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 _GNU_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 "../command.h"
  31 #include "../utils.h"
  32
  33 #include <src/common/sessiond-comm/sessiond-comm.h>
  34 #include <src/common/utils.h>
  35
  36 static char *opt_channels;
  37 static int opt_kernel;
  38 static char *opt_session_name;
  39 static int opt_userspace;
  40 static struct lttng_channel chan;
  41 static char *opt_output;
  42 static int opt_buffer_uid;
  43 static int opt_buffer_pid;
  44 static int opt_buffer_global;
  45
  46 enum {
  47         OPT_HELP = 1,
  48         OPT_DISCARD,
  49         OPT_OVERWRITE,
  50         OPT_SUBBUF_SIZE,
  51         OPT_NUM_SUBBUF,
  52         OPT_SWITCH_TIMER,
  53         OPT_READ_TIMER,
  54         OPT_USERSPACE,
  55         OPT_LIST_OPTIONS,
  56         OPT_TRACEFILE_SIZE,
  57         OPT_TRACEFILE_COUNT,
  58 };
  59
  60 static struct lttng_handle *handle;
  61
  62 const char *output_mmap = "mmap";
  63 const char *output_splice = "splice";
  64
  65 static struct poptOption long_options[] = {
  66         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  67         {"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  68         {"session",        's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  69         {"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  70         {"userspace",      'u', POPT_ARG_NONE, 0, OPT_USERSPACE, 0, 0},
  71         {"discard",        0,   POPT_ARG_NONE, 0, OPT_DISCARD, 0, 0},
  72         {"overwrite",      0,   POPT_ARG_NONE, 0, OPT_OVERWRITE, 0, 0},
  73         {"subbuf-size",    0,   POPT_ARG_STRING, 0, OPT_SUBBUF_SIZE, 0, 0},
  74         {"num-subbuf",     0,   POPT_ARG_INT, 0, OPT_NUM_SUBBUF, 0, 0},
  75         {"switch-timer",   0,   POPT_ARG_INT, 0, OPT_SWITCH_TIMER, 0, 0},
  76         {"read-timer",     0,   POPT_ARG_INT, 0, OPT_READ_TIMER, 0, 0},
  77         {"list-options",   0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  78         {"output",         0,   POPT_ARG_STRING, &opt_output, 0, 0, 0},
  79         {"buffers-uid",    0,   POPT_ARG_VAL, &opt_buffer_uid, 1, 0, 0},
  80         {"buffers-pid",    0,   POPT_ARG_VAL, &opt_buffer_pid, 1, 0, 0},
  81         {"buffers-global", 0,   POPT_ARG_VAL, &opt_buffer_global, 1, 0, 0},
  82         {"tracefile-size", 'C',   POPT_ARG_INT, 0, OPT_TRACEFILE_SIZE, 0, 0},
  83         {"tracefile-count", 'W',   POPT_ARG_INT, 0, OPT_TRACEFILE_COUNT, 0, 0},
  84         {0, 0, 0, 0, 0, 0, 0}
  85 };
  86
  87 /*
  88  * usage
  89  */
  90 static void usage(FILE *ofp)
  91 {
  92         fprintf(ofp, "usage: lttng enable-channel NAME[,NAME2,...] [-u|-k] [OPTIONS]\n");
  93         fprintf(ofp, "\n");
  94         fprintf(ofp, "Options:\n");
  95         fprintf(ofp, "  -h, --help               Show this help\n");
  96         fprintf(ofp, "      --list-options       Simple listing of options\n");
  97         fprintf(ofp, "  -s, --session NAME       Apply to session name\n");
  98         fprintf(ofp, "  -k, --kernel             Apply to the kernel tracer\n");
  99         fprintf(ofp, "  -u, --userspace          Apply to the user-space tracer\n");
 100         fprintf(ofp, "\n");
 101         fprintf(ofp, "Channel options:\n");
 102         fprintf(ofp, "      --discard            Discard event when buffers are full%s\n",
 103                 DEFAULT_CHANNEL_OVERWRITE ? "" : " (default)");
 104         fprintf(ofp, "      --overwrite          Flight recorder mode%s\n",
 105                 DEFAULT_CHANNEL_OVERWRITE ? " (default)" : "");
