src/bin/lttng-sessiond/rotate.c

   1 /*
   2  * Copyright (C) 2017 - Julien Desfossez <jdesfossez@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License, version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 51
  15  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _LGPL_SOURCE
  19 #include <lttng/trigger/trigger.h>
  20 #include <common/error.h>
  21 #include <common/config/session-config.h>
  22 #include <common/defaults.h>
  23 #include <common/utils.h>
  24 #include <common/futex.h>
  25 #include <common/align.h>
  26 #include <common/time.h>
  27 #include <common/hashtable/utils.h>
  28 #include <common/kernel-ctl/kernel-ctl.h>
  29 #include <sys/eventfd.h>
  30 #include <sys/stat.h>
  31 #include <time.h>
  32 #include <signal.h>
  33 #include <inttypes.h>
  34
  35 #include "session.h"
  36 #include "rotate.h"
  37 #include "rotation-thread.h"
  38 #include "lttng-sessiond.h"
  39 #include "health-sessiond.h"
  40 #include "cmd.h"
  41
  42 #include <urcu.h>
  43 #include <urcu/list.h>
  44 #include <urcu/rculfhash.h>
  45
  46 unsigned long hash_channel_key(struct rotation_channel_key *key)
  47 {
  48         return hash_key_u64(&key->key, lttng_ht_seed) ^ hash_key_ulong(
  49                 (void *) (unsigned long) key->domain, lttng_ht_seed);
  50 }
  51
  52 int rotate_add_channel_pending(uint64_t key, enum lttng_domain_type domain,
  53                 struct ltt_session *session)
  54 {
  55         int ret;
  56         struct rotation_channel_info *new_info;
  57         struct rotation_channel_key channel_key = { .key = key,
  58                 .domain = domain };
  59
  60         new_info = zmalloc(sizeof(struct rotation_channel_info));
  61         if (!new_info) {
  62                 goto error;
  63         }
  64
  65         new_info->channel_key.key = key;
  66         new_info->channel_key.domain = domain;
  67         new_info->session = session;
  68         cds_lfht_node_init(&new_info->rotate_channels_ht_node);
  69
  70         session->nr_chan_rotate_pending++;
  71         cds_lfht_add(channel_pending_rotate_ht,
  72                         hash_channel_key(&channel_key),
  73                         &new_info->rotate_channels_ht_node);
  74
  75         ret = 0;
  76         goto end;
  77
  78 error:
  79         ret = -1;
  80 end:
  81         return ret;
  82 }
  83
  84 int session_rename_chunk(struct ltt_session *session, char *current_path,
  85                 char *new_path, uint32_t create)
  86 {
  87         int ret;
  88         struct consumer_socket *socket;
  89         struct consumer_output *output;
  90         struct lttng_ht_iter iter;
  91         uid_t uid;
  92         gid_t gid;
  93
  94         /*
  95          * Either one of the sessions is enough to find the consumer_output
  96          * and uid/gid.
  97          */
  98         if (session->kernel_session) {
  99                 output = session->kernel_session->consumer;
 100                 uid = session->kernel_session->uid;
 101                 gid = session->kernel_session->gid;
 102         } else if (session->ust_session) {
 103                 output = session->ust_session->consumer;
 104                 uid = session->ust_session->uid;
 105                 gid = session->ust_session->gid;
 106         } else {
 107                 assert(0);
 108         }
 109
 110         if (!output || !output->socks) {
 111                 ERR("No consumer output found");
 112                 ret = -1;
 113                 goto end;
 114         }
 115
 116         rcu_read_lock();
 117         /*
 118          * We have to iterate to find a socket, but we only need to send the
 119          * rename command to one consumer, so we break after the first one.
 120          */
 121         cds_lfht_for_each_entry(output->socks->ht, &iter.iter, socket, node.node) {
 122                 pthread_mutex_lock(socket->lock);
 123                 ret = consumer_rotate_rename(socket, session->id, output,
 124                                 current_path, new_path, create, uid, gid);
 125                 pthread_mutex_unlock(socket->lock);
 126                 if (ret) {
 127                         ERR("Consumer rename chunk");
 128                         ret = -1;
 129                         rcu_read_unlock();
 130                         goto end;
 131                 }
 132                 break;
 133         }
 134         rcu_read_unlock();
 135
 136         ret = 0;
 137
 138 end:
 139         return ret;
 140 }
 141
 142 static
 143 int rename_first_chunk(struct ltt_session *session,
 144                 struct consumer_output *consumer, char *new_path)
 145 {
 146         int ret;
 147         char *tmppath = NULL, *tmppath2 = NULL;
 148
 149         tmppath = zmalloc(PATH_MAX * sizeof(char));
 150         if (!tmppath) {
 151                 ret = -LTTNG_ERR_NOMEM;
 152                 goto error;
 153         }
 154         tmppath2 = zmalloc(PATH_MAX * sizeof(char));
 155         if (!tmppath2) {
 156                 ret = -LTTNG_ERR_NOMEM;
 157                 goto error;
 158         }
 159
 160         /* Current domain path: <session>/kernel */
 161         snprintf(tmppath, PATH_MAX, "%s/%s",
 162                         consumer->dst.session_root_path, consumer->subdir);
 163         /* New domain path: <session>/<start-date>-<end-date>-<rotate-count>/kernel */
 164         snprintf(tmppath2, PATH_MAX, "%s/%s",
 165                         new_path, consumer->subdir);
 166         /*
 167          * Move the per-domain folder inside the first rotation
 168          * folder.
