kernel/trace/trace_events.c

   1 /*
   2  * event tracer
   3  *
   4  * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
   5  *
   6  *  - Added format output of fields of the trace point.
   7  *    This was based off of work by Tom Zanussi <tzanussi@gmail.com>.
   8  *
   9  */
  10
  11 #include <linux/workqueue.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/kthread.h>
  14 #include <linux/debugfs.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/module.h>
  17 #include <linux/ctype.h>
  18 #include <linux/slab.h>
  19 #include <linux/delay.h>
  20
  21 #include <asm/setup.h>
  22
  23 #include "trace_output.h"
  24
  25 #undef TRACE_SYSTEM
  26 #define TRACE_SYSTEM "TRACE_SYSTEM"
  27
  28 DEFINE_MUTEX(event_mutex);
  29
  30 LIST_HEAD(ftrace_events);
  31 LIST_HEAD(ftrace_common_fields);
  32
  33 struct list_head *
  34 trace_get_fields(struct ftrace_event_call *event_call)
  35 {
  36         if (!event_call->class->get_fields)
  37                 return &event_call->class->fields;
  38         return event_call->class->get_fields(event_call);
  39 }
  40
  41 static int __trace_define_field(struct list_head *head, const char *type,
  42                                 const char *name, int offset, int size,
  43                                 int is_signed, int filter_type)
  44 {
  45         struct ftrace_event_field *field;
  46
  47         field = kzalloc(sizeof(*field), GFP_KERNEL);
  48         if (!field)
  49                 goto err;
  50
  51         field->name = kstrdup(name, GFP_KERNEL);
  52         if (!field->name)
  53                 goto err;
  54
  55         field->type = kstrdup(type, GFP_KERNEL);
  56         if (!field->type)
  57                 goto err;
  58
  59         if (filter_type == FILTER_OTHER)
  60                 field->filter_type = filter_assign_type(type);
  61         else
  62                 field->filter_type = filter_type;
  63
  64         field->offset = offset;
  65         field->size = size;
  66         field->is_signed = is_signed;
  67
  68         list_add(&field->link, head);
  69
  70         return 0;
  71
  72 err:
  73         if (field)
  74                 kfree(field->name);
  75         kfree(field);
  76
  77         return -ENOMEM;
  78 }
  79
  80 int trace_define_field(struct ftrace_event_call *call, const char *type,
  81                        const char *name, int offset, int size, int is_signed,
  82                        int filter_type)
  83 {
  84         struct list_head *head;
  85
  86         if (WARN_ON(!call->class))
  87                 return 0;
  88
  89         head = trace_get_fields(call);
  90         return __trace_define_field(head, type, name, offset, size,
  91                                     is_signed, filter_type);
  92 }
  93 EXPORT_SYMBOL_GPL(trace_define_field);
  94
  95 #define __common_field(type, item)                                      \
  96         ret = __trace_define_field(&ftrace_common_fields, #type,        \
  97                                    "common_" #item,                     \
  98                                    offsetof(typeof(ent), item),         \
  99                                    sizeof(ent.item),                    \
 100                                    is_signed_type(type), FILTER_OTHER); \
 101         if (ret)                                                        \
 102                 return ret;
 103
 104 static int trace_define_common_fields(void)
 105 {
 106         int ret;
 107         struct trace_entry ent;
 108
 109         __common_field(unsigned short, type);
 110         __common_field(unsigned char, flags);
 111         __common_field(unsigned char, preempt_count);
 112         __common_field(int, pid);
 113         __common_field(int, lock_depth);
 114
 115         return ret;
 116 }
 117
 118 void trace_destroy_fields(struct ftrace_event_call *call)
 119 {
 120         struct ftrace_event_field *field, *next;
 121         struct list_head *head;
 122
 123         head = trace_get_fields(call);
 124         list_for_each_entry_safe(field, next, head, link) {
 125                 list_del(&field->link);
 126                 kfree(field->type);
 127                 kfree(field->name);
 128                 kfree(field);
 129         }
 130 }
 131
 132 int trace_event_raw_init(struct ftrace_event_call *call)
 133 {
 134         int id;
 135
 136         id = register_ftrace_event(&call->event);
 137         if (!id)
 138                 return -ENODEV;
 139
 140         return 0;
 141 }
 142 EXPORT_SYMBOL_GPL(trace_event_raw_init);
 143
 144 int ftrace_event_reg(struct ftrace_event_call *call, enum trace_reg type)
 145 {
 146         switch (type) {
 147         case TRACE_REG_REGISTER:
 148                 return tracepoint_probe_register(call->name,
 149                                                  call->class->probe,
 150                                                  call);
 151         case TRACE_REG_UNREGISTER:
 152                 tracepoint_probe_unregister(call->name,
 153                                             call->class->probe,
 154                                             call);
 155                 return 0;
 156
 157 #ifdef CONFIG_PERF_EVENTS
 158         case TRACE_REG_PERF_REGISTER:
 159                 return tracepoint_probe_register(call->name,
 160                                                  call->class->perf_probe,
 161                                                  call);
 162         case TRACE_REG_PERF_UNREGISTER:
 163                 tracepoint_probe_unregister(call->name,
 164                                             call->class->perf_probe,
 165                                             call);
 166                 return 0;
 167 #endif
 168         }
 169         return 0;
 170 }
 171 EXPORT_SYMBOL_GPL(ftrace_event_reg);
 172
 173 void trace_event_enable_cmd_record(bool enable)
 174 {
 175         struct ftrace_event_call *call;
 176
 177         mutex_lock(&event_mutex);
 178         list_for_each_entry(call, &ftrace_events, list) {
 179                 if (!(call->flags & TRACE_EVENT_FL_ENABLED))
 180                         continue;
 181
 182                 if (enable) {
 183                         tracing_start_cmdline_record();
 184                         call->flags |= TRACE_EVENT_FL_RECORDED_CMD;
 185                 } else {
 186                         tracing_stop_cmdline_record();
 187                         call->flags &= ~TRACE_EVENT_FL_RECORDED_CMD;
 188                 }
 189         }
 190         mutex_unlock(&event_mutex);
 191 }
 192
 193 static int ftrace_event_enable_disable(struct ftrace_event_call *call,
 194                                         int enable)
 195 {
 196         int ret = 0;
 197
 198         switch (enable) {
 199         case 0:
 200                 if (call->flags & TRACE_EVENT_FL_ENABLED) {
 201                         call->flags &= ~TRACE_EVENT_FL_ENABLED;
 202                         if (call->flags & TRACE_EVENT_FL_RECORDED_CMD) {
 203                                 tracing_stop_cmdline_record();
 204                                 call->flags &= ~TRACE_EVENT_FL_RECORDED_CMD;
 205                         }
 206                         call->class->reg(call, TRACE_REG_UNREGISTER);
 207                 }
 208                 break;
 209         case 1:
 210                 if (!(call->flags & TRACE_EVENT_FL_ENABLED)) {
 211                         if (trace_flags & TRACE_ITER_RECORD_CMD) {
 212                                 tracing_start_cmdline_record();
 213                                 call->flags |= TRACE_EVENT_FL_RECORDED_CMD;
 214                         }
 215                         ret = call->class->reg(call, TRACE_REG_REGISTER);
 216                         if (ret) {
 217                                 tracing_stop_cmdline_record();
 218                                 pr_info("event trace: Could not enable event "
 219                                         "%s\n", call->name);
 220                                 break;
 221                         }
 222                         call->flags |= TRACE_EVENT_FL_ENABLED;
 223                 }
 224                 break;
 225         }
 226
 227         return ret;
 228 }
 229
 230 static void ftrace_clear_events(void)
 231 {
 232         struct ftrace_event_call *call;
 233
 234         mutex_lock(&event_mutex);
 235         list_for_each_entry(call, &ftrace_events, list) {
 236                 ftrace_event_enable_disable(call, 0);
 237         }
 238         mutex_unlock(&event_mutex);
 239 }
 240
 241 /*
 242  * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events.