 106         fprintf(ofp, "      --subbuf-size SIZE   Subbuffer size in bytes {+k,+M,+G}\n");
 107         fprintf(ofp, "                               (default: %zu, kernel default: %zu)\n",
 108                 default_get_channel_subbuf_size(),
 109                 default_get_kernel_channel_subbuf_size());
 110         fprintf(ofp, "                               Rounded up to the next power of 2.\n");
 111         fprintf(ofp, "      --num-subbuf NUM     Number of subbufers\n");
 112         fprintf(ofp, "                               (default: %u)\n",
 113                 DEFAULT_CHANNEL_SUBBUF_NUM);
 114         fprintf(ofp, "                               Rounded up to the next power of 2.\n");
 115         fprintf(ofp, "      --switch-timer USEC  Switch timer interval in usec (default: %u)\n",
 116                 DEFAULT_CHANNEL_SWITCH_TIMER);
 117         fprintf(ofp, "      --read-timer USEC    Read timer interval in usec (UST default: %u, kernel default: %u)\n",
 118                 DEFAULT_UST_CHANNEL_READ_TIMER, DEFAULT_KERNEL_CHANNEL_READ_TIMER);
 119         fprintf(ofp, "      --output TYPE        Channel output type (Values: %s, %s)\n",
 120                         output_mmap, output_splice);
 121         fprintf(ofp, "      --buffers-uid        Use per UID buffer (-u only)\n");
 122         fprintf(ofp, "      --buffers-pid        Use per PID buffer (-u only)\n");
 123         fprintf(ofp, "      --buffers-global     Use shared buffer for the whole system (-k only)\n");
 124         fprintf(ofp, "  -C, --tracefile-size SIZE\n");
 125         fprintf(ofp, "                           Maximum size of each tracefile within a stream (in bytes).\n");
 126         fprintf(ofp, "  -W, --tracefile-count COUNT\n");
 127         fprintf(ofp, "                           Used in conjunction with -C option, this will limit the number\n");
 128         fprintf(ofp, "                           of files created to the specified count.\n");
 129         fprintf(ofp, "\n");
 130 }
 131
 132 /*
 133  * Set default attributes depending on those already defined from the command
 134  * line.
 135  */
 136 static void set_default_attr(struct lttng_domain *dom)
 137 {
 138         struct lttng_channel_attr default_attr;
 139
 140         /* Set attributes */
 141         lttng_channel_set_default_attr(dom, &default_attr);
 142
 143         if (chan.attr.overwrite == -1) {
 144                 chan.attr.overwrite = default_attr.overwrite;
 145         }
 146         if (chan.attr.subbuf_size == -1) {
 147                 chan.attr.subbuf_size = default_attr.subbuf_size;
 148         }
 149         if (chan.attr.num_subbuf == -1) {
 150                 chan.attr.num_subbuf = default_attr.num_subbuf;
 151         }
 152         if (chan.attr.switch_timer_interval == -1) {
 153                 chan.attr.switch_timer_interval = default_attr.switch_timer_interval;
 154         }
 155         if (chan.attr.read_timer_interval == -1) {
 156                 chan.attr.read_timer_interval = default_attr.read_timer_interval;
 157         }
 158         if (chan.attr.output == -1) {
 159                 chan.attr.output = default_attr.output;
 160         }
 161         if (chan.attr.tracefile_count == -1) {
 162                 chan.attr.tracefile_count = default_attr.tracefile_count;
 163         }
 164         if (chan.attr.tracefile_size == -1) {
 165                 chan.attr.tracefile_size = default_attr.tracefile_size;
 166         }
 167 }
 168
 169 /*
 170  * Adding channel using the lttng API.
