KRETPROBES
 323 static inline const char *kretprobed(const char *name)
 324 {
 325         static const char tramp_name[] = "kretprobe_trampoline";
 326         int size = sizeof(tramp_name);
 327
 328         if (strncmp(tramp_name, name, size) == 0)
 329                 return "[unknown/kretprobe'd]";
 330         return name;
 331 }
 332 #else
 333 static inline const char *kretprobed(const char *name)
 334 {
 335         return name;
 336 }
 337 #endif /* CONFIG_KRETPROBES */
 338
 339 static void
 340 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
 341 {
 342 #ifdef CONFIG_KALLSYMS
 343         char str[KSYM_SYMBOL_LEN];
 344         const char *name;
 345
 346         kallsyms_lookup(address, NULL, NULL, NULL, str);
 347
 348         name = kretprobed(str);
 349
 350         trace_seq_printf(s, fmt, name);
 351 #endif
 352 }
 353
 354 static void
 355 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
 356                      unsigned long address)
 357 {
 358 #ifdef CONFIG_KALLSYMS
 359         char str[KSYM_SYMBOL_LEN];
 360         const char *name;
 361
 362         sprint_symbol(str, address);
 363         name = kretprobed(str);
 364
 365         trace_seq_printf(s, fmt, name);
 366 #endif
 367 }
 368
 369 #ifndef CONFIG_64BIT
 370 # define IP_FMT "%08lx"
 371 #else
 372 # define IP_FMT "%016lx"
 373 #endif
 374
 375 static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
 376                              unsigned long ip, unsigned long sym_flags)
 377 {
 378         struct file *file = NULL;
 379         unsigned long vmstart = 0;
 380         int ret = 1;
 381
 382         if (s->full)
 383                 return 0;
 384
 385         if (mm) {
 386                 const struct vm_area_struct *vma;
 387
 388                 down_read(&mm->mmap_sem);
 389                 vma = find_vma(mm, ip);
 390                 if (vma) {
 391                         file = vma->vm_file;
 392                         vmstart = vma->vm_start;
 393                 }
 394                 if (file) {
 395                         ret = trace_seq_path(s, &file->f_path);
 396                         if (ret)
 397                                 trace_seq_printf(s, "[+0x%lx]",
 398                                                  ip - vmstart);
 399                 }
 400                 up_read(&mm->mmap_sem);
 401         }
 402         if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
 403                 trace_seq_printf(s, " <" IP_FMT ">", ip);
 404         return !trace_seq_has_overflowed(s);
 405 }
 406
 407 int
 408 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 409 {
 410         if (!ip) {
 411                 trace_seq_putc(s, '0');
 412                 goto out;
 413         }
 414
 415         if (sym_flags & TRACE_ITER_SYM_OFFSET)
 416                 seq_print_sym_offset(s, "%s", ip);
 417         else
 418                 seq_print_sym_short(s, "%s", ip);
 419
 420         if (sym_flags & TRACE_ITER_SYM_ADDR)
 421                 trace_seq_printf(s, " <" IP_FMT ">", ip);
 422
 423  out:
 424         return !trace_seq_has_overflowed(s);
 425 }
 426
 427 /**
 428  * trace_print_lat_fmt - print the irq, preempt and lockdep fields
 429  * @s: trace seq struct to write to
 430  * @entry: The trace entry field from the ring buffer
 431  *
 432  * Prints the generic fields of irqs off, in hard or softirq, preempt
 433  * count.