 243  */
 244 static int __ftrace_set_clr_event(const char *match, const char *sub,
 245                                   const char *event, int set)
 246 {
 247         struct ftrace_event_call *call;
 248         int ret = -EINVAL;
 249
 250         mutex_lock(&event_mutex);
 251         list_for_each_entry(call, &ftrace_events, list) {
 252
 253                 if (!call->name || !call->class || !call->class->reg)
 254                         continue;
 255
 256                 if (match &&
 257                     strcmp(match, call->name) != 0 &&
 258                     strcmp(match, call->class->system) != 0)
 259                         continue;
 260
 261                 if (sub && strcmp(sub, call->class->system) != 0)
 262                         continue;
 263
 264                 if (event && strcmp(event, call->name) != 0)
 265                         continue;
 266
 267                 ftrace_event_enable_disable(call, set);
 268
 269                 ret = 0;
 270         }
 271         mutex_unlock(&event_mutex);
 272
 273         return ret;
 274 }
 275
 276 static int ftrace_set_clr_event(char *buf, int set)
 277 {
 278         char *event = NULL, *sub = NULL, *match;
 279
 280         /*
 281          * The buf format can be <subsystem>:<event-name>
 282          *  *:<event-name> means any event by that name.
 283          *  :<event-name> is the same.
 284          *
 285          *  <subsystem>:* means all events in that subsystem
 286          *  <subsystem>: means the same.
 287          *
 288          *  <name> (no ':') means all events in a subsystem with
 289          *  the name <name> or any event that matches <name>
 290          */
 291
 292         match = strsep(&buf, ":");
 293         if (buf) {
 294                 sub = match;
 295                 event = buf;
 296                 match = NULL;
 297
 298                 if (!strlen(sub) || strcmp(sub, "*") == 0)
 299                         sub = NULL;
 300                 if (!strlen(event) || strcmp(event, "*") == 0)
 301                         event = NULL;
 302         }
 303
 304         return __ftrace_set_clr_event(match, sub, event, set);
 305 }
 306
 307 /**
 308  * trace_set_clr_event - enable or disable an event
 309  * @system: system name to match (NULL for any system)
 310  * @event: event name to match (NULL for all events, within system)
 311  * @set: 1 to enable, 0 to disable
 312  *
 313  * This is a way for other parts of the kernel to enable or disable
 314  * event recording.
 315  *
 316  * Returns 0 on success, -EINVAL if the parameters do not match any
 317  * registered events.
 318  */
 319 int trace_set_clr_event(const char *system, const char *event, int set)
 320 {
 321         return __ftrace_set_clr_event(NULL, system, event, set);
 322 }
 323
 324 /* 128 should be much more than enough */
 325 #define EVENT_BUF_SIZE          127
 326
 327 static ssize_t
 328 ftrace_event_write(struct file *file, const char __user *ubuf,
 329                    size_t cnt, loff_t *ppos)
 330 {
 331         struct trace_parser parser;
 332         ssize_t read, ret;
 333
 334         if (!cnt)
 335                 return 0;
 336
 337         ret = tracing_update_buffers();
 338         if (ret < 0)
 339                 return ret;
 340
 341         if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
 342                 return -ENOMEM;
 343
 344         read = trace_get_user(&parser, ubuf, cnt, ppos);
 345
 346         if (read >= 0 && trace_parser_loaded((&parser))) {
 347                 int set = 1;
 348
 349                 if (*parser.buffer == '!')
 350                         set = 0;
 351
 352                 parser.buffer[parser.idx] = 0;
 353
 354                 ret = ftrace_set_clr_event(parser.buffer + !set, set);
 355                 if (ret)
 356                         goto out_put;
 357         }
 358
 359         ret = read;
 360
 361  out_put:
 362         trace_parser_put(&parser);
 363
 364         return ret;
 365 }
 366
 367 static void *
 368 t_next(struct seq_file *m, void *v, loff_t *pos)
 369 {
 370         struct ftrace_event_call *call = v;
 371
 372         (*pos)++;
 373
 374         list_for_each_entry_continue(call, &ftrace_events, list) {
 375                 /*
 376                  * The ftrace subsystem is for showing formats only.
 377                  * They can not be enabled or disabled via the event files.