 171  */
 172 static int enable_channel(char *session_name)
 173 {
 174         int ret = CMD_SUCCESS, warn = 0;
 175         char *channel_name;
 176         struct lttng_domain dom;
 177
 178         memset(&dom, 0, sizeof(dom));
 179
 180         /* Create lttng domain */
 181         if (opt_kernel) {
 182                 dom.type = LTTNG_DOMAIN_KERNEL;
 183                 dom.buf_type = LTTNG_BUFFER_GLOBAL;
 184                 if (opt_buffer_uid || opt_buffer_pid) {
 185                         ERR("Buffer type not supported for domain -k");
 186                         ret = CMD_ERROR;
 187                         goto error;
 188                 }
 189         } else if (opt_userspace) {
 190                 dom.type = LTTNG_DOMAIN_UST;
 191                 if (opt_buffer_uid) {
 192                         dom.buf_type = LTTNG_BUFFER_PER_UID;
 193                 } else {
 194                         if (opt_buffer_global) {
 195                                 ERR("Buffer type not supported for domain -u");
 196                                 ret = CMD_ERROR;
 197                                 goto error;
 198                         }
 199                         dom.buf_type = LTTNG_BUFFER_PER_PID;
 200                 }
 201         } else {
 202                 ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
 203                 ret = CMD_ERROR;
 204                 goto error;
 205         }
 206
 207         set_default_attr(&dom);
 208
 209         if ((chan.attr.tracefile_size > 0) &&
 210                         (chan.attr.tracefile_size < chan.attr.subbuf_size)) {
 211                 WARN("Tracefile size rounded up from (%" PRIu64 ") to subbuffer size (%" PRIu64 ")",
 212                                 chan.attr.tracefile_size, chan.attr.subbuf_size);
 213                 chan.attr.tracefile_size = chan.attr.subbuf_size;
 214         }
 215
 216         /* Setting channel output */
 217         if (opt_output) {
 218                 if (!strncmp(output_mmap, opt_output, strlen(output_mmap))) {
 219                         chan.attr.output = LTTNG_EVENT_MMAP;
 220                 } else if (!strncmp(output_splice, opt_output, strlen(output_splice))) {
 221                         chan.attr.output = LTTNG_EVENT_SPLICE;
 222                 } else {
 223                         ERR("Unknown output type %s. Possible values are: %s, %s\n",
 224                                         opt_output, output_mmap, output_splice);
 225                         usage(stderr);
 226                         ret = CMD_ERROR;
 227                         goto error;
 228                 }
 229         }
 230
 231         handle = lttng_create_handle(session_name, &dom);
 232         if (handle == NULL) {
 233                 ret = -1;
 234                 goto error;
 235         }
 236
 237         /* Strip channel list (format: chan1,chan2,...) */
 238         channel_name = strtok(opt_channels, ",");
 239         while (channel_name != NULL) {
 240                 /* Copy channel name and normalize it */
 241                 strncpy(chan.name, channel_name, NAME_MAX);
 242                 chan.name[NAME_MAX - 1] = '\0';
 243
 244                 DBG("Enabling channel %s", channel_name);
 245
 246                 ret = lttng_enable_channel(handle, &chan);
 247                 if (ret < 0) {
 248                         switch (-ret) {
 249                         case LTTNG_ERR_KERN_CHAN_EXIST:
 250                         case LTTNG_ERR_UST_CHAN_EXIST:
 251                                 WARN("Channel %s: %s (session %s)", channel_name,
 252                                                 lttng_strerror(ret), session_name);
 253                                 goto error;
 254                         default:
 255                                 ERR("Channel %s: %s (session %s)", channel_name,
 256                                                 lttng_strerror(ret), session_name);
 257                                 break;
 258                         }
 259                         warn = 1;
 260                 } else {
 261                         MSG("%s channel %s enabled for session %s",
 262                                         opt_kernel ? "Kernel" : "UST", channel_name,
 263                                         session_name);
 264                 }
 265
 266                 /* Next event */
 267                 channel_name = strtok(NULL, ",");
 268         }
 269
 270         ret = CMD_SUCCESS;
 271
 272 error:
 273         if (warn) {
 274                 ret = CMD_WARNING;
 275         }
 276
 277         lttng_destroy_handle(handle);
 278
 279         return ret;
 280 }
 281
 282 /*
 283  * Default value for channel configuration.
 284  */
 285 static void init_channel_config(void)
 286 {
 287         /*
 288          * Put -1 everywhere so we can identify those set by the command line and
 289          * those needed to be set by the default values.
