tools/perf/util/probe-file.c

   1 /*
   2  * probe-file.c : operate ftrace k/uprobe events files
   3  *
   4  * Written by Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
   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; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  */
  17 #include <sys/uio.h>
  18 #include "util.h"
  19 #include "event.h"
  20 #include "strlist.h"
  21 #include "debug.h"
  22 #include "cache.h"
  23 #include "color.h"
  24 #include "symbol.h"
  25 #include "thread.h"
  26 #include <api/fs/tracing_path.h>
  27 #include "probe-event.h"
  28 #include "probe-file.h"
  29 #include "session.h"
  30 #include "perf_regs.h"
  31 #include "string2.h"
  32
  33 /* 4096 - 2 ('\n' + '\0') */
  34 #define MAX_CMDLEN 4094
  35
  36 static void print_open_warning(int err, bool uprobe)
  37 {
  38         char sbuf[STRERR_BUFSIZE];
  39
  40         if (err == -ENOENT) {
  41                 const char *config;
  42
  43                 if (uprobe)
  44                         config = "CONFIG_UPROBE_EVENTS";
  45                 else
  46                         config = "CONFIG_KPROBE_EVENTS";
  47
  48                 pr_warning("%cprobe_events file does not exist"
  49                            " - please rebuild kernel with %s.\n",
  50                            uprobe ? 'u' : 'k', config);
  51         } else if (err == -ENOTSUP)
  52                 pr_warning("Tracefs or debugfs is not mounted.\n");
  53         else
  54                 pr_warning("Failed to open %cprobe_events: %s\n",
  55                            uprobe ? 'u' : 'k',
  56                            str_error_r(-err, sbuf, sizeof(sbuf)));
  57 }
  58
  59 static void print_both_open_warning(int kerr, int uerr)
  60 {
  61         /* Both kprobes and uprobes are disabled, warn it. */
  62         if (kerr == -ENOTSUP && uerr == -ENOTSUP)
  63                 pr_warning("Tracefs or debugfs is not mounted.\n");
  64         else if (kerr == -ENOENT && uerr == -ENOENT)
  65                 pr_warning("Please rebuild kernel with CONFIG_KPROBE_EVENTS "
  66                            "or/and CONFIG_UPROBE_EVENTS.\n");
  67         else {
  68                 char sbuf[STRERR_BUFSIZE];
  69                 pr_warning("Failed to open kprobe events: %s.\n",
  70                            str_error_r(-kerr, sbuf, sizeof(sbuf)));
  71                 pr_warning("Failed to open uprobe events: %s.\n",
  72                            str_error_r(-uerr, sbuf, sizeof(sbuf)));
  73         }
  74 }
  75
  76 int open_trace_file(const char *trace_file, bool readwrite)
  77 {
  78         char buf[PATH_MAX];
  79         int ret;
  80
  81         ret = e_snprintf(buf, PATH_MAX, "%s/%s",
  82                          tracing_path, trace_file);
  83         if (ret >= 0) {
  84                 pr_debug("Opening %s write=%d\n", buf, readwrite);
  85                 if (readwrite && !probe_event_dry_run)
  86                         ret = open(buf, O_RDWR | O_APPEND, 0);
  87                 else
  88                         ret = open(buf, O_RDONLY, 0);
  89
  90                 if (ret < 0)
  91                         ret = -errno;
  92         }
  93         return ret;
  94 }
  95
  96 static int open_kprobe_events(bool readwrite)
  97 {
  98         return open_trace_file("kprobe_events", readwrite);
  99 }
 100
 101 static int open_uprobe_events(bool readwrite)
 102 {
 103         return open_trace_file("uprobe_events", readwrite);
 104 }
 105
 106 int probe_file__open(int flag)
 107 {
 108         int fd;
 109
 110         if (flag & PF_FL_UPROBE)
 111                 fd = open_uprobe_events(flag & PF_FL_RW);
 112         else
 113                 fd = open_kprobe_events(flag & PF_FL_RW);
 114         if (fd < 0)
 115                 print_open_warning(fd, flag & PF_FL_UPROBE);
 116
 117         return fd;
 118 }
 119
 120 int probe_file__open_both(int *kfd, int *ufd, int flag)
 121 {
 122         if (!kfd || !ufd)
 123                 return -EINVAL;
 124
 125         *kfd = open_kprobe_events(flag & PF_FL_RW);
 126         *ufd = open_uprobe_events(flag & PF_FL_RW);
 127         if (*kfd < 0 && *ufd < 0) {
 128                 print_both_open_warning(*kfd, *ufd);
 129                 return *kfd;
 130         }
 131
 132         return 0;
 133 }
 134
 135 /* Get raw string list of current kprobe_events  or uprobe_events */
 136 struct strlist *probe_file__get_rawlist(int fd)
 137 {
 138         int ret, idx, fddup;
