| 1 | /* |
| 2 | * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation; either version 2 |
| 7 | * of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 17 | */ |
| 18 | |
| 19 | #define _GNU_SOURCE |
| 20 | #include <errno.h> |
| 21 | #include <stdlib.h> |
| 22 | #include <stdio.h> |
| 23 | #include <string.h> |
| 24 | #include <unistd.h> |
| 25 | |
| 26 | #include "lttngerr.h" |
| 27 | #include "ltt-sessiond.h" |
| 28 | #include "libkernelctl.h" |
| 29 | #include "kernel-ctl.h" |
| 30 | #include "trace.h" |
| 31 | |
| 32 | /* |
| 33 | * kernel_create_session |
| 34 | * |
| 35 | * Create a new kernel session using the command context session. |
| 36 | */ |
| 37 | int kernel_create_session(struct ltt_session *session, int tracer_fd) |
| 38 | { |
| 39 | int ret; |
| 40 | struct ltt_kernel_session *lks; |
| 41 | |
| 42 | /* Allocate a new kernel session */ |
| 43 | lks = malloc(sizeof(struct ltt_kernel_session)); |
| 44 | if (lks == NULL) { |
| 45 | perror("kernel session malloc"); |
| 46 | ret = -errno; |
| 47 | goto error; |
| 48 | } |
| 49 | |
| 50 | ret = kernctl_create_session(tracer_fd); |
| 51 | if (ret < 0) { |
| 52 | goto error; |
| 53 | } |
| 54 | |
| 55 | /* Assigning session fd and to the command context */ |
| 56 | lks->fd = ret; |
| 57 | lks->channel_count = 0; |
| 58 | lks->stream_count_global = 0; |
| 59 | session->kernel_session = lks; |
| 60 | session->kern_session_count++; |
| 61 | CDS_INIT_LIST_HEAD(&lks->channel_list.head); |
| 62 | |
| 63 | DBG("Kernel session created (fd: %d)", lks->fd); |
| 64 | |
| 65 | return 0; |
| 66 | |
| 67 | error: |
| 68 | return ret; |
| 69 | } |
| 70 | |
| 71 | /* |
| 72 | * kernel_create_channel |
| 73 | * |
| 74 | * Create a kernel channel within the kernel session. |
| 75 | */ |
| 76 | int kernel_create_channel(struct ltt_kernel_session *session) |
| 77 | { |
| 78 | int ret; |
| 79 | struct ltt_kernel_channel *lkc; |
| 80 | struct lttng_kernel_channel *chan; |
| 81 | |
| 82 | lkc = malloc(sizeof(struct ltt_kernel_channel)); |
| 83 | chan = malloc(sizeof(struct lttng_kernel_channel)); |
| 84 | |
| 85 | if (lkc == NULL || chan == NULL) { |
| 86 | perror("kernel channel malloc"); |
| 87 | ret = -errno; |
| 88 | goto error; |
| 89 | } |
| 90 | |
| 91 | chan->overwrite = DEFAULT_KERNEL_OVERWRITE; |
| 92 | chan->subbuf_size = DEFAULT_KERNEL_SUBBUF_SIZE; |
| 93 | chan->num_subbuf = DEFAULT_KERNEL_SUBBUF_NUM; |
| 94 | chan->switch_timer_interval = DEFAULT_KERNEL_SWITCH_TIMER; |
| 95 | chan->read_timer_interval = DEFAULT_KERNEL_READ_TIMER; |
| 96 | |
| 97 | ret = kernctl_create_channel(session->fd, chan); |
| 98 | if (ret < 0) { |
| 99 | perror("ioctl create channel"); |
| 100 | goto error; |
| 101 | } |
| 102 | |
| 103 | /* Setup the channel */ |
| 104 | lkc->fd = ret; |
| 105 | lkc->channel = chan; |
| 106 | lkc->stream_count = 0; |
| 107 | ret = asprintf(&lkc->pathname, "%s", DEFAULT_TRACE_OUTPUT); |
| 108 | if (ret < 0) { |
| 109 | perror("asprintf kernel create channel"); |
| 110 | goto error; |
| 111 | } |
| 112 | |