 290          */
 291         memset(&chan.attr, -1, sizeof(chan.attr));
 292 }
 293
 294 /*
 295  * Add channel to trace session
 296  */
 297 int cmd_enable_channels(int argc, const char **argv)
 298 {
 299         int opt, ret = CMD_SUCCESS;
 300         static poptContext pc;
 301         char *session_name = NULL;
 302         char *opt_arg = NULL;
 303
 304         init_channel_config();
 305
 306         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 307         poptReadDefaultConfig(pc, 0);
 308
 309         while ((opt = poptGetNextOpt(pc)) != -1) {
 310                 switch (opt) {
 311                 case OPT_HELP:
 312                         usage(stdout);
 313                         goto end;
 314                 case OPT_DISCARD:
 315                         chan.attr.overwrite = 0;
 316                         DBG("Channel set to discard");
 317                         break;
 318                 case OPT_OVERWRITE:
 319                         chan.attr.overwrite = 1;
 320                         DBG("Channel set to overwrite");
 321                         break;
 322                 case OPT_SUBBUF_SIZE:
 323                 {
 324                         uint64_t rounded_size;
 325                         int order;
 326
 327                         /* Parse the size */
 328                         opt_arg = poptGetOptArg(pc);
 329                         if (utils_parse_size_suffix(opt_arg, &chan.attr.subbuf_size) < 0 || !chan.attr.subbuf_size) {
 330                                 ERR("Wrong value in --subbuf-size parameter: %s", opt_arg);
 331                                 ret = CMD_ERROR;
 332                                 goto end;
 333                         }
 334
 335                         order = get_count_order_u64(chan.attr.subbuf_size);
 336                         assert(order >= 0);
 337                         rounded_size = 1ULL << order;
 338                         if (rounded_size != chan.attr.subbuf_size) {
 339                                 WARN("The subbuf size (%" PRIu64 ") is rounded to the next power of 2 (%" PRIu64 ")",
 340                                                 chan.attr.subbuf_size, rounded_size);
 341                                 chan.attr.subbuf_size = rounded_size;
 342                         }
 343
 344                         /* Should now be power of 2 */
 345                         assert(!((chan.attr.subbuf_size - 1) & chan.attr.subbuf_size));
 346
 347                         DBG("Channel subbuf size set to %" PRIu64, chan.attr.subbuf_size);
 348                         break;
 349                 }
 350                 case OPT_NUM_SUBBUF:
 351                 {
 352                         uint64_t rounded_size;
 353                         int order;
 354
 355                         errno = 0;
 356                         opt_arg = poptGetOptArg(pc);
 357                         chan.attr.num_subbuf = strtoull(opt_arg, NULL, 0);
 358                         if (errno != 0 || !chan.attr.num_subbuf || !isdigit(opt_arg[0])) {
 359                                 ERR("Wrong value in --num-subbuf parameter: %s", opt_arg);
 360                                 ret = CMD_ERROR;
 361                                 goto end;
 362                         }
 363
 364                         order = get_count_order_u64(chan.attr.num_subbuf);
 365                         assert(order >= 0);
 366                         rounded_size = 1ULL << order;
 367                         if (rounded_size != chan.attr.num_subbuf) {
 368                                 WARN("The number of subbuffers (%" PRIu64 ") is rounded to the next power of 2 (%" PRIu64 ")",
 369                                                 chan.attr.num_subbuf, rounded_size);
 370                                 chan.attr.num_subbuf = rounded_size;
 371                         }
 372
 373                         /* Should now be power of 2 */
 374                         assert(!((chan.attr.num_subbuf - 1) & chan.attr.num_subbuf));
 375
 376                         DBG("Channel subbuf num set to %" PRIu64, chan.attr.num_subbuf);
 377                         break;
 378                 }
 379                 case OPT_SWITCH_TIMER:
 380                 {
 381                         unsigned long v;
 382
 383                         errno = 0;
 384                         opt_arg = poptGetOptArg(pc);
 385                         v = strtoul(opt_arg, NULL, 0);
 386                         if (errno != 0 || !isdigit(opt_arg[0])) {
 387                                 ERR("Wrong value in --switch-timer parameter: %s", opt_arg);
 388                                 ret = CMD_ERROR;
 389                                 goto end;
