1// SPDX-License-Identifier: GPL-2.0 2#include <internal/lib.h> 3#include <subcmd/parse-options.h> 4#include <api/fd/array.h> 5#include <api/fs/fs.h> 6#include <linux/zalloc.h> 7#include <linux/string.h> 8#include <linux/limits.h> 9#include <string.h> 10#include <sys/file.h> 11#include <signal.h> 12#include <stdlib.h> 13#include <time.h> 14#include <stdio.h> 15#include <unistd.h> 16#include <errno.h> 17#include <sys/inotify.h> 18#include <libgen.h> 19#include <sys/types.h> 20#include <sys/socket.h> 21#include <sys/un.h> 22#include <sys/stat.h> 23#include <sys/signalfd.h> 24#include <sys/wait.h> 25#include <poll.h> 26#include "builtin.h" 27#include "perf.h" 28#include "debug.h" 29#include "config.h" 30#include "util.h" 31 32#define SESSION_OUTPUT "output" 33#define SESSION_CONTROL "control" 34#define SESSION_ACK "ack" 35 36/* 37 * Session states: 38 * 39 * OK - session is up and running 40 * RECONFIG - session is pending for reconfiguration, 41 * new values are already loaded in session object 42 * KILL - session is pending to be killed 43 * 44 * Session object life and its state is maintained by 45 * following functions: 46 * 47 * setup_server_config 48 * - reads config file and setup session objects 49 * with following states: 50 * 51 * OK - no change needed 52 * RECONFIG - session needs to be changed 53 * (run variable changed) 54 * KILL - session needs to be killed 55 * (session is no longer in config file) 56 * 57 * daemon__reconfig 58 * - scans session objects and does following actions 59 * for states: 60 * 61 * OK - skip 62 * RECONFIG - session is killed and re-run with new config 63 * KILL - session is killed 64 * 65 * - all sessions have OK state on the function exit 66 */ 67enum daemon_session_state { 68 OK, 69 RECONFIG, 70 KILL, 71}; 72 73struct daemon_session { 74 char *base; 75 char *name; 76 char *run; 77 char *control; 78 int pid; 79 struct list_head list; 80 enum daemon_session_state state; 81 time_t start; 82}; 83 84struct daemon { 85 const char *config; 86 char *config_real; 87 char *config_base; 88 const char *csv_sep; 89 const char *base_user; 90 char *base; 91 struct list_head sessions; 92 FILE *out; 93 char *perf; 94 int signal_fd; 95 time_t start; 96}; 97 98static struct daemon __daemon = { 99 .sessions = LIST_HEAD_INIT(__daemon.sessions), 100}; 101 102static const char * const daemon_usage[] = { 103 "perf daemon {start|signal|stop|ping} [<options>]", 104 "perf daemon [<options>]", 105 NULL 106}; 107 108static volatile sig_atomic_t done; 109 110static void sig_handler(int sig __maybe_unused) 111{ 112 done = true; 113} 114 115static struct daemon_session *daemon__add_session(struct daemon *config, char *name) 116{ 117 struct daemon_session *session = zalloc(sizeof(*session)); 118 119 if (!session) 120 return NULL; 121 122 session->name = strdup(name); 123 if (!session->name) { 124 free(session); 125 return NULL; 126 } 127 128 session->pid = -1; 129 list_add_tail(&session->list, &config->sessions); 130 return session; 131} 132 133static struct daemon_session *daemon__find_session(struct daemon *daemon, char *name) 134{ 135 struct daemon_session *session; 136 137 list_for_each_entry(session, &daemon->sessions, list) { 138 if (!strcmp(session->name, name)) 139 return session; 140 } 141 142 return NULL; 143} 144 145static int get_session_name(const char *var, char *session, int len) 146{ 147 const char *p = var + sizeof("session-") - 1; 148 149 while (*p != '.' && *p != 0x0 && len--) 150 *session++ = *p++; 151 152 *session = 0; 153 return *p == '.' ? 0 : -EINVAL; 154} 155 156static int session_config(struct daemon *daemon, const char *var, const char *value) 157{ 158 struct daemon_session *session; 159 char name[100]; 160 161 if (get_session_name(var, name, sizeof(name) - 1)) 162 return -EINVAL; 163 164 var = strchr(var, '.'); 165 if (!var) 166 return -EINVAL; 167 168 var++; 169 170 session = daemon__find_session(daemon, name); 171 172 if (!session) { 173 /* New session is defined. */ 174 session = daemon__add_session(daemon, name); 175 if (!session) 176 return -ENOMEM; 177 178 pr_debug("reconfig: found new session %s\n", name); 179 180 /* Trigger reconfig to start it. */ 181 session->state = RECONFIG; 182 } else if (session->state == KILL) { 183 /* Current session is defined, no action needed. */ 184 pr_debug("reconfig: found current session %s\n", name); 185 session->state = OK; 186 } 187 188 if (!strcmp(var, "run")) { 189 bool same = false; 190 191 if (session->run) 192 same = !strcmp(session->run, value); 193 194 if (!same) { 195 if (session->run) { 196 zfree(&session->run); 197 pr_debug("reconfig: session %s is changed\n", name); 198 } 199 200 session->run = strdup(value); 201 if (!session->run) 202 return -ENOMEM; 203 204 /* 205 * Either new or changed run value is defined, 206 * trigger reconfig for the session. 