tools/perf/util/probe-event.c

   1 /*
   2  * probe-event.c : perf-probe definition to probe_events format converter
   3  *
   4  * Written by Masami Hiramatsu <mhiramat@redhat.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  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  *
  20  */
  21
  22 #define _GNU_SOURCE
  23 #include <sys/utsname.h>
  24 #include <sys/types.h>
  25 #include <sys/stat.h>
  26 #include <fcntl.h>
  27 #include <errno.h>
  28 #include <stdio.h>
  29 #include <unistd.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <stdarg.h>
  33 #include <limits.h>
  34
  35 #undef _GNU_SOURCE
  36 #include "util.h"
  37 #include "event.h"
  38 #include "string.h"
  39 #include "strlist.h"
  40 #include "debug.h"
  41 #include "cache.h"
  42 #include "color.h"
  43 #include "symbol.h"
  44 #include "thread.h"
  45 #include "debugfs.h"
  46 #include "trace-event.h"        /* For __unused */
  47 #include "probe-event.h"
  48 #include "probe-finder.h"
  49
  50 #define MAX_CMDLEN 256
  51 #define MAX_PROBE_ARGS 128
  52 #define PERFPROBE_GROUP "probe"
  53
  54 bool probe_event_dry_run;       /* Dry run flag */
  55
  56 #define semantic_error(msg ...) pr_err("Semantic error :" msg)
  57
  58 /* If there is no space to write, returns -E2BIG. */
  59 static int e_snprintf(char *str, size_t size, const char *format, ...)
  60         __attribute__((format(printf, 3, 4)));
  61
  62 static int e_snprintf(char *str, size_t size, const char *format, ...)
  63 {
  64         int ret;
  65         va_list ap;
  66         va_start(ap, format);
  67         ret = vsnprintf(str, size, format, ap);
  68         va_end(ap);
  69         if (ret >= (int)size)
  70                 ret = -E2BIG;
  71         return ret;
  72 }
  73
  74 static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
  75 static struct machine machine;
  76
  77 /* Initialize symbol maps and path of vmlinux/modules */
  78 static int init_vmlinux(void)
  79 {
  80         int ret;
  81
  82         symbol_conf.sort_by_name = true;
  83         if (symbol_conf.vmlinux_name == NULL)
  84                 symbol_conf.try_vmlinux_path = true;
  85         else
  86                 pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name);
  87         ret = symbol__init();
  88         if (ret < 0) {
  89                 pr_debug("Failed to init symbol map.\n");
  90                 goto out;
  91         }
  92
  93         ret = machine__init(&machine, "", HOST_KERNEL_ID);
  94         if (ret < 0)
  95                 goto out;
  96
  97         if (machine__create_kernel_maps(&machine) < 0) {
  98                 pr_debug("machine__create_kernel_maps() failed.\n");
  99                 goto out;
 100         }
 101 out:
 102         if (ret < 0)
 103                 pr_warning("Failed to init vmlinux path.\n");
 104         return ret;
 105 }
 106
 107 static struct symbol *__find_kernel_function_by_name(const char *name,
 108                                                      struct map **mapp)
 109 {
 110         return machine__find_kernel_function_by_name(&machine, name, mapp,
 111                                                      NULL);
 112 }
 113
 114 const char *kernel_get_module_path(const char *module)
 115 {
 116         struct dso *dso;
 117         struct map *map;
 118         const char *vmlinux_name;
 119
 120         if (module) {
 121                 list_for_each_entry(dso, &machine.kernel_dsos, node) {
 122                         if (strncmp(dso->short_name + 1, module,
 123                                     dso->short_name_len - 2) == 0)
 124                                 goto found;
 125                 }
 126                 pr_debug("Failed to find module %s.\n", module);
 127                 return NULL;
 128         }
 129
 130         map = machine.vmlinux_maps[MAP__FUNCTION];
 131         dso = map->dso;
 132
 133         vmlinux_name = symbol_conf.vmlinux_name;
 134         if (vmlinux_name) {
 135                 if (dso__load_vmlinux(dso, map, vmlinux_name, NULL) <= 0)
 136                         return NULL;
 137         } else {
 138                 if (dso__load_vmlinux_path(dso, map, NULL) <= 0) {
 139                         pr_debug("Failed to load kernel map.\n");
 140                         return NULL;
 141                 }
 142         }
 143 found:
 144         return dso->long_name;
 145 }
 146
 147 #ifdef DWARF_SUPPORT
 148 static int open_vmlinux(const char *module)
 149 {
 150         const char *path = kernel_get_module_path(module);
 151         if (!path) {
 152                 pr_err("Failed to find path of %s module.\n",
 153                        module ?: "kernel");
 154                 return -ENOENT;
 155         }
 156         pr_debug("Try to open %s\n", path);
 157         return open(path, O_RDONLY);
 158 }
 159
 160 /*
 161  * Convert trace point to probe point with debuginfo
 162  * Currently only handles kprobes.
 163  */
 164 static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
 165                                         struct perf_probe_point *pp)
 166 {
 167         struct symbol *sym;
 168         struct map *map;
 169         u64 addr;
 170         int ret = -ENOENT;
 171
 172         sym = __find_kernel_function_by_name(tp->symbol, &map);
 173         if (sym) {
 174                 addr = map->unmap_ip(map, sym->start + tp->offset);
 175                 pr_debug("try to find %s+%ld@%llx\n", tp->symbol,
 176                          tp->offset, addr);
 177                 ret = find_perf_probe_point((unsigned long)addr, pp);
 178         }
 179         if (ret <= 0) {
 180                 pr_debug("Failed to find corresponding probes from "
 181                          "debuginfo. Use kprobe event information.\n");
 182                 pp->function = strdup(tp->symbol);
 183                 if (pp->function == NULL)
 184                         return -ENOMEM;
 185                 pp->offset = tp->offset;
 186         }
 187         pp->retprobe = tp->retprobe;
 188
 189         return 0;
 190 }
 191
 192 /* Try to find perf_probe_event with debuginfo */
 193 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
 194                                            struct probe_trace_event **tevs,
 195                                            int max_tevs, const char *module)
 196 {
 197         bool need_dwarf = perf_probe_event_need_dwarf(pev);
 198         int fd, ntevs;
 199
 200         fd = open_vmlinux(module);
 201         if (fd < 0) {
 202                 if (need_dwarf) {
 203                         pr_warning("Failed to open debuginfo file.\n");
 204                         return fd;
 205                 }
 206                 pr_debug("Could not open vmlinux. Try to use symbols.\n");
 207                 return 0;
 208         }
 209
 210         /* Searching trace events corresponding to probe event */
 211         ntevs = find_probe_trace_events(fd, pev, tevs, max_tevs);
 212         close(fd);
 213
 214         if (ntevs > 0) {        /* Succeeded to find trace events */
 215                 pr_debug("find %d probe_trace_events.\n", ntevs);
 216                 return ntevs;
 217         }
 218
 219         if (ntevs == 0) {       /* No error but failed to find probe point. */
 220                 pr_warning("Probe point '%s' not found.\n",
 221                            synthesize_perf_probe_point(&pev->point));
 222                 return -ENOENT;
 223         }
 224         /* Error path : ntevs < 0 */
 225         pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
 226         if (ntevs == -EBADF) {
 227                 pr_warning("Warning: No dwarf info found in the vmlinux - "
 228                         "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n");
 229                 if (!need_dwarf) {
 230                         pr_debug("Trying to use symbols.\n");
 231                         return 0;
 232                 }
 233         }
 234         return ntevs;
 235 }
 236
 237 /*
 238  * Find a src file from a DWARF tag path. Prepend optional source path prefix
 239  * and chop off leading directories that do not exist. Result is passed back as
 240  * a newly allocated path on success.
 241  * Return 0 if file was found and readable, -errno otherwise.
