tools/perf/util/trace-event-info.c

   1 /*
   2  * Copyright (C) 2008,2009, Steven Rostedt <srostedt@redhat.com>
   3  *
   4  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; version 2 of the License (not later!)
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  20  */
  21 #define _GNU_SOURCE
  22 #include <dirent.h>
  23 #include <mntent.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <stdarg.h>
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #include <sys/wait.h>
  31 #include <pthread.h>
  32 #include <fcntl.h>
  33 #include <unistd.h>
  34 #include <ctype.h>
  35 #include <errno.h>
  36 #include <stdbool.h>
  37 #include <linux/list.h>
  38 #include <linux/kernel.h>
  39
  40 #include "../perf.h"
  41 #include "trace-event.h"
  42 #include "debugfs.h"
  43 #include "evsel.h"
  44
  45 #define VERSION "0.5"
  46
  47 #define _STR(x) #x
  48 #define STR(x) _STR(x)
  49 #define MAX_PATH 256
  50
  51 #define TRACE_CTRL      "tracing_on"
  52 #define TRACE           "trace"
  53 #define AVAILABLE       "available_tracers"
  54 #define CURRENT         "current_tracer"
  55 #define ITER_CTRL       "trace_options"
  56 #define MAX_LATENCY     "tracing_max_latency"
  57
  58 unsigned int page_size;
  59
  60 static const char *output_file = "trace.info";
  61 static int output_fd;
  62
  63 struct event_list {
  64         struct event_list *next;
  65         const char *event;
  66 };
  67
  68 struct events {
  69         struct events *sibling;
  70         struct events *children;
  71         struct events *next;
  72         char *name;
  73 };
  74
  75
  76
  77 static void die(const char *fmt, ...)
  78 {
  79         va_list ap;
  80         int ret = errno;
  81
  82         if (errno)
  83                 perror("perf");
  84         else
  85                 ret = -1;
  86
  87         va_start(ap, fmt);
  88         fprintf(stderr, "  ");
  89         vfprintf(stderr, fmt, ap);
  90         va_end(ap);
  91
  92         fprintf(stderr, "\n");
  93         exit(ret);
  94 }
  95
  96 void *malloc_or_die(unsigned int size)
  97 {
  98         void *data;
  99
 100         data = malloc(size);
 101         if (!data)
 102                 die("malloc");
 103         return data;
 104 }
 105
 106 static const char *find_debugfs(void)
 107 {
 108         const char *path = debugfs_mount(NULL);
 109
 110         if (!path)
 111                 die("Your kernel not support debugfs filesystem");
 112
 113         return path;
 114 }
 115
 116 /*
 117  * Finds the path to the debugfs/tracing
 118  * Allocates the string and stores it.
 119  */
 120 static const char *find_tracing_dir(void)
 121 {
 122         static char *tracing;
 123         static int tracing_found;
 124         const char *debugfs;
 125
 126         if (tracing_found)
 127                 return tracing;
 128
 129         debugfs = find_debugfs();
 130
 131         tracing = malloc_or_die(strlen(debugfs) + 9);
 132
 133         sprintf(tracing, "%s/tracing", debugfs);
 134
 135         tracing_found = 1;
 136         return tracing;
 137 }
 138
 139 static char *get_tracing_file(const char *name)
 140 {
 141         const char *tracing;
 142         char *file;
 143
 144         tracing = find_tracing_dir();
 145         if (!tracing)
 146                 return NULL;
 147
 148         file = malloc_or_die(strlen(tracing) + strlen(name) + 2);
 149
 150         sprintf(file, "%s/%s", tracing, name);
 151         return file;
 152 }
 153
 154 static void put_tracing_file(char *file)
 155 {
 156         free(file);
 157 }
 158
 159 static ssize_t calc_data_size;
 160
 161 static ssize_t write_or_die(const void *buf, size_t len)
 162 {
 163         int ret;
 164
 165         if (calc_data_size) {
 166                 calc_data_size += len;
 167                 return len;
 168         }
 169
 170         ret = write(output_fd, buf, len);
 171         if (ret < 0)
 172                 die("writing to '%s'", output_file);
 173
 174         return ret;
 175 }
 176
 177 int bigendian(void)
 178 {
 179         unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