207 */ 208 session->state = RECONFIG; 209 } 210 } 211 212 return 0; 213} 214 215static int server_config(const char *var, const char *value, void *cb) 216{ 217 struct daemon *daemon = cb; 218 219 if (strstarts(var, "session-")) { 220 return session_config(daemon, var, value); 221 } else if (!strcmp(var, "daemon.base") && !daemon->base_user) { 222 if (daemon->base && strcmp(daemon->base, value)) { 223 pr_err("failed: can't redefine base, bailing out\n"); 224 return -EINVAL; 225 } 226 daemon->base = strdup(value); 227 if (!daemon->base) 228 return -ENOMEM; 229 } 230 231 return 0; 232} 233 234static int client_config(const char *var, const char *value, void *cb) 235{ 236 struct daemon *daemon = cb; 237 238 if (!strcmp(var, "daemon.base") && !daemon->base_user) { 239 daemon->base = strdup(value); 240 if (!daemon->base) 241 return -ENOMEM; 242 } 243 244 return 0; 245} 246 247static int check_base(struct daemon *daemon) 248{ 249 struct stat st; 250 251 if (!daemon->base) { 252 pr_err("failed: base not defined\n"); 253 return -EINVAL; 254 } 255 256 if (stat(daemon->base, &st)) { 257 switch (errno) { 258 case EACCES: 259 pr_err("failed: permission denied for '%s' base\n", 260 daemon->base); 261 return -EACCES; 262 case ENOENT: 263 pr_err("failed: base '%s' does not exists\n", 264 daemon->base); 265 return -EACCES; 266 default: 267 pr_err("failed: can't access base '%s': %s\n", 268 daemon->base, strerror(errno)); 269 return -errno; 270 } 271 } 272 273 if ((st.st_mode & S_IFMT) != S_IFDIR) { 274 pr_err("failed: base '%s' is not directory\n", 275 daemon->base); 276 return -EINVAL; 277 } 278 279 return 0; 280} 281 282static int setup_client_config(struct daemon *daemon) 283{ 284 struct perf_config_set *set = perf_config_set__load_file(daemon->config_real); 285 int err = -ENOMEM; 286 287 if (set) { 288 err = perf_config_set(set, client_config, daemon); 289 perf_config_set__delete(set); 290 } 291 292 return err ?: check_base(daemon); 293} 294 295static int setup_server_config(struct daemon *daemon) 296{ 297 struct perf_config_set *set; 298 struct daemon_session *session; 299 int err = -ENOMEM; 300 301 pr_debug("reconfig: started\n"); 302 303 /* 304 * Mark all sessions for kill, the server config 305 * will set following states, see explanation at 306 * enum daemon_session_state declaration. 307 */ 308 list_for_each_entry(session, &daemon->sessions, list) 309 session->state = KILL; 310 311 set = perf_config_set__load_file(daemon->config_real); 312 if (set) { 313 err = perf_config_set(set, server_config, daemon); 314 perf_config_set__delete(set); 315 } 316 317 return err ?: check_base(daemon); 318} 319 320static int daemon_session__run(struct daemon_session *session, 321 struct daemon *daemon) 322{ 323 char buf[PATH_MAX]; 324 char **argv; 325 int argc, fd; 326 327 if (asprintf(&session->base, "%s/session-%s", 328 daemon->base, session->name) < 0) { 329 perror("failed: asprintf"); 330 return -1; 331 } 332 333 if (mkdir(session->base, 0755) && errno != EEXIST) { 334 perror("failed: mkdir"); 335 return -1; 336 } 337 338 session->start = time(NULL); 339 340 session->pid = fork(); 341 if (session->pid < 0) 342 return -1; 343 if (session->pid > 0) { 344 pr_info("reconfig: ruining session [%s:%d]: %s\n", 345 session->name, session->pid, session->run); 346 return 0; 347 } 348 349 if (chdir(session->base)) { 350 perror("failed: chdir"); 351 return -1; 352 } 353 354 fd = open("/dev/null", O_RDONLY); 355 if (fd < 0) { 356 perror("failed: open /dev/null"); 357 return -1; 358 } 359 360 dup2(fd, 0); 361 close(fd); 362 363 fd = open(SESSION_OUTPUT, O_RDWR|O_CREAT|O_TRUNC, 0644); 364 if (fd < 0) { 365 perror("failed: open session output"); 366 return -1; 367 } 368 369 dup2(fd, 1); 370 dup2(fd, 2); 371 close(fd); 372 373 if (mkfifo(SESSION_CONTROL, 0600) && errno != EEXIST) { 374 perror("failed: create control fifo"); 375 return -1; 376 } 377 378 if (mkfifo(SESSION_ACK, 0600) && errno != EEXIST) { 379 perror("failed: create ack fifo"); 380 return -1; 381 } 382 383 scnprintf(buf, sizeof(buf), "%s record --control=fifo:%s,%s %s", 384 daemon->perf, SESSION_CONTROL, SESSION_ACK, session->run); 385 386 argv = argv_split(buf, &argc); 387 if (!argv) 388 exit(-1); 389 390 exit(execve(daemon->perf, argv, NULL)); 391 return -1; 392} 393 394static pid_t handle_signalfd(struct daemon *daemon) 395{ 396 struct daemon_session *session; 397 struct signalfd_siginfo si; 398 ssize_t err; 399 int status; 400 pid_t pid; 401 402 /* 403 * Take signal fd data as pure signal notification and check all 404 * the sessions state. The reason is that multiple signals can get 405 * coalesced in kernel and we can receive only single signal even 406 * if multiple SIGCHLD were generated. 