 242  */
 243 static int get_real_path(const char *raw_path, const char *comp_dir,
 244                          char **new_path)
 245 {
 246         const char *prefix = symbol_conf.source_prefix;
 247
 248         if (!prefix) {
 249                 if (raw_path[0] != '/' && comp_dir)
 250                         /* If not an absolute path, try to use comp_dir */
 251                         prefix = comp_dir;
 252                 else {
 253                         if (access(raw_path, R_OK) == 0) {
 254                                 *new_path = strdup(raw_path);
 255                                 return 0;
 256                         } else
 257                                 return -errno;
 258                 }
 259         }
 260
 261         *new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
 262         if (!*new_path)
 263                 return -ENOMEM;
 264
 265         for (;;) {
 266                 sprintf(*new_path, "%s/%s", prefix, raw_path);
 267
 268                 if (access(*new_path, R_OK) == 0)
 269                         return 0;
 270
 271                 if (!symbol_conf.source_prefix)
 272                         /* In case of searching comp_dir, don't retry */
 273                         return -errno;
 274
 275                 switch (errno) {
 276                 case ENAMETOOLONG:
 277                 case ENOENT:
 278                 case EROFS:
 279                 case EFAULT:
 280                         raw_path = strchr(++raw_path, '/');
 281                         if (!raw_path) {
 282                                 free(*new_path);
 283                                 *new_path = NULL;
 284                                 return -ENOENT;
 285                         }
 286                         continue;
 287
 288                 default:
 289                         free(*new_path);
 290                         *new_path = NULL;
 291                         return -errno;
 292                 }
 293         }
 294 }
 295
 296 #define LINEBUF_SIZE 256
 297 #define NR_ADDITIONAL_LINES 2
 298
 299 static int __show_one_line(FILE *fp, int l, bool skip, bool show_num)
 300 {
 301         char buf[LINEBUF_SIZE];
 302         const char *color = show_num ? "" : PERF_COLOR_BLUE;
 303         const char *prefix = NULL;
 304
 305         do {
 306                 if (fgets(buf, LINEBUF_SIZE, fp) == NULL)
 307                         goto error;
 308                 if (skip)
 309                         continue;
 310                 if (!prefix) {
 311                         prefix = show_num ? "%7d  " : "         ";
 312                         color_fprintf(stdout, color, prefix, l);
 313                 }
 314                 color_fprintf(stdout, color, "%s", buf);
 315
 316         } while (strchr(buf, '\n') == NULL);
 317
 318         return 1;
 319 error:
 320         if (ferror(fp)) {
 321                 pr_warning("File read error: %s\n", strerror(errno));
 322                 return -1;
 323         }
 324         return 0;
 325 }
 326
 327 static int _show_one_line(FILE *fp, int l, bool skip, bool show_num)
 328 {
 329         int rv = __show_one_line(fp, l, skip, show_num);
 330         if (rv == 0) {
 331                 pr_warning("Source file is shorter than expected.\n");
 332                 rv = -1;
 333         }
 334         return rv;
 335 }
 336
 337 #define show_one_line_with_num(f,l)     _show_one_line(f,l,false,true)
 338 #define show_one_line(f,l)              _show_one_line(f,l,false,false)
 339 #define skip_one_line(f,l)              _show_one_line(f,l,true,false)
 340 #define show_one_line_or_eof(f,l)       __show_one_line(f,l,false,false)
 341
 342 /*
 343  * Show line-range always requires debuginfo to find source file and
 344  * line number.
 345  */
 346 int show_line_range(struct line_range *lr, const char *module)
 347 {
 348         int l = 1;
 349         struct line_node *ln;
 350         FILE *fp;
 351         int fd, ret;
 352         char *tmp;
 353
 354         /* Search a line range */
 355         ret = init_vmlinux();
 356         if (ret < 0)
 357                 return ret;
 358
 359         fd = open_vmlinux(module);
 360         if (fd < 0) {
 361                 pr_warning("Failed to open debuginfo file.\n");
 362                 return fd;
 363         }
 364
 365         ret = find_line_range(fd, lr);
 366         close(fd);
 367         if (ret == 0) {
 368                 pr_warning("Specified source line is not found.\n");
 369                 return -ENOENT;
 370         } else if (ret < 0) {
 371                 pr_warning("Debuginfo analysis failed. (%d)\n", ret);
 372                 return ret;
 373         }
 374
 375         /* Convert source file path */
 376         tmp = lr->path;
 377         ret = get_real_path(tmp, lr->comp_dir, &lr->path);
 378         free(tmp);      /* Free old path */
 379         if (ret < 0) {
 380                 pr_warning("Failed to find source file. (%d)\n", ret);
 381                 return ret;
 382         }
 383
 384         setup_pager();
 385
 386         if (lr->function)
 387                 fprintf(stdout, "<%s:%d>\n", lr->function,
 388                         lr->start - lr->offset);
 389         else
 390                 fprintf(stdout, "<%s:%d>\n", lr->path, lr->start);
 391
 392         fp = fopen(lr->path, "r");
 393         if (fp == NULL) {
 394                 pr_warning("Failed to open %s: %s\n", lr->path,
 395                            strerror(errno));
 396                 return -errno;
 397         }
 398         /* Skip to starting line number */
 399         while (l < lr->start) {
 400                 ret = skip_one_line(fp, l++);
 401                 if (ret < 0)
 402                         goto end;
 403         }
 404
 405         list_for_each_entry(ln, &lr->line_list, list) {
 406                 for (; ln->line > l; l++) {
 407                         ret = show_one_line(fp, l - lr->offset);
 408                         if (ret < 0)
 409                                 goto end;
 410                 }
 411                 ret = show_one_line_with_num(fp, l++ - lr->offset);
 412                 if (ret < 0)
 413                         goto end;
 414         }
 415
 416         if (lr->end == INT_MAX)
 417                 lr->end = l + NR_ADDITIONAL_LINES;
 418         while (l <= lr->end) {
 419                 ret = show_one_line_or_eof(fp, l++ - lr->offset);
 420                 if (ret <= 0)
 421                         break;
 422         }
 423 end:
 424         fclose(fp);
 425         return ret;
 426 }
 427
 428 static int show_available_vars_at(int fd, struct perf_probe_event *pev,
 429                                   int max_vls, bool externs)
 430 {
 431         char *buf;
 432         int ret, i;
 433         struct str_node *node;
 434         struct variable_list *vls = NULL, *vl;
 435
 436         buf = synthesize_perf_probe_point(&pev->point);
 437         if (!buf)
 438                 return -EINVAL;
 439         pr_debug("Searching variables at %s\n", buf);
 440
 441         ret = find_available_vars_at(fd, pev, &vls, max_vls, externs);
 442         if (ret > 0) {
 443                 /* Some variables were found */
 444                 fprintf(stdout, "Available variables at %s\n", buf);
 445                 for (i = 0; i < ret; i++) {
 446                         vl = &vls[i];
 447                         /*
 448                          * A probe point might be converted to
 449                          * several trace points.