 434  */
 435 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 436 {
 437         char hardsoft_irq;
 438         char need_resched;
 439         char irqs_off;
 440         int hardirq;
 441         int softirq;
 442         int nmi;
 443
 444         nmi = entry->flags & TRACE_FLAG_NMI;
 445         hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 446         softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 447
 448         irqs_off =
 449                 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 450                 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 451                 '.';
 452
 453         switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
 454                                 TRACE_FLAG_PREEMPT_RESCHED)) {
 455         case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 456                 need_resched = 'N';
 457                 break;
 458         case TRACE_FLAG_NEED_RESCHED:
 459                 need_resched = 'n';
 460                 break;
 461         case TRACE_FLAG_PREEMPT_RESCHED:
 462                 need_resched = 'p';
 463                 break;
 464         default:
 465                 need_resched = '.';
 466                 break;
 467         }
 468
 469         hardsoft_irq =
 470                 (nmi && hardirq)     ? 'Z' :
 471                 nmi                  ? 'z' :
 472                 (hardirq && softirq) ? 'H' :
 473                 hardirq              ? 'h' :
 474                 softirq              ? 's' :
 475                                        '.' ;
 476
 477         trace_seq_printf(s, "%c%c%c",
 478                          irqs_off, need_resched, hardsoft_irq);
 479
 480         if (entry->preempt_count)
 481                 trace_seq_printf(s, "%x", entry->preempt_count);
 482         else
 483                 trace_seq_putc(s, '.');
 484
 485         return !trace_seq_has_overflowed(s);
 486 }
 487
 488 static int
 489 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 490 {
 491         char comm[TASK_COMM_LEN];
 492
 493         trace_find_cmdline(entry->pid, comm);
 494
 495         trace_seq_printf(s, "%8.8s-%-5d %3d",
 496                          comm, entry->pid, cpu);
 497
 498         return trace_print_lat_fmt(s, entry);
 499 }
 500
 501 #undef MARK
 502 #define MARK(v, s) {.val = v, .sym = s}
 503 /* trace overhead mark */
 504 static const struct trace_mark {
 505         unsigned long long      val; /* unit: nsec */
 506         char                    sym;
 507 } mark[] = {
 508         MARK(1000000000ULL      , '$'), /* 1 sec */
 509         MARK(100000000ULL       , '@'), /* 100 msec */
 510         MARK(10000000ULL        , '*'), /* 10 msec */
 511         MARK(1000000ULL         , '#'), /* 1000 usecs */
 512         MARK(100000ULL          , '!'), /* 100 usecs */
 513         MARK(10000ULL           , '+'), /* 10 usecs */
 514 };
 515 #undef MARK
 516
 517 char trace_find_mark(unsigned long long d)
 518 {
 519         int i;
 520         int size = ARRAY_SIZE(mark);
 521
 522         for (i = 0; i < size; i++) {
 523                 if (d > mark[i].val)
 524                         break;
 525         }
 526
 527         return (i == size) ? ' ' : mark[i].sym;
 528 }
 529
 530 static int
 531 lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
 532 {
 533         struct trace_array *tr = iter->tr;
 534         unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE;
 535         unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
 536         unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start;
 537         unsigned long long rel_ts = next_ts - iter->ts;
 538         struct trace_seq *s = &iter->seq;
 539
 540         if (in_ns) {
 541                 abs_ts = ns2usecs(abs_ts);
 542                 rel_ts = ns2usecs(rel_ts);
 543         }
 544
 545         if (verbose && in_ns) {
 546                 unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
 547                 unsigned long abs_msec = (unsigned long)abs_ts;
 548                 unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
 549                 unsigned long rel_msec = (unsigned long)rel_ts;
 550
 551                 trace_seq_printf(
 552                         s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
 553                         ns2usecs(iter->ts),
 554                         abs_msec, abs_usec,
 555                         rel_msec, rel_usec);
 556
 557         } else if (verbose && !in_ns) {
 558                 trace_seq_printf(
 559                         s, "[%016llx] %lld (+%lld): ",
 560                         iter->ts, abs_ts, rel_ts);
 561
 562         } else if (!verbose && in_ns) {
 563                 trace_seq_printf(
 564                         s, " %4lldus%c: ",
 565                         abs_ts,
 566                         trace_find_mark(rel_ts * NSEC_PER_USEC));
 567
 568         } else { /* !verbose && !in_ns */
 569                 trace_seq_printf(s, " %4lld: ", abs_ts);
 570         }
 571