407 */ 408 err = read(daemon->signal_fd, &si, sizeof(struct signalfd_siginfo)); 409 if (err != sizeof(struct signalfd_siginfo)) { 410 pr_err("failed to read signal fd\n"); 411 return -1; 412 } 413 414 list_for_each_entry(session, &daemon->sessions, list) { 415 if (session->pid == -1) 416 continue; 417 418 pid = waitpid(session->pid, &status, WNOHANG); 419 if (pid <= 0) 420 continue; 421 422 if (WIFEXITED(status)) { 423 pr_info("session '%s' exited, status=%d\n", 424 session->name, WEXITSTATUS(status)); 425 } else if (WIFSIGNALED(status)) { 426 pr_info("session '%s' killed (signal %d)\n", 427 session->name, WTERMSIG(status)); 428 } else if (WIFSTOPPED(status)) { 429 pr_info("session '%s' stopped (signal %d)\n", 430 session->name, WSTOPSIG(status)); 431 } else { 432 pr_info("session '%s' Unexpected status (0x%x)\n", 433 session->name, status); 434 } 435 436 session->state = KILL; 437 session->pid = -1; 438 } 439 440 return 0; 441} 442 443static int daemon_session__wait(struct daemon_session *session, struct daemon *daemon, 444 int secs) 445{ 446 struct pollfd pollfd = { 447 .fd = daemon->signal_fd, 448 .events = POLLIN, 449 }; 450 time_t start; 451 452 start = time(NULL); 453 454 do { 455 int err = poll(&pollfd, 1, 1000); 456 457 if (err > 0) { 458 handle_signalfd(daemon); 459 } else if (err < 0) { 460 perror("failed: poll\n"); 461 return -1; 462 } 463 464 if (start + secs < time(NULL)) 465 return -1; 466 } while (session->pid != -1); 467 468 return 0; 469} 470 471static bool daemon__has_alive_session(struct daemon *daemon) 472{ 473 struct daemon_session *session; 474 475 list_for_each_entry(session, &daemon->sessions, list) { 476 if (session->pid != -1) 477 return true; 478 } 479 480 return false; 481} 482 483static int daemon__wait(struct daemon *daemon, int secs) 484{ 485 struct pollfd pollfd = { 486 .fd = daemon->signal_fd, 487 .events = POLLIN, 488 }; 489 time_t start; 490 491 start = time(NULL); 492 493 do { 494 int err = poll(&pollfd, 1, 1000); 495 496 if (err > 0) { 497 handle_signalfd(daemon); 498 } else if (err < 0) { 499 perror("failed: poll\n"); 500 return -1; 501 } 502 503 if (start + secs < time(NULL)) 504 return -1; 505 } while (daemon__has_alive_session(daemon)); 506 507 return 0; 508} 509 510static int daemon_session__control(struct daemon_session *session, 511 const char *msg, bool do_ack) 512{ 513 struct pollfd pollfd = { .events = POLLIN, }; 514 char control_path[PATH_MAX]; 515 char ack_path[PATH_MAX]; 516 int control, ack = -1, len; 517 char buf[20]; 518 int ret = -1; 519 ssize_t err; 520 521 /* open the control file */ 522 scnprintf(control_path, sizeof(control_path), "%s/%s", 523 session->base, SESSION_CONTROL); 524 525 control = open(control_path, O_WRONLY|O_NONBLOCK); 526 if (!control) 527 return -1; 528 529 if (do_ack) { 530 /* open the ack file */ 531 scnprintf(ack_path, sizeof(ack_path), "%s/%s", 532 session->base, SESSION_ACK); 533 534 ack = open(ack_path, O_RDONLY, O_NONBLOCK); 535 if (!ack) { 536 close(control); 537 return -1; 538 } 539 } 540 541 /* write the command */ 542 len = strlen(msg); 543 544 err = writen(control, msg, len); 545 if (err != len) { 546 pr_err("failed: write to control pipe: %d (%s)\n", 547 errno, control_path); 548 goto out; 549 } 550 551 if (!do_ack) 552 goto out; 553 554 /* wait for an ack */ 555 pollfd.fd = ack; 556 557 if (!poll(&pollfd, 1, 2000)) { 558 pr_err("failed: control ack timeout\n"); 559 goto out; 560 } 561 562 if (!