 378                  */
 379                 if (call->class && call->class->reg)
 380                         return call;
 381         }
 382
 383         return NULL;
 384 }
 385
 386 static void *t_start(struct seq_file *m, loff_t *pos)
 387 {
 388         struct ftrace_event_call *call;
 389         loff_t l;
 390
 391         mutex_lock(&event_mutex);
 392
 393         call = list_entry(&ftrace_events, struct ftrace_event_call, list);
 394         for (l = 0; l <= *pos; ) {
 395                 call = t_next(m, call, &l);
 396                 if (!call)
 397                         break;
 398         }
 399         return call;
 400 }
 401
 402 static void *
 403 s_next(struct seq_file *m, void *v, loff_t *pos)
 404 {
 405         struct ftrace_event_call *call = v;
 406
 407         (*pos)++;
 408
 409         list_for_each_entry_continue(call, &ftrace_events, list) {
 410                 if (call->flags & TRACE_EVENT_FL_ENABLED)
 411                         return call;
 412         }
 413
 414         return NULL;
 415 }
 416
 417 static void *s_start(struct seq_file *m, loff_t *pos)
 418 {
 419         struct ftrace_event_call *call;
 420         loff_t l;
 421
 422         mutex_lock(&event_mutex);
 423
 424         call = list_entry(&ftrace_events, struct ftrace_event_call, list);
 425         for (l = 0; l <= *pos; ) {
 426                 call = s_next(m, call, &l);
 427                 if (!call)
 428                         break;
 429         }
 430         return call;
 431 }
 432
 433 static int t_show(struct seq_file *m, void *v)
 434 {
 435         struct ftrace_event_call *call = v;
 436
 437         if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
 438                 seq_printf(m, "%s:", call->class->system);
 439         seq_printf(m, "%s\n", call->name);
 440
 441         return 0;
 442 }
 443
 444 static void t_stop(struct seq_file *m, void *p)
 445 {
 446         mutex_unlock(&event_mutex);
 447 }
 448
 449 static int
 450 ftrace_event_seq_open(struct inode *inode, struct file *file)
 451 {
 452         const struct seq_operations *seq_ops;
 453
 454         if ((file->f_mode & FMODE_WRITE) &&
 455             (file->f_flags & O_TRUNC))
 456                 ftrace_clear_events();
 457
 458         seq_ops = inode->i_private;
 459         return seq_open(file, seq_ops);
 460 }
 461
 462 static ssize_t
 463 event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
 464                   loff_t *ppos)
 465 {
 466         struct ftrace_event_call *call = filp->private_data;
 467         char *buf;
 468
 469         if (call->flags & TRACE_EVENT_FL_ENABLED)
 470                 buf = "1\n";
 471         else
 472                 buf = "0\n";
 473
 474         return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
 475 }
 476
 477 static ssize_t
 478 event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
 479                    loff_t *ppos)
 480 {
 481         struct ftrace_event_call *call = filp->private_data;
 482         char buf[64];
 483         unsigned long val;
 484         int ret;
 485
 486         if (cnt >= sizeof(buf))
 487                 return -EINVAL;
 488
 489         if (copy_from_user(&buf, ubuf, cnt))
 490                 return -EFAULT;
 491
 492         buf[cnt] = 0;
 493
 494         ret = strict_strtoul(buf, 10, &val);
 495         if (ret < 0)
 496                 return ret;
 497
 498         ret = tracing_update_buffers();
 499         if (ret < 0)
 500                 return ret;
 501
 502         switch (val) {
 503         case 0:
 504         case 1:
 505                 mutex_lock(&event_mutex);
 506                 ret = ftrace_event_enable_disable(call, val);
 507                 mutex_unlock(&event_mutex);
 508                 break;
 509
 510         default:
 511                 return -EINVAL;
 512         }
 513
 514         *ppos += cnt;
 515
 516         return ret ? ret : cnt;
 517 }
 518
 519 static ssize_t
 520 system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
 521                    loff_t *ppos)
 522 {
 523         const char set_to_char[4] = { '?', '0', '1', 'X' };
 524         const char *system = filp->private_data;
 525         struct ftrace_event_call *call;
 526         char buf[2];
 527         int set = 0;
 528         int ret;
 529
 530         mutex_lock(&event_mutex);
 531         list_for_each_entry(call, &ftrace_events, list) {
 532                 if (!call->name || !call->class || !call->class->reg)
 533                         continue;
 534
 535                 if (system && strcmp(call->class->system, system) != 0)
 536                         continue;
 537
 538                 /*
 539                  * We need to find out if all the events are set
 540                  * or if all events or cleared, or if we have
 541                  * a mixture.
 542                  */
 543                 set |= (1 << !!(call->flags & TRACE_EVENT_FL_ENABLED));
 544
 545                 /*
 546                  * If we have a mixture, no need to look further.
 547                  */
 548                 if (set == 3)
 549                         break;
 550         }
 551         mutex_unlock(&event_mutex);
 552
 553         buf[0] = set_to_char[set];
 554         buf[1] = '\n';
 555
 556         ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
 557
 558         return ret;
 559 }
 560
 561 static ssize_t
 562 system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
 563                     loff_t *ppos)
 564 {
 565         const char *system = filp->private_data;
 566         unsigned long val;
 567         char buf[64];
 568         ssize_t ret;
 569
 570         if (cnt >= sizeof(buf))
 571                 return -EINVAL;
 572
 573         if (copy_from_user(&buf, ubuf, cnt))
 574                 return -EFAULT;
 575
 576         buf[cnt] = 0;
 577
 578         ret = strict_strtoul(buf, 10, &val);
 579         if (ret < 0)
 580                 return ret;
 581
 582         ret = tracing_update_buffers();
 583         if (ret < 0)
 584                 return ret;
 585
 586         if (val != 0 && val != 1)
 587                 return -EINVAL;
 588
 589         ret = __ftrace_set_clr_event(NULL, system, NULL, val);
 590         if (ret)
 591                 goto out;
 592
 593         ret = cnt;
 594
 595 out:
 596         *ppos += cnt;
 597
 598         return ret;
 599 }
 600
 601 static void print_event_fields(struct trace_seq *s, struct list_head *head)
 602 {
 603         struct ftrace_event_field *field;
 604
 605         list_for_each_entry_reverse(field, head, link) {
 606                 /*
 607                  * Smartly shows the array type(except dynamic array).