 572         return !trace_seq_has_overflowed(s);
 573 }
 574
 575 int trace_print_context(struct trace_iterator *iter)
 576 {
 577         struct trace_array *tr = iter->tr;
 578         struct trace_seq *s = &iter->seq;
 579         struct trace_entry *entry = iter->ent;
 580         unsigned long long t;
 581         unsigned long secs, usec_rem;
 582         char comm[TASK_COMM_LEN];
 583
 584         trace_find_cmdline(entry->pid, comm);
 585
 586         trace_seq_printf(s, "%16s-%-5d [%03d] ",
 587                                comm, entry->pid, iter->cpu);
 588
 589         if (tr->trace_flags & TRACE_ITER_IRQ_INFO)
 590                 trace_print_lat_fmt(s, entry);
 591
 592         if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
 593                 t = ns2usecs(iter->ts);
 594                 usec_rem = do_div(t, USEC_PER_SEC);
 595                 secs = (unsigned long)t;
 596                 trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
 597         } else
 598                 trace_seq_printf(s, " %12llu: ", iter->ts);
 599
 600         return !trace_seq_has_overflowed(s);
 601 }
 602
 603 int trace_print_lat_context(struct trace_iterator *iter)
 604 {
 605         struct trace_array *tr = iter->tr;
 606         /* trace_find_next_entry will reset ent_size */
 607         int ent_size = iter->ent_size;
 608         struct trace_seq *s = &iter->seq;
 609         u64 next_ts;
 610         struct trace_entry *entry = iter->ent,
 611                            *next_entry = trace_find_next_entry(iter, NULL,
 612                                                                &next_ts);
 613         unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE);
 614
 615         /* Restore the original ent_size */
 616         iter->ent_size = ent_size;
 617
 618         if (!next_entry)
 619                 next_ts = iter->ts;
 620
 621         if (verbose) {
 622                 char comm[TASK_COMM_LEN];
 623
 624                 trace_find_cmdline(entry->pid, comm);
 625
 626                 trace_seq_printf(
 627                         s, "%16s %5d %3d %d %08x %08lx ",
 628                         comm, entry->pid, iter->cpu, entry->flags,
 629                         entry->preempt_count, iter->idx);
 630         } else {
 631                 lat_print_generic(s, entry, iter->cpu);
 632         }
 633
 634         lat_print_timestamp(iter, next_ts);
 635
 636         return !trace_seq_has_overflowed(s);
 637 }
 638
 639 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
 640
 641 static int task_state_char(unsigned long state)
 642 {
 643         int bit = state ? __ffs(state) + 1 : 0;
 644
 645         return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
 646 }
 647
 648 /**
 649  * ftrace_find_event - find a registered event
 650  * @type: the type of event to look for
 651  *
 652  * Returns an event of type @type otherwise NULL
 653  * Called with trace_event_read_lock() held.
 654  */
 655 struct trace_event *ftrace_find_event(int type)
 656 {
 657         struct trace_event *event;
 658         unsigned key;
 659
 660         key = type & (EVENT_HASHSIZE - 1);
 661
 662         hlist_for_each_entry(event, &event_hash[key], node) {
 663                 if (event->type == type)
 664                         return event;
 665         }
 666
 667         return NULL;
 668 }
 669
 670 static LIST_HEAD(ftrace_event_list);
 671
 672 static int trace_search_list(struct list_head **list)
 673 {
 674         struct trace_event *e;
 675         int last = __TRACE_LAST_TYPE;
 676
 677         if (list_empty(&ftrace_event_list)) {
 678                 *list = &ftrace_event_list;
 679                 return last + 1;
 680         }
 681
 682         /*
 683          * We used up all possible max events,
 684          * lets see if somebody freed one.
 685          */
 686         list_for_each_entry(e, &ftrace_event_list, list) {
 687                 if (e->type != last + 1)
 688                         break;
 689                 last++;
 690         }
 691
 692         /* Did we used up all 65 thousand events??? */
 693         if ((last + 1) > TRACE_EVENT_TYPE_MAX)
 694                 return 0;
 695
 696         *list = &e->list;
 697         return last + 1;
 698 }
 699
 700 void trace_event_read_lock(void)
 701 {
 702         down_read(&trace_event_sem);
 703 }
 704
 705 void trace_event_read_unlock(void)
 706 {
 707         up_read(&trace_event_sem);
 708 }
 709
 710 /**
 711  * register_trace_event - register output for an event type
 712  * @event: the event type to register
 713  *
 714  * Event types are stored in a hash and this hash is used to
 715  * find a way to print an event. If the @event->type is set
 716  * then it will use that type, otherwise it will assign a
 717  * type to use.
 718  *
 719  * If you assign your own type, please make sure it is added
 720  * to the trace_type enum in trace.h, to avoid collisions
 721  * with the dynamic types.
 722  *
 723  * Returns the event type number or zero on error.