 139         FILE *fp;
 140         char buf[MAX_CMDLEN];
 141         char *p;
 142         struct strlist *sl;
 143
 144         if (fd < 0)
 145                 return NULL;
 146
 147         sl = strlist__new(NULL, NULL);
 148         if (sl == NULL)
 149                 return NULL;
 150
 151         fddup = dup(fd);
 152         if (fddup < 0)
 153                 goto out_free_sl;
 154
 155         fp = fdopen(fddup, "r");
 156         if (!fp)
 157                 goto out_close_fddup;
 158
 159         while (!feof(fp)) {
 160                 p = fgets(buf, MAX_CMDLEN, fp);
 161                 if (!p)
 162                         break;
 163
 164                 idx = strlen(p) - 1;
 165                 if (p[idx] == '\n')
 166                         p[idx] = '\0';
 167                 ret = strlist__add(sl, buf);
 168                 if (ret < 0) {
 169                         pr_debug("strlist__add failed (%d)\n", ret);
 170                         goto out_close_fp;
 171                 }
 172         }
 173         fclose(fp);
 174
 175         return sl;
 176
 177 out_close_fp:
 178         fclose(fp);
 179         goto out_free_sl;
 180 out_close_fddup:
 181         close(fddup);
 182 out_free_sl:
 183         strlist__delete(sl);
 184         return NULL;
 185 }
 186
 187 static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
 188 {
 189         char buf[128];
 190         struct strlist *sl, *rawlist;
 191         struct str_node *ent;
 192         struct probe_trace_event tev;
 193         int ret = 0;
 194
 195         memset(&tev, 0, sizeof(tev));
 196         rawlist = probe_file__get_rawlist(fd);
 197         if (!rawlist)
 198                 return NULL;
 199         sl = strlist__new(NULL, NULL);
 200         strlist__for_each_entry(ent, rawlist) {
 201                 ret = parse_probe_trace_command(ent->s, &tev);
 202                 if (ret < 0)
 203                         break;
 204                 if (include_group) {
 205                         ret = e_snprintf(buf, 128, "%s:%s", tev.group,
 206                                         tev.event);
 207                         if (ret >= 0)
 208                                 ret = strlist__add(sl, buf);
 209                 } else
 210                         ret = strlist__add(sl, tev.event);
 211                 clear_probe_trace_event(&tev);
 212                 if (ret < 0)
 213                         break;
 214         }
 215         strlist__delete(rawlist);
 216
 217         if (ret < 0) {
 218                 strlist__delete(sl);
 219                 return NULL;
 220         }
 221         return sl;
 222 }
 223
 224 /* Get current perf-probe event names */
 225 struct strlist *probe_file__get_namelist(int fd)
 226 {
 227         return __probe_file__get_namelist(fd, false);
 228 }
 229
 230 int probe_file__add_event(int fd, struct probe_trace_event *tev)
 231 {
 232         int ret = 0;
 233         char *buf = synthesize_probe_trace_command(tev);
 234         char sbuf[STRERR_BUFSIZE];
 235
 236         if (!buf) {
 237                 pr_debug("Failed to synthesize probe trace event.\n");
 238                 return -EINVAL;
 239         }
 240
 241         pr_debug("Writing event: %s\n", buf);
 242         if (!probe_event_dry_run) {
 243                 if (write(fd, buf, strlen(buf)) < (int)strlen(buf)) {
 244                         ret = -errno;
 245                         pr_warning("Failed to write event: %s\n",
 246                                    str_error_r(errno, sbuf, sizeof(sbuf)));
 247                 }
 248         }
 249         free(buf);
 250
 251         return ret;
 252 }
 253
 254 static int __del_trace_probe_event(int fd, struct str_node *ent)
 255 {
 256         char *p;
 257         char buf[128];
 258         int ret;
 259
 260         /* Convert from perf-probe event to trace-probe event */
 261         ret = e_snprintf(buf, 128, "-:%s", ent->s);
 262         if (ret < 0)
 263                 goto error;
 264
 265         p = strchr(buf + 2, ':');
 266         if (!p) {
 267                 pr_debug("Internal error: %s should have ':' but not.\n",
 268                          ent->s);
 269                 ret = -ENOTSUP;
 270                 goto error;
 271         }
 272         *p = '/';
 273
 274         pr_debug("Writing event: %s\n", buf);
 275         ret = write(fd, buf, strlen(buf));
 276         if (ret < 0) {
 277                 ret = -errno;
