src/bin/lttng-sessiond/ust-consumer.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 <errno.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24
  25 #include <common/common.h>
  26 #include <common/consumer.h>
  27 #include <common/defaults.h>
  28
  29 #include "consumer.h"
  30 #include "ust-consumer.h"
  31
  32 /*
  33  * Send a single channel to the consumer using command ADD_CHANNEL.
  34  */
  35 static int send_channel(int sock, struct ust_app_channel *uchan)
  36 {
  37         int ret, fd;
  38         struct lttcomm_consumer_msg msg;
  39
  40         /* Safety net */
  41         assert(uchan);
  42
  43         if (sock < 0) {
  44                 ret = -EINVAL;
  45                 goto error;
  46         }
  47
  48         DBG2("Sending channel %s to UST consumer", uchan->name);
  49
  50         consumer_init_channel_comm_msg(&msg,
  51                         LTTNG_CONSUMER_ADD_CHANNEL,
  52                         uchan->obj->shm_fd,
  53                         uchan->attr.subbuf_size,
  54                         uchan->obj->memory_map_size,
  55                         uchan->name,
  56                         uchan->streams.count);
  57
  58         ret = consumer_send_channel(sock, &msg);
  59         if (ret < 0) {
  60                 goto error;
  61         }
  62
  63         fd = uchan->obj->shm_fd;
  64         ret = consumer_send_fds(sock, &fd, 1);
  65         if (ret < 0) {
  66                 goto error;
  67         }
  68
  69 error:
  70         return ret;
  71 }
  72
  73 /*
  74  * Send a single stream to the consumer using ADD_STREAM command.
  75  */
  76 static int send_channel_stream(int sock, struct ust_app_channel *uchan,
  77                 struct ust_app_session *usess, struct ltt_ust_stream *stream,
  78                 struct consumer_output *consumer, const char *pathname)
  79 {
  80         int ret, fds[2];
  81         struct lttcomm_consumer_msg msg;
  82
  83         /* Safety net */
  84         assert(uchan);
  85         assert(usess);
  86         assert(stream);
  87         assert(consumer);
  88
  89         DBG2("Sending stream %d of channel %s to kernel consumer",
  90                         stream->obj->shm_fd, uchan->name);
  91
  92         consumer_init_stream_comm_msg(&msg,
  93                         LTTNG_CONSUMER_ADD_STREAM,
  94                         uchan->obj->shm_fd,
  95                         stream->obj->shm_fd,
  96                         LTTNG_CONSUMER_ACTIVE_STREAM,
  97                         DEFAULT_UST_CHANNEL_OUTPUT,
  98                         stream->obj->memory_map_size,
  99                         usess->uid,
 100                         usess->gid,
 101                         consumer->net_seq_index,
 102                         0, /* Metadata flag unset */
 103                         stream->name,
 104                         pathname);
 105
 106         /* Send stream and file descriptor */
 107         fds[0] = stream->obj->shm_fd;
 108         fds[1] = stream->obj->wait_fd;
 109         ret = consumer_send_stream(sock, consumer, &msg, fds, 2);
 110         if (ret < 0) {
 111                 goto error;
 112         }
 113
 114 error:
 115         return ret;
 116 }
 117
 118 /*
 119  * Send all stream fds of UST channel to the consumer.
 120  */
 121 static int send_channel_streams(int sock,
 122                 struct ust_app_channel *uchan, struct ust_app_session *usess,
 123                 struct consumer_output *consumer)
 124 {
 125         int ret;
 126         char tmp_path[PATH_MAX];
 127         const char *pathname;
 128         struct ltt_ust_stream *stream, *tmp;
 129
 130         DBG("Sending streams of channel %s to UST consumer", uchan->name);
 131
 132         ret = send_channel(sock, uchan);
 133         if (ret < 0) {
 134                 goto error;
 135         }
 136
 137         /* Get the right path name destination */
 138         if (consumer->type == CONSUMER_DST_LOCAL) {
 139                 /* Set application path to the destination path */
 140                 ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s/%s",
 141                                 consumer->dst.trace_path, consumer->subdir, usess->path);
 142                 if (ret < 0) {
 143                         PERROR("snprintf stream path");
 144                         goto error;
 145                 }
 146                 pathname = tmp_path;
 147                 DBG3("UST local consumer tracefile path: %s", pathname);
 148         } else {
 149                 ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 150                                 consumer->subdir, usess->path);
 151                 if (ret < 0) {
 152                         PERROR("snprintf stream path");
 153                         goto error;
 154                 }
 155                 pathname = tmp_path;
 156                 DBG3("UST network consumer subdir path: %s", pathname);
 157         }
 158
 159         cds_list_for_each_entry_safe(stream, tmp, &uchan->streams.head, list) {
 160                 if (!stream->obj->shm_fd) {
 161                         continue;
 162                 }
 163
 164                 ret = send_channel_stream(sock, uchan, usess, stream, consumer,
 165                                 pathname);
 166                 if (ret < 0) {
 167                         goto error;
 168                 }
 169         }
 170
 171         DBG("UST consumer channel streams sent");
 172
 173         return 0;
 174
 175 error:
 176         return ret;
 177 }
 178
 179 /*
 180  * Sending metadata to the consumer with command ADD_CHANNEL and ADD_STREAM.