 724  */
 725 int register_trace_event(struct trace_event *event)
 726 {
 727         unsigned key;
 728         int ret = 0;
 729
 730         down_write(&trace_event_sem);
 731
 732         if (WARN_ON(!event))
 733                 goto out;
 734
 735         if (WARN_ON(!event->funcs))
 736                 goto out;
 737
 738         INIT_LIST_HEAD(&event->list);
 739
 740         if (!event->type) {
 741                 struct list_head *list = NULL;
 742
 743                 if (next_event_type > TRACE_EVENT_TYPE_MAX) {
 744
 745                         event->type = trace_search_list(&list);
 746                         if (!event->type)
 747                                 goto out;
 748
 749                 } else {
 750
 751                         event->type = next_event_type++;
 752                         list = &ftrace_event_list;
 753                 }
 754
 755                 if (WARN_ON(ftrace_find_event(event->type)))
 756                         goto out;
 757
 758                 list_add_tail(&event->list, list);
 759
 760         } else if (event->type > __TRACE_LAST_TYPE) {
 761                 printk(KERN_WARNING "Need to add type to trace.h\n");
 762                 WARN_ON(1);
 763                 goto out;
 764         } else {
 765                 /* Is this event already used */
 766                 if (ftrace_find_event(event->type))
 767                         goto out;
 768         }
 769
 770         if (event->funcs->trace == NULL)
 771                 event->funcs->trace = trace_nop_print;
 772         if (event->funcs->raw == NULL)
 773                 event->funcs->raw = trace_nop_print;
 774         if (event->funcs->hex == NULL)
 775                 event->funcs->hex = trace_nop_print;
 776         if (event->funcs->binary == NULL)
 777                 event->funcs->binary = trace_nop_print;
 778
 779         key = event->type & (EVENT_HASHSIZE - 1);
 780
 781         hlist_add_head(&event->node, &event_hash[key]);
 782
 783         ret = event->type;
 784  out:
 785         up_write(&trace_event_sem);
 786
 787         return ret;
 788 }
 789 EXPORT_SYMBOL_GPL(register_trace_event);
 790
 791 /*
 792  * Used by module code with the trace_event_sem held for write.
 793  */
 794 int __unregister_trace_event(struct trace_event *event)
 795 {
 796         hlist_del(&event->node);
 797         list_del(&event->list);
 798         return 0;
 799 }
 800
 801 /**
 802  * unregister_trace_event - remove a no longer used event
 803  * @event: the event to remove
 804  */
 805 int unregister_trace_event(struct trace_event *event)
 806 {
 807         down_write(&trace_event_sem);
 808         __unregister_trace_event(event);
 809         up_write(&trace_event_sem);
 810
 811         return 0;
 812 }
 813 EXPORT_SYMBOL_GPL(unregister_trace_event);
 814
 815 /*
 816  * Standard events
 817  */
 818
 819 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
 820                                   struct trace_event *event)
 821 {
 822         trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
 823
 824         return trace_handle_return(&iter->seq);
 825 }
 826
 827 /* TRACE_FN */
 828 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
 829                                         struct trace_event *event)
 830 {
 831         struct ftrace_entry *field;
 832         struct trace_seq *s = &iter->seq;
 833
 834         trace_assign_type(field, iter->ent);
 835
 836         seq_print_ip_sym(s, field->ip, flags);
 837
 838         if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
 839                 trace_seq_puts(s, " <-");
 840                 seq_print_ip_sym(s, field->parent_ip, flags);
 841         }
 842
 843         trace_seq_putc(s, '\n');
 844
 845         return trace_handle_return(s);
 846 }
 847
 848 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
 849                                       struct trace_event *event)
 850 {
 851         struct ftrace_entry *field;
 852
 853         trace_assign_type(field, iter->ent);
 854
 855         trace_seq_printf(&iter->seq, "%lx %lx\n",
 856                          field->ip,
 857                          field->parent_ip);
 858
 859         return trace_handle_return(&iter->seq);
 860 }
 861