 278                 goto error;
 279         }
 280
 281         return 0;
 282 error:
 283         pr_warning("Failed to delete event: %s\n",
 284                    str_error_r(-ret, buf, sizeof(buf)));
 285         return ret;
 286 }
 287
 288 int probe_file__get_events(int fd, struct strfilter *filter,
 289                            struct strlist *plist)
 290 {
 291         struct strlist *namelist;
 292         struct str_node *ent;
 293         const char *p;
 294         int ret = -ENOENT;
 295
 296         if (!plist)
 297                 return -EINVAL;
 298
 299         namelist = __probe_file__get_namelist(fd, true);
 300         if (!namelist)
 301                 return -ENOENT;
 302
 303         strlist__for_each_entry(ent, namelist) {
 304                 p = strchr(ent->s, ':');
 305                 if ((p && strfilter__compare(filter, p + 1)) ||
 306                     strfilter__compare(filter, ent->s)) {
 307                         strlist__add(plist, ent->s);
 308                         ret = 0;
 309                 }
 310         }
 311         strlist__delete(namelist);
 312
 313         return ret;
 314 }
 315
 316 int probe_file__del_strlist(int fd, struct strlist *namelist)
 317 {
 318         int ret = 0;
 319         struct str_node *ent;
 320
 321         strlist__for_each_entry(ent, namelist) {
 322                 ret = __del_trace_probe_event(fd, ent);
 323                 if (ret < 0)
 324                         break;
 325         }
 326         return ret;
 327 }
 328
 329 int probe_file__del_events(int fd, struct strfilter *filter)
 330 {
 331         struct strlist *namelist;
 332         int ret;
 333
 334         namelist = strlist__new(NULL, NULL);
 335         if (!namelist)
 336                 return -ENOMEM;
 337
 338         ret = probe_file__get_events(fd, filter, namelist);
 339         if (ret < 0)
 340                 return ret;
 341
 342         ret = probe_file__del_strlist(fd, namelist);
 343         strlist__delete(namelist);
 344
 345         return ret;
 346 }
 347
 348 /* Caller must ensure to remove this entry from list */
 349 static void probe_cache_entry__delete(struct probe_cache_entry *entry)
 350 {
 351         if (entry) {
 352                 BUG_ON(!list_empty(&entry->node));
 353
 354                 strlist__delete(entry->tevlist);
 355                 clear_perf_probe_event(&entry->pev);
 356                 zfree(&entry->spev);
 357                 free(entry);
 358         }
 359 }
 360
 361 static struct probe_cache_entry *
 362 probe_cache_entry__new(struct perf_probe_event *pev)
 363 {
 364         struct probe_cache_entry *entry = zalloc(sizeof(*entry));
 365
 366         if (entry) {
 367                 INIT_LIST_HEAD(&entry->node);
 368                 entry->tevlist = strlist__new(NULL, NULL);
 369                 if (!entry->tevlist)
 370                         zfree(&entry);
 371                 else if (pev) {
 372                         entry->spev = synthesize_perf_probe_command(pev);
 373                         if (!entry->spev ||
 374                             perf_probe_event__copy(&entry->pev, pev) < 0) {
 375                                 probe_cache_entry__delete(entry);
 376                                 return NULL;
 377                         }
 378                 }
 379         }
 380
 381         return entry;
 382 }
 383
 384 int probe_cache_entry__get_event(struct probe_cache_entry *entry,
 385                                  struct probe_trace_event **tevs)
 386 {
 387         struct probe_trace_event *tev;
 388         struct str_node *node;
 389         int ret, i;
 390
 391         ret = strlist__nr_entries(entry->tevlist);
 392         if (ret > probe_conf.max_probes)
 393                 return -E2BIG;
 394
 395         *tevs = zalloc(ret * sizeof(*tev));
 396         if (!*tevs)
 397                 return -ENOMEM;
 398
 399         i = 0;
 400         strlist__for_each_entry(node, entry->tevlist) {
 401                 tev = &(*tevs)[i++];
 402                 ret = parse_probe_trace_command(node->s, tev);
 403                 if (ret < 0)
 404                         break;
 405         }
 406         return i;
 407 }
 408
 409 /* For the kernel probe caches, pass target = NULL or DSO__NAME_KALLSYMS */
 410 static int probe_cache__open(struct probe_cache *pcache, const char *target)
 411 {
 412         char cpath[PATH_MAX];
 413         char sbuildid[SBUILD_ID_SIZE];
 414         char *dir_name = NULL;