 180         unsigned int *ptr;
 181
 182         ptr = (unsigned int *)(void *)str;
 183         return *ptr == 0x01020304;
 184 }
 185
 186 /* unfortunately, you can not stat debugfs or proc files for size */
 187 static void record_file(const char *file, size_t hdr_sz)
 188 {
 189         unsigned long long size = 0;
 190         char buf[BUFSIZ], *sizep;
 191         off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
 192         int r, fd;
 193
 194         fd = open(file, O_RDONLY);
 195         if (fd < 0)
 196                 die("Can't read '%s'", file);
 197
 198         /* put in zeros for file size, then fill true size later */
 199         if (hdr_sz)
 200                 write_or_die(&size, hdr_sz);
 201
 202         do {
 203                 r = read(fd, buf, BUFSIZ);
 204                 if (r > 0) {
 205                         size += r;
 206                         write_or_die(buf, r);
 207                 }
 208         } while (r > 0);
 209         close(fd);
 210
 211         /* ugh, handle big-endian hdr_size == 4 */
 212         sizep = (char*)&size;
 213         if (bigendian())
 214                 sizep += sizeof(u64) - hdr_sz;
 215
 216         if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0)
 217                 die("writing to %s", output_file);
 218 }
 219
 220 static void read_header_files(void)
 221 {
 222         char *path;
 223         struct stat st;
 224
 225         path = get_tracing_file("events/header_page");
 226         if (stat(path, &st) < 0)
 227                 die("can't read '%s'", path);
 228
 229         write_or_die("header_page", 12);
 230         record_file(path, 8);
 231         put_tracing_file(path);
 232
 233         path = get_tracing_file("events/header_event");
 234         if (stat(path, &st) < 0)
 235                 die("can't read '%s'", path);
 236
 237         write_or_die("header_event", 13);
 238         record_file(path, 8);
 239         put_tracing_file(path);
 240 }
 241
 242 static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
 243 {
 244         while (tps) {
 245                 if (!strcmp(sys, tps->name))
 246                         return true;
 247                 tps = tps->next;
 248         }
 249
 250         return false;
 251 }
 252
 253 static void copy_event_system(const char *sys, struct tracepoint_path *tps)
 254 {
 255         struct dirent *dent;
 256         struct stat st;
 257         char *format;
 258         DIR *dir;
 259         int count = 0;
 260         int ret;
 261
 262         dir = opendir(sys);
 263         if (!dir)
 264                 die("can't read directory '%s'", sys);
 265
 266         while ((dent = readdir(dir))) {
 267                 if (dent->d_type != DT_DIR ||
 268                     strcmp(dent->d_name, ".") == 0 ||
 269                     strcmp(dent->d_name, "..") == 0 ||
 270                     !name_in_tp_list(dent->d_name, tps))
 271                         continue;
 272                 format = malloc_or_die(strlen(sys) + strlen(dent->d_name) + 10);
 273                 sprintf(format, "%s/%s/format", sys, dent->d_name);
 274                 ret = stat(format, &st);
 275                 free(format);
 276                 if (ret < 0)
 277                         continue;
 278                 count++;
 279         }
 280
 281         write_or_die(&count, 4);
 282
 283         rewinddir(dir);
 284         while ((dent = readdir(dir))) {
 285                 if (dent->d_type != DT_DIR ||
 286                     strcmp(dent->d_name, ".") == 0 ||
 287                     strcmp(dent->d_name, "..") == 0 ||
 288                     !name_in_tp_list(dent->d_name, tps))
 289                         continue;
 290                 format = malloc_or_die(strlen(sys) + strlen(dent->d_name) + 10);
 291                 sprintf(format, "%s/%s/format", sys, dent->d_name);
 292                 ret = stat(format, &st);
 293
 294                 if (ret >= 0)
 295                         record_file(format, 8);
 296
 297                 free(format);
 298         }