 862 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
 863                                       struct trace_event *event)
 864 {
 865         struct ftrace_entry *field;
 866         struct trace_seq *s = &iter->seq;
 867
 868         trace_assign_type(field, iter->ent);
 869
 870         SEQ_PUT_HEX_FIELD(s, field->ip);
 871         SEQ_PUT_HEX_FIELD(s, field->parent_ip);
 872
 873         return trace_handle_return(s);
 874 }
 875
 876 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
 877                                       struct trace_event *event)
 878 {
 879         struct ftrace_entry *field;
 880         struct trace_seq *s = &iter->seq;
 881
 882         trace_assign_type(field, iter->ent);
 883
 884         SEQ_PUT_FIELD(s, field->ip);
 885         SEQ_PUT_FIELD(s, field->parent_ip);
 886
 887         return trace_handle_return(s);
 888 }
 889
 890 static struct trace_event_functions trace_fn_funcs = {
 891         .trace          = trace_fn_trace,
 892         .raw            = trace_fn_raw,
 893         .hex            = trace_fn_hex,
 894         .binary         = trace_fn_bin,
 895 };
 896
 897 static struct trace_event trace_fn_event = {
 898         .type           = TRACE_FN,
 899         .funcs          = &trace_fn_funcs,
 900 };
 901
 902 /* TRACE_CTX an TRACE_WAKE */
 903 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
 904                                              char *delim)
 905 {
 906         struct ctx_switch_entry *field;
 907         char comm[TASK_COMM_LEN];
 908         int S, T;
 909
 910
 911         trace_assign_type(field, iter->ent);
 912
 913         T = task_state_char(field->next_state);
 914         S = task_state_char(field->prev_state);
 915         trace_find_cmdline(field->next_pid, comm);
 916         trace_seq_printf(&iter->seq,
 917                          " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
 918                          field->prev_pid,
 919                          field->prev_prio,
 920                          S, delim,
 921                          field->next_cpu,
 922                          field->next_pid,
 923                          field->next_prio,
 924                          T, comm);
 925
 926         return trace_handle_return(&iter->seq);
 927 }
 928
 929 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
 930                                          struct trace_event *event)
 931 {
 932         return trace_ctxwake_print(iter, "==>");
 933 }
 934
 935 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
 936                                           int flags, struct trace_event *event)
 937 {
 938         return trace_ctxwake_print(iter, "  +");
 939 }
 940
 941 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
 942 {
 943         struct ctx_switch_entry *field;
 944         int T;
 945
 946         trace_assign_type(field, iter->ent);
 947
 948         if (!S)
 949                 S = task_state_char(field->prev_state);
 950         T = task_state_char(field->next_state);
 951         trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
 952                          field->prev_pid,
 953                          field->prev_prio,
 954                          S,
 955                          field->next_cpu,
 956                          field->next_pid,
 957                          field->next_prio,
 958                          T);
 959
 960         return trace_handle_return(&iter->seq);
 961 }
 962
 963 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
 964                                        struct trace_event *event)
 965 {
 966         return trace_ctxwake_raw(iter, 0);
 967 }
 968
 969 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
 970                                         struct trace_event *event)
 971 {
 972         return trace_ctxwake_raw(iter, '+');
 973 }
 974
 975
 976 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
 977 {
 978         struct ctx_switch_entry *field;
 979         struct trace_seq *s = &iter->seq;
 980         int T;
 981
 982         trace_assign_type(field, iter->ent);
 983
 984         if (!S)
 985                 S = task_state_char(field->prev_state);
 986         T = task_state_char(field->next_state);
 987
 988         SEQ_PUT_HEX_FIELD(s, field->prev_pid);