| 113 | DBG("Channel path set to %s", lkc->pathname); |
| 114 | |
| 115 | CDS_INIT_LIST_HEAD(&lkc->events_list.head); |
| 116 | CDS_INIT_LIST_HEAD(&lkc->stream_list.head); |
| 117 | cds_list_add(&lkc->list, &session->channel_list.head); |
| 118 | session->channel_count++; |
| 119 | |
| 120 | DBG("Kernel channel created (fd: %d)", lkc->fd); |
| 121 | |
| 122 | return 0; |
| 123 | |
| 124 | error: |
| 125 | return ret; |
| 126 | } |
| 127 | |
| 128 | /* |
| 129 | * kernel_enable_event |
| 130 | * |
| 131 | * Enable kernel event. |
| 132 | */ |
| 133 | int kernel_enable_event(struct ltt_kernel_session *session, char *name) |
| 134 | { |
| 135 | int ret; |
| 136 | struct ltt_kernel_channel *chan; |
| 137 | struct ltt_kernel_event *event; |
| 138 | struct lttng_kernel_event *lke; |
| 139 | |
| 140 | event = malloc(sizeof(struct ltt_kernel_event)); |
| 141 | lke = malloc(sizeof(struct lttng_kernel_event)); |
| 142 | |
| 143 | if (event == NULL || lke == NULL) { |
| 144 | perror("kernel enable event malloc"); |
| 145 | ret = -errno; |
| 146 | goto error; |
| 147 | } |
| 148 | |
| 149 | /* Setting up a kernel event */ |
| 150 | strncpy(lke->name, name, LTTNG_SYM_NAME_LEN); |
| 151 | lke->instrumentation = LTTNG_KERNEL_TRACEPOINTS; |
| 152 | event->event = lke; |
| 153 | |
| 154 | cds_list_for_each_entry(chan, &session->channel_list.head, list) { |
| 155 | ret = kernctl_create_event(chan->fd, lke); |
| 156 | if (ret < 0) { |
| 157 | goto error; |
| 158 | } |
| 159 | |
| 160 | event->fd = ret; |
| 161 | /* Add event to event list */ |
| 162 | cds_list_add(&event->list, &chan->events_list.head); |
| 163 | DBG("Event %s enabled (fd: %d)", name, event->fd); |
| 164 | } |
| 165 | |
| 166 | return 0; |
| 167 | |
| 168 | error: |
| 169 | return ret; |
| 170 | } |
| 171 | |
| 172 | /* |
| 173 | * kernel_open_metadata |
| 174 | * |
| 175 | * Open metadata stream. |
| 176 | */ |
| 177 | int kernel_open_metadata(struct ltt_kernel_session *session) |
| 178 | { |
| 179 | int ret; |
| 180 | struct ltt_kernel_metadata *lkm; |
| 181 | struct lttng_kernel_channel *conf; |
| 182 | |
| 183 | lkm = malloc(sizeof(struct ltt_kernel_metadata)); |
| 184 | conf = malloc(sizeof(struct lttng_kernel_channel)); |
| 185 | |
| 186 | if (lkm == NULL || conf == NULL) { |
| 187 | perror("kernel open metadata malloc"); |
| 188 | ret = -errno; |
| 189 | goto error; |
| 190 | } |
| 191 | |
| 192 | conf->overwrite = DEFAULT_KERNEL_OVERWRITE; |
| 193 | conf->subbuf_size = DEFAULT_KERNEL_SUBBUF_SIZE; |
| 194 | conf->num_subbuf = DEFAULT_KERNEL_SUBBUF_NUM; |
| 195 | conf->switch_timer_interval = DEFAULT_KERNEL_SWITCH_TIMER; |
| 196 | conf->read_timer_interval = DEFAULT_KERNEL_READ_TIMER; |
| 197 | |
| 198 | ret = kernctl_open_metadata(session->fd, conf); |
| 199 | if (ret < 0) { |
| 200 | goto error; |
| 201 | } |
| 202 | |
| 203 | lkm->fd = ret; |
| 204 | lkm->conf = conf; |
| 205 | ret = asprintf(&lkm->pathname, "%s/metadata", DEFAULT_TRACE_OUTPUT); |
| 206 | if (ret < 0) { |
| 207 | perror("asprintf kernel metadata"); |
| 208 | goto error; |
| 209 | } |
