src/bin/lttng/commands/enable_channels.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License, version 2 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _LGPL_SOURCE
  19 #include <popt.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <sys/stat.h>
  24 #include <sys/types.h>
  25 #include <unistd.h>
  26 #include <inttypes.h>
  27 #include <assert.h>
  28 #include <ctype.h>
  29
  30 #include <common/sessiond-comm/sessiond-comm.h>
  31 #include <common/utils.h>
  32 #include <common/mi-lttng.h>
  33
  34 #include "../command.h"
  35 #include "../utils.h"
  36
  37
  38 static char *opt_channels;
  39 static int opt_kernel;
  40 static char *opt_session_name;
  41 static int opt_userspace;
  42 static struct lttng_channel chan;
  43 static char *opt_output;
  44 static int opt_buffer_uid;
  45 static int opt_buffer_pid;
  46 static int opt_buffer_global;
  47
  48 static struct mi_writer *writer;
  49
  50 enum {
  51         OPT_HELP = 1,
  52         OPT_DISCARD,
  53         OPT_OVERWRITE,
  54         OPT_SUBBUF_SIZE,
  55         OPT_NUM_SUBBUF,
  56         OPT_SWITCH_TIMER,
  57         OPT_READ_TIMER,
  58         OPT_USERSPACE,
  59         OPT_LIST_OPTIONS,
  60         OPT_TRACEFILE_SIZE,
  61         OPT_TRACEFILE_COUNT,
  62 };
  63
  64 static struct lttng_handle *handle;
  65
  66 const char *output_mmap = "mmap";
  67 const char *output_splice = "splice";
  68
  69 static struct poptOption long_options[] = {
  70         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  71         {"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  72         {"session",        's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  73         {"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  74         {"userspace",      'u', POPT_ARG_NONE, 0, OPT_USERSPACE, 0, 0},
  75         {"discard",        0,   POPT_ARG_NONE, 0, OPT_DISCARD, 0, 0},
  76         {"overwrite",      0,   POPT_ARG_NONE, 0, OPT_OVERWRITE, 0, 0},
  77         {"subbuf-size",    0,   POPT_ARG_STRING, 0, OPT_SUBBUF_SIZE, 0, 0},
  78         {"num-subbuf",     0,   POPT_ARG_INT, 0, OPT_NUM_SUBBUF, 0, 0},
  79         {"switch-timer",   0,   POPT_ARG_INT, 0, OPT_SWITCH_TIMER, 0, 0},
  80         {"read-timer",     0,   POPT_ARG_INT, 0, OPT_READ_TIMER, 0, 0},
  81         {"list-options",   0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  82         {"output",         0,   POPT_ARG_STRING, &opt_output, 0, 0, 0},
  83         {"buffers-uid",    0,   POPT_ARG_VAL, &opt_buffer_uid, 1, 0, 0},
  84         {"buffers-pid",    0,   POPT_ARG_VAL, &opt_buffer_pid, 1, 0, 0},
  85         {"buffers-global", 0,   POPT_ARG_VAL, &opt_buffer_global, 1, 0, 0},
  86         {"tracefile-size", 'C',   POPT_ARG_INT, 0, OPT_TRACEFILE_SIZE, 0, 0},
  87         {"tracefile-count", 'W',   POPT_ARG_INT, 0, OPT_TRACEFILE_COUNT, 0, 0},
  88         {0, 0, 0, 0, 0, 0, 0}
  89 };
  90
  91 /*
  92  * Set default attributes depending on those already defined from the command
  93  * line.