 989         SEQ_PUT_HEX_FIELD(s, field->prev_prio);
 990         SEQ_PUT_HEX_FIELD(s, S);
 991         SEQ_PUT_HEX_FIELD(s, field->next_cpu);
 992         SEQ_PUT_HEX_FIELD(s, field->next_pid);
 993         SEQ_PUT_HEX_FIELD(s, field->next_prio);
 994         SEQ_PUT_HEX_FIELD(s, T);
 995
 996         return trace_handle_return(s);
 997 }
 998
 999 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1000                                        struct trace_event *event)
1001 {
1002         return trace_ctxwake_hex(iter, 0);
1003 }
1004
1005 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1006                                         struct trace_event *event)
1007 {
1008         return trace_ctxwake_hex(iter, '+');
1009 }
1010
1011 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1012                                            int flags, struct trace_event *event)
1013 {
1014         struct ctx_switch_entry *field;
1015         struct trace_seq *s = &iter->seq;
1016
1017         trace_assign_type(field, iter->ent);
1018
1019         SEQ_PUT_FIELD(s, field->prev_pid);
1020         SEQ_PUT_FIELD(s, field->prev_prio);
1021         SEQ_PUT_FIELD(s, field->prev_state);
1022         SEQ_PUT_FIELD(s, field->next_cpu);
1023         SEQ_PUT_FIELD(s, field->next_pid);
1024         SEQ_PUT_FIELD(s, field->next_prio);
1025         SEQ_PUT_FIELD(s, field->next_state);
1026
1027         return trace_handle_return(s);
1028 }
1029
1030 static struct trace_event_functions trace_ctx_funcs = {
1031         .trace          = trace_ctx_print,
1032         .raw            = trace_ctx_raw,
1033         .hex            = trace_ctx_hex,
1034         .binary         = trace_ctxwake_bin,
1035 };
1036
1037 static struct trace_event trace_ctx_event = {
1038         .type           = TRACE_CTX,
1039         .funcs          = &trace_ctx_funcs,
1040 };
1041
1042 static struct trace_event_functions trace_wake_funcs = {
1043         .trace          = trace_wake_print,
1044         .raw            = trace_wake_raw,
1045         .hex            = trace_wake_hex,
1046         .binary         = trace_ctxwake_bin,
1047 };
1048
1049 static struct trace_event trace_wake_event = {
1050         .type           = TRACE_WAKE,
1051         .funcs          = &trace_wake_funcs,
1052 };
1053
1054 /* TRACE_STACK */
1055
1056 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1057                                            int flags, struct trace_event *event)
1058 {
1059         struct stack_entry *field;
1060         struct trace_seq *s = &iter->seq;
1061         unsigned long *p;
1062         unsigned long *end;
1063
1064         trace_assign_type(field, iter->ent);
1065         end = (unsigned long *)((long)iter->ent + iter->ent_size);
1066
1067         trace_seq_puts(s, "<stack trace>\n");
1068
1069         for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1070
1071                 if (trace_seq_has_overflowed(s))
1072                         break;
1073
1074                 trace_seq_puts(s, " => ");
1075                 seq_print_ip_sym(s, *p, flags);
1076                 trace_seq_putc(s, '\n');
1077         }
1078
1079         return trace_handle_return(s);
1080 }
1081
1082 static struct trace_event_functions trace_stack_funcs = {
1083         .trace          = trace_stack_print,
1084 };
1085
1086 static struct trace_event trace_stack_event = {
1087         .type           = TRACE_STACK,
1088         .funcs          = &trace_stack_funcs,
1089 };
1090
1091 /* TRACE_USER_STACK */
1092 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1093                                                 int flags, struct trace_event *event)
1094 {
1095         struct trace_array *tr = iter->tr;
1096         struct userstack_entry *field;
1097         struct trace_seq *s = &iter->seq;
1098         struct mm_struct *mm = NULL;
1099         unsigned int i;
1100
1101         trace_assign_type(field, iter->ent);
1102
1103         trace_seq_puts(s, "<user stack trace>\n");
1104
1105         if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) {
1106                 struct task_struct *task;
1107                 /*
1108                  * we do the lookup on the thread group leader,
1109                  * since individual threads might have already quit!