 450                          */
 451                         fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol,
 452                                 vl->point.offset);
 453                         free(vl->point.symbol);
 454                         if (vl->vars) {
 455                                 strlist__for_each(node, vl->vars)
 456                                         fprintf(stdout, "\t\t%s\n", node->s);
 457                                 strlist__delete(vl->vars);
 458                         } else
 459                                 fprintf(stdout, "(No variables)\n");
 460                 }
 461                 free(vls);
 462         } else
 463                 pr_err("Failed to find variables at %s (%d)\n", buf, ret);
 464
 465         free(buf);
 466         return ret;
 467 }
 468
 469 /* Show available variables on given probe point */
 470 int show_available_vars(struct perf_probe_event *pevs, int npevs,
 471                         int max_vls, const char *module, bool externs)
 472 {
 473         int i, fd, ret = 0;
 474
 475         ret = init_vmlinux();
 476         if (ret < 0)
 477                 return ret;
 478
 479         fd = open_vmlinux(module);
 480         if (fd < 0) {
 481                 pr_warning("Failed to open debug information file.\n");
 482                 return fd;
 483         }
 484
 485         setup_pager();
 486
 487         for (i = 0; i < npevs && ret >= 0; i++)
 488                 ret = show_available_vars_at(fd, &pevs[i], max_vls, externs);
 489
 490         close(fd);
 491         return ret;
 492 }
 493
 494 #else   /* !DWARF_SUPPORT */
 495
 496 static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
 497                                         struct perf_probe_point *pp)
 498 {
 499         struct symbol *sym;
 500
 501         sym = __find_kernel_function_by_name(tp->symbol, NULL);
 502         if (!sym) {
 503                 pr_err("Failed to find symbol %s in kernel.\n", tp->symbol);
 504                 return -ENOENT;
 505         }
 506         pp->function = strdup(tp->symbol);
 507         if (pp->function == NULL)
 508                 return -ENOMEM;
 509         pp->offset = tp->offset;
 510         pp->retprobe = tp->retprobe;
 511
 512         return 0;
 513 }
 514
 515 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
 516                                 struct probe_trace_event **tevs __unused,
 517                                 int max_tevs __unused, const char *mod __unused)
 518 {
 519         if (perf_probe_event_need_dwarf(pev)) {
 520                 pr_warning("Debuginfo-analysis is not supported.\n");
 521                 return -ENOSYS;
 522         }
 523         return 0;
 524 }
 525
 526 int show_line_range(struct line_range *lr __unused, const char *module __unused)
 527 {
 528         pr_warning("Debuginfo-analysis is not supported.\n");
 529         return -ENOSYS;
 530 }
 531
 532 int show_available_vars(struct perf_probe_event *pevs __unused,
 533                         int npevs __unused, int max_vls __unused,
 534                         const char *module __unused, bool externs __unused)
 535 {
 536         pr_warning("Debuginfo-analysis is not supported.\n");
 537         return -ENOSYS;
 538 }
 539 #endif
 540
 541 static int parse_line_num(char **ptr, int *val, const char *what)
 542 {
 543         const char *start = *ptr;
 544
 545         errno = 0;
 546         *val = strtol(*ptr, ptr, 0);
 547         if (errno || *ptr == start) {
 548                 semantic_error("'%s' is not a valid number.\n", what);
 549                 return -EINVAL;
 550         }
 551         return 0;
 552 }
 553
 554 /*
 555  * Stuff 'lr' according to the line range described by 'arg'.
 556  * The line range syntax is described by:
 557  *
 558  *         SRC[:SLN[+NUM|-ELN]]
 559  *         FNC[:SLN[+NUM|-ELN]]
 560  */
 561 int parse_line_range_desc(const char *arg, struct line_range *lr)
 562 {
 563         char *range, *name = strdup(arg);
 564         int err;
 565
 566         if (!name)
 567                 return -ENOMEM;
 568
 569         lr->start = 0;
 570         lr->end = INT_MAX;
 571
 572         range = strchr(name, ':');
 573         if (range) {
 574                 *range++ = '\0';
 575
 576                 err = parse_line_num(&range, &lr->start, "start line");
 577                 if (err)
 578                         goto err;
 579
 580                 if (*range == '+' || *range == '-') {
 581                         const char c = *range++;
 582
 583                         err = parse_line_num(&range, &lr->end, "end line");
 584                         if (err)
 585                                 goto err;
 586
 587                         if (c == '+') {
 588                                 lr->end += lr->start;
 589                                 /*
 590                                  * Adjust the number of lines here.
 591                                  * If the number of lines == 1, the
 592                                  * the end of line should be equal to
 593                                  * the start of line.
 594                                  */
 595                                 lr->end--;
 596                         }
 597                 }
 598
 599                 pr_debug("Line range is %d to %d\n", lr->start, lr->end);
 600
 601                 err = -EINVAL;
 602                 if (lr->start > lr->end) {
 603                         semantic_error("Start line must be smaller"
 604                                        " than end line.\n");
 605                         goto err;
 606                 }
 607                 if (*range != '\0') {
 608                         semantic_error("Tailing with invalid str '%s'.\n", range);
 609                         goto err;
 610                 }
 611         }
 612
 613         if (strchr(name, '.'))
 614                 lr->file = name;
 615         else
 616                 lr->function = name;
 617
 618         return 0;
 619 err:
 620         free(name);
 621         return err;
 622 }
 623
 624 /* Check the name is good for event/group */
 625 static bool check_event_name(const char *name)
 626 {
 627         if (!isalpha(*name) && *name != '_')
 628                 return false;
 629         while (*++name != '\0') {
 630                 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
 631                         return false;
 632         }
 633         return true;
 634 }
 635
 636 /* Parse probepoint definition. */
 637 static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
 638 {
 639         struct perf_probe_point *pp = &pev->point;
 640         char *ptr, *tmp;
 641         char c, nc = 0;
 642         /*
 643          * <Syntax>
 644          * perf probe [EVENT=]SRC[:LN|;PTN]
 645          * perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
 646          *
 647          * TODO:Group name support
 648          */
 649
 650         ptr = strpbrk(arg, ";=@+%");
 651         if (ptr && *ptr == '=') {       /* Event name */
 652                 *ptr = '\0';
 653                 tmp = ptr + 1;
 654                 if (strchr(arg, ':')) {
 655                         semantic_error("Group name is not supported yet.\n");
 656                         return -ENOTSUP;
 657                 }
 658                 if (!check_event_name(arg)) {
 659                         semantic_error("%s is bad for event name -it must "
 660                                        "follow C symbol-naming rule.\n", arg);
 661                         return -EINVAL;
 662                 }
 663                 pev->event = strdup(arg);
 664                 if (pev->event == NULL)
 665                         return -ENOMEM;
 666                 pev->group = NULL;
 667                 arg = tmp;
 668         }
 669
 670         ptr = strpbrk(arg, ";:+@%");
 671         if (ptr) {
 672                 nc = *ptr;
 673                 *ptr++ = '\0';
 674         }
 675
 676         tmp = strdup(arg);
 677         if (tmp == NULL)
 678                 return -ENOMEM;
 679
 680         /* Check arg is function or file and copy it */
 681         if (strchr(tmp, '.'))   /* File */
 682                 pp->file = tmp;
 683         else                    /* Function */
 684                 pp->function = tmp;
 685
 686         /* Parse other options */
 687         while (ptr) {
 688                 arg = ptr;
 689                 c = nc;
 690                 if (c == ';') { /* Lazy pattern must be the last part */
 691                         pp->lazy_line = strdup(arg);
 692                         if (pp->lazy_line == NULL)
 693                                 return -ENOMEM;
 694                         break;
 695                 }
 696                 ptr = strpbrk(arg, ";:+@%");
 697                 if (ptr) {
 698                         nc = *ptr;
 699                         *ptr++ = '\0';
 700                 }
 701                 switch (c) {