 299         closedir(dir);
 300 }
 301
 302 static void read_ftrace_files(struct tracepoint_path *tps)
 303 {
 304         char *path;
 305
 306         path = get_tracing_file("events/ftrace");
 307
 308         copy_event_system(path, tps);
 309
 310         put_tracing_file(path);
 311 }
 312
 313 static bool system_in_tp_list(char *sys, struct tracepoint_path *tps)
 314 {
 315         while (tps) {
 316                 if (!strcmp(sys, tps->system))
 317                         return true;
 318                 tps = tps->next;
 319         }
 320
 321         return false;
 322 }
 323
 324 static void read_event_files(struct tracepoint_path *tps)
 325 {
 326         struct dirent *dent;
 327         struct stat st;
 328         char *path;
 329         char *sys;
 330         DIR *dir;
 331         int count = 0;
 332         int ret;
 333
 334         path = get_tracing_file("events");
 335
 336         dir = opendir(path);
 337         if (!dir)
 338                 die("can't read directory '%s'", path);
 339
 340         while ((dent = readdir(dir))) {
 341                 if (dent->d_type != DT_DIR ||
 342                     strcmp(dent->d_name, ".") == 0 ||
 343                     strcmp(dent->d_name, "..") == 0 ||
 344                     strcmp(dent->d_name, "ftrace") == 0 ||
 345                     !system_in_tp_list(dent->d_name, tps))
 346                         continue;
 347                 count++;
 348         }
 349
 350         write_or_die(&count, 4);
 351
 352         rewinddir(dir);
 353         while ((dent = readdir(dir))) {
 354                 if (dent->d_type != DT_DIR ||
 355                     strcmp(dent->d_name, ".") == 0 ||
 356                     strcmp(dent->d_name, "..") == 0 ||
 357                     strcmp(dent->d_name, "ftrace") == 0 ||
 358                     !system_in_tp_list(dent->d_name, tps))
 359                         continue;
 360                 sys = malloc_or_die(strlen(path) + strlen(dent->d_name) + 2);
 361                 sprintf(sys, "%s/%s", path, dent->d_name);
 362                 ret = stat(sys, &st);
 363                 if (ret >= 0) {
 364                         write_or_die(dent->d_name, strlen(dent->d_name) + 1);
 365                         copy_event_system(sys, tps);
 366                 }
 367                 free(sys);
 368         }
 369
 370         closedir(dir);
 371         put_tracing_file(path);
 372 }
 373
 374 static void read_proc_kallsyms(void)
 375 {
 376         unsigned int size;
 377         const char *path = "/proc/kallsyms";
 378         struct stat st;
 379         int ret;
 380
 381         ret = stat(path, &st);
 382         if (ret < 0) {
 383                 /* not found */
 384                 size = 0;
 385                 write_or_die(&size, 4);
 386                 return;
 387         }
 388         record_file(path, 4);
 389 }
 390
 391 static void read_ftrace_printk(void)
 392 {
 393         unsigned int size;
 394         char *path;
 395         struct stat st;
 396         int ret;
 397
 398         path = get_tracing_file("printk_formats");
 399         ret = stat(path, &st);
 400         if (ret < 0) {
 401                 /* not found */
 402                 size = 0;
 403                 write_or_die(&size, 4);
 404                 goto out;
 405         }
 406         record_file(path, 4);
 407
 408 out:
 409         put_tracing_file(path);
 410 }
 411
 412 static struct tracepoint_path *
 413 get_tracepoints_path(struct list_head *pattrs)
 414 {
 415         struct tracepoint_path path, *ppath = &path;
 416         struct perf_evsel *pos;
 417         int nr_tracepoints = 0;
 418
 419         list_for_each_entry(pos, pattrs, node) {
 420                 if (pos->attr.type != PERF_TYPE_TRACEPOINT)
 421                         continue;
 422                 ++nr_tracepoints;
 423                 ppath->next = tracepoint_id_to_path(pos->attr.config);
 424                 if (!ppath->next)
 425                         die("%s\n", "No memory to alloc tracepoints list");
 426                 ppath = ppath->next;
 427         }