1110                  */
1111                 rcu_read_lock();
1112                 task = find_task_by_vpid(field->tgid);
1113                 if (task)
1114                         mm = get_task_mm(task);
1115                 rcu_read_unlock();
1116         }
1117
1118         for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
1119                 unsigned long ip = field->caller[i];
1120
1121                 if (ip == ULONG_MAX || trace_seq_has_overflowed(s))
1122                         break;
1123
1124                 trace_seq_puts(s, " => ");
1125
1126                 if (!ip) {
1127                         trace_seq_puts(s, "??");
1128                         trace_seq_putc(s, '\n');
1129                         continue;
1130                 }
1131
1132                 seq_print_user_ip(s, mm, ip, flags);
1133                 trace_seq_putc(s, '\n');
1134         }
1135
1136         if (mm)
1137                 mmput(mm);
1138
1139         return trace_handle_return(s);
1140 }
1141
1142 static struct trace_event_functions trace_user_stack_funcs = {
1143         .trace          = trace_user_stack_print,
1144 };
1145
1146 static struct trace_event trace_user_stack_event = {
1147         .type           = TRACE_USER_STACK,
1148         .funcs          = &trace_user_stack_funcs,
1149 };
1150
1151 /* TRACE_HWLAT */
1152 static enum print_line_t
1153 trace_hwlat_print(struct trace_iterator *iter, int flags,
1154                   struct trace_event *event)
1155 {
1156         struct trace_entry *entry = iter->ent;
1157         struct trace_seq *s = &iter->seq;
1158         struct hwlat_entry *field;
1159
1160         trace_assign_type(field, entry);
1161
1162         trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%ld.%09ld",
1163                          field->seqnum,
1164                          field->duration,
1165                          field->outer_duration,
1166                          field->timestamp.tv_sec,
1167                          field->timestamp.tv_nsec);
1168
1169         if (field->nmi_count) {
1170                 /*
1171                  * The generic sched_clock() is not NMI safe, thus
1172                  * we only record the count and not the time.
1173                  */
1174                 if (!IS_ENABLED(CONFIG_GENERIC_SCHED_CLOCK))
1175                         trace_seq_printf(s, " nmi-total:%llu",
1176                                          field->nmi_total_ts);
1177                 trace_seq_printf(s, " nmi-count:%u",
1178                                  field->nmi_count);
1179         }
1180
1181         trace_seq_putc(s, '\n');
1182
1183         return trace_handle_return(s);
1184 }
1185
1186
1187 static enum print_line_t
1188 trace_hwlat_raw(struct trace_iterator *iter, int flags,
1189                 struct trace_event *event)
1190 {
1191         struct hwlat_entry *field;
1192         struct trace_seq *s = &iter->seq;
1193
1194         trace_assign_type(field, iter->ent);
1195
1196         trace_seq_printf(s, "%llu %lld %ld %09ld %u\n",
1197                          field->duration,
1198                          field->outer_duration,
1199                          field->timestamp.tv_sec,
1200                          field->timestamp.tv_nsec,
1201                          field->seqnum);
1202
1203         return trace_handle_return(s);
1204 }
1205
1206 static struct trace_event_functions trace_hwlat_funcs = {
1207         .trace          = trace_hwlat_print,
1208         .raw            = trace_hwlat_raw,
1209 };
1210
1211 static struct trace_event trace_hwlat_event = {
1212         .type           = TRACE_HWLAT,
1213         .funcs          = &trace_hwlat_funcs,
1214 };
1215
1216 /* TRACE_BPUTS */
1217 static enum print_line_t
1218 trace_bputs_print(struct trace_iterator *iter, int flags,
1219                    struct trace_event *event)
1220 {
1221         struct trace_entry *entry = iter->ent;
1222         struct trace_seq *s = &iter->seq;
1223         struct bputs_entry *field;
1224
1225         trace_assign_type(field, entry);
1226
1227         seq_print_ip_sym(s, field->ip, flags);
1228         trace_seq_puts(s, ": ");
1229         trace_seq_puts(s, field->str);
1230
1231         return trace_handle_return(s);
1232 }
1233
1234
1235 static enum print_line_t
1236 trace_bputs_raw(struct trace_iterator *iter, int flags,
1237                 struct trace_event *event)
1238 {
1239         struct bputs_entry *field;
1240         struct trace_seq *s = &iter->seq;
1241
1242         trace_assign_type(field, iter->ent);
1243
1244         trace_seq_printf(s, ": %lx : ", field->ip);
1245         trace_seq_puts(s, field->str);
1246
1247         return trace_handle_return(s);
1248 }
1249
1250 static struct trace_event_functions trace_bputs_funcs = {
1251         .trace          = trace_bputs_print,