 608                  * Normal:
 609                  *      field:TYPE VAR
 610                  * If TYPE := TYPE[LEN], it is shown:
 611                  *      field:TYPE VAR[LEN]
 612                  */
 613                 const char *array_descriptor = strchr(field->type, '[');
 614
 615                 if (!strncmp(field->type, "__data_loc", 10))
 616                         array_descriptor = NULL;
 617
 618                 if (!array_descriptor) {
 619                         trace_seq_printf(s, "\tfield:%s %s;\toffset:%u;"
 620                                         "\tsize:%u;\tsigned:%d;\n",
 621                                         field->type, field->name, field->offset,
 622                                         field->size, !!field->is_signed);
 623                 } else {
 624                         trace_seq_printf(s, "\tfield:%.*s %s%s;\toffset:%u;"
 625                                         "\tsize:%u;\tsigned:%d;\n",
 626                                         (int)(array_descriptor - field->type),
 627                                         field->type, field->name,
 628                                         array_descriptor, field->offset,
 629                                         field->size, !!field->is_signed);
 630                 }
 631         }
 632 }
 633
 634 static ssize_t
 635 event_format_read(struct file *filp, char __user *ubuf, size_t cnt,
 636                   loff_t *ppos)
 637 {
 638         struct ftrace_event_call *call = filp->private_data;
 639         struct list_head *head;
 640         struct trace_seq *s;
 641         char *buf;
 642         int r;
 643
 644         if (*ppos)
 645                 return 0;
 646
 647         s = kmalloc(sizeof(*s), GFP_KERNEL);
 648         if (!s)
 649                 return -ENOMEM;
 650
 651         trace_seq_init(s);
 652
 653         trace_seq_printf(s, "name: %s\n", call->name);
 654         trace_seq_printf(s, "ID: %d\n", call->event.type);
 655         trace_seq_printf(s, "format:\n");
 656
 657         /* print common fields */
 658         print_event_fields(s, &ftrace_common_fields);
 659
 660         trace_seq_putc(s, '\n');
 661
 662         /* print event specific fields */
 663         head = trace_get_fields(call);
 664         print_event_fields(s, head);
 665
 666         r = trace_seq_printf(s, "\nprint fmt: %s\n", call->print_fmt);
 667
 668         if (!r) {
 669                 /*
 670                  * ug!  The format output is bigger than a PAGE!!
 671                  */
 672                 buf = "FORMAT TOO BIG\n";
 673                 r = simple_read_from_buffer(ubuf, cnt, ppos,
 674                                               buf, strlen(buf));
 675                 goto out;
 676         }
 677
 678         r = simple_read_from_buffer(ubuf, cnt, ppos,
 679                                     s->buffer, s->len);
 680  out:
 681         kfree(s);
 682         return r;
 683 }
 684
 685 static ssize_t
 686 event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
 687 {
 688         struct ftrace_event_call *call = filp->private_data;
 689         struct trace_seq *s;
 690         int r;
 691
 692         if (*ppos)
 693                 return 0;
 694
 695         s = kmalloc(sizeof(*s), GFP_KERNEL);
 696         if (!s)
 697                 return -ENOMEM;
 698
 699         trace_seq_init(s);
 700         trace_seq_printf(s, "%d\n", call->event.type);
 701
 702         r = simple_read_from_buffer(ubuf, cnt, ppos,
 703                                     s->buffer, s->len);
 704         kfree(s);
 705         return r;
 706 }
 707
 708 static ssize_t
 709 event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
 710                   loff_t *ppos)
 711 {
 712         struct ftrace_event_call *call = filp->private_data;
 713         struct trace_seq *s;
 714         int r;
 715
 716         if (*ppos)
 717                 return 0;
 718
 719         s = kmalloc(sizeof(*s), GFP_KERNEL);
 720         if (!s)
 721                 return -ENOMEM;
 722
 723         trace_seq_init(s);
 724
 725         print_event_filter(call, s);
 726         r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
 727
 728         kfree(s);
 729
 730         return r;
 731 }
 732
 733 static ssize_t
 734 event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
 735                    loff_t *ppos)
 736 {
 737         struct ftrace_event_call *call = filp->private_data;
 738         char *buf;
 739         int err;
 740
 741         if (cnt >= PAGE_SIZE)
 742                 return -EINVAL;
 743
 744         buf = (char *)__get_free_page(GFP_TEMPORARY);
 745         if (!buf)
 746                 return -ENOMEM;
 747
 748         if (copy_from_user(buf, ubuf, cnt)) {
 749                 free_page((unsigned long) buf);
 750                 return -EFAULT;
 751         }
 752         buf[cnt] = '\0';
 753
 754         err = apply_event_filter(call, buf);
 755         free_page((unsigned long) buf);
 756         if (err < 0)
 757                 return err;
 758
 759         *ppos += cnt;
 760
 761         return cnt;
 762 }
 763
 764 static ssize_t
 765 subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
 766                       loff_t *ppos)
 767 {
 768         struct event_subsystem *system = filp->private_data;
 769         struct trace_seq *s;
 770         int r;
 771
 772         if (*ppos)
 773                 return 0;
 774
 775         s = kmalloc(sizeof(*s), GFP_KERNEL);
 776         if (!s)
 777                 return -ENOMEM;
 778
 779         trace_seq_init(s);
 780
 781         print_subsystem_event_filter(system, s);
 782         r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
 783
 784         kfree(s);
 785
 786         return r;
 787 }
 788
 789 static ssize_t
 790 subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
 791                        loff_t *ppos)
 792 {
 793         struct event_subsystem *system = filp->private_data;
 794         char *buf;
 795         int err;
 796
 797         if (cnt >= PAGE_SIZE)
 798                 return -EINVAL;
 799
 800         buf = (char *)__get_free_page(GFP_TEMPORARY);
 801         if (!buf)
 802                 return -ENOMEM;
 803
 804         if (copy_from_user(buf, ubuf, cnt)) {
 805                 free_page((unsigned long) buf);
 806                 return -EFAULT;
 807         }
 808         buf[cnt] = '\0';
 809
 810         err = apply_subsystem_event_filter(system, buf);
 811         free_page((unsigned long) buf);
 812         if (err < 0)
 813                 return err;
 814
 815         *ppos += cnt;
 816
 817         return cnt;
 818 }
 819
 820 static ssize_t
 821 show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
 822 {
 823         int (*func)(struct trace_seq *s) = filp->private_data;
 824         struct trace_seq *s;
 825         int r;
 826
 827         if (*ppos)
 828                 return 0;
 829
 830         s = kmalloc(sizeof(*s), GFP_KERNEL);
 831         if (!s)