 702                 case ':':       /* Line number */
 703                         pp->line = strtoul(arg, &tmp, 0);
 704                         if (*tmp != '\0') {
 705                                 semantic_error("There is non-digit char"
 706                                                " in line number.\n");
 707                                 return -EINVAL;
 708                         }
 709                         break;
 710                 case '+':       /* Byte offset from a symbol */
 711                         pp->offset = strtoul(arg, &tmp, 0);
 712                         if (*tmp != '\0') {
 713                                 semantic_error("There is non-digit character"
 714                                                 " in offset.\n");
 715                                 return -EINVAL;
 716                         }
 717                         break;
 718                 case '@':       /* File name */
 719                         if (pp->file) {
 720                                 semantic_error("SRC@SRC is not allowed.\n");
 721                                 return -EINVAL;
 722                         }
 723                         pp->file = strdup(arg);
 724                         if (pp->file == NULL)
 725                                 return -ENOMEM;
 726                         break;
 727                 case '%':       /* Probe places */
 728                         if (strcmp(arg, "return") == 0) {
 729                                 pp->retprobe = 1;
 730                         } else {        /* Others not supported yet */
 731                                 semantic_error("%%%s is not supported.\n", arg);
 732                                 return -ENOTSUP;
 733                         }
 734                         break;
 735                 default:        /* Buggy case */
 736                         pr_err("This program has a bug at %s:%d.\n",
 737                                 __FILE__, __LINE__);
 738                         return -ENOTSUP;
 739                         break;
 740                 }
 741         }
 742
 743         /* Exclusion check */
 744         if (pp->lazy_line && pp->line) {
 745                 semantic_error("Lazy pattern can't be used with"
 746                                " line number.\n");
 747                 return -EINVAL;
 748         }
 749
 750         if (pp->lazy_line && pp->offset) {
 751                 semantic_error("Lazy pattern can't be used with offset.\n");
 752                 return -EINVAL;
 753         }
 754
 755         if (pp->line && pp->offset) {
 756                 semantic_error("Offset can't be used with line number.\n");
 757                 return -EINVAL;
 758         }
 759
 760         if (!pp->line && !pp->lazy_line && pp->file && !pp->function) {
 761                 semantic_error("File always requires line number or "
 762                                "lazy pattern.\n");
 763                 return -EINVAL;
 764         }
 765
 766         if (pp->offset && !pp->function) {
 767                 semantic_error("Offset requires an entry function.\n");
 768                 return -EINVAL;
 769         }
 770
 771         if (pp->retprobe && !pp->function) {
 772                 semantic_error("Return probe requires an entry function.\n");
 773                 return -EINVAL;
 774         }
 775
 776         if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) {
 777                 semantic_error("Offset/Line/Lazy pattern can't be used with "
 778                                "return probe.\n");
 779                 return -EINVAL;
 780         }
 781
 782         pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n",
 783                  pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
 784                  pp->lazy_line);
 785         return 0;
 786 }
 787
 788 /* Parse perf-probe event argument */
 789 static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
 790 {
 791         char *tmp, *goodname;
 792         struct perf_probe_arg_field **fieldp;
 793
 794         pr_debug("parsing arg: %s into ", str);
 795
 796         tmp = strchr(str, '=');
 797         if (tmp) {
 798                 arg->name = strndup(str, tmp - str);
 799                 if (arg->name == NULL)
 800                         return -ENOMEM;
 801                 pr_debug("name:%s ", arg->name);
 802                 str = tmp + 1;
 803         }
 804
 805         tmp = strchr(str, ':');
 806         if (tmp) {      /* Type setting */
 807                 *tmp = '\0';
 808                 arg->type = strdup(tmp + 1);
 809                 if (arg->type == NULL)
 810                         return -ENOMEM;
 811                 pr_debug("type:%s ", arg->type);
 812         }
 813
 814         tmp = strpbrk(str, "-.[");
 815         if (!is_c_varname(str) || !tmp) {
 816                 /* A variable, register, symbol or special value */
 817                 arg->var = strdup(str);
 818                 if (arg->var == NULL)
 819                         return -ENOMEM;
 820                 pr_debug("%s\n", arg->var);
 821                 return 0;
 822         }
 823
 824         /* Structure fields or array element */
 825         arg->var = strndup(str, tmp - str);
 826         if (arg->var == NULL)
 827                 return -ENOMEM;
 828         goodname = arg->var;
 829         pr_debug("%s, ", arg->var);
 830         fieldp = &arg->field;
 831
 832         do {
 833                 *fieldp = zalloc(sizeof(struct perf_probe_arg_field));
 834                 if (*fieldp == NULL)
 835                         return -ENOMEM;
 836                 if (*tmp == '[') {      /* Array */
 837                         str = tmp;
 838                         (*fieldp)->index = strtol(str + 1, &tmp, 0);
 839                         (*fieldp)->ref = true;
 840                         if (*tmp != ']' || tmp == str + 1) {
 841                                 semantic_error("Array index must be a"
 842                                                 " number.\n");
 843                                 return -EINVAL;
 844                         }
 845                         tmp++;
 846                         if (*tmp == '\0')
 847                                 tmp = NULL;
 848                 } else {                /* Structure */
 849                         if (*tmp == '.') {
 850                                 str = tmp + 1;
 851                                 (*fieldp)->ref = false;
 852                         } else if (tmp[1] == '>') {
 853                                 str = tmp + 2;
 854                                 (*fieldp)->ref = true;
 855                         } else {
 856                                 semantic_error("Argument parse error: %s\n",
 857                                                str);
 858                                 return -EINVAL;
 859                         }
 860                         tmp = strpbrk(str, "-.[");
 861                 }
 862                 if (tmp) {
 863                         (*fieldp)->name = strndup(str, tmp - str);
 864                         if ((*fieldp)->name == NULL)
 865                                 return -ENOMEM;
 866                         if (*str != '[')
 867                                 goodname = (*fieldp)->name;
 868                         pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref);
 869                         fieldp = &(*fieldp)->next;
 870                 }
 871         } while (tmp);
 872         (*fieldp)->name = strdup(str);
 873         if ((*fieldp)->name == NULL)
 874                 return -ENOMEM;
 875         if (*str != '[')
 876                 goodname = (*fieldp)->name;
 877         pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref);
 878
 879         /* If no name is specified, set the last field name (not array index)*/
 880         if (!arg->name) {
 881                 arg->name = strdup(goodname);
 882                 if (arg->name == NULL)
 883                         return -ENOMEM;
 884         }
 885         return 0;
 886 }
 887
 888 /* Parse perf-probe event command */
 889 int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
 890 {
 891         char **argv;
 892         int argc, i, ret = 0;
 893
 894         argv = argv_split(cmd, &argc);
 895         if (!argv) {
 896                 pr_debug("Failed to split arguments.\n");
 897                 return -ENOMEM;
 898         }
 899         if (argc - 1 > MAX_PROBE_ARGS) {
 900                 semantic_error("Too many probe arguments (%d).\n", argc - 1);
 901                 ret = -ERANGE;
 902                 goto out;
 903         }
 904         /* Parse probe point */
 905         ret = parse_perf_probe_point(argv[0], pev);
 906         if (ret < 0)
 907                 goto out;
 908
 909         /* Copy arguments and ensure return probe has no C argument */
 910         pev->nargs = argc - 1;