  94  */
  95 static void set_default_attr(struct lttng_domain *dom)
  96 {
  97         struct lttng_channel_attr default_attr;
  98
  99         /* Set attributes */
 100         lttng_channel_set_default_attr(dom, &default_attr);
 101
 102         if (chan.attr.overwrite == -1) {
 103                 chan.attr.overwrite = default_attr.overwrite;
 104         }
 105         if (chan.attr.subbuf_size == -1) {
 106                 chan.attr.subbuf_size = default_attr.subbuf_size;
 107         }
 108         if (chan.attr.num_subbuf == -1) {
 109                 chan.attr.num_subbuf = default_attr.num_subbuf;
 110         }
 111         if (chan.attr.switch_timer_interval == -1) {
 112                 chan.attr.switch_timer_interval = default_attr.switch_timer_interval;
 113         }
 114         if (chan.attr.read_timer_interval == -1) {
 115                 chan.attr.read_timer_interval = default_attr.read_timer_interval;
 116         }
 117         if ((int) chan.attr.output == -1) {
 118                 chan.attr.output = default_attr.output;
 119         }
 120         if (chan.attr.tracefile_count == -1) {
 121                 chan.attr.tracefile_count = default_attr.tracefile_count;
 122         }
 123         if (chan.attr.tracefile_size == -1) {
 124                 chan.attr.tracefile_size = default_attr.tracefile_size;
 125         }
 126 }
 127
 128 /*
 129  * Adding channel using the lttng API.
 130  */
 131 static int enable_channel(char *session_name)
 132 {
 133         int ret = CMD_SUCCESS, warn = 0, error = 0, success = 0;
 134         char *channel_name;
 135         struct lttng_domain dom;
 136
 137         memset(&dom, 0, sizeof(dom));
 138
 139         /* Create lttng domain */
 140         if (opt_kernel) {
 141                 dom.type = LTTNG_DOMAIN_KERNEL;
 142                 dom.buf_type = LTTNG_BUFFER_GLOBAL;
 143                 if (opt_buffer_uid || opt_buffer_pid) {
 144                         ERR("Buffer type not supported for domain -k");
 145                         ret = CMD_ERROR;
 146                         goto error;
 147                 }
 148         } else if (opt_userspace) {
 149                 dom.type = LTTNG_DOMAIN_UST;
 150                 if (opt_buffer_pid) {
 151                         dom.buf_type = LTTNG_BUFFER_PER_PID;
 152                 } else {
 153                         if (opt_buffer_global) {
 154                                 ERR("Buffer type not supported for domain -u");
 155                                 ret = CMD_ERROR;
 156                                 goto error;
 157                         }
 158                         dom.buf_type = LTTNG_BUFFER_PER_UID;
 159                 }
 160         } else {
 161                 /* Checked by the caller. */
 162                 assert(0);
 163         }
 164
 165         set_default_attr(&dom);
 166
 167         if (chan.attr.tracefile_size == 0 && chan.attr.tracefile_count) {
 168                 ERR("Missing option --tracefile-size. "
 169                                 "A file count without a size won't do anything.");
 170                 ret = CMD_ERROR;
 171                 goto error;
 172         }
 173
 174         if ((chan.attr.tracefile_size > 0) &&
 175                         (chan.attr.tracefile_size < chan.attr.subbuf_size)) {
 176                 WARN("Tracefile size rounded up from (%" PRIu64 ") to subbuffer size (%" PRIu64 ")",
 177                                 chan.attr.tracefile_size, chan.attr.subbuf_size);
 178                 chan.attr.tracefile_size = chan.attr.subbuf_size;
 179         }
 180
 181         /* Setting channel output */
 182         if (opt_output) {
 183                 if (!strncmp(output_mmap, opt_output, strlen(output_mmap))) {
 184                         chan.attr.output = LTTNG_EVENT_MMAP;
 185                 } else if (!strncmp(output_splice, opt_output, strlen(output_splice))) {
 186                         chan.attr.output = LTTNG_EVENT_SPLICE;
 187                 } else {
 188                         ERR("Unknown output type %s. Possible values are: %s, %s\n",
 189                                         opt_output, output_mmap, output_splice);
 190                         ret = CMD_ERROR;
 191                         goto error;
 192                 }
 193         }
 194
 195         handle = lttng_create_handle(session_name, &dom);
 196         if (handle == NULL) {
 197                 ret = -1;
 198                 goto error;
 199         }
 200
 201         /* Mi open channels element */
 202         if (lttng_opt_mi) {
 203                 assert(writer);