 169          */
 170         ret = session_rename_chunk(session, tmppath, tmppath2, 1);
 171         if (ret < 0) {
 172                 ERR("Rename first trace directory");
 173                 ret = -LTTNG_ERR_ROTATE_NO_DATA;
 174                 goto error;
 175         }
 176
 177         ret = 0;
 178
 179 error:
 180         free(tmppath);
 181         free(tmppath2);
 182
 183         return ret;
 184 }
 185
 186 int rename_complete_chunk(struct ltt_session *session, time_t ts)
 187 {
 188         struct tm *timeinfo;
 189         char datetime[16];
 190         char *new_path = NULL;
 191         int ret;
 192
 193         /*
 194          * TODO 2: on first rotate, the current_rotate_path is the session root
 195          * path, so move the kernel/ and ust/ folders inside the
 196          * "session->last_chunk_start_ts-now()"
 197          */
 198
 199         timeinfo = localtime(&ts);
 200         strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
 201
 202         new_path = zmalloc(PATH_MAX * sizeof(char));
 203         if (!new_path) {
 204                 session->rotate_status = LTTNG_ROTATE_ERROR;
 205                 ERR("Alloc new_path");
 206                 ret = -1;
 207                 goto end;
 208         }
 209
 210         if (session->rotate_count == 1) {
 211                 char start_time[16];
 212
 213                 timeinfo = localtime(&session->last_chunk_start_ts);
 214                 strftime(start_time, sizeof(start_time), "%Y%m%d-%H%M%S", timeinfo);
 215
 216                 /*
 217                  * On the first rotation, the current_rotate_path is the
 218                  * session_root_path, so we need to create the chunk folder
 219                  * and move the domain-specific folders inside it.
 220                  */
 221                 snprintf(new_path, PATH_MAX, "%s/%s-%s-%" PRIu64,
 222                                 session->rotation_chunk.current_rotate_path,
 223                                 start_time,
 224                                 datetime, session->rotate_count);
 225
 226                 if (session->kernel_session) {
 227                         fprintf(stderr, "rename %s/kernel to %s\n",
 228                                         session->rotation_chunk.current_rotate_path,
 229                                         new_path);
 230                         ret = rename_first_chunk(session,
 231                                         session->kernel_session->consumer,
 232                                         new_path);
 233                         if (ret) {
 234                                 ERR("Rename kernel session");
 235                                 /*
 236                                  * This is not a fatal error for the rotation
 237                                  * thread, we just need to inform the client
 238                                  * that a problem occurred with the rotation.
 239                                  * Returning 0, same for the other errors
 240                                  * below.
 241                                  */
 242                                 ret = 0;
 243                                 goto error;
 244                         }
 245                 }
 246                 if (session->ust_session) {
 247                         fprintf(stderr, "rename %s/kernel to %s\n",
 248                                         session->rotation_chunk.current_rotate_path,
 249                                         new_path);
 250                         ret = rename_first_chunk(session,
 251                                         session->ust_session->consumer,
 252                                         new_path);
 253                         if (ret) {
 254                                 ERR("Rename ust session");
 255                                 ret = 0;
 256                                 goto error;
 257                         }
 258                 }
 259         } else {
 260                 /*
 261                  * After the first rotation, all the trace data is already in
 262                  * its own chunk folder, we just need to append the suffix.
 263                  */
 264                 snprintf(new_path, PATH_MAX, "%s%s-%" PRIu64,
 265                                 session->rotation_chunk.current_rotate_path,
 266                                 datetime, session->rotate_count);
 267
 268                 fprintf(stderr, "rename %s to %s\n",
 269                                 session->rotation_chunk.current_rotate_path,
 270                                 new_path);
 271
 272                 ret = session_rename_chunk(session,
 273                                 session->rotation_chunk.current_rotate_path,
 274                                 new_path, 0);
 275                 if (ret) {
 276                         ERR("Session rename");
 277                         ret = 0;
 278                         goto error;
 279                 }
 280         }
 281
 282         /*
 283          * Store the path where the readable chunk is. This path is valid
 284          * and can be queried by the client with rotate_pending until the next
 285          * rotation is started.
 286          */
 287         snprintf(session->rotation_chunk.current_rotate_path, PATH_MAX,
 288                         "%s", new_path);
 289         session->rotate_pending = 0;
 290
 291         goto end;
 292
 293 error:
 294         session->rotate_status = LTTNG_ROTATE_ERROR;
 295 end:
 296         free(new_path);
 297         return ret;
 298 }
 299