 911         pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
 912         if (pev->args == NULL) {
 913                 ret = -ENOMEM;
 914                 goto out;
 915         }
 916         for (i = 0; i < pev->nargs && ret >= 0; i++) {
 917                 ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
 918                 if (ret >= 0 &&
 919                     is_c_varname(pev->args[i].var) && pev->point.retprobe) {
 920                         semantic_error("You can't specify local variable for"
 921                                        " kretprobe.\n");
 922                         ret = -EINVAL;
 923                 }
 924         }
 925 out:
 926         argv_free(argv);
 927
 928         return ret;
 929 }
 930
 931 /* Return true if this perf_probe_event requires debuginfo */
 932 bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
 933 {
 934         int i;
 935
 936         if (pev->point.file || pev->point.line || pev->point.lazy_line)
 937                 return true;
 938
 939         for (i = 0; i < pev->nargs; i++)
 940                 if (is_c_varname(pev->args[i].var))
 941                         return true;
 942
 943         return false;
 944 }
 945
 946 /* Parse probe_events event into struct probe_point */
 947 static int parse_probe_trace_command(const char *cmd,
 948                                         struct probe_trace_event *tev)
 949 {
 950         struct probe_trace_point *tp = &tev->point;
 951         char pr;
 952         char *p;
 953         int ret, i, argc;
 954         char **argv;
 955
 956         pr_debug("Parsing probe_events: %s\n", cmd);
 957         argv = argv_split(cmd, &argc);
 958         if (!argv) {
 959                 pr_debug("Failed to split arguments.\n");
 960                 return -ENOMEM;
 961         }
 962         if (argc < 2) {
 963                 semantic_error("Too few probe arguments.\n");
 964                 ret = -ERANGE;
 965                 goto out;
 966         }
 967
 968         /* Scan event and group name. */
 969         ret = sscanf(argv[0], "%c:%a[^/ \t]/%a[^ \t]",
 970                      &pr, (float *)(void *)&tev->group,
 971                      (float *)(void *)&tev->event);
 972         if (ret != 3) {
 973                 semantic_error("Failed to parse event name: %s\n", argv[0]);
 974                 ret = -EINVAL;
 975                 goto out;
 976         }
 977         pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr);
 978
 979         tp->retprobe = (pr == 'r');
 980
 981         /* Scan function name and offset */
 982         ret = sscanf(argv[1], "%a[^+]+%lu", (float *)(void *)&tp->symbol,
 983                      &tp->offset);
 984         if (ret == 1)
 985                 tp->offset = 0;
 986
 987         tev->nargs = argc - 2;
 988         tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
 989         if (tev->args == NULL) {
 990                 ret = -ENOMEM;
 991                 goto out;
 992         }
 993         for (i = 0; i < tev->nargs; i++) {
 994                 p = strchr(argv[i + 2], '=');
 995                 if (p)  /* We don't need which register is assigned. */
 996                         *p++ = '\0';
 997                 else
 998                         p = argv[i + 2];
 999                 tev->args[i].name = strdup(argv[i + 2]);
1000                 /* TODO: parse regs and offset */
1001                 tev->args[i].value = strdup(p);
1002                 if (tev->args[i].name == NULL || tev->args[i].value == NULL) {
1003                         ret = -ENOMEM;
1004                         goto out;
1005                 }
1006         }
1007         ret = 0;
1008 out:
1009         argv_free(argv);
1010         return ret;
1011 }
1012
1013 /* Compose only probe arg */
1014 int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len)
1015 {
1016         struct perf_probe_arg_field *field = pa->field;
1017         int ret;
1018         char *tmp = buf;
1019
1020         if (pa->name && pa->var)
1021                 ret = e_snprintf(tmp, len, "%s=%s", pa->name, pa->var);
1022         else
1023                 ret = e_snprintf(tmp, len, "%s", pa->name ? pa->name : pa->var);
1024         if (ret <= 0)
1025                 goto error;
1026         tmp += ret;
1027         len -= ret;
1028
1029         while (field) {
1030                 if (field->name[0] == '[')
1031                         ret = e_snprintf(tmp, len, "%s", field->name);
1032                 else
1033                         ret = e_snprintf(tmp, len, "%s%s",
1034                                          field->ref ? "->" : ".", field->name);
1035                 if (ret <= 0)
1036                         goto error;
1037                 tmp += ret;
1038                 len -= ret;
1039                 field = field->next;
1040         }
1041
1042         if (pa->type) {
1043                 ret = e_snprintf(tmp, len, ":%s", pa->type);
1044                 if (ret <= 0)
1045                         goto error;
1046                 tmp += ret;
1047                 len -= ret;
1048         }
1049
1050         return tmp - buf;
1051 error:
1052         pr_debug("Failed to synthesize perf probe argument: %s\n",
1053                  strerror(-ret));
1054         return ret;
1055 }
1056
1057 /* Compose only probe point (not argument) */
1058 static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
1059 {
1060         char *buf, *tmp;
1061         char offs[32] = "", line[32] = "", file[32] = "";
1062         int ret, len;
1063
1064         buf = zalloc(MAX_CMDLEN);
1065         if (buf == NULL) {
1066                 ret = -ENOMEM;
1067                 goto error;
1068         }
1069         if (pp->offset) {
1070                 ret = e_snprintf(offs, 32, "+%lu", pp->offset);
1071                 if (ret <= 0)
1072                         goto error;
1073         }
1074         if (pp->line) {
1075                 ret = e_snprintf(line, 32, ":%d", pp->line);
1076                 if (ret <= 0)
1077                         goto error;
1078         }
1079         if (pp->file) {
1080                 tmp = pp->file;
1081                 len = strlen(tmp);
1082                 if (len > 30) {
1083                         tmp = strchr(pp->file + len - 30, '/');
1084                         tmp = tmp ? tmp + 1 : pp->file + len - 30;
1085                 }
1086                 ret = e_snprintf(file, 32, "@%s", tmp);
1087                 if (ret <= 0)
1088                         goto error;
1089         }
1090
1091         if (pp->function)
1092                 ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
1093                                  offs, pp->retprobe ? "%return" : "", line,
1094                                  file);
1095         else
1096                 ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);
1097         if (ret <= 0)
1098                 goto error;
1099
1100         return buf;
1101 error:
1102         pr_debug("Failed to synthesize perf probe point: %s\n",
1103                  strerror(-ret));
1104         if (buf)
1105                 free(buf);
1106         return NULL;
1107 }
1108
1109 #if 0
1110 char *synthesize_perf_probe_command(struct perf_probe_event *pev)
1111 {
1112         char *buf;
1113         int i, len, ret;
1114
1115         buf = synthesize_perf_probe_point(&pev->point);
1116         if (!buf)
1117                 return NULL;
1118
1119         len = strlen(buf);
1120         for (i = 0; i < pev->nargs; i++) {
1121                 ret = e_snprintf(&buf[len], MAX_CMDLEN - len, " %s",
1122                                  pev->args[i].name);
1123                 if (ret <= 0) {
1124                         free(buf);
1125                         return NULL;
1126                 }
1127                 len += ret;
1128         }
1129
1130         return buf;
1131 }
1132 #endif
1133
1134 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
1135                                              char **buf, size_t *buflen,
1136                                              int depth)
1137 {
1138         int ret;
1139         if (ref->next) {
1140                 depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
1141                                                          buflen, depth + 1);
1142                 if (depth < 0)
1143                         goto out;
1144         }
1145
1146         ret = e_snprintf(*buf, *buflen, "%+ld(", ref->offset);
1147         if (ret < 0)
1148                 depth = ret;
1149         else {
1150                 *buf += ret;
1151                 *buflen -= ret;
1152         }
1153 out:
1154         return depth;
1155
1156 }
1157
1158 static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
1159                                        char *buf, size_t buflen)
1160 {
1161         struct probe_trace_arg_ref *ref = arg->ref;
1162         int ret, depth = 0;
1163         char *tmp = buf;
1164
1165         /* Argument name or separator */
1166         if (arg->name)