| 210 | session->metadata = lkm; |
| 211 | |
| 212 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
| 213 | |
| 214 | return 0; |
| 215 | |
| 216 | error: |
| 217 | return ret; |
| 218 | } |
| 219 | |
| 220 | /* |
| 221 | * kernel_start_session |
| 222 | * |
| 223 | * Start tracing session. |
| 224 | */ |
| 225 | int kernel_start_session(struct ltt_kernel_session *session) |
| 226 | { |
| 227 | int ret; |
| 228 | |
| 229 | ret = kernctl_start_session(session->fd); |
| 230 | if (ret < 0) { |
| 231 | goto error; |
| 232 | } |
| 233 | |
| 234 | DBG("Kernel session started"); |
| 235 | |
| 236 | return 0; |
| 237 | |
| 238 | error: |
| 239 | return ret; |
| 240 | } |
| 241 | |
| 242 | /* |
| 243 | * kernel_stop_session |
| 244 | * |
| 245 | * Stop tracing session. |
| 246 | */ |
| 247 | int kernel_stop_session(struct ltt_kernel_session *session) |
| 248 | { |
| 249 | int ret; |
| 250 | |
| 251 | ret = kernctl_stop_session(session->fd); |
| 252 | if (ret < 0) { |
| 253 | goto error; |
| 254 | } |
| 255 | |
| 256 | DBG("Kernel session stopped"); |
| 257 | |
| 258 | return 0; |
| 259 | |
| 260 | error: |
| 261 | return ret; |
| 262 | } |
| 263 | |
| 264 | /* |
| 265 | * kernel_create_channel_stream |
| 266 | * |
| 267 | * Create a stream for a channel. |
| 268 | * |
| 269 | * Return the number of created stream. Else, a negative value. |
| 270 | */ |
| 271 | int kernel_create_channel_stream(struct ltt_kernel_channel *channel) |
| 272 | { |
| 273 | int ret; |
| 274 | struct ltt_kernel_stream *lks; |
| 275 | |
| 276 | while ((ret = kernctl_create_stream(channel->fd)) > 0) { |
| 277 | lks = malloc(sizeof(struct ltt_kernel_stream)); |
| 278 | if (lks == NULL) { |
| 279 | perror("kernel create stream malloc"); |
| 280 | ret = -errno; |
| 281 | goto error; |
| 282 | } |
| 283 | |
| 284 | lks->fd = ret; |
| 285 | ret = asprintf(&lks->pathname, "%s/trace_%d", |
| 286 | channel->pathname, channel->stream_count); |
| 287 | if (ret < 0) { |
| 288 | perror("asprintf kernel create stream"); |
| 289 | goto error; |
| 290 | } |
| 291 | lks->state = 0; |
| 292 | |
| 293 | cds_list_add(&lks->list, &channel->stream_list.head); |
| 294 | channel->stream_count++; |
| 295 | } |
| 296 | |
| 297 | DBG("Kernel channel stream created (num: %d)", channel->stream_count); |
| 298 | |
| 299 | return channel->stream_count; |
| 300 | |
| 301 | error: |
| 302 | return ret; |
| 303 | } |
| 304 | |
| 305 | /* |
| 306 | * kernel_create_metadata_stream |
| 307 | * |
| 308 | * Create the metadata stream. |
| 309 | */ |
| 310 | int kernel_create_metadata_stream(struct ltt_kernel_session *session) |
| 311 | { |
| 312 | int ret; |
| 313 | |
| 314 | ret = kernctl_create_stream(session->metadata->fd); |
| 315 | if (ret < 0) { |
| 316 | perror("kernel create metadata stream"); |
| 317 | ret = -errno; |
| 318 | goto error; |
| 319 | } |
| 320 | |
| 321 | DBG("Kernel metadata stream created (fd: %d)", ret); |
| 322 | session->metadata_stream_fd = ret; |
| 323 | |
| 324 | return 0; |
| 325 | |
| 326 | error: |
| 327 | return ret; |
| 328 | } |