 415         bool is_kallsyms = false;
 416         int ret, fd;
 417
 418         if (target && build_id_cache__cached(target)) {
 419                 /* This is a cached buildid */
 420                 strncpy(sbuildid, target, SBUILD_ID_SIZE);
 421                 dir_name = build_id_cache__linkname(sbuildid, NULL, 0);
 422                 goto found;
 423         }
 424
 425         if (!target || !strcmp(target, DSO__NAME_KALLSYMS)) {
 426                 target = DSO__NAME_KALLSYMS;
 427                 is_kallsyms = true;
 428                 ret = sysfs__sprintf_build_id("/", sbuildid);
 429         } else
 430                 ret = filename__sprintf_build_id(target, sbuildid);
 431
 432         if (ret < 0) {
 433                 pr_debug("Failed to get build-id from %s.\n", target);
 434                 return ret;
 435         }
 436
 437         /* If we have no buildid cache, make it */
 438         if (!build_id_cache__cached(sbuildid)) {
 439                 ret = build_id_cache__add_s(sbuildid, target,
 440                                             is_kallsyms, NULL);
 441                 if (ret < 0) {
 442                         pr_debug("Failed to add build-id cache: %s\n", target);
 443                         return ret;
 444                 }
 445         }
 446
 447         dir_name = build_id_cache__cachedir(sbuildid, target, is_kallsyms,
 448                                             false);
 449 found:
 450         if (!dir_name) {
 451                 pr_debug("Failed to get cache from %s\n", target);
 452                 return -ENOMEM;
 453         }
 454
 455         snprintf(cpath, PATH_MAX, "%s/probes", dir_name);
 456         fd = open(cpath, O_CREAT | O_RDWR, 0644);
 457         if (fd < 0)
 458                 pr_debug("Failed to open cache(%d): %s\n", fd, cpath);
 459         free(dir_name);
 460         pcache->fd = fd;
 461
 462         return fd;
 463 }
 464
 465 static int probe_cache__load(struct probe_cache *pcache)
 466 {
 467         struct probe_cache_entry *entry = NULL;
 468         char buf[MAX_CMDLEN], *p;
 469         int ret = 0, fddup;
 470         FILE *fp;
 471
 472         fddup = dup(pcache->fd);
 473         if (fddup < 0)
 474                 return -errno;
 475         fp = fdopen(fddup, "r");
 476         if (!fp) {
 477                 close(fddup);
 478                 return -EINVAL;
 479         }
 480
 481         while (!feof(fp)) {
 482                 if (!fgets(buf, MAX_CMDLEN, fp))
 483                         break;
 484                 p = strchr(buf, '\n');
 485                 if (p)
 486                         *p = '\0';
 487                 /* #perf_probe_event or %sdt_event */
 488                 if (buf[0] == '#' || buf[0] == '%') {
 489                         entry = probe_cache_entry__new(NULL);
 490                         if (!entry) {
 491                                 ret = -ENOMEM;
 492                                 goto out;
 493                         }
 494                         if (buf[0] == '%')
 495                                 entry->sdt = true;
 496                         entry->spev = strdup(buf + 1);
 497                         if (entry->spev)
 498                                 ret = parse_perf_probe_command(buf + 1,
 499                                                                 &entry->pev);
 500                         else
 501                                 ret = -ENOMEM;
 502                         if (ret < 0) {
 503                                 probe_cache_entry__delete(entry);
 504                                 goto out;
 505                         }
 506                         list_add_tail(&entry->node, &pcache->entries);
 507                 } else {        /* trace_probe_event */
 508                         if (!entry) {
 509                                 ret = -EINVAL;
 510                                 goto out;
 511                         }
 512                         strlist__add(entry->tevlist, buf);
 513                 }
 514         }
 515 out:
 516         fclose(fp);
 517         return ret;
 518 }
 519
 520 static struct probe_cache *probe_cache__alloc(void)
 521 {
 522         struct probe_cache *pcache = zalloc(sizeof(*pcache));
 523
 524         if (pcache) {
 525                 INIT_LIST_HEAD(&pcache->entries);
 526                 pcache->fd = -EINVAL;
 527         }
 528         return pcache;
 529 }
 530