1167                 ret = e_snprintf(buf, buflen, " %s=", arg->name);
1168         else
1169                 ret = e_snprintf(buf, buflen, " ");
1170         if (ret < 0)
1171                 return ret;
1172         buf += ret;
1173         buflen -= ret;
1174
1175         /* Special case: @XXX */
1176         if (arg->value[0] == '@' && arg->ref)
1177                         ref = ref->next;
1178
1179         /* Dereferencing arguments */
1180         if (ref) {
1181                 depth = __synthesize_probe_trace_arg_ref(ref, &buf,
1182                                                           &buflen, 1);
1183                 if (depth < 0)
1184                         return depth;
1185         }
1186
1187         /* Print argument value */
1188         if (arg->value[0] == '@' && arg->ref)
1189                 ret = e_snprintf(buf, buflen, "%s%+ld", arg->value,
1190                                  arg->ref->offset);
1191         else
1192                 ret = e_snprintf(buf, buflen, "%s", arg->value);
1193         if (ret < 0)
1194                 return ret;
1195         buf += ret;
1196         buflen -= ret;
1197
1198         /* Closing */
1199         while (depth--) {
1200                 ret = e_snprintf(buf, buflen, ")");
1201                 if (ret < 0)
1202                         return ret;
1203                 buf += ret;
1204                 buflen -= ret;
1205         }
1206         /* Print argument type */
1207         if (arg->type) {
1208                 ret = e_snprintf(buf, buflen, ":%s", arg->type);
1209                 if (ret <= 0)
1210                         return ret;
1211                 buf += ret;
1212         }
1213
1214         return buf - tmp;
1215 }
1216
1217 char *synthesize_probe_trace_command(struct probe_trace_event *tev)
1218 {
1219         struct probe_trace_point *tp = &tev->point;
1220         char *buf;
1221         int i, len, ret;
1222
1223         buf = zalloc(MAX_CMDLEN);
1224         if (buf == NULL)
1225                 return NULL;
1226
1227         len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s+%lu",
1228                          tp->retprobe ? 'r' : 'p',
1229                          tev->group, tev->event,
1230                          tp->symbol, tp->offset);
1231         if (len <= 0)
1232                 goto error;
1233
1234         for (i = 0; i < tev->nargs; i++) {
1235                 ret = synthesize_probe_trace_arg(&tev->args[i], buf + len,
1236                                                   MAX_CMDLEN - len);
1237                 if (ret <= 0)
1238                         goto error;
1239                 len += ret;
1240         }
1241
1242         return buf;
1243 error:
1244         free(buf);
1245         return NULL;
1246 }
1247
1248 static int convert_to_perf_probe_event(struct probe_trace_event *tev,
1249                                        struct perf_probe_event *pev)
1250 {
1251         char buf[64] = "";
1252         int i, ret;
1253
1254         /* Convert event/group name */
1255         pev->event = strdup(tev->event);
1256         pev->group = strdup(tev->group);
1257         if (pev->event == NULL || pev->group == NULL)
1258                 return -ENOMEM;
1259
1260         /* Convert trace_point to probe_point */
1261         ret = kprobe_convert_to_perf_probe(&tev->point, &pev->point);
1262         if (ret < 0)
1263                 return ret;
1264
1265         /* Convert trace_arg to probe_arg */
1266         pev->nargs = tev->nargs;
1267         pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
1268         if (pev->args == NULL)
1269                 return -ENOMEM;
1270         for (i = 0; i < tev->nargs && ret >= 0; i++) {
1271                 if (tev->args[i].name)
1272                         pev->args[i].name = strdup(tev->args[i].name);
1273                 else {
1274                         ret = synthesize_probe_trace_arg(&tev->args[i],
1275                                                           buf, 64);
1276                         pev->args[i].name = strdup(buf);
1277                 }
1278                 if (pev->args[i].name == NULL && ret >= 0)
1279                         ret = -ENOMEM;
1280         }
1281
1282         if (ret < 0)
1283                 clear_perf_probe_event(pev);
1284
1285         return ret;
1286 }
1287
1288 void clear_perf_probe_event(struct perf_probe_event *pev)
1289 {
1290         struct perf_probe_point *pp = &pev->point;
1291         struct perf_probe_arg_field *field, *next;
1292         int i;
1293
1294         if (pev->event)
1295                 free(pev->event);
1296         if (pev->group)
1297                 free(pev->group);
1298         if (pp->file)
1299                 free(pp->file);
1300         if (pp->function)
1301                 free(pp->function);
1302         if (pp->lazy_line)
1303                 free(pp->lazy_line);
1304         for (i = 0; i < pev->nargs; i++) {
1305                 if (pev->args[i].name)
1306                         free(pev->args[i].name);
1307                 if (pev->args[i].var)
1308                         free(pev->args[i].var);
1309                 if (pev->args[i].type)
1310                         free(pev->args[i].type);
1311                 field = pev->args[i].field;
1312                 while (field) {
1313                         next = field->next;
1314                         if (field->name)
1315                                 free(field->name);
1316                         free(field);
1317                         field = next;
1318                 }
1319         }
1320         if (pev->args)
1321                 free(pev->args);
1322         memset(pev, 0, sizeof(*pev));
1323 }
1324
1325 static void clear_probe_trace_event(struct probe_trace_event *tev)
1326 {
1327         struct probe_trace_arg_ref *ref, *next;
1328         int i;
1329
1330         if (tev->event)
1331                 free(tev->event);
1332         if (tev->group)
1333                 free(tev->group);
1334         if (tev->point.symbol)
1335                 free(tev->point.symbol);
1336         for (i = 0; i < tev->nargs; i++) {
1337                 if (tev->args[i].name)
1338                         free(tev->args[i].name);
1339                 if (tev->args[i].value)
1340                         free(tev->args[i].value);
1341                 if (tev->args[i].type)
1342                         free(tev->args[i].type);
1343                 ref = tev->args[i].ref;
1344                 while (ref) {
1345                         next = ref->next;
1346                         free(ref);
1347                         ref = next;
1348                 }
1349         }
1350         if (tev->args)
1351                 free(tev->args);
1352         memset(tev, 0, sizeof(*tev));
1353 }
1354
1355 static int open_kprobe_events(bool readwrite)
1356 {
1357         char buf[PATH_MAX];
1358         const char *__debugfs;
1359         int ret;
1360
1361         __debugfs = debugfs_find_mountpoint();
1362         if (__debugfs == NULL) {
1363                 pr_warning("Debugfs is not mounted.\n");
1364                 return -ENOENT;
1365         }
1366
1367         ret = e_snprintf(buf, PATH_MAX, "%stracing/kprobe_events", __debugfs);
1368         if (ret >= 0) {
1369                 pr_debug("Opening %s write=%d\n", buf, readwrite);
1370                 if (readwrite && !probe_event_dry_run)
1371                         ret = open(buf, O_RDWR, O_APPEND);
1372                 else
1373                         ret = open(buf, O_RDONLY, 0);
1374         }
1375
1376         if (ret < 0) {
1377                 if (errno == ENOENT)
1378                         pr_warning("kprobe_events file does not exist - please"
1379                                  " rebuild kernel with CONFIG_KPROBE_EVENT.\n");
1380                 else
1381                         pr_warning("Failed to open kprobe_events file: %s\n",
1382                                    strerror(errno));
1383         }
1384         return ret;
1385 }
1386
1387 /* Get raw string list of current kprobe_events */
1388 static struct strlist *get_probe_trace_command_rawlist(int fd)
1389 {
1390         int ret, idx;
1391         FILE *fp;
1392         char buf[MAX_CMDLEN];
1393         char *p;
1394         struct strlist *sl;
1395
1396         sl = strlist__new(true, NULL);
1397
1398         fp = fdopen(dup(fd), "r");
1399         while (!feof(fp)) {
1400                 p = fgets(buf, MAX_CMDLEN, fp);
1401                 if (!p)
1402                         break;
1403
1404                 idx = strlen(p) - 1;
1405                 if (p[idx] == '\n')
1406                         p[idx] = '\0';
1407                 ret = strlist__add(sl, buf);
1408                 if (ret < 0) {
1409                         pr_debug("strlist__add failed: %s\n", strerror(-ret));
1410                         strlist__delete(sl);
1411                         return NULL;
1412                 }
1413         }
1414         fclose(fp);
1415
1416         return sl;