 181  */
 182 static int send_metadata(int sock, struct ust_app_session *usess,
 183                 struct consumer_output *consumer)
 184 {
 185         int ret, fd, fds[2];
 186         char tmp_path[PATH_MAX];
 187         const char *pathname;
 188         struct lttcomm_consumer_msg msg;
 189
 190         /* Safety net */
 191         assert(usess);
 192         assert(consumer);
 193
 194         if (sock < 0) {
 195                 ERR("Consumer socket is negative (%d)", sock);
 196                 return -EINVAL;
 197         }
 198
 199         if (usess->metadata->obj->shm_fd == 0) {
 200                 ERR("Metadata obj shm_fd is 0");
 201                 ret = -1;
 202                 goto error;
 203         }
 204
 205         DBG("UST consumer sending metadata stream fd");
 206
 207         consumer_init_channel_comm_msg(&msg,
 208                         LTTNG_CONSUMER_ADD_CHANNEL,
 209                         usess->metadata->obj->shm_fd,
 210                         usess->metadata->attr.subbuf_size,
 211                         usess->metadata->obj->memory_map_size,
 212                         "metadata",
 213                         1);
 214
 215         ret = consumer_send_channel(sock, &msg);
 216         if (ret < 0) {
 217                 goto error;
 218         }
 219
 220         /* Sending metadata shared memory fd */
 221         fd = usess->metadata->obj->shm_fd;
 222         ret = consumer_send_fds(sock, &fd, 1);
 223         if (ret < 0) {
 224                 goto error;
 225         }
 226
 227         /* Get correct path name destination */
 228         if (consumer->type == CONSUMER_DST_LOCAL) {
 229                 /* Set application path to the destination path */
 230                 ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s/%s",
 231                                 consumer->dst.trace_path, consumer->subdir, usess->path);
 232                 if (ret < 0) {
 233                         PERROR("snprintf stream path");
 234                         goto error;
 235                 }
 236                 pathname = tmp_path;
 237
 238                 /* Create directory */
 239                 ret = run_as_mkdir_recursive(pathname, S_IRWXU | S_IRWXG,
 240                                 usess->uid, usess->gid);
 241                 if (ret < 0) {
 242                         if (ret != -EEXIST) {
 243                                 ERR("Trace directory creation error");
 244                                 goto error;
 245                         }
 246                 }
 247         } else {
 248                 ret = snprintf(tmp_path, sizeof(tmp_path), "%s/%s",
 249                                 consumer->subdir, usess->path);
 250                 if (ret < 0) {
 251                         PERROR("snprintf metadata path");
 252                         goto error;
 253                 }
 254                 pathname = tmp_path;
 255         }
 256
 257         consumer_init_stream_comm_msg(&msg,
 258                         LTTNG_CONSUMER_ADD_STREAM,
 259                         usess->metadata->obj->shm_fd,
 260                         usess->metadata->stream_obj->shm_fd,
 261                         LTTNG_CONSUMER_ACTIVE_STREAM,
 262                         DEFAULT_UST_CHANNEL_OUTPUT,
 263                         usess->metadata->stream_obj->memory_map_size,
 264                         usess->uid,
 265                         usess->gid,
 266                         consumer->net_seq_index,
 267                         1, /* Flag metadata set */
 268                         "metadata",
 269                         pathname);
 270
 271         /* Send stream and file descriptor */
 272         fds[0] = usess->metadata->stream_obj->shm_fd;
 273         fds[1] = usess->metadata->stream_obj->wait_fd;
 274         ret = consumer_send_stream(sock, consumer, &msg, fds, 2);
 275         if (ret < 0) {
 276                 goto error;
 277         }
 278
 279 error:
 280         return ret;
 281 }
 282
 283 /*
 284  * Send all stream fds of the UST session to the consumer.
 285  */
 286 int ust_consumer_send_session(struct ust_app_session *usess,
 287                 struct consumer_output *consumer, struct consumer_socket *sock)
 288 {
 289         int ret = 0;
 290         struct lttng_ht_iter iter;
 291         struct ust_app_channel *ua_chan;
 292
 293         assert(usess);
 294
 295         if (consumer == NULL || sock == NULL) {
 296                 /* There is no consumer so just ignoring the command. */
 297                 DBG("UST consumer does not exist. Not sending streams");
 298                 return 0;
 299         }
 300
 301         DBG("Sending metadata stream fd to consumer on %d", sock->fd);
 302
 303         pthread_mutex_lock(sock->lock);
 304
 305         /* Sending metadata information to the consumer */
 306         ret = send_metadata(sock->fd, usess, consumer);
 307         if (ret < 0) {
 308                 goto error;
 309         }
 310
 311         /* Send each channel fd streams of session */
 312         rcu_read_lock();
 313         cds_lfht_for_each_entry(usess->channels->ht, &iter.iter, ua_chan,
 314                         node.node) {
 315                 /*
 316                  * Indicate that the channel was not created on the tracer side so skip
 317                  * sending unexisting streams.
 318                  */
 319                 if (ua_chan->obj == NULL) {
 320                         continue;
 321                 }
 322
 323                 ret = send_channel_streams(sock->fd, ua_chan, usess, consumer);
 324                 if (ret < 0) {
 325                         rcu_read_unlock();
 326                         goto error;
 327                 }
 328         }
 329         rcu_read_unlock();
 330
 331         DBG("consumer fds (metadata and channel streams) sent");
 332
 333         /* All good! */
 334         ret = 0;
 335
 336 error:
 337         pthread_mutex_unlock(sock->lock);
 338         return ret;
 339 }