 531 void probe_cache__purge(struct probe_cache *pcache)
 532 {
 533         struct probe_cache_entry *entry, *n;
 534
 535         list_for_each_entry_safe(entry, n, &pcache->entries, node) {
 536                 list_del_init(&entry->node);
 537                 probe_cache_entry__delete(entry);
 538         }
 539 }
 540
 541 void probe_cache__delete(struct probe_cache *pcache)
 542 {
 543         if (!pcache)
 544                 return;
 545
 546         probe_cache__purge(pcache);
 547         if (pcache->fd > 0)
 548                 close(pcache->fd);
 549         free(pcache);
 550 }
 551
 552 struct probe_cache *probe_cache__new(const char *target)
 553 {
 554         struct probe_cache *pcache = probe_cache__alloc();
 555         int ret;
 556
 557         if (!pcache)
 558                 return NULL;
 559
 560         ret = probe_cache__open(pcache, target);
 561         if (ret < 0) {
 562                 pr_debug("Cache open error: %d\n", ret);
 563                 goto out_err;
 564         }
 565
 566         ret = probe_cache__load(pcache);
 567         if (ret < 0) {
 568                 pr_debug("Cache read error: %d\n", ret);
 569                 goto out_err;
 570         }
 571
 572         return pcache;
 573
 574 out_err:
 575         probe_cache__delete(pcache);
 576         return NULL;
 577 }
 578
 579 static bool streql(const char *a, const char *b)
 580 {
 581         if (a == b)
 582                 return true;
 583
 584         if (!a || !b)
 585                 return false;
 586
 587         return !strcmp(a, b);
 588 }
 589
 590 struct probe_cache_entry *
 591 probe_cache__find(struct probe_cache *pcache, struct perf_probe_event *pev)
 592 {
 593         struct probe_cache_entry *entry = NULL;
 594         char *cmd = synthesize_perf_probe_command(pev);
 595
 596         if (!cmd)
 597                 return NULL;
 598
 599         for_each_probe_cache_entry(entry, pcache) {
 600                 if (pev->sdt) {
 601                         if (entry->pev.event &&
 602                             streql(entry->pev.event, pev->event) &&
 603                             (!pev->group ||
 604                              streql(entry->pev.group, pev->group)))
 605                                 goto found;
 606
 607                         continue;
 608                 }
 609                 /* Hit if same event name or same command-string */
 610                 if ((pev->event &&
 611                      (streql(entry->pev.group, pev->group) &&
 612                       streql(entry->pev.event, pev->event))) ||
 613                     (!strcmp(entry->spev, cmd)))
 614                         goto found;
 615         }
 616         entry = NULL;
 617
 618 found:
 619         free(cmd);
 620         return entry;
 621 }
 622
 623 struct probe_cache_entry *
 624 probe_cache__find_by_name(struct probe_cache *pcache,
 625                           const char *group, const char *event)
 626 {
 627         struct probe_cache_entry *entry = NULL;
 628
 629         for_each_probe_cache_entry(entry, pcache) {
 630                 /* Hit if same event name or same command-string */
 631                 if (streql(entry->pev.group, group) &&
 632                     streql(entry->pev.event, event))
 633                         goto found;
 634         }
 635         entry = NULL;
 636
 637 found:
 638         return entry;
 639 }
 640
 641 int probe_cache__add_entry(struct probe_cache *pcache,
 642                            struct perf_probe_event *pev,
 643                            struct probe_trace_event *tevs, int ntevs)
 644 {
 645         struct probe_cache_entry *entry = NULL;
 646         char *command;
 647         int i, ret = 0;
 648
 649         if (!pcache || !pev || !tevs || ntevs <= 0) {
 650                 ret = -EINVAL;
 651                 goto out_err;
 652         }
 653
 654         /* Remove old cache entry */
 655         entry = probe_cache__find(pcache, pev);
 656         if (entry) {
 657                 list_del_init(&entry->node);
 658                 probe_cache_entry__delete(entry);
 659         }
 660
 661         ret = -ENOMEM;
 662         entry = probe_cache_entry__new(pev);
 663         if (!entry)
 664                 goto out_err;
 665
 666         for (i = 0; i < ntevs; i++) {
 667                 if (!tevs[i].point.symbol)
 668                         continue;
 669
 670                 command = synthesize_probe_trace_command(&tevs[i]);