 832                 return -ENOMEM;
 833
 834         trace_seq_init(s);
 835
 836         func(s);
 837         r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
 838
 839         kfree(s);
 840
 841         return r;
 842 }
 843
 844 static const struct seq_operations show_event_seq_ops = {
 845         .start = t_start,
 846         .next = t_next,
 847         .show = t_show,
 848         .stop = t_stop,
 849 };
 850
 851 static const struct seq_operations show_set_event_seq_ops = {
 852         .start = s_start,
 853         .next = s_next,
 854         .show = t_show,
 855         .stop = t_stop,
 856 };
 857
 858 static const struct file_operations ftrace_avail_fops = {
 859         .open = ftrace_event_seq_open,
 860         .read = seq_read,
 861         .llseek = seq_lseek,
 862         .release = seq_release,
 863 };
 864
 865 static const struct file_operations ftrace_set_event_fops = {
 866         .open = ftrace_event_seq_open,
 867         .read = seq_read,
 868         .write = ftrace_event_write,
 869         .llseek = seq_lseek,
 870         .release = seq_release,
 871 };
 872
 873 static const struct file_operations ftrace_enable_fops = {
 874         .open = tracing_open_generic,
 875         .read = event_enable_read,
 876         .write = event_enable_write,
 877 };
 878
 879 static const struct file_operations ftrace_event_format_fops = {
 880         .open = tracing_open_generic,
 881         .read = event_format_read,
 882 };
 883
 884 static const struct file_operations ftrace_event_id_fops = {
 885         .open = tracing_open_generic,
 886         .read = event_id_read,
 887 };
 888
 889 static const struct file_operations ftrace_event_filter_fops = {
 890         .open = tracing_open_generic,
 891         .read = event_filter_read,
 892         .write = event_filter_write,
 893 };
 894
 895 static const struct file_operations ftrace_subsystem_filter_fops = {
 896         .open = tracing_open_generic,
 897         .read = subsystem_filter_read,
 898         .write = subsystem_filter_write,
 899 };
 900
 901 static const struct file_operations ftrace_system_enable_fops = {
 902         .open = tracing_open_generic,
 903         .read = system_enable_read,
 904         .write = system_enable_write,
 905 };
 906
 907 static const struct file_operations ftrace_show_header_fops = {
 908         .open = tracing_open_generic,
 909         .read = show_header,
 910 };
 911
 912 static struct dentry *event_trace_events_dir(void)
 913 {
 914         static struct dentry *d_tracer;
 915         static struct dentry *d_events;
 916
 917         if (d_events)
 918                 return d_events;
 919
 920         d_tracer = tracing_init_dentry();
 921         if (!d_tracer)
 922                 return NULL;
 923
 924         d_events = debugfs_create_dir("events", d_tracer);
 925         if (!d_events)
 926                 pr_warning("Could not create debugfs "
 927                            "'events' directory\n");
 928
 929         return d_events;
 930 }
 931
 932 static LIST_HEAD(event_subsystems);
 933
 934 static struct dentry *
 935 event_subsystem_dir(const char *name, struct dentry *d_events)
 936 {
 937         struct event_subsystem *system;
 938         struct dentry *entry;
 939
 940         /* First see if we did not already create this dir */
 941         list_for_each_entry(system, &event_subsystems, list) {
 942                 if (strcmp(system->name, name) == 0) {
 943                         system->nr_events++;
 944                         return system->entry;
 945                 }
 946         }
 947
 948         /* need to create new entry */
 949         system = kmalloc(sizeof(*system), GFP_KERNEL);
 950         if (!system) {
 951                 pr_warning("No memory to create event subsystem %s\n",
 952                            name);
 953                 return d_events;
 954         }
 955
 956         system->entry = debugfs_create_dir(name, d_events);
 957         if (!system->entry) {
 958                 pr_warning("Could not create event subsystem %s\n",
 959                            name);
 960                 kfree(system);
 961                 return d_events;
 962         }
 963
 964         system->nr_events = 1;
 965         system->name = kstrdup(name, GFP_KERNEL);
 966         if (!system->name) {
 967                 debugfs_remove(system->entry);
 968                 kfree(system);
 969                 return d_events;
 970         }
 971
 972         list_add(&system->list, &event_subsystems);
 973
 974         system->filter = NULL;
 975
 976         system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL);
 977         if (!system->filter) {
 978                 pr_warning("Could not allocate filter for subsystem "
 979                            "'%s'\n", name);
 980                 return system->entry;
 981         }
 982
 983         entry = debugfs_create_file("filter", 0644, system->entry, system,
 984                                     &ftrace_subsystem_filter_fops);
 985         if (!entry) {
 986                 kfree(system->filter);
 987                 system->filter = NULL;
 988                 pr_warning("Could not create debugfs "
 989                            "'%s/filter' entry\n", name);
 990         }
 991
 992         trace_create_file("enable", 0644, system->entry,
 993                           (void *)system->name,
 994                           &ftrace_system_enable_fops);
 995
 996         return system->entry;
 997 }
 998
 999 static int
1000 event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
1001                  const struct file_operations *id,
1002                  const struct file_operations *enable,
1003                  const struct file_operations *filter,
1004                  const struct file_operations *format)
1005 {
1006         struct list_head *head;
1007         int ret;
1008
1009         /*
1010          * If the trace point header did not define TRACE_SYSTEM
1011          * then the system would be called "TRACE_SYSTEM".
1012          */
1013         if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
1014                 d_events = event_subsystem_dir(call->class->system, d_events);
1015
1016         call->dir = debugfs_create_dir(call->name, d_events);
1017         if (!call->dir) {
1018                 pr_warning("Could not create debugfs "
1019                            "'%s' directory\n", call->name);
1020                 return -1;
1021         }
1022
1023         if (call->class->reg)
1024                 trace_create_file("enable", 0644, call->dir, call,
1025                                   enable);
1026
1027 #ifdef CONFIG_PERF_EVENTS
1028         if (call->event.type && call->class->reg)
1029                 trace_create_file("id", 0444, call->dir, call,
1030                                   id);
1031 #endif
1032
1033         /*
1034          * Other events may have the same class. Only update
1035          * the fields if they are not already defined.