(pollfd.revents & POLLIN)) { 563 pr_err("failed: did not received an ack\n"); 564 goto out; 565 } 566 567 err = read(ack, buf, sizeof(buf)); 568 if (err > 0) 569 ret = strcmp(buf, "ack\n"); 570 else 571 perror("failed: read ack %d\n"); 572 573out: 574 if (ack != -1) 575 close(ack); 576 577 close(control); 578 return ret; 579} 580 581static int setup_server_socket(struct daemon *daemon) 582{ 583 struct sockaddr_un addr; 584 char path[PATH_MAX]; 585 int fd = socket(AF_UNIX, SOCK_STREAM, 0); 586 587 if (fd < 0) { 588 fprintf(stderr, "socket: %s\n", strerror(errno)); 589 return -1; 590 } 591 592 if (fcntl(fd, F_SETFD, FD_CLOEXEC)) { 593 perror("failed: fcntl FD_CLOEXEC"); 594 close(fd); 595 return -1; 596 } 597 598 scnprintf(path, sizeof(path), "%s/control", daemon->base); 599 600 if (strlen(path) + 1 >= sizeof(addr.sun_path)) { 601 pr_err("failed: control path too long '%s'\n", path); 602 close(fd); 603 return -1; 604 } 605 606 memset(&addr, 0, sizeof(addr)); 607 addr.sun_family = AF_UNIX; 608 609 strlcpy(addr.sun_path, path, sizeof(addr.sun_path) - 1); 610 unlink(path); 611 612 if (bind(fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) { 613 perror("failed: bind"); 614 close(fd); 615 return -1; 616 } 617 618 if (listen(fd, 1) == -1) { 619 perror("failed: listen"); 620 close(fd); 621 return -1; 622 } 623 624 return fd; 625} 626 627enum { 628 CMD_LIST = 0, 629 CMD_SIGNAL = 1, 630 CMD_STOP = 2, 631 CMD_PING = 3, 632 CMD_MAX, 633}; 634 635#define SESSION_MAX 64 636 637union cmd { 638 int cmd; 639 640 /* CMD_LIST */ 641 struct { 642 int cmd; 643 int verbose; 644 char csv_sep; 645 } list; 646 647 /* CMD_SIGNAL */ 648 struct { 649 int cmd; 650 int sig; 651 char name[SESSION_MAX]; 652 } signal; 653 654 /* CMD_PING */ 655 struct { 656 int cmd; 657 char name[SESSION_MAX]; 658 } ping; 659}; 660 661enum { 662 PING_OK = 0, 663 PING_FAIL = 1, 664 PING_MAX, 665}; 666 667static int daemon_session__ping(struct daemon_session *session) 668{ 669 return daemon_session__control(session, "ping", true) ? PING_FAIL : PING_OK; 670} 671 672static int cmd_session_list(struct daemon *daemon, union cmd *cmd, FILE *out) 673{ 674 char csv_sep = cmd->list.csv_sep; 675 struct daemon_session *session; 676 time_t curr = time(NULL); 677 678 if (csv_sep) { 679 fprintf(out, "%d%c%s%c%s%c%s/%s", 680 /* pid daemon */ 681 getpid(), csv_sep, "daemon", 682 /* base */ 683 csv_sep, daemon->base, 684 /* output */ 685 csv_sep, daemon->base, SESSION_OUTPUT); 686 687 fprintf(out, "%c%s/%s", 688 /* lock */ 689 csv_sep, daemon->base, "lock"); 690 691 fprintf(out, "%c%lu", 692 /* session up time */ 693 csv_sep, (curr - daemon->start) / 60); 694 695 fprintf(out, "\n"); 696 } else { 697 fprintf(out, "[%d:daemon] base: %s\n", getpid(), daemon->base); 698 if (cmd->list.verbose) { 699 fprintf(out, " output: %s/%s\n", 700 daemon->base, SESSION_OUTPUT); 701 fprintf(out, " lock: %s/lock\n", 702 daemon->base); 703 fprintf(out, " up: %lu minutes\n", 704 (curr - daemon->start) / 60); 705 } 706 } 707 708 list_for_each_entry(session, &daemon->sessions, list) { 709 if (csv_sep) { 710 fprintf(out, "%d%c%s%c%s", 711 /* pid */ 712 session->pid, 713 /* name */ 714 csv_sep, session->name, 715 /* base */ 716 csv_sep, session->run); 717 718 fprintf(out, "%c%s%c%s/%s", 719 /* session dir */ 720 csv_sep, session->base, 721 /* session output */ 722 csv_sep, session->base, SESSION_OUTPUT); 723 724 fprintf(out, "%c%s/%s%c%s/%s", 725 /* session control */ 726 csv_sep, session->base, SESSION_CONTROL, 727 /* session ack */ 728 csv_sep, session->base, SESSION_ACK); 729 730 fprintf(out, "%c%lu", 731 /* session up time */ 732 csv_sep, (curr - session->start) / 60); 733 734 fprintf(out, "\n"); 735 } else { 736 fprintf(out, "[%d:%s] perf record %s\n", 737 session->pid, session->name, session->run); 738 if (!cmd->list.verbose) 739 continue; 740 fprintf(out, " base: %s\n", 741 session->base); 742 fprintf(out, " output: %s/%s\n", 743 session->base, SESSION_OUTPUT); 744 fprintf(out, " control: %s/%s\n", 745 session->base, SESSION_CONTROL); 746 fprintf(out, " ack: %s/%s\n", 747 session->base, SESSION_ACK); 748 fprintf(out, " up: %lu minutes\n", 749 (curr - session->start) / 60); 750 } 751 } 752 753 return 0; 754} 755 756static int daemon_session__signal(struct daemon_session *session, int sig) 757{ 758 if (session->pid < 0) 759 return -1; 760 return kill(session->pid, sig); 761} 762 763static int cmd_session_kill(struct daemon *daemon, union cmd *cmd, FILE *out) 764{ 765 struct daemon_session *session; 766 bool all = false; 767 768 all = !strcmp(cmd->signal.name, "all"); 769 770 list_for_each_entry(session, &daemon->sessions, list) { 771 if (all || !strcmp(cmd->signal.name, session->name)) { 772 daemon_session__signal(session, cmd->signal.sig); 773 fprintf(out, "signal %d sent to session '%s [%d]'\n", 774 cmd->signal.sig, session->name, session->pid); 775 } 776 } 777 778 return 0; 779} 780 781static const char *ping_str[PING_MAX] = { 782 [PING_OK] = "OK", 783 [PING_FAIL] = "FAIL", 784}; 785 786static int cmd_session_ping(struct daemon *daemon, union cmd *cmd, FILE *out) 787{ 788 struct daemon_session *session; 789 bool all = false, found = false; 790 791 all = !strcmp(cmd->ping.name, "all"); 792 793 list_for_each_entry(session, &daemon->sessions, list) { 794 if (all || !strcmp(cmd->ping.name, session->name)) { 795 int state = daemon_session__ping(session); 796 797 fprintf(out, "%-4s %s\n", ping_str[state], session->name); 798 found = true; 799 } 800 } 801 802 if (!found && !all) { 803 fprintf(out, "%-4s %s (not found)\n", 804 ping_str[PING_FAIL], cmd->ping.name); 805 } 806 return 0; 807} 808 809static int handle_server_socket(struct daemon *daemon, int sock_fd) 810{ 811 int ret = -1, fd; 812 FILE *out = NULL; 813 union cmd cmd; 814 815 fd = accept(sock_fd, NULL, NULL); 816 if (fd < 0) { 817 perror("failed: accept"); 818 return -1; 819 } 820 821 if (sizeof(cmd) != readn(fd, &cmd, sizeof(cmd))) { 822 perror("failed: read"); 823 goto out; 824 } 825 826 out = fdopen(fd, "w"); 827 if (!out) { 828 perror("failed: fdopen"); 829 goto out; 830 } 831 832 switch (cmd.cmd) { 833 case CMD_LIST: 834 ret = cmd_session_list(daemon, &cmd, out); 835 break; 836 case CMD_SIGNAL: 837 ret = cmd_session_kill(daemon, &cmd, out); 838 break; 839 case CMD_STOP: 840 done = 1; 841 ret = 0; 842 pr_debug("perf daemon is exciting\n"); 843 break; 844 case CMD_PING: 845 ret = cmd_session_ping(daemon, &cmd, out); 846 break; 847 default: 848 break; 849 } 850 851 fclose(out); 852out: 853 /* If out is defined, then fd is closed via fclose. */ 854 if (!out) 855 close(fd); 856 return ret; 857} 858 859static int setup_client_socket(struct daemon *daemon) 860{ 861 struct sockaddr_un addr; 862 char path[PATH_MAX]; 863 int fd = socket(AF_UNIX, SOCK_STREAM, 0); 864 865 if (fd == -1) { 866 perror("failed: socket"); 867 return -1; 868 } 869 870 scnprintf(path, sizeof(path), "%s/control", daemon->base); 871 872 if (strlen(path) + 1 >= sizeof(addr.sun_path)) { 873 pr_err("failed: control path too long '%s'\n", path); 874 close(fd); 875 return -1; 876 } 877 878 memset(&addr, 0, sizeof(addr)); 879 addr.sun_family = AF_UNIX; 880 strlcpy(addr.sun_path, path, sizeof(addr.sun_path) - 1); 881 882 if (connect(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1) { 883 perror("failed: connect"); 884 close(fd); 885 return -1; 886 } 887 888 return fd; 889} 890 891static void daemon_session__kill(struct daemon_session *session, 892 struct daemon *daemon) 893{ 894 int how = 0; 895 896 do { 897 switch (how) { 898 case 0: 899 daemon_session__control(session, "stop", false); 900 break; 901 case 1: 902 daemon_session__signal(session, SIGTERM); 903 break; 904 case 2: 905 daemon_session__signal(session, SIGKILL); 906 break; 907 default: 908 pr_err("failed to wait for session %s\n", 909 session->name); 910 return; 911 } 912 how++; 913 914 } while (daemon_session__wait(session, daemon, 10)); 915} 916 917static void daemon__signal(struct daemon *daemon, int sig) 918{ 919 struct daemon_session *session; 920 921 list_for_each_entry(session, &daemon->sessions, list) 922 daemon_session__signal(session, sig); 923} 924 925static void daemon_session__delete(struct daemon_session *session) 926{ 927 zfree(&session->base); 928 zfree(&session->name); 929 zfree(&session->run); 930 free(session); 931} 932 933static void daemon_session__remove(struct daemon_session *session) 934{ 935 list_del(&session->list); 936 daemon_session__delete(session); 937} 938 939static void daemon__stop(struct daemon *daemon) 940{ 941 struct daemon_session *session; 942 943 list_for_each_entry(session, &daemon->sessions, list) 944 daemon_session__control(session, "stop", false); 945} 946 947static void daemon__kill(struct daemon *daemon) 948{ 949 int how = 0; 950 951 do { 952 switch (how) { 953 case 0: 954 daemon__stop(daemon); 955 break; 956 case 1: 957 daemon__signal(daemon, SIGTERM); 958 break; 959 case 2: 960 daemon__signal(daemon, SIGKILL); 961 break; 962 default: 963 pr_err("failed to wait for sessions\n"); 964 return; 965 } 966 how++; 967 968 } while (daemon__wait(daemon, 10)); 969} 970 971static void daemon__exit(struct daemon *daemon) 972{ 973 struct daemon_session *session, *h; 974 975 list_for_each_entry_safe(session, h, &daemon->sessions, list) 976 daemon_session__remove(session); 977 978 zfree(&daemon->config_real); 979 zfree(&daemon->config_base); 980 zfree(&daemon->base); 981} 982 983static int daemon__reconfig(struct daemon *daemon) 984{ 985 struct daemon_session *session, *n; 986 987 list_for_each_entry_safe(session, n, &daemon->sessions, list) { 988 /* No change. */ 989 if (session->state == OK) 990 continue; 991 992 /* Remove session. */ 993 if (session->state == KILL) { 994 if (session->pid > 0) { 995 daemon_session__kill(session, daemon); 996 pr_info("reconfig: session '%s' killed\n", session->name); 997 } 998 daemon_session__remove(session); 999 continue; 1000 } 1001 1002 /* Reconfig session. */ 1003 if (session->pid > 0) { 1004 daemon_session__kill(session, daemon); 1005 pr_info("reconfig: session '%s' killed\n", session->name); 1006 } 1007 if (daemon_session__run(session, daemon)) 1008 return -1; 1009 1010 session->state = OK; 1011 } 1012 1013 return 0; 1014} 1015 1016static int setup_config_changes(struct daemon *daemon) 1017{ 1018 char *basen = strdup(daemon->config_real); 1019 char *dirn = strdup(daemon->config_real); 1020 char *base, *dir; 1021 int fd, wd = -1; 1022 1023 if (!dirn || !basen) 1024 goto out; 1025 1026 fd = inotify_init1(IN_NONBLOCK|O_CLOEXEC); 1027 if (fd < 0) { 1028 perror("failed: inotify_init"); 1029 goto out; 1030 } 1031 1032 dir = dirname(dirn); 1033 base = basename(basen); 1034 pr_debug("config file: %s, dir: %s\n", base, dir); 1035 1036 wd = inotify_add_watch(fd, dir, IN_CLOSE_WRITE); 1037 if (wd >= 0) { 1038 daemon->config_base = strdup(base); 1039 if (!daemon->config_base) { 1040 close(fd); 1041 wd = -1; 1042 } 1043 } else { 1044 perror("failed: inotify_add_watch"); 1045 } 1046 1047out: 1048 free(basen); 1049 free(dirn); 1050 return wd < 0 ? -1 : fd; 1051} 1052 1053static bool process_inotify_event(struct daemon *daemon, char *buf, ssize_t len) 1054{ 1055 char *p = buf; 1056 1057 while (p < (buf + len)) { 1058 struct inotify_event *event = (struct inotify_event *) p; 1059 1060 /* 1061 * We monitor config directory, check if our 1062 * config file was changes. 1063 */ 1064 if ((event->mask & IN_CLOSE_WRITE) && 1065 !(event->mask & IN_ISDIR)) { 1066 if (!strcmp(event->name, daemon->config_base)) 1067 return true; 1068 } 1069 p += sizeof(*event) + event->len; 1070 } 1071 return false; 1072} 1073 1074static int handle_config_changes(struct daemon *daemon, int conf_fd, 1075 bool *config_changed) 1076{ 1077 char buf[4096]; 1078 ssize_t len; 1079 1080 while (!(*config_changed)) { 1081 len = read(conf_fd, buf, sizeof(buf)); 1082 if (len == -1) { 1083 if (errno != EAGAIN) { 1084 perror("failed: read"); 1085 return -1; 1086 } 1087 return 0; 1088 } 1089 *config_changed = process_inotify_event(daemon, buf, len); 1090 } 1091 return 0; 1092} 1093 1094static int setup_config(struct daemon *daemon) 1095{ 1096 if (daemon->base_user) { 1097 daemon->base = strdup(daemon->base_user); 1098 if (!daemon->base) 1099 return -ENOMEM; 1100 } 1101 1102 if (daemon->config) { 1103 char *real = realpath(daemon->config, NULL); 1104 1105 if (!real) { 1106 perror("failed: realpath"); 1107 return -1; 1108 } 1109 daemon->config_real = real; 1110 return 0; 1111 } 1112 1113 if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) 1114 daemon->config_real = strdup(perf_etc_perfconfig()); 1115 else if (perf_config_global() && perf_home_perfconfig()) 1116 daemon->config_real = strdup(perf_home_perfconfig()); 1117 1118 return daemon->config_real ? 0 : -1; 1119} 1120 1121#ifndef F_TLOCK 1122#define F_TLOCK 2 1123 1124static int lockf(int fd, int cmd, off_t len) 1125{ 1126 if (cmd != F_TLOCK || len != 0) 1127 return -1; 1128 1129 return flock(fd, LOCK_EX | LOCK_NB); 1130} 1131#endif // F_TLOCK 1132 1133/* 1134 * Each daemon tries to create and lock BASE/lock file, 1135 * if it's successful we are sure we're the only daemon 1136 * running over the BASE. 1137 * 1138 * Once daemon is finished, file descriptor to lock file 1139 * is closed and lock is released. 1140 */ 1141static int check_lock(struct daemon *daemon) 1142{ 1143 char path[PATH_MAX]; 1144 char buf[20]; 1145 int fd, pid; 1146 ssize_t len; 1147 1148 scnprintf(path, sizeof(path), "%s/lock", daemon->base); 1149 1150 fd = open(path, O_RDWR|O_CREAT|O_CLOEXEC, 0640); 1151 if (fd < 0) 1152 return -1; 1153 1154 if (lockf(fd, F_TLOCK, 0) < 0) { 1155 filename__read_int(path, &pid); 1156 fprintf(stderr, "failed: another perf daemon (pid %d) owns %s\n", 1157 pid, daemon->base); 1158 close(fd); 1159 return -1; 1160 } 1161 1162 scnprintf(buf, sizeof(buf), "%d", getpid()); 1163 len = strlen(buf); 1164 1165 if (write(fd, buf, len) != len) { 1166 perror("failed: write"); 1167 close(fd); 1168 return -1; 1169 } 1170 1171 if (ftruncate(fd, len)) { 1172 perror("failed: ftruncate"); 1173 close(fd); 1174 return -1; 1175 } 1176 1177 return 0; 1178} 1179 1180static int