 204                 ret = mi_lttng_channels_open(writer);
 205                 if (ret) {
 206                         ret = CMD_ERROR;
 207                         goto error;
 208                 }
 209         }
 210
 211         /* Strip channel list (format: chan1,chan2,...) */
 212         channel_name = strtok(opt_channels, ",");
 213         while (channel_name != NULL) {
 214                 /* Validate channel name's length */
 215                 if (strlen(channel_name) >= NAME_MAX) {
 216                         ERR("Channel name is too long (max. %zu characters)",
 217                                         sizeof(chan.name) - 1);
 218                         error = 1;
 219                         goto skip_enable;
 220                 }
 221
 222                 /* Copy channel name */
 223                 strcpy(chan.name, channel_name);
 224
 225                 DBG("Enabling channel %s", channel_name);
 226
 227                 ret = lttng_enable_channel(handle, &chan);
 228                 if (ret < 0) {
 229                         success = 0;
 230                         switch (-ret) {
 231                         case LTTNG_ERR_KERN_CHAN_EXIST:
 232                         case LTTNG_ERR_UST_CHAN_EXIST:
 233                         case LTTNG_ERR_CHAN_EXIST:
 234                                 WARN("Channel %s: %s (session %s)", channel_name,
 235                                                 lttng_strerror(ret), session_name);
 236                                 warn = 1;
 237                                 break;
 238                         case LTTNG_ERR_INVALID_CHANNEL_NAME:
 239                                 ERR("Invalid channel name: \"%s\". "
 240                                     "Channel names may not start with '.', and "
 241                                     "may not contain '/'.", channel_name);
 242                                 error = 1;
 243                                 break;
 244                         default:
 245                                 ERR("Channel %s: %s (session %s)", channel_name,
 246                                                 lttng_strerror(ret), session_name);
 247                                 error = 1;
 248                                 break;
 249                         }
 250                 } else {
 251                         MSG("%s channel %s enabled for session %s",
 252                                         get_domain_str(dom.type), channel_name, session_name);
 253                         success = 1;
 254                 }
 255
 256 skip_enable:
 257                 if (lttng_opt_mi) {
 258                         /* Mi print the channel element and leave it open */
 259                         ret = mi_lttng_channel(writer, &chan, 1);
 260                         if (ret) {
 261                                 ret = CMD_ERROR;
 262                                 goto error;
 263                         }
 264
 265                         /* Individual Success ? */
 266                         ret = mi_lttng_writer_write_element_bool(writer,
 267                                         mi_lttng_element_command_success, success);
 268                         if (ret) {
 269                                 ret = CMD_ERROR;
 270                                 goto error;
 271                         }
 272
 273                         /* Close channel element */
 274                         ret = mi_lttng_writer_close_element(writer);
 275                         if (ret) {
 276                                 ret = CMD_ERROR;
 277                                 goto error;
 278                         }
 279                 }
 280
 281                 /* Next channel */
 282                 channel_name = strtok(NULL, ",");
 283         }
 284
 285         if (lttng_opt_mi) {
 286                 /* Close channels element */
 287                 ret = mi_lttng_writer_close_element(writer);
 288                 if (ret) {
 289                         ret = CMD_ERROR;
 290                         goto error;
 291                 }
 292         }
 293
 294         ret = CMD_SUCCESS;
 295
 296 error:
 297         /* If more important error happen bypass the warning */
 298         if (!ret && warn) {
 299                 ret = CMD_WARNING;
 300         }
 301         /* If more important error happen bypass the warning */
 302         if (!ret && error) {
 303                 ret = CMD_ERROR;
 304         }
 305
 306         lttng_destroy_handle(handle);
 307
 308         return ret;
 309 }
 310
 311 /*
 312  * Default value for channel configuration.