1036          */
1037         head = trace_get_fields(call);
1038         if (list_empty(head)) {
1039                 ret = call->class->define_fields(call);
1040                 if (ret < 0) {
1041                         pr_warning("Could not initialize trace point"
1042                                    " events/%s\n", call->name);
1043                         return ret;
1044                 }
1045         }
1046         trace_create_file("filter", 0644, call->dir, call,
1047                           filter);
1048
1049         trace_create_file("format", 0444, call->dir, call,
1050                           format);
1051
1052         return 0;
1053 }
1054
1055 static int
1056 __trace_add_event_call(struct ftrace_event_call *call, struct module *mod,
1057                        const struct file_operations *id,
1058                        const struct file_operations *enable,
1059                        const struct file_operations *filter,
1060                        const struct file_operations *format)
1061 {
1062         struct dentry *d_events;
1063         int ret;
1064
1065         /* The linker may leave blanks */
1066         if (!call->name)
1067                 return -EINVAL;
1068
1069         if (call->class->raw_init) {
1070                 ret = call->class->raw_init(call);
1071                 if (ret < 0) {
1072                         if (ret != -ENOSYS)
1073                                 pr_warning("Could not initialize trace events/%s\n",
1074                                            call->name);
1075                         return ret;
1076                 }
1077         }
1078
1079         d_events = event_trace_events_dir();
1080         if (!d_events)
1081                 return -ENOENT;
1082
1083         ret = event_create_dir(call, d_events, id, enable, filter, format);
1084         if (!ret)
1085                 list_add(&call->list, &ftrace_events);
1086         call->mod = mod;
1087
1088         return ret;
1089 }
1090
1091 /* Add an additional event_call dynamically */
1092 int trace_add_event_call(struct ftrace_event_call *call)
1093 {
1094         int ret;
1095         mutex_lock(&event_mutex);
1096         ret = __trace_add_event_call(call, NULL, &ftrace_event_id_fops,
1097                                      &ftrace_enable_fops,
1098                                      &ftrace_event_filter_fops,
1099                                      &ftrace_event_format_fops);
1100         mutex_unlock(&event_mutex);
1101         return ret;
1102 }
1103
1104 static void remove_subsystem_dir(const char *name)
1105 {
1106         struct event_subsystem *system;
1107
1108         if (strcmp(name, TRACE_SYSTEM) == 0)
1109                 return;
1110
1111         list_for_each_entry(system, &event_subsystems, list) {
1112                 if (strcmp(system->name, name) == 0) {
1113                         if (!--system->nr_events) {
1114                                 struct event_filter *filter = system->filter;
1115
1116                                 debugfs_remove_recursive(system->entry);
1117                                 list_del(&system->list);
1118                                 if (filter) {
1119                                         kfree(filter->filter_string);
1120                                         kfree(filter);
1121                                 }
1122                                 kfree(system->name);
1123                                 kfree(system);
1124                         }
1125                         break;
1126                 }
1127         }
1128 }
1129
1130 /*
1131  * Must be called under locking both of event_mutex and trace_event_mutex.
1132  */
1133 static void __trace_remove_event_call(struct ftrace_event_call *call)
1134 {
1135         ftrace_event_enable_disable(call, 0);
1136         if (call->event.funcs)
1137                 __unregister_ftrace_event(&call->event);
1138         debugfs_remove_recursive(call->dir);
1139         list_del(&call->list);
1140         trace_destroy_fields(call);
1141         destroy_preds(call);
1142         remove_subsystem_dir(call->class->system);
1143 }
1144
1145 /* Remove an event_call */
1146 void trace_remove_event_call(struct ftrace_event_call *call)
1147 {
1148         mutex_lock(&event_mutex);
1149         down_write(&trace_event_mutex);
1150         __trace_remove_event_call(call);
1151         up_write(&trace_event_mutex);
1152         mutex_unlock(&event_mutex);
1153 }
1154
1155 #define for_each_event(event, start, end)                       \
1156         for (event = start;                                     \
1157              (unsigned long)event < (unsigned long)end;         \
1158              event++)
1159
1160 #ifdef CONFIG_MODULES
1161
1162 static LIST_HEAD(ftrace_module_file_list);
1163
1164 /*
1165  * Modules must own their file_operations to keep up with
1166  * reference counting.
1167  */
1168 struct ftrace_module_file_ops {
1169         struct list_head                list;
1170         struct module                   *mod;
1171         struct file_operations          id;
1172         struct file_operations          enable;
1173         struct file_operations          format;
1174         struct file_operations          filter;
1175 };
1176
1177 static struct ftrace_module_file_ops *
1178 trace_create_file_ops(struct module *mod)
1179 {
1180         struct ftrace_module_file_ops *file_ops;
1181
1182         /*
1183          * This is a bit of a PITA. To allow for correct reference
1184          * counting, modules must "own" their file_operations.
1185          * To do this, we allocate the file operations that will be
1186          * used in the event directory.