1417 }
1418
1419 /* Show an event */
1420 static int show_perf_probe_event(struct perf_probe_event *pev)
1421 {
1422         int i, ret;
1423         char buf[128];
1424         char *place;
1425
1426         /* Synthesize only event probe point */
1427         place = synthesize_perf_probe_point(&pev->point);
1428         if (!place)
1429                 return -EINVAL;
1430
1431         ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event);
1432         if (ret < 0)
1433                 return ret;
1434
1435         printf("  %-20s (on %s", buf, place);
1436
1437         if (pev->nargs > 0) {
1438                 printf(" with");
1439                 for (i = 0; i < pev->nargs; i++) {
1440                         ret = synthesize_perf_probe_arg(&pev->args[i],
1441                                                         buf, 128);
1442                         if (ret < 0)
1443                                 break;
1444                         printf(" %s", buf);
1445                 }
1446         }
1447         printf(")\n");
1448         free(place);
1449         return ret;
1450 }
1451
1452 /* List up current perf-probe events */
1453 int show_perf_probe_events(void)
1454 {
1455         int fd, ret;
1456         struct probe_trace_event tev;
1457         struct perf_probe_event pev;
1458         struct strlist *rawlist;
1459         struct str_node *ent;
1460
1461         setup_pager();
1462         ret = init_vmlinux();
1463         if (ret < 0)
1464                 return ret;
1465
1466         memset(&tev, 0, sizeof(tev));
1467         memset(&pev, 0, sizeof(pev));
1468
1469         fd = open_kprobe_events(false);
1470         if (fd < 0)
1471                 return fd;
1472
1473         rawlist = get_probe_trace_command_rawlist(fd);
1474         close(fd);
1475         if (!rawlist)
1476                 return -ENOENT;
1477
1478         strlist__for_each(ent, rawlist) {
1479                 ret = parse_probe_trace_command(ent->s, &tev);
1480                 if (ret >= 0) {
1481                         ret = convert_to_perf_probe_event(&tev, &pev);
1482                         if (ret >= 0)
1483                                 ret = show_perf_probe_event(&pev);
1484                 }
1485                 clear_perf_probe_event(&pev);
1486                 clear_probe_trace_event(&tev);
1487                 if (ret < 0)
1488                         break;
1489         }
1490         strlist__delete(rawlist);
1491
1492         return ret;
1493 }
1494
1495 /* Get current perf-probe event names */
1496 static struct strlist *get_probe_trace_event_names(int fd, bool include_group)
1497 {
1498         char buf[128];
1499         struct strlist *sl, *rawlist;
1500         struct str_node *ent;
1501         struct probe_trace_event tev;
1502         int ret = 0;
1503
1504         memset(&tev, 0, sizeof(tev));
1505         rawlist = get_probe_trace_command_rawlist(fd);
1506         sl = strlist__new(true, NULL);
1507         strlist__for_each(ent, rawlist) {
1508                 ret = parse_probe_trace_command(ent->s, &tev);
1509                 if (ret < 0)
1510                         break;
1511                 if (include_group) {
1512                         ret = e_snprintf(buf, 128, "%s:%s", tev.group,
1513                                         tev.event);
1514                         if (ret >= 0)
1515                                 ret = strlist__add(sl, buf);
1516                 } else
1517                         ret = strlist__add(sl, tev.event);
1518                 clear_probe_trace_event(&tev);
1519                 if (ret < 0)
1520                         break;
1521         }
1522         strlist__delete(rawlist);
1523
1524         if (ret < 0) {
1525                 strlist__delete(sl);
1526                 return NULL;
1527         }
1528         return sl;
1529 }
1530
1531 static int write_probe_trace_event(int fd, struct probe_trace_event *tev)
1532 {
1533         int ret = 0;
1534         char *buf = synthesize_probe_trace_command(tev);
1535
1536         if (!buf) {
1537                 pr_debug("Failed to synthesize probe trace event.\n");
1538                 return -EINVAL;
1539         }
1540
1541         pr_debug("Writing event: %s\n", buf);
1542         if (!probe_event_dry_run) {
1543                 ret = write(fd, buf, strlen(buf));
1544                 if (ret <= 0)
1545                         pr_warning("Failed to write event: %s\n",
1546                                    strerror(errno));
1547         }
1548         free(buf);
1549         return ret;
1550 }
1551
1552 static int get_new_event_name(char *buf, size_t len, const char *base,
1553                               struct strlist *namelist, bool allow_suffix)
1554 {
1555         int i, ret;
1556
1557         /* Try no suffix */
1558         ret = e_snprintf(buf, len, "%s", base);
1559         if (ret < 0) {
1560                 pr_debug("snprintf() failed: %s\n", strerror(-ret));
1561                 return ret;
1562         }
1563         if (!strlist__has_entry(namelist, buf))
1564                 return 0;
1565
1566         if (!allow_suffix) {
1567                 pr_warning("Error: event \"%s\" already exists. "
1568                            "(Use -f to force duplicates.)\n", base);
1569                 return -EEXIST;
1570         }
1571
1572         /* Try to add suffix */
1573         for (i = 1; i < MAX_EVENT_INDEX; i++) {
1574                 ret = e_snprintf(buf, len, "%s_%d", base, i);
1575                 if (ret < 0) {
1576                         pr_debug("snprintf() failed: %s\n", strerror(-ret));
1577                         return ret;
1578                 }
1579                 if (!strlist__has_entry(namelist, buf))
1580                         break;
1581         }
1582         if (i == MAX_EVENT_INDEX) {
1583                 pr_warning("Too many events are on the same function.\n");
1584                 ret = -ERANGE;
1585         }
1586
1587         return ret;
1588 }
1589
1590 static int __add_probe_trace_events(struct perf_probe_event *pev,
1591                                      struct probe_trace_event *tevs,
1592                                      int ntevs, bool allow_suffix)
1593 {
1594         int i, fd, ret;
1595         struct probe_trace_event *tev = NULL;
1596         char buf[64];
1597         const char *event, *group;
1598         struct strlist *namelist;
1599
1600         fd = open_kprobe_events(true);
1601         if (fd < 0)
1602                 return fd;
1603         /* Get current event names */
1604         namelist = get_probe_trace_event_names(fd, false);
1605         if (!namelist) {
1606                 pr_debug("Failed to get current event list.\n");
1607                 return -EIO;
1608         }
1609
1610         ret = 0;
1611         printf("Add new event%s\n", (ntevs > 1) ? "s:" : ":");
1612         for (i = 0; i < ntevs; i++) {
1613                 tev = &tevs[i];
1614                 if (pev->event)
1615                         event = pev->event;
1616                 else
1617                         if (pev->point.function)
1618                                 event = pev->point.function;
1619                         else
1620                                 event = tev->point.symbol;
1621                 if (pev->group)
1622                         group = pev->group;
1623                 else
1624                         group = PERFPROBE_GROUP;
1625
1626                 /* Get an unused new event name */
1627                 ret = get_new_event_name(buf, 64, event,
1628                                          namelist, allow_suffix);
1629                 if (ret < 0)
1630                         break;
1631                 event = buf;
1632
1633                 tev->event = strdup(event);
1634                 tev->group = strdup(group);
1635                 if (tev->event == NULL || tev->group == NULL) {
1636                         ret = -ENOMEM;
1637                         break;
1638                 }
1639                 ret = write_probe_trace_event(fd, tev);
1640                 if (ret < 0)
1641                         break;
1642                 /* Add added event name to namelist */
1643                 strlist__add(namelist, event);
1644
1645                 /* Trick here - save current event/group */
1646                 event = pev->event;
1647                 group = pev->group;
1648                 pev->event = tev->event;
1649                 pev->group = tev->group;
1650                 show_perf_probe_event(pev);
1651                 /* Trick here - restore current event/group */
1652                 pev->event = (char *)event;
1653                 pev->group = (char *)group;
1654
1655                 /*
1656                  * Probes after the first probe which comes from same
1657                  * user input are always allowed to add suffix, because
1658                  * there might be several addresses corresponding to
1659                  * one code line.
