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