1187          */
1188
1189         file_ops = kmalloc(sizeof(*file_ops), GFP_KERNEL);
1190         if (!file_ops)
1191                 return NULL;
1192
1193         file_ops->mod = mod;
1194
1195         file_ops->id = ftrace_event_id_fops;
1196         file_ops->id.owner = mod;
1197
1198         file_ops->enable = ftrace_enable_fops;
1199         file_ops->enable.owner = mod;
1200
1201         file_ops->filter = ftrace_event_filter_fops;
1202         file_ops->filter.owner = mod;
1203
1204         file_ops->format = ftrace_event_format_fops;
1205         file_ops->format.owner = mod;
1206
1207         list_add(&file_ops->list, &ftrace_module_file_list);
1208
1209         return file_ops;
1210 }
1211
1212 static void trace_module_add_events(struct module *mod)
1213 {
1214         struct ftrace_module_file_ops *file_ops = NULL;
1215         struct ftrace_event_call *call, *start, *end;
1216
1217         start = mod->trace_events;
1218         end = mod->trace_events + mod->num_trace_events;
1219
1220         if (start == end)
1221                 return;
1222
1223         file_ops = trace_create_file_ops(mod);
1224         if (!file_ops)
1225                 return;
1226
1227         for_each_event(call, start, end) {
1228                 __trace_add_event_call(call, mod,
1229                                        &file_ops->id, &file_ops->enable,
1230                                        &file_ops->filter, &file_ops->format);
1231         }
1232 }
1233
1234 static void trace_module_remove_events(struct module *mod)
1235 {
1236         struct ftrace_module_file_ops *file_ops;
1237         struct ftrace_event_call *call, *p;
1238         bool found = false;
1239
1240         down_write(&trace_event_mutex);
1241         list_for_each_entry_safe(call, p, &ftrace_events, list) {
1242                 if (call->mod == mod) {
1243                         found = true;
1244                         __trace_remove_event_call(call);
1245                 }
1246         }
1247
1248         /* Now free the file_operations */
1249         list_for_each_entry(file_ops, &ftrace_module_file_list, list) {
1250                 if (file_ops->mod == mod)
1251                         break;
1252         }
1253         if (&file_ops->list != &ftrace_module_file_list) {
1254                 list_del(&file_ops->list);
1255                 kfree(file_ops);
1256         }
1257
1258         /*
1259          * It is safest to reset the ring buffer if the module being unloaded
1260          * registered any events.
1261          */
1262         if (found)
1263                 tracing_reset_current_online_cpus();
1264         up_write(&trace_event_mutex);
1265 }
1266
1267 static int trace_module_notify(struct notifier_block *self,
1268                                unsigned long val, void *data)
1269 {
1270         struct module *mod = data;
1271
1272         mutex_lock(&event_mutex);
1273         switch (val) {
1274         case MODULE_STATE_COMING:
1275                 trace_module_add_events(mod);
1276                 break;
1277         case MODULE_STATE_GOING:
1278                 trace_module_remove_events(mod);
1279                 break;
1280         }
1281         mutex_unlock(&event_mutex);
1282
1283         return 0;
1284 }
1285 #else
1286 static int trace_module_notify(struct notifier_block *self,
1287                                unsigned long val, void *data)
1288 {
1289         return 0;
1290 }
1291 #endif /* CONFIG_MODULES */
1292
1293 static struct notifier_block trace_module_nb = {
1294         .notifier_call = trace_module_notify,
1295         .priority = 0,
1296 };
1297
1298 extern struct ftrace_event_call __start_ftrace_events[];
1299 extern struct ftrace_event_call __stop_ftrace_events[];
1300
1301 static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
1302
1303 static __init int setup_trace_event(char *str)
1304 {
1305         strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
1306         ring_buffer_expanded = 1;
1307         tracing_selftest_disabled = 1;
1308
1309         return 1;
1310 }
1311 __setup("trace_event=", setup_trace_event);
1312
1313 static __init int event_trace_init(void)
1314 {
1315         struct ftrace_event_call *call;
1316         struct dentry *d_tracer;
1317         struct dentry *entry;
1318         struct dentry *d_events;
1319         int ret;
1320         char *buf = bootup_event_buf;
1321         char *token;
1322
1323         d_tracer = tracing_init_dentry();
1324         if (!d_tracer)
1325                 return 0;
1326
1327         entry = debugfs_create_file("available_events", 0444, d_tracer,
1328                                     (void *)&show_event_seq_ops,
1329                                     &ftrace_avail_fops);
1330         if (!entry)
1331                 pr_warning("Could not create debugfs "
1332                            "'available_events' entry\n");
1333
1334         entry = debugfs_create_file("set_event", 0644, d_tracer,
1335                                     (void *)&show_set_event_seq_ops,
1336                                     &ftrace_set_event_fops);
1337         if (!entry)
1338                 pr_warning("Could not create debugfs "
1339                            "'set_event' entry\n");
1340
1341         d_events = event_trace_events_dir();
1342         if (!d_events)
1343                 return 0;
1344
1345         /* ring buffer internal formats */
1346         trace_create_file("header_page", 0444, d_events,
1347                           ring_buffer_print_page_header,
1348                           &ftrace_show_header_fops);
1349
1350         trace_create_file("header_event", 0444, d_events,
1351                           ring_buffer_print_entry_header,
1352                           &ftrace_show_header_fops);
1353
1354         trace_create_file("enable", 0644, d_events,
1355                           NULL, &ftrace_system_enable_fops);
1356
1357         if (trace_define_common_fields())
1358                 pr_warning("tracing: Failed to allocate common fields");
1359
1360         for_each_event(call, __start_ftrace_events, __stop_ftrace_events) {
1361                 __trace_add_event_call(call, NULL, &ftrace_event_id_fops,
1362                                        &ftrace_enable_fops,
1363                                        &ftrace_event_filter_fops,
1364                                        &ftrace_event_format_fops);
1365         }
1366
1367         while (true) {
1368                 token = strsep(&buf, ",");
1369
1370                 if (!token)
1371                         break;
1372                 if (!*token)
1373                         continue;
1374
1375                 ret = ftrace_set_clr_event(token, 1);
1376                 if (ret)
1377                         pr_warning("Failed to enable trace event: %s\n", token);
1378         }
1379
1380         ret = register_module_notifier(&trace_module_nb);
1381         if (ret)
1382                 pr_warning("Failed to register trace events module notifier\n");
1383
1384         return 0;
1385 }
1386 fs_initcall(event_trace_init);
1387
1388 #ifdef CONFIG_FTRACE_STARTUP_TEST
1389
1390 static DEFINE_SPINLOCK(test_spinlock);
1391 static DEFINE_SPINLOCK(test_spinlock_irq);
1392 static DEFINE_MUTEX(test_mutex);
1393
1394 static __init void test_work(struct work_struct *dummy)
1395 {
1396         spin_lock(&test_spinlock);
1397         spin_lock_irq(&test_spinlock_irq);
1398         udelay(1);
1399         spin_unlock_irq(&test_spinlock_irq);
1400         spin_unlock(&test_spinlock);
1401
1402         mutex_lock(&test_mutex);
1403         msleep(1);
1404         mutex_unlock(&test_mutex);
1405 }
1406
1407 static __init int event_test_thread(void *unused)
1408 {
1409         void *test_malloc;
1410
1411         test_malloc = kmalloc(1234, GFP_KERNEL);
1412         if (!test_malloc)
1413                 pr_info("failed to kmalloc\n");
1414
1415         schedule_on_each_cpu(test_work);
1416
1417         kfree(test_malloc);
1418
1419         set_current_state(TASK_INTERRUPTIBLE);
1420         while (!kthread_should_stop())
1421                 schedule();
1422
1423         return 0;
1424 }
1425
1426 /*
1427  * Do various things that may trigger events.