1660                  */
1661                 allow_suffix = true;
1662         }
1663
1664         if (ret >= 0) {
1665                 /* Show how to use the event. */
1666                 printf("\nYou can now use it on all perf tools, such as:\n\n");
1667                 printf("\tperf record -e %s:%s -aR sleep 1\n\n", tev->group,
1668                          tev->event);
1669         }
1670
1671         strlist__delete(namelist);
1672         close(fd);
1673         return ret;
1674 }
1675
1676 static int convert_to_probe_trace_events(struct perf_probe_event *pev,
1677                                           struct probe_trace_event **tevs,
1678                                           int max_tevs, const char *module)
1679 {
1680         struct symbol *sym;
1681         int ret = 0, i;
1682         struct probe_trace_event *tev;
1683
1684         /* Convert perf_probe_event with debuginfo */
1685         ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, module);
1686         if (ret != 0)
1687                 return ret;
1688
1689         /* Allocate trace event buffer */
1690         tev = *tevs = zalloc(sizeof(struct probe_trace_event));
1691         if (tev == NULL)
1692                 return -ENOMEM;
1693
1694         /* Copy parameters */
1695         tev->point.symbol = strdup(pev->point.function);
1696         if (tev->point.symbol == NULL) {
1697                 ret = -ENOMEM;
1698                 goto error;
1699         }
1700         tev->point.offset = pev->point.offset;
1701         tev->point.retprobe = pev->point.retprobe;
1702         tev->nargs = pev->nargs;
1703         if (tev->nargs) {
1704                 tev->args = zalloc(sizeof(struct probe_trace_arg)
1705                                    * tev->nargs);
1706                 if (tev->args == NULL) {
1707                         ret = -ENOMEM;
1708                         goto error;
1709                 }
1710                 for (i = 0; i < tev->nargs; i++) {
1711                         if (pev->args[i].name) {
1712                                 tev->args[i].name = strdup(pev->args[i].name);
1713                                 if (tev->args[i].name == NULL) {
1714                                         ret = -ENOMEM;
1715                                         goto error;
1716                                 }
1717                         }
1718                         tev->args[i].value = strdup(pev->args[i].var);
1719                         if (tev->args[i].value == NULL) {
1720                                 ret = -ENOMEM;
1721                                 goto error;
1722                         }
1723                         if (pev->args[i].type) {
1724                                 tev->args[i].type = strdup(pev->args[i].type);
1725                                 if (tev->args[i].type == NULL) {
1726                                         ret = -ENOMEM;
1727                                         goto error;
1728                                 }
1729                         }
1730                 }
1731         }
1732
1733         /* Currently just checking function name from symbol map */
1734         sym = __find_kernel_function_by_name(tev->point.symbol, NULL);
1735         if (!sym) {
1736                 pr_warning("Kernel symbol \'%s\' not found.\n",
1737                            tev->point.symbol);
1738                 ret = -ENOENT;
1739                 goto error;
1740         }
1741
1742         return 1;
1743 error:
1744         clear_probe_trace_event(tev);
1745         free(tev);
1746         *tevs = NULL;
1747         return ret;
1748 }
1749
1750 struct __event_package {
1751         struct perf_probe_event         *pev;
1752         struct probe_trace_event        *tevs;
1753         int                             ntevs;
1754 };
1755
1756 int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
1757                           int max_tevs, const char *module, bool force_add)
1758 {
1759         int i, j, ret;
1760         struct __event_package *pkgs;
1761
1762         pkgs = zalloc(sizeof(struct __event_package) * npevs);
1763         if (pkgs == NULL)
1764                 return -ENOMEM;
1765
1766         /* Init vmlinux path */
1767         ret = init_vmlinux();
1768         if (ret < 0) {
1769                 free(pkgs);
1770                 return ret;
1771         }
1772
1773         /* Loop 1: convert all events */
1774         for (i = 0; i < npevs; i++) {
1775                 pkgs[i].pev = &pevs[i];
1776                 /* Convert with or without debuginfo */
1777                 ret  = convert_to_probe_trace_events(pkgs[i].pev,
1778                                                      &pkgs[i].tevs,
1779                                                      max_tevs,
1780                                                      module);
1781                 if (ret < 0)
1782                         goto end;
1783                 pkgs[i].ntevs = ret;
1784         }
1785
1786         /* Loop 2: add all events */
1787         for (i = 0; i < npevs && ret >= 0; i++)
1788                 ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs,
1789                                                 pkgs[i].ntevs, force_add);
1790 end:
1791         /* Loop 3: cleanup and free trace events  */
1792         for (i = 0; i < npevs; i++) {
1793                 for (j = 0; j < pkgs[i].ntevs; j++)
1794                         clear_probe_trace_event(&pkgs[i].tevs[j]);
1795                 free(pkgs[i].tevs);
1796         }
1797         free(pkgs);
1798
1799         return ret;
1800 }
1801
1802 static int __del_trace_probe_event(int fd, struct str_node *ent)
1803 {
1804         char *p;
1805         char buf[128];
1806         int ret;
1807
1808         /* Convert from perf-probe event to trace-probe event */
1809         ret = e_snprintf(buf, 128, "-:%s", ent->s);
1810         if (ret < 0)
1811                 goto error;
1812
1813         p = strchr(buf + 2, ':');
1814         if (!p) {
1815                 pr_debug("Internal error: %s should have ':' but not.\n",
1816                          ent->s);
1817                 ret = -ENOTSUP;
1818                 goto error;
1819         }
1820         *p = '/';
1821
1822         pr_debug("Writing event: %s\n", buf);
1823         ret = write(fd, buf, strlen(buf));
1824         if (ret < 0)
1825                 goto error;
1826
1827         printf("Remove event: %s\n", ent->s);
1828         return 0;
1829 error:
1830         pr_warning("Failed to delete event: %s\n", strerror(-ret));
1831         return ret;
1832 }
1833
1834 static int del_trace_probe_event(int fd, const char *group,
1835                                   const char *event, struct strlist *namelist)
1836 {
1837         char buf[128];
1838         struct str_node *ent, *n;
1839         int found = 0, ret = 0;
1840
1841         ret = e_snprintf(buf, 128, "%s:%s", group, event);
1842         if (ret < 0) {
1843                 pr_err("Failed to copy event.\n");
1844                 return ret;
1845         }
1846
1847         if (strpbrk(buf, "*?")) { /* Glob-exp */
1848                 strlist__for_each_safe(ent, n, namelist)
1849                         if (strglobmatch(ent->s, buf)) {
1850                                 found++;
1851                                 ret = __del_trace_probe_event(fd, ent);
1852                                 if (ret < 0)
1853                                         break;
1854                                 strlist__remove(namelist, ent);
1855                         }
1856         } else {
1857                 ent = strlist__find(namelist, buf);
1858                 if (ent) {
1859                         found++;
1860                         ret = __del_trace_probe_event(fd, ent);
1861                         if (ret >= 0)
1862                                 strlist__remove(namelist, ent);
1863                 }
1864         }
1865         if (found == 0 && ret >= 0)
1866                 pr_info("Info: Event \"%s\" does not exist.\n", buf);
1867
1868         return ret;
1869 }
1870
1871 int del_perf_probe_events(struct strlist *dellist)
1872 {
1873         int fd, ret = 0;
1874         const char *group, *event;
1875         char *p, *str;
1876         struct str_node *ent;
1877         struct strlist *namelist;
1878
1879         fd = open_kprobe_events(true);
1880         if (fd < 0)
1881                 return fd;
1882
1883         /* Get current event names */
1884         namelist = get_probe_trace_event_names(fd, true);
1885         if (namelist == NULL)
1886                 return -EINVAL;
1887
1888         strlist__for_each(ent, dellist) {
1889                 str = strdup(ent->s);
1890                 if (str == NULL) {
1891                         ret = -ENOMEM;
1892                         break;
1893                 }
1894                 pr_debug("Parsing: %s\n", str);
1895                 p = strchr(str, ':');
1896                 if (p) {
1897                         group = str;
1898                         *p = '\0';
1899                         event = p + 1;
1900                 } else {
1901                         group = "*";
1902                         event = str;
1903                 }
1904                 pr_debug("Group: %s, Event: %s\n", group, event);
1905                 ret = del_trace_probe_event(fd, group, event, namelist);
1906                 free(str);
1907                 if (ret < 0)
1908                         break;
1909         }
1910         strlist__delete(namelist);
1911         close(fd);
1912
1913         return ret;
1914 }
1915