 671                 if (!command)
 672                         goto out_err;
 673                 strlist__add(entry->tevlist, command);
 674                 free(command);
 675         }
 676         list_add_tail(&entry->node, &pcache->entries);
 677         pr_debug("Added probe cache: %d\n", ntevs);
 678         return 0;
 679
 680 out_err:
 681         pr_debug("Failed to add probe caches\n");
 682         probe_cache_entry__delete(entry);
 683         return ret;
 684 }
 685
 686 #ifdef HAVE_GELF_GETNOTE_SUPPORT
 687 static unsigned long long sdt_note__get_addr(struct sdt_note *note)
 688 {
 689         return note->bit32 ? (unsigned long long)note->addr.a32[0]
 690                  : (unsigned long long)note->addr.a64[0];
 691 }
 692
 693 static const char * const type_to_suffix[] = {
 694         ":s64", "", "", "", ":s32", "", ":s16", ":s8",
 695         "", ":u8", ":u16", "", ":u32", "", "", "", ":u64"
 696 };
 697
 698 /*
 699  * Isolate the string number and convert it into a decimal value;
 700  * this will be an index to get suffix of the uprobe name (defining
 701  * the type)
 702  */
 703 static int sdt_arg_parse_size(char *n_ptr, const char **suffix)
 704 {
 705         long type_idx;
 706
 707         type_idx = strtol(n_ptr, NULL, 10);
 708         if (type_idx < -8 || type_idx > 8) {
 709                 pr_debug4("Failed to get a valid sdt type\n");
 710                 return -1;
 711         }
 712
 713         *suffix = type_to_suffix[type_idx + 8];
 714         return 0;
 715 }
 716
 717 static int synthesize_sdt_probe_arg(struct strbuf *buf, int i, const char *arg)
 718 {
 719         char *op, *desc = strdup(arg), *new_op = NULL;
 720         const char *suffix = "";
 721         int ret = -1;
 722
 723         if (desc == NULL) {
 724                 pr_debug4("Allocation error\n");
 725                 return ret;
 726         }
 727
 728         /*
 729          * Argument is in N@OP format. N is size of the argument and OP is
 730          * the actual assembly operand. N can be omitted; in that case
 731          * argument is just OP(without @).
 732          */
 733         op = strchr(desc, '@');
 734         if (op) {
 735                 op[0] = '\0';
 736                 op++;
 737
 738                 if (sdt_arg_parse_size(desc, &suffix))
 739                         goto error;
 740         } else {
 741                 op = desc;
 742         }
 743
 744         ret = arch_sdt_arg_parse_op(op, &new_op);
 745
 746         if (ret < 0)
 747                 goto error;
 748
 749         if (ret == SDT_ARG_VALID) {
 750                 ret = strbuf_addf(buf, " arg%d=%s%s", i + 1, new_op, suffix);
 751                 if (ret < 0)
 752                         goto error;
 753         }
 754
 755         ret = 0;
 756 error:
 757         free(desc);
 758         free(new_op);
 759         return ret;
 760 }
 761
 762 static char *synthesize_sdt_probe_command(struct sdt_note *note,
 763                                         const char *pathname,
 764                                         const char *sdtgrp)
 765 {
 766         struct strbuf buf;
 767         char *ret = NULL, **args;
 768         int i, args_count;
 769
 770         if (strbuf_init(&buf, 32) < 0)
 771                 return NULL;
 772
 773         if (strbuf_addf(&buf, "p:%s/%s %s:0x%llx",
 774                                 sdtgrp, note->name, pathname,
 775                                 sdt_note__get_addr(note)) < 0)
 776                 goto error;
 777
 778         if (!note->args)
 779                 goto out;
 780
 781         if (note->args) {
 782                 args = argv_split(note->args, &args_count);
 783
 784                 for (i = 0; i < args_count; ++i) {
 785                         if (synthesize_sdt_probe_arg(&buf, i, args[i]) < 0)
 786                                 goto error;
 787                 }
 788         }
 789
 790 out:
 791         ret = strbuf_detach(&buf, NULL);
 792 error:
 793         strbuf_release(&buf);
 794         return ret;
 795 }
 796
 797 int probe_cache__scan_sdt(struct probe_cache *pcache, const char *pathname)
 798 {
 799         struct probe_cache_entry *entry = NULL;
 800         struct list_head sdtlist;
 801         struct sdt_note *note;
 802         char *buf;
 803         char sdtgrp[64];
 804         int ret;
 805
 806         INIT_LIST_HEAD(&sdtlist);
 807         ret = get_sdt_note_list(&sdtlist, pathname);
 808         if (ret < 0) {