 390                         }
 391                         if (v != (uint32_t) v) {
 392                                 ERR("32-bit overflow in --switch-timer parameter: %s", opt_arg);
 393                                 ret = CMD_ERROR;
 394                                 goto end;
 395                         }
 396                         chan.attr.switch_timer_interval = (uint32_t) v;
 397                         DBG("Channel switch timer interval set to %d", chan.attr.switch_timer_interval);
 398                         break;
 399                 }
 400                 case OPT_READ_TIMER:
 401                 {
 402                         unsigned long v;
 403
 404                         errno = 0;
 405                         opt_arg = poptGetOptArg(pc);
 406                         v = strtoul(opt_arg, NULL, 0);
 407                         if (errno != 0 || !isdigit(opt_arg[0])) {
 408                                 ERR("Wrong value in --read-timer parameter: %s", opt_arg);
 409                                 ret = CMD_ERROR;
 410                                 goto end;
 411                         }
 412                         if (v != (uint32_t) v) {
 413                                 ERR("32-bit overflow in --read-timer parameter: %s", opt_arg);
 414                                 ret = CMD_ERROR;
 415                                 goto end;
 416                         }
 417                         chan.attr.read_timer_interval = (uint32_t) v;
 418                         DBG("Channel read timer interval set to %d", chan.attr.read_timer_interval);
 419                         break;
 420                 }
 421                 case OPT_USERSPACE:
 422                         opt_userspace = 1;
 423                         break;
 424                 case OPT_TRACEFILE_SIZE:
 425                         opt_arg = poptGetOptArg(pc);
 426                         if (utils_parse_size_suffix(opt_arg, &chan.attr.tracefile_size) < 0) {
 427                                 ERR("Wrong value in --tracefile-size parameter: %s", opt_arg);
 428                                 ret = CMD_ERROR;
 429                                 goto end;
 430                         }
 431                         DBG("Maximum tracefile size set to %" PRIu64,
 432                                         chan.attr.tracefile_size);
 433                         break;
 434                 case OPT_TRACEFILE_COUNT:
 435                 {
 436                         unsigned long v;
 437
 438                         errno = 0;
 439                         opt_arg = poptGetOptArg(pc);
 440                         v = strtoul(opt_arg, NULL, 0);
 441                         if (errno != 0 || !isdigit(opt_arg[0])) {
 442                                 ERR("Wrong value in --tracefile-count parameter: %s", opt_arg);
 443                                 ret = CMD_ERROR;
 444                                 goto end;
 445                         }
 446                         if (v != (uint32_t) v) {
 447                                 ERR("32-bit overflow in --tracefile-count parameter: %s", opt_arg);
 448                                 ret = CMD_ERROR;
 449                                 goto end;
 450                         }
 451                         chan.attr.tracefile_count = (uint32_t) v;
 452                         DBG("Maximum tracefile count set to %" PRIu64,
 453                                         chan.attr.tracefile_count);
 454                         break;
 455                 }
 456                 case OPT_LIST_OPTIONS:
 457                         list_cmd_options(stdout, long_options);
 458                         goto end;
 459                 default:
 460                         usage(stderr);
 461                         ret = CMD_UNDEFINED;
 462                         goto end;
 463                 }
 464         }
 465
 466         opt_channels = (char*) poptGetArg(pc);
 467         if (opt_channels == NULL) {
 468                 ERR("Missing channel name.\n");
 469                 usage(stderr);
 470                 ret = CMD_ERROR;
 471                 goto end;
 472         }
 473
 474         if (!opt_session_name) {
 475                 session_name = get_session_name();
 476                 if (session_name == NULL) {
 477                         ret = CMD_ERROR;
 478                         goto end;
 479                 }
 480         } else {
 481                 session_name = opt_session_name;
 482         }
 483
 484         ret = enable_channel(session_name);
 485
 486 end:
 487         if (!opt_session_name && session_name) {
 488                 free(session_name);
 489         }
 490         poptFreeContext(pc);
 491         return ret;
 492 }