 313  */
 314 static void init_channel_config(void)
 315 {
 316         /*
 317          * Put -1 everywhere so we can identify those set by the command line and
 318          * those needed to be set by the default values.
 319          */
 320         memset(&chan.attr, -1, sizeof(chan.attr));
 321         chan.attr.extended.ptr = NULL;
 322 }
 323
 324 /*
 325  * Add channel to trace session
 326  */
 327 int cmd_enable_channels(int argc, const char **argv)
 328 {
 329         int opt, ret = CMD_SUCCESS, command_ret = CMD_SUCCESS, success = 1;
 330         static poptContext pc;
 331         char *session_name = NULL;
 332         char *opt_arg = NULL;
 333         const char *leftover = NULL;
 334
 335         init_channel_config();
 336
 337         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 338         poptReadDefaultConfig(pc, 0);
 339
 340         while ((opt = poptGetNextOpt(pc)) != -1) {
 341                 switch (opt) {
 342                 case OPT_HELP:
 343                         SHOW_HELP();
 344                         goto end;
 345                 case OPT_DISCARD:
 346                         chan.attr.overwrite = 0;
 347                         DBG("Channel set to discard");
 348                         break;
 349                 case OPT_OVERWRITE:
 350                         chan.attr.overwrite = 1;
 351                         DBG("Channel set to overwrite");
 352                         break;
 353                 case OPT_SUBBUF_SIZE:
 354                 {
 355                         uint64_t rounded_size;
 356                         int order;
 357
 358                         /* Parse the size */
 359                         opt_arg = poptGetOptArg(pc);
 360                         if (utils_parse_size_suffix(opt_arg, &chan.attr.subbuf_size) < 0 || !chan.attr.subbuf_size) {
 361                                 ERR("Wrong value in --subbuf-size parameter: %s", opt_arg);
 362                                 ret = CMD_ERROR;
 363                                 goto end;
 364                         }
 365
 366                         order = get_count_order_u64(chan.attr.subbuf_size);
 367                         assert(order >= 0);
 368                         rounded_size = 1ULL << order;
 369                         if (rounded_size < chan.attr.subbuf_size) {
 370                                 ERR("The subbuf size (%" PRIu64 ") is rounded and overflows!",
 371                                                 chan.attr.subbuf_size);
 372                                 ret = CMD_ERROR;
 373                                 goto end;
 374                         }
 375
 376                         if (rounded_size != chan.attr.subbuf_size) {
 377                                 WARN("The subbuf size (%" PRIu64 ") is rounded to the next power of 2 (%" PRIu64 ")",
 378                                                 chan.attr.subbuf_size, rounded_size);
 379                                 chan.attr.subbuf_size = rounded_size;
 380                         }
 381
 382                         /* Should now be power of 2 */
 383                         assert(!((chan.attr.subbuf_size - 1) & chan.attr.subbuf_size));
 384
 385                         DBG("Channel subbuf size set to %" PRIu64, chan.attr.subbuf_size);
 386                         break;
 387                 }
 388                 case OPT_NUM_SUBBUF:
 389                 {
 390                         uint64_t rounded_size;
 391                         int order;
 392
 393                         errno = 0;
 394                         opt_arg = poptGetOptArg(pc);
 395                         chan.attr.num_subbuf = strtoull(opt_arg, NULL, 0);
 396                         if (errno != 0 || !chan.attr.num_subbuf || !isdigit(opt_arg[0])) {
 397                                 ERR("Wrong value in --num-subbuf parameter: %s", opt_arg);
 398                                 ret = CMD_ERROR;
 399                                 goto end;
 400                         }
 401
 402                         order = get_count_order_u64(chan.attr.num_subbuf);
 403                         assert(order >= 0);
 404                         rounded_size = 1ULL << order;
 405                         if (rounded_size < chan.attr.num_subbuf) {
 406                                 ERR("The number of subbuffers (%" PRIu64 ") is rounded and overflows!",
 407                                                 chan.attr.num_subbuf);