 809                 pr_debug4("Failed to get sdt note: %d\n", ret);
 810                 return ret;
 811         }
 812         list_for_each_entry(note, &sdtlist, note_list) {
 813                 ret = snprintf(sdtgrp, 64, "sdt_%s", note->provider);
 814                 if (ret < 0)
 815                         break;
 816                 /* Try to find same-name entry */
 817                 entry = probe_cache__find_by_name(pcache, sdtgrp, note->name);
 818                 if (!entry) {
 819                         entry = probe_cache_entry__new(NULL);
 820                         if (!entry) {
 821                                 ret = -ENOMEM;
 822                                 break;
 823                         }
 824                         entry->sdt = true;
 825                         ret = asprintf(&entry->spev, "%s:%s=%s", sdtgrp,
 826                                         note->name, note->name);
 827                         if (ret < 0)
 828                                 break;
 829                         entry->pev.event = strdup(note->name);
 830                         entry->pev.group = strdup(sdtgrp);
 831                         list_add_tail(&entry->node, &pcache->entries);
 832                 }
 833                 buf = synthesize_sdt_probe_command(note, pathname, sdtgrp);
 834                 if (!buf) {
 835                         ret = -ENOMEM;
 836                         break;
 837                 }
 838
 839                 strlist__add(entry->tevlist, buf);
 840                 free(buf);
 841                 entry = NULL;
 842         }
 843         if (entry) {
 844                 list_del_init(&entry->node);
 845                 probe_cache_entry__delete(entry);
 846         }
 847         cleanup_sdt_note_list(&sdtlist);
 848         return ret;
 849 }
 850 #endif
 851
 852 static int probe_cache_entry__write(struct probe_cache_entry *entry, int fd)
 853 {
 854         struct str_node *snode;
 855         struct stat st;
 856         struct iovec iov[3];
 857         const char *prefix = entry->sdt ? "%" : "#";
 858         int ret;
 859         /* Save stat for rollback */
 860         ret = fstat(fd, &st);
 861         if (ret < 0)
 862                 return ret;
 863
 864         pr_debug("Writing cache: %s%s\n", prefix, entry->spev);
 865         iov[0].iov_base = (void *)prefix; iov[0].iov_len = 1;
 866         iov[1].iov_base = entry->spev; iov[1].iov_len = strlen(entry->spev);
 867         iov[2].iov_base = (void *)"\n"; iov[2].iov_len = 1;
 868         ret = writev(fd, iov, 3);
 869         if (ret < (int)iov[1].iov_len + 2)
 870                 goto rollback;
 871
 872         strlist__for_each_entry(snode, entry->tevlist) {
 873                 iov[0].iov_base = (void *)snode->s;
 874                 iov[0].iov_len = strlen(snode->s);
 875                 iov[1].iov_base = (void *)"\n"; iov[1].iov_len = 1;
 876                 ret = writev(fd, iov, 2);
 877                 if (ret < (int)iov[0].iov_len + 1)
 878                         goto rollback;
 879         }
 880         return 0;
 881
 882 rollback:
 883         /* Rollback to avoid cache file corruption */
 884         if (ret > 0)
 885                 ret = -1;
 886         if (ftruncate(fd, st.st_size) < 0)
 887                 ret = -2;
 888
 889         return ret;
 890 }
 891
 892 int probe_cache__commit(struct probe_cache *pcache)
 893 {
 894         struct probe_cache_entry *entry;
 895         int ret = 0;
 896
 897         /* TBD: if we do not update existing entries, skip it */
 898         ret = lseek(pcache->fd, 0, SEEK_SET);
 899         if (ret < 0)
 900                 goto out;
 901
 902         ret = ftruncate(pcache->fd, 0);
 903         if (ret < 0)
 904                 goto out;
 905
 906         for_each_probe_cache_entry(entry, pcache) {
 907                 ret = probe_cache_entry__write(entry, pcache->fd);
 908                 pr_debug("Cache committed: %d\n", ret);
 909                 if (ret < 0)
 910                         break;
 911         }
 912 out:
 913         return ret;
 914 }
 915
 916 static bool probe_cache_entry__compare(struct probe_cache_entry *entry,
 917                                        struct strfilter *filter)
 918 {
 919         char buf[128], *ptr = entry->spev;
 920
 921         if (entry->pev.event) {
 922                 snprintf(buf, 128, "%s:%s", entry->pev.group, entry->pev.event);
 923                 ptr = buf;
 924         }