 428
 429         return nr_tracepoints > 0 ? path.next : NULL;
 430 }
 431
 432 static void
 433 put_tracepoints_path(struct tracepoint_path *tps)
 434 {
 435         while (tps) {
 436                 struct tracepoint_path *t = tps;
 437
 438                 tps = tps->next;
 439                 free(t->name);
 440                 free(t->system);
 441                 free(t);
 442         }
 443 }
 444
 445 bool have_tracepoints(struct list_head *pattrs)
 446 {
 447         struct perf_evsel *pos;
 448
 449         list_for_each_entry(pos, pattrs, node)
 450                 if (pos->attr.type == PERF_TYPE_TRACEPOINT)
 451                         return true;
 452
 453         return false;
 454 }
 455
 456 static void tracing_data_header(void)
 457 {
 458         char buf[20];
 459
 460         /* just guessing this is someone's birthday.. ;) */
 461         buf[0] = 23;
 462         buf[1] = 8;
 463         buf[2] = 68;
 464         memcpy(buf + 3, "tracing", 7);
 465
 466         write_or_die(buf, 10);
 467
 468         write_or_die(VERSION, strlen(VERSION) + 1);
 469
 470         /* save endian */
 471         if (bigendian())
 472                 buf[0] = 1;
 473         else
 474                 buf[0] = 0;
 475
 476         write_or_die(buf, 1);
 477
 478         /* save size of long */
 479         buf[0] = sizeof(long);
 480         write_or_die(buf, 1);
 481
 482         /* save page_size */
 483         page_size = sysconf(_SC_PAGESIZE);
 484         write_or_die(&page_size, 4);
 485 }
 486
 487 struct tracing_data *tracing_data_get(struct list_head *pattrs,
 488                                       int fd, bool temp)
 489 {
 490         struct tracepoint_path *tps;
 491         struct tracing_data *tdata;
 492
 493         output_fd = fd;
 494
 495         tps = get_tracepoints_path(pattrs);
 496         if (!tps)
 497                 return NULL;
 498
 499         tdata = malloc_or_die(sizeof(*tdata));
 500         tdata->temp = temp;
 501         tdata->size = 0;
 502
 503         if (temp) {
 504                 int temp_fd;
 505
 506                 snprintf(tdata->temp_file, sizeof(tdata->temp_file),
 507                          "/tmp/perf-XXXXXX");
 508                 if (!mkstemp(tdata->temp_file))
 509                         die("Can't make temp file");
 510
 511                 temp_fd = open(tdata->temp_file, O_RDWR);
 512                 if (temp_fd < 0)
 513                         die("Can't read '%s'", tdata->temp_file);
 514
 515                 /*
 516                  * Set the temp file the default output, so all the
 517                  * tracing data are stored into it.
 518                  */
 519                 output_fd = temp_fd;
 520         }
 521
 522         tracing_data_header();
 523         read_header_files();
 524         read_ftrace_files(tps);
 525         read_event_files(tps);
 526         read_proc_kallsyms();
 527         read_ftrace_printk();
 528
 529         /*
 530          * All tracing data are stored by now, we can restore
 531          * the default output file in case we used temp file.
 532          */
 533         if (temp) {
 534                 tdata->size = lseek(output_fd, 0, SEEK_CUR);
 535                 close(output_fd);
 536                 output_fd = fd;
 537         }
 538
 539         put_tracepoints_path(tps);
 540         return tdata;
 541 }
 542
 543 void tracing_data_put(struct tracing_data *tdata)
 544 {
 545         if (tdata->temp) {
 546                 record_file(tdata->temp_file, 0);
 547                 unlink(tdata->temp_file);
 548         }
 549
 550         free(tdata);
 551 }
 552
 553 int read_tracing_data(int fd, struct list_head *pattrs)
 554 {
 555         struct tracing_data *tdata;
 556
 557         /*
 558          * We work over the real file, so we can write data
 559          * directly, no temp file is needed.
 560          */
 561         tdata = tracing_data_get(pattrs, fd, false);
 562         if (!tdata)
 563                 return -ENOMEM;
 564
 565         tracing_data_put(tdata);
 566         return 0;
 567 }