 408                                 ret = CMD_ERROR;
 409                                 goto end;
 410                         }
 411
 412                         if (rounded_size != chan.attr.num_subbuf) {
 413                                 WARN("The number of subbuffers (%" PRIu64 ") is rounded to the next power of 2 (%" PRIu64 ")",
 414                                                 chan.attr.num_subbuf, rounded_size);
 415                                 chan.attr.num_subbuf = rounded_size;
 416                         }
 417
 418                         /* Should now be power of 2 */
 419                         assert(!((chan.attr.num_subbuf - 1) & chan.attr.num_subbuf));
 420
 421                         DBG("Channel subbuf num set to %" PRIu64, chan.attr.num_subbuf);
 422                         break;
 423                 }
 424                 case OPT_SWITCH_TIMER:
 425                 {
 426                         unsigned long v;
 427
 428                         errno = 0;
 429                         opt_arg = poptGetOptArg(pc);
 430                         v = strtoul(opt_arg, NULL, 0);
 431                         if (errno != 0 || !isdigit(opt_arg[0])) {
 432                                 ERR("Wrong value in --switch-timer parameter: %s", opt_arg);
 433                                 ret = CMD_ERROR;
 434                                 goto end;
 435                         }
 436                         if (v != (uint32_t) v) {
 437                                 ERR("32-bit overflow in --switch-timer parameter: %s", opt_arg);
 438                                 ret = CMD_ERROR;
 439                                 goto end;
 440                         }
 441                         chan.attr.switch_timer_interval = (uint32_t) v;
 442                         DBG("Channel switch timer interval set to %d", chan.attr.switch_timer_interval);
 443                         break;
 444                 }
 445                 case OPT_READ_TIMER:
 446                 {
 447                         unsigned long v;
 448
 449                         errno = 0;
 450                         opt_arg = poptGetOptArg(pc);
 451                         v = strtoul(opt_arg, NULL, 0);
 452                         if (errno != 0 || !isdigit(opt_arg[0])) {
 453                                 ERR("Wrong value in --read-timer parameter: %s", opt_arg);
 454                                 ret = CMD_ERROR;
 455                                 goto end;
 456                         }
 457                         if (v != (uint32_t) v) {
 458                                 ERR("32-bit overflow in --read-timer parameter: %s", opt_arg);
 459                                 ret = CMD_ERROR;
 460                                 goto end;
 461                         }
 462                         chan.attr.read_timer_interval = (uint32_t) v;
 463                         DBG("Channel read timer interval set to %d", chan.attr.read_timer_interval);
 464                         break;
 465                 }
 466                 case OPT_USERSPACE:
 467                         opt_userspace = 1;
 468                         break;
 469                 case OPT_TRACEFILE_SIZE:
 470                         opt_arg = poptGetOptArg(pc);
 471                         if (utils_parse_size_suffix(opt_arg, &chan.attr.tracefile_size) < 0) {
 472                                 ERR("Wrong value in --tracefile-size parameter: %s", opt_arg);
 473                                 ret = CMD_ERROR;
 474                                 goto end;
 475                         }
 476                         DBG("Maximum tracefile size set to %" PRIu64,
 477                                         chan.attr.tracefile_size);
 478                         break;
 479                 case OPT_TRACEFILE_COUNT:
 480                 {
 481                         unsigned long v;
 482
 483                         errno = 0;
 484                         opt_arg = poptGetOptArg(pc);
 485                         v = strtoul(opt_arg, NULL, 0);
 486                         if (errno != 0 || !isdigit(opt_arg[0])) {
 487                                 ERR("Wrong value in --tracefile-count parameter: %s", opt_arg);
 488                                 ret = CMD_ERROR;
 489                                 goto end;
 490                         }
 491                         if (v != (uint32_t) v) {