 925         return strfilter__compare(filter, ptr);
 926 }
 927
 928 int probe_cache__filter_purge(struct probe_cache *pcache,
 929                               struct strfilter *filter)
 930 {
 931         struct probe_cache_entry *entry, *tmp;
 932
 933         list_for_each_entry_safe(entry, tmp, &pcache->entries, node) {
 934                 if (probe_cache_entry__compare(entry, filter)) {
 935                         pr_info("Removed cached event: %s\n", entry->spev);
 936                         list_del_init(&entry->node);
 937                         probe_cache_entry__delete(entry);
 938                 }
 939         }
 940         return 0;
 941 }
 942
 943 static int probe_cache__show_entries(struct probe_cache *pcache,
 944                                      struct strfilter *filter)
 945 {
 946         struct probe_cache_entry *entry;
 947
 948         for_each_probe_cache_entry(entry, pcache) {
 949                 if (probe_cache_entry__compare(entry, filter))
 950                         printf("%s\n", entry->spev);
 951         }
 952         return 0;
 953 }
 954
 955 /* Show all cached probes */
 956 int probe_cache__show_all_caches(struct strfilter *filter)
 957 {
 958         struct probe_cache *pcache;
 959         struct strlist *bidlist;
 960         struct str_node *nd;
 961         char *buf = strfilter__string(filter);
 962
 963         pr_debug("list cache with filter: %s\n", buf);
 964         free(buf);
 965
 966         bidlist = build_id_cache__list_all(true);
 967         if (!bidlist) {
 968                 pr_debug("Failed to get buildids: %d\n", errno);
 969                 return -EINVAL;
 970         }
 971         strlist__for_each_entry(nd, bidlist) {
 972                 pcache = probe_cache__new(nd->s);
 973                 if (!pcache)
 974                         continue;
 975                 if (!list_empty(&pcache->entries)) {
 976                         buf = build_id_cache__origname(nd->s);
 977                         printf("%s (%s):\n", buf, nd->s);
 978                         free(buf);
 979                         probe_cache__show_entries(pcache, filter);
 980                 }
 981                 probe_cache__delete(pcache);
 982         }
 983         strlist__delete(bidlist);
 984
 985         return 0;
 986 }
 987
 988 enum ftrace_readme {
 989         FTRACE_README_PROBE_TYPE_X = 0,
 990         FTRACE_README_KRETPROBE_OFFSET,
 991         FTRACE_README_END,
 992 };
 993
 994 static struct {
 995         const char *pattern;
 996         bool avail;
 997 } ftrace_readme_table[] = {
 998 #define DEFINE_TYPE(idx, pat)                   \
 999         [idx] = {.pattern = pat, .avail = false}
1000         DEFINE_TYPE(FTRACE_README_PROBE_TYPE_X, "*type: * x8/16/32/64,*"),
1001         DEFINE_TYPE(FTRACE_README_KRETPROBE_OFFSET, "*place (kretprobe): *"),
1002 };
1003
1004 static bool scan_ftrace_readme(enum ftrace_readme type)
1005 {
1006         int fd;
1007         FILE *fp;
1008         char *buf = NULL;
1009         size_t len = 0;
1010         bool ret = false;
1011         static bool scanned = false;
1012
1013         if (scanned)
1014                 goto result;
1015
1016         fd = open_trace_file("README", false);
1017         if (fd < 0)
1018                 return ret;
1019
1020         fp = fdopen(fd, "r");
1021         if (!fp) {
1022                 close(fd);
1023                 return ret;
1024         }
1025
1026         while (getline(&buf, &len, fp) > 0)
1027                 for (enum ftrace_readme i = 0; i < FTRACE_README_END; i++)
1028                         if (!ftrace_readme_table[i].avail)
1029                                 ftrace_readme_table[i].avail =
1030                                         strglobmatch(buf, ftrace_readme_table[i].pattern);
1031         scanned = true;
1032
1033         fclose(fp);
1034         free(buf);
1035
1036 result:
1037         if (type >= FTRACE_README_END)
1038                 return false;
1039
1040         return ftrace_readme_table[type].avail;
1041 }
1042
1043 bool probe_type_is_available(enum probe_type type)
1044 {
1045         if (type >= PROBE_TYPE_END)
1046                 return false;
1047         else if (type == PROBE_TYPE_X)
1048                 return scan_ftrace_readme(FTRACE_README_PROBE_TYPE_X);
1049
1050         return true;
1051 }
1052
1053 bool kretprobe_offset_is_supported(void)
1054 {
1055         return scan_ftrace_readme(FTRACE_README_KRETPROBE_OFFSET);
1056 }