go_background(struct daemon *daemon) 1181{ 1182 int pid, fd; 1183 1184 pid = fork(); 1185 if (pid < 0) 1186 return -1; 1187 1188 if (pid > 0) 1189 return 1; 1190 1191 if (setsid() < 0) 1192 return -1; 1193 1194 if (check_lock(daemon)) 1195 return -1; 1196 1197 umask(0); 1198 1199 if (chdir(daemon->base)) { 1200 perror("failed: chdir"); 1201 return -1; 1202 } 1203 1204 fd = open("output", O_RDWR|O_CREAT|O_TRUNC, 0644); 1205 if (fd < 0) { 1206 perror("failed: open"); 1207 return -1; 1208 } 1209 1210 if (fcntl(fd, F_SETFD, FD_CLOEXEC)) { 1211 perror("failed: fcntl FD_CLOEXEC"); 1212 close(fd); 1213 return -1; 1214 } 1215 1216 close(0); 1217 dup2(fd, 1); 1218 dup2(fd, 2); 1219 close(fd); 1220 1221 daemon->out = fdopen(1, "w"); 1222 if (!daemon->out) { 1223 close(1); 1224 close(2); 1225 return -1; 1226 } 1227 1228 setbuf(daemon->out, NULL); 1229 return 0; 1230} 1231 1232static int setup_signalfd(struct daemon *daemon) 1233{ 1234 sigset_t mask; 1235 1236 sigemptyset(&mask); 1237 sigaddset(&mask, SIGCHLD); 1238 1239 if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1) 1240 return -1; 1241 1242 daemon->signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC); 1243 return daemon->signal_fd; 1244} 1245 1246static int __cmd_start(struct daemon *daemon, struct option parent_options[], 1247 int argc, const char **argv) 1248{ 1249 bool foreground = false; 1250 struct option start_options[] = { 1251 OPT_BOOLEAN('f', "foreground", &foreground, "stay on console"), 1252 OPT_PARENT(parent_options), 1253 OPT_END() 1254 }; 1255 int sock_fd = -1, conf_fd = -1, signal_fd = -1; 1256 int sock_pos, file_pos, signal_pos; 1257 struct fdarray fda; 1258 int err = 0; 1259 1260 argc = parse_options(argc, argv, start_options, daemon_usage, 0); 1261 if (argc) 1262 usage_with_options(daemon_usage, start_options); 1263 1264 daemon->start = time(NULL); 1265 1266 if (setup_config(daemon)) { 1267 pr_err("failed: config not found\n"); 1268 return -1; 1269 } 1270 1271 if (setup_server_config(daemon)) 1272 return -1; 1273 1274 if (foreground && check_lock(daemon)) 1275 return -1; 1276 1277 if (!foreground) { 1278 err = go_background(daemon); 1279 if (err) { 1280 /* original process, exit normally */ 1281 if (err == 1) 1282 err = 0; 1283 daemon__exit(daemon); 1284 return err; 1285 } 1286 } 1287 1288 debug_set_file(daemon->out); 1289 debug_set_display_time(true); 1290 1291 pr_info("daemon started (pid %d)\n", getpid()); 1292 1293 fdarray__init(&fda, 3); 1294 1295 sock_fd = setup_server_socket(daemon); 1296 if (sock_fd < 0) 1297 goto out; 1298 1299 conf_fd = setup_config_changes(daemon); 1300 if (conf_fd < 0) 1301 goto out; 1302 1303 signal_fd = setup_signalfd(daemon); 1304 if (signal_fd < 0) 1305 goto out; 1306 1307 sock_pos = fdarray__add(&fda, sock_fd, POLLIN|POLLERR|POLLHUP, 0); 1308 if (sock_pos < 0) 1309 goto out; 1310 1311 file_pos = fdarray__add(&fda, conf_fd, POLLIN|POLLERR|POLLHUP, 0); 1312 if (file_pos < 0) 1313 goto out; 1314 1315 signal_pos = fdarray__add(&fda, signal_fd, POLLIN|POLLERR|POLLHUP, 0); 1316 if (signal_pos < 0) 1317 goto out; 1318 1319 signal(SIGINT, sig_handler); 1320 signal(SIGTERM, sig_handler); 1321 signal(SIGPIPE, SIG_IGN); 1322 1323 while (!done && !err) { 1324 err = daemon__reconfig(daemon); 1325 1326 if (!err && fdarray__poll(&fda, -1)) { 1327 bool reconfig = false; 1328 1329 if (fda.entries[sock_pos].revents & POLLIN) 1330 err = handle_server_socket(daemon, sock_fd); 1331 if (fda.entries[file_pos].revents & POLLIN) 1332 err = handle_config_changes(daemon, conf_fd, &reconfig); 1333 if (fda.entries[signal_pos].revents & POLLIN) 1334 err = handle_signalfd(daemon) < 0; 1335 1336 if (reconfig) 1337 err = setup_server_config(daemon); 1338 } 1339 } 1340 1341out: 1342 fdarray__exit(&fda); 1343 1344 daemon__kill(daemon); 1345 daemon__exit(daemon); 1346 1347 if (sock_fd != -1) 1348 close(sock_fd); 1349 if (conf_fd != -1) 1350 close(conf_fd); 1351 if (signal_fd != -1) 1352 close(signal_fd); 1353 1354 pr_info("daemon exited\n"); 1355 fclose(daemon->out); 1356 return err; 1357} 1358 1359static int send_cmd(struct daemon *daemon, union cmd *cmd) 1360{ 1361 int ret = -1, fd; 1362 char *line = NULL; 1363 size_t len = 0; 1364 ssize_t nread; 1365 FILE *in = NULL; 1366 1367 if (setup_client_config(daemon)) 1368 return -1; 1369 1370 fd = setup_client_socket(daemon); 1371 if (fd < 0) 1372 return -1; 1373 1374 if (sizeof(*cmd) != writen(fd, cmd, sizeof(*cmd))) { 1375 perror("failed: write"); 1376 goto out; 1377 } 1378 1379 in = fdopen(fd, "r"); 1380 if (!in) { 1381 perror("failed: fdopen"); 1382 goto out; 1383 } 1384 1385 while ((nread = getline(&line, &len, in)) != -1) { 1386 if (fwrite(line, nread, 1, stdout) != 1) 1387 goto out_fclose; 1388 fflush(stdout); 1389 } 1390 1391 ret = 0; 1392out_fclose: 1393 fclose(in); 1394 free(line); 1395out: 1396 /* If in is defined, then fd is closed via fclose. */ 1397 if (!in) 1398 close(fd); 1399 return ret; 1400} 1401 1402static int send_cmd_list(struct daemon *daemon) 1403{ 1404 union cmd cmd; 1405 1406 memset(&cmd, 0, sizeof(cmd)); 1407 cmd.list.cmd = CMD_LIST; 1408 cmd.list.verbose = verbose; 1409 cmd.list.csv_sep = daemon->csv_sep ? *daemon->csv_sep : 0; 1410 1411 return send_cmd(daemon, &cmd); 1412} 1413 1414static int __cmd_signal(struct daemon *daemon, struct option parent_options[], 1415 int argc, const char **argv) 1416{ 1417 const char *name = "all"; 1418 struct option start_options[] = { 1419 OPT_STRING(0, "session", &name, "session", 1420 "Sent signal to specific session"), 1421 OPT_PARENT(parent_options), 1422 OPT_END() 1423 }; 1424 union cmd cmd; 1425 1426 argc = parse_options(argc, argv, start_options, daemon_usage, 0); 1427 if (argc) 1428 usage_with_options(daemon_usage, start_options); 1429 1430 if (setup_config(daemon)) { 1431 pr_err("failed: config not found\n"); 1432 return -1; 1433 } 1434 1435 memset(&cmd, 0, sizeof(cmd)); 1436 cmd.signal.cmd = CMD_SIGNAL, 1437 cmd.signal.sig = SIGUSR2; 1438 strncpy(cmd.signal.name, name, sizeof(cmd.signal.name) - 1); 1439 1440 return send_cmd(daemon, &cmd); 1441} 1442 1443static int __cmd_stop(struct daemon *daemon, struct option parent_options[], 1444 int argc, const char **argv) 1445{ 1446 struct option start_options[] = { 1447 OPT_PARENT(parent_options), 1448 OPT_END() 1449 }; 1450 union cmd cmd; 1451 1452 argc = parse_options(argc, argv, start_options, daemon_usage, 0); 1453 if (argc) 1454 usage_with_options(daemon_usage, start_options); 1455 1456 if (setup_config(daemon)) { 1457 pr_err("failed: config not found\n"); 1458 return -1; 1459 } 1460 1461 memset(&cmd, 0, sizeof(cmd)); 1462 cmd.cmd = CMD_STOP; 1463 return send_cmd(daemon, &cmd); 1464} 1465 1466static int __cmd_ping(struct daemon *daemon, struct option parent_options[], 1467 int argc, const char **argv) 1468{ 1469 const char *name = "all"; 1470 struct option ping_options[] = { 1471 OPT_STRING(0, "session", &name, "session", 1472 "Ping to specific session"), 1473 OPT_PARENT(parent_options), 1474 OPT_END() 1475 }; 1476 union cmd cmd; 1477 1478 argc = parse_options(argc, argv, ping_options, daemon_usage, 0); 1479 if (argc) 1480 usage_with_options(daemon_usage, ping_options); 1481 1482 if (setup_config(daemon)) { 1483 pr_err("failed: config not found\n"); 1484 return -1; 1485 } 1486 1487 memset(&cmd, 0, sizeof(cmd)); 1488 cmd.cmd = CMD_PING; 1489 scnprintf(cmd.ping.name, sizeof(cmd.ping.name), "%s", name); 1490 return send_cmd(daemon, &cmd); 1491} 1492 1493static char *alloc_perf_exe_path(void) 1494{ 1495 char path[PATH_MAX]; 1496 1497 perf_exe(path, sizeof(path)); 1498 return strdup(path); 1499} 1500 1501int cmd_daemon(int argc, const char **argv) 1502{ 1503 struct option daemon_options[] = { 1504 OPT_INCR('v', "verbose", &verbose, "be more verbose"), 1505 OPT_STRING(0, "config", &__daemon.config, 1506 "config file", "config file path"), 1507 OPT_STRING(0, "base", &__daemon.base_user, 1508 "directory", "base directory"), 1509 OPT_STRING_OPTARG('x', "field-separator", &__daemon.csv_sep, 1510 "field separator", "print counts with custom separator", ","), 1511 OPT_END() 1512 }; 1513 int ret = -1; 1514 1515 __daemon.perf = alloc_perf_exe_path(); 1516 if (!__daemon.perf) 1517 return -ENOMEM; 1518 1519 __daemon.out = stdout; 1520 1521 argc = parse_options(argc, argv, daemon_options, daemon_usage, 1522 PARSE_OPT_STOP_AT_NON_OPTION); 1523 1524 if (argc) { 1525 if (!strcmp(argv[0], "start")) 1526 ret = __cmd_start(&__daemon, daemon_options, argc, argv); 1527 else if (!strcmp(argv[0], "signal")) 1528 ret = __cmd_signal(&__daemon, daemon_options, argc, argv); 1529 else if (!strcmp(argv[0], "stop")) 1530 ret = __cmd_stop(&__daemon, daemon_options, argc, argv); 1531 else if (!strcmp(argv[0], "ping")) 1532 ret = __cmd_ping(&__daemon, daemon_options, argc, argv); 1533 else 1534 pr_err("failed: unknown command '%s'\n", argv[0]); 1535 } else { 1536 ret = setup_config(&__daemon); 1537 if (ret) 1538 pr_err("failed: config not found\n"); 1539 else 1540 ret = send_cmd_list(&__daemon); 1541 } 1542 zfree(&__daemon.perf); 1543 return ret; 1544} 1545