1428  */
1429 static __init void event_test_stuff(void)
1430 {
1431         struct task_struct *test_thread;
1432
1433         test_thread = kthread_run(event_test_thread, NULL, "test-events");
1434         msleep(1);
1435         kthread_stop(test_thread);
1436 }
1437
1438 /*
1439  * For every trace event defined, we will test each trace point separately,
1440  * and then by groups, and finally all trace points.
1441  */
1442 static __init void event_trace_self_tests(void)
1443 {
1444         struct ftrace_event_call *call;
1445         struct event_subsystem *system;
1446         int ret;
1447
1448         pr_info("Running tests on trace events:\n");
1449
1450         list_for_each_entry(call, &ftrace_events, list) {
1451
1452                 /* Only test those that have a probe */
1453                 if (!call->class || !call->class->probe)
1454                         continue;
1455
1456 /*
1457  * Testing syscall events here is pretty useless, but
1458  * we still do it if configured. But this is time consuming.
1459  * What we really need is a user thread to perform the
1460  * syscalls as we test.
1461  */
1462 #ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
1463                 if (call->class->system &&
1464                     strcmp(call->class->system, "syscalls") == 0)
1465                         continue;
1466 #endif
1467
1468                 pr_info("Testing event %s: ", call->name);
1469
1470                 /*
1471                  * If an event is already enabled, someone is using
1472                  * it and the self test should not be on.
1473                  */
1474                 if (call->flags & TRACE_EVENT_FL_ENABLED) {
1475                         pr_warning("Enabled event during self test!\n");
1476                         WARN_ON_ONCE(1);
1477                         continue;
1478                 }
1479
1480                 ftrace_event_enable_disable(call, 1);
1481                 event_test_stuff();
1482                 ftrace_event_enable_disable(call, 0);
1483
1484                 pr_cont("OK\n");
1485         }
1486
1487         /* Now test at the sub system level */
1488
1489         pr_info("Running tests on trace event systems:\n");
1490
1491         list_for_each_entry(system, &event_subsystems, list) {
1492
1493                 /* the ftrace system is special, skip it */
1494                 if (strcmp(system->name, "ftrace") == 0)
1495                         continue;
1496
1497                 pr_info("Testing event system %s: ", system->name);
1498
1499                 ret = __ftrace_set_clr_event(NULL, system->name, NULL, 1);
1500                 if (WARN_ON_ONCE(ret)) {
1501                         pr_warning("error enabling system %s\n",
1502                                    system->name);
1503                         continue;
1504                 }
1505
1506                 event_test_stuff();
1507
1508                 ret = __ftrace_set_clr_event(NULL, system->name, NULL, 0);
1509                 if (WARN_ON_ONCE(ret))
1510                         pr_warning("error disabling system %s\n",
1511                                    system->name);
1512
1513                 pr_cont("OK\n");
1514         }
1515
1516         /* Test with all events enabled */
1517
1518         pr_info("Running tests on all trace events:\n");
1519         pr_info("Testing all events: ");
1520
1521         ret = __ftrace_set_clr_event(NULL, NULL, NULL, 1);
1522         if (WARN_ON_ONCE(ret)) {
1523                 pr_warning("error enabling all events\n");
1524                 return;
1525         }
1526
1527         event_test_stuff();
1528
1529         /* reset sysname */
1530         ret = __ftrace_set_clr_event(NULL, NULL, NULL, 0);
1531         if (WARN_ON_ONCE(ret)) {
1532                 pr_warning("error disabling all events\n");
1533                 return;
1534         }
1535
1536         pr_cont("OK\n");
1537 }
1538
1539 #ifdef CONFIG_FUNCTION_TRACER
1540
1541 static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
1542
1543 static void
1544 function_test_events_call(unsigned long ip, unsigned long parent_ip)
1545 {
1546         struct ring_buffer_event *event;
1547         struct ring_buffer *buffer;
1548         struct ftrace_entry *entry;
1549         unsigned long flags;
1550         long disabled;
1551         int cpu;
1552         int pc;
1553
1554         pc = preempt_count();
1555         preempt_disable_notrace();
1556         cpu = raw_smp_processor_id();
1557         disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
1558
1559         if (disabled != 1)
1560                 goto out;
1561
1562         local_save_flags(flags);
1563
1564         event = trace_current_buffer_lock_reserve(&buffer,
1565                                                   TRACE_FN, sizeof(*entry),
1566                                                   flags, pc);
1567         if (!event)
1568                 goto out;
1569         entry   = ring_buffer_event_data(event);
1570         entry->ip                       = ip;
1571         entry->parent_ip                = parent_ip;
1572
1573         trace_nowake_buffer_unlock_commit(buffer, event, flags, pc);
1574
1575  out:
1576         atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
1577         preempt_enable_notrace();
1578 }
1579
1580 static struct ftrace_ops trace_ops __initdata  =
1581 {
1582         .func = function_test_events_call,
1583 };
1584
1585 static __init void event_trace_self_test_with_function(void)
1586 {
1587         register_ftrace_function(&trace_ops);
1588         pr_info("Running tests again, along with the function tracer\n");
1589         event_trace_self_tests();
1590         unregister_ftrace_function(&trace_ops);
1591 }
1592 #else
1593 static __init void event_trace_self_test_with_function(void)
1594 {
1595 }
1596 #endif
1597
1598 static __init int event_trace_self_tests_init(void)
1599 {
1600         if (!tracing_selftest_disabled) {
1601                 event_trace_self_tests();
1602                 event_trace_self_test_with_function();
1603         }
1604
1605         return 0;
1606 }
1607
1608 late_initcall(event_trace_self_tests_init);
1609
1610 #endif