 492                                 ERR("32-bit overflow in --tracefile-count parameter: %s", opt_arg);
 493                                 ret = CMD_ERROR;
 494                                 goto end;
 495                         }
 496                         chan.attr.tracefile_count = (uint32_t) v;
 497                         DBG("Maximum tracefile count set to %" PRIu64,
 498                                         chan.attr.tracefile_count);
 499                         break;
 500                 }
 501                 case OPT_LIST_OPTIONS:
 502                         list_cmd_options(stdout, long_options);
 503                         goto end;
 504                 default:
 505                         ret = CMD_UNDEFINED;
 506                         goto end;
 507                 }
 508         }
 509
 510         ret = print_missing_or_multiple_domains(opt_kernel + opt_userspace);
 511         if (ret) {
 512                 ret = CMD_ERROR;
 513                 goto end;
 514         }
 515
 516         /* Mi check */
 517         if (lttng_opt_mi) {
 518                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 519                 if (!writer) {
 520                         ret = -LTTNG_ERR_NOMEM;
 521                         goto end;
 522                 }
 523
 524                 /* Open command element */
 525                 ret = mi_lttng_writer_command_open(writer,
 526                                 mi_lttng_element_command_enable_channels);
 527                 if (ret) {
 528                         ret = CMD_ERROR;
 529                         goto end;
 530                 }
 531
 532                 /* Open output element */
 533                 ret = mi_lttng_writer_open_element(writer,
 534                                 mi_lttng_element_command_output);
 535                 if (ret) {
 536                         ret = CMD_ERROR;
 537                         goto end;
 538                 }
 539         }
 540
 541         opt_channels = (char*) poptGetArg(pc);
 542         if (opt_channels == NULL) {
 543                 ERR("Missing channel name.\n");
 544                 ret = CMD_ERROR;
 545                 success = 0;
 546                 goto mi_closing;
 547         }
 548
 549         leftover = poptGetArg(pc);
 550         if (leftover) {
 551                 ERR("Unknown argument: %s", leftover);
 552                 ret = CMD_ERROR;
 553                 success = 0;
 554                 goto mi_closing;
 555         }
 556
 557         if (!opt_session_name) {
 558                 session_name = get_session_name();
 559                 if (session_name == NULL) {
 560                         command_ret = CMD_ERROR;
 561                         success = 0;
 562                         goto mi_closing;
 563                 }
 564         } else {
 565                 session_name = opt_session_name;
 566         }
 567
 568         command_ret = enable_channel(session_name);
 569         if (command_ret) {
 570                 success = 0;
 571         }
 572
 573 mi_closing:
 574         /* Mi closing */
 575         if (lttng_opt_mi) {
 576                 /* Close  output element */
 577                 ret = mi_lttng_writer_close_element(writer);
 578                 if (ret) {
 579                         goto end;
 580                 }
 581
 582                 /* Success ? */
 583                 ret = mi_lttng_writer_write_element_bool(writer,
 584                                 mi_lttng_element_command_success, success);
 585                 if (ret) {
 586                         goto end;
 587                 }
 588
 589                 /* Command element close */
 590                 ret = mi_lttng_writer_command_close(writer);
 591                 if (ret) {
 592                         goto end;
 593                 }
 594         }
 595
 596 end:
 597         /* Mi clean-up */
 598         if (writer && mi_lttng_writer_destroy(writer)) {
 599                 /* Preserve original error code */
 600                 ret = ret ? ret : LTTNG_ERR_MI_IO_FAIL;
 601         }
 602
 603         if (!opt_session_name && session_name) {
 604                 free(session_name);
 605         }
 606
 607         /* Overwrite ret if an error occurred when enable_channel */
 608         ret = command_ret ? command_ret : ret;
 609         poptFreeContext(pc);
 610         return ret;
 611 }