1252         .raw            = trace_bputs_raw,
1253 };
1254
1255 static struct trace_event trace_bputs_event = {
1256         .type           = TRACE_BPUTS,
1257         .funcs          = &trace_bputs_funcs,
1258 };
1259
1260 /* TRACE_BPRINT */
1261 static enum print_line_t
1262 trace_bprint_print(struct trace_iterator *iter, int flags,
1263                    struct trace_event *event)
1264 {
1265         struct trace_entry *entry = iter->ent;
1266         struct trace_seq *s = &iter->seq;
1267         struct bprint_entry *field;
1268
1269         trace_assign_type(field, entry);
1270
1271         seq_print_ip_sym(s, field->ip, flags);
1272         trace_seq_puts(s, ": ");
1273         trace_seq_bprintf(s, field->fmt, field->buf);
1274
1275         return trace_handle_return(s);
1276 }
1277
1278
1279 static enum print_line_t
1280 trace_bprint_raw(struct trace_iterator *iter, int flags,
1281                  struct trace_event *event)
1282 {
1283         struct bprint_entry *field;
1284         struct trace_seq *s = &iter->seq;
1285
1286         trace_assign_type(field, iter->ent);
1287
1288         trace_seq_printf(s, ": %lx : ", field->ip);
1289         trace_seq_bprintf(s, field->fmt, field->buf);
1290
1291         return trace_handle_return(s);
1292 }
1293
1294 static struct trace_event_functions trace_bprint_funcs = {
1295         .trace          = trace_bprint_print,
1296         .raw            = trace_bprint_raw,
1297 };
1298
1299 static struct trace_event trace_bprint_event = {
1300         .type           = TRACE_BPRINT,
1301         .funcs          = &trace_bprint_funcs,
1302 };
1303
1304 /* TRACE_PRINT */
1305 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1306                                            int flags, struct trace_event *event)
1307 {
1308         struct print_entry *field;
1309         struct trace_seq *s = &iter->seq;
1310
1311         trace_assign_type(field, iter->ent);
1312
1313         seq_print_ip_sym(s, field->ip, flags);
1314         trace_seq_printf(s, ": %s", field->buf);
1315
1316         return trace_handle_return(s);
1317 }
1318
1319 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1320                                          struct trace_event *event)
1321 {
1322         struct print_entry *field;
1323
1324         trace_assign_type(field, iter->ent);
1325
1326         trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
1327
1328         return trace_handle_return(&iter->seq);
1329 }
1330
1331 static struct trace_event_functions trace_print_funcs = {
1332         .trace          = trace_print_print,
1333         .raw            = trace_print_raw,
1334 };
1335
1336 static struct trace_event trace_print_event = {
1337         .type           = TRACE_PRINT,
1338         .funcs          = &trace_print_funcs,
1339 };
1340
1341 static enum print_line_t trace_raw_data(struct trace_iterator *iter, int flags,
1342                                          struct trace_event *event)
1343 {
1344         struct raw_data_entry *field;
1345         int i;
1346
1347         trace_assign_type(field, iter->ent);
1348
1349         trace_seq_printf(&iter->seq, "# %x buf:", field->id);
1350
1351         for (i = 0; i < iter->ent_size - offsetof(struct raw_data_entry, buf); i++)
1352                 trace_seq_printf(&iter->seq, " %02x",
1353                                  (unsigned char)field->buf[i]);
1354
1355         trace_seq_putc(&iter->seq, '\n');
1356
1357         return trace_handle_return(&iter->seq);
1358 }
1359
1360 static struct trace_event_functions trace_raw_data_funcs = {
1361         .trace          = trace_raw_data,
1362         .raw            = trace_raw_data,
1363 };
1364
1365 static struct trace_event trace_raw_data_event = {
1366         .type           = TRACE_RAW_DATA,
1367         .funcs          = &trace_raw_data_funcs,
1368 };
1369
1370
1371 static struct trace_event *events[] __initdata = {
1372         &trace_fn_event,
1373         &trace_ctx_event,
1374         &trace_wake_event,
1375         &trace_stack_event,
1376         &trace_user_stack_event,
1377         &trace_bputs_event,
1378         &trace_bprint_event,
1379         &trace_print_event,
1380         &trace_hwlat_event,
1381         &trace_raw_data_event,
1382         NULL
1383 };
1384
1385 __init static int init_events(void)
1386 {
1387         struct trace_event *event;
1388         int i, ret;
1389
1390         for (i = 0; events[i]; i++) {
1391                 event = events[i];
1392
1393                 ret = register_trace_event(event);
1394                 if (!ret) {
1395                         printk(KERN_WARNING "event %d failed to register\n",
1396                                event->type);
1397                         WARN_ON_ONCE(1);
1398                 }
1399         }
1400
1401         return 0;
1402 }
1403 early_initcall(init_events);