+ PERROR("Getting sub-buffer snapshot.");
+ }
+
+ return ret;
+}
+
+/*
+ * Sample consumed and produced positions for a specific fd.
+ *
+ * Returns 0 on success, < 0 on error.
+ */
+int lttng_kconsumer_sample_snapshot_positions(
+ struct lttng_consumer_stream *stream)
+{
+ assert(stream);
+
+ return kernctl_snapshot_sample_positions(stream->wait_fd);
+}
+
+/*
+ * Get the produced position
+ *
+ * Returns 0 on success, < 0 on error
+ */
+int lttng_kconsumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
+ unsigned long *pos)
+{
+ int ret;
+ int infd = stream->wait_fd;
+
+ ret = kernctl_snapshot_get_produced(infd, pos);
+ if (ret != 0) {
+ PERROR("kernctl_snapshot_get_produced");
+ }
+
+ return ret;
+}
+
+/*
+ * Get the consumerd position
+ *
+ * Returns 0 on success, < 0 on error
+ */
+int lttng_kconsumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
+ unsigned long *pos)
+{
+ int ret;
+ int infd = stream->wait_fd;
+
+ ret = kernctl_snapshot_get_consumed(infd, pos);
+ if (ret != 0) {
+ PERROR("kernctl_snapshot_get_consumed");
+ }
+
+ return ret;
+}
+
+/*
+ * Take a snapshot of all the stream of a channel
+ *
+ * Returns 0 on success, < 0 on error
+ */
+int lttng_kconsumer_snapshot_channel(uint64_t key, char *path,
+ uint64_t relayd_id, uint64_t nb_packets_per_stream,
+ struct lttng_consumer_local_data *ctx)
+{
+ int ret;
+ struct lttng_consumer_channel *channel;
+ struct lttng_consumer_stream *stream;
+
+ DBG("Kernel consumer snapshot channel %" PRIu64, key);
+
+ rcu_read_lock();
+
+ channel = consumer_find_channel(key);
+ if (!channel) {
+ ERR("No channel found for key %" PRIu64, key);
+ ret = -1;
+ goto end;
+ }
+
+ /* Splice is not supported yet for channel snapshot. */
+ if (channel->output != CONSUMER_CHANNEL_MMAP) {
+ ERR("Unsupported output %d", channel->output);
+ ret = -1;
+ goto end;
+ }
+
+ cds_list_for_each_entry(stream, &channel->streams.head, send_node) {
+ /* Are we at a position _before_ the first available packet ? */
+ bool before_first_packet = true;
+ unsigned long consumed_pos, produced_pos;
+
+ health_code_update();
+
+ /*
+ * Lock stream because we are about to change its state.
+ */
+ pthread_mutex_lock(&stream->lock);
+
+ /*
+ * Assign the received relayd ID so we can use it for streaming. The streams
+ * are not visible to anyone so this is OK to change it.
+ */
+ stream->net_seq_idx = relayd_id;
+ channel->relayd_id = relayd_id;
+ if (relayd_id != (uint64_t) -1ULL) {
+ ret = consumer_send_relayd_stream(stream, path);
+ if (ret < 0) {
+ ERR("sending stream to relayd");
+ goto end_unlock;
+ }
+ } else {
+ ret = utils_create_stream_file(path, stream->name,
+ stream->chan->tracefile_size,
+ stream->tracefile_count_current,
+ stream->uid, stream->gid, NULL);
+ if (ret < 0) {
+ ERR("utils_create_stream_file");
+ goto end_unlock;
+ }
+
+ stream->out_fd = ret;
+ stream->tracefile_size_current = 0;
+
+ DBG("Kernel consumer snapshot stream %s/%s (%" PRIu64 ")",
+ path, stream->name, stream->key);
+ }
+ if (relayd_id != -1ULL) {
+ ret = consumer_send_relayd_streams_sent(relayd_id);
+ if (ret < 0) {
+ ERR("sending streams sent to relayd");
+ goto end_unlock;
+ }
+ channel->streams_sent_to_relayd = true;
+ }
+
+ ret = kernctl_buffer_flush_empty(stream->wait_fd);
+ if (ret < 0) {
+ /*
+ * Doing a buffer flush which does not take into
+ * account empty packets. This is not perfect
+ * for stream intersection, but required as a
+ * fall-back when "flush_empty" is not
+ * implemented by lttng-modules.
+ */
+ ret = kernctl_buffer_flush(stream->wait_fd);
+ if (ret < 0) {
+ ERR("Failed to flush kernel stream");
+ goto end_unlock;
+ }
+ goto end_unlock;
+ }
+
+ ret = lttng_kconsumer_take_snapshot(stream);
+ if (ret < 0) {
+ ERR("Taking kernel snapshot");
+ goto end_unlock;
+ }
+
+ ret = lttng_kconsumer_get_produced_snapshot(stream, &produced_pos);
+ if (ret < 0) {
+ ERR("Produced kernel snapshot position");
+ goto end_unlock;
+ }
+
+ ret = lttng_kconsumer_get_consumed_snapshot(stream, &consumed_pos);
+ if (ret < 0) {
+ ERR("Consumerd kernel snapshot position");
+ goto end_unlock;
+ }
+
+ if (stream->max_sb_size == 0) {
+ ret = kernctl_get_max_subbuf_size(stream->wait_fd,
+ &stream->max_sb_size);
+ if (ret < 0) {
+ ERR("Getting kernel max_sb_size");
+ goto end_unlock;
+ }
+ }
+
+ consumed_pos = consumer_get_consume_start_pos(consumed_pos,
+ produced_pos, nb_packets_per_stream,
+ stream->max_sb_size);
+
+ while (consumed_pos < produced_pos) {
+ ssize_t read_len;
+ unsigned long len, padded_len;
+ int lost_packet = 0;
+
+ health_code_update();
+
+ DBG("Kernel consumer taking snapshot at pos %lu", consumed_pos);
+
+ ret = kernctl_get_subbuf(stream->wait_fd, &consumed_pos);
+ if (ret < 0) {
+ if (ret != -EAGAIN) {
+ PERROR("kernctl_get_subbuf snapshot");
+ goto end_unlock;
+ }
+ DBG("Kernel consumer get subbuf failed. Skipping it.");
+ consumed_pos += stream->max_sb_size;
+
+ /*
+ * Start accounting lost packets only when we
+ * already have extracted packets (to match the
+ * content of the final snapshot).
+ */
+ if (!before_first_packet) {
+ lost_packet = 1;
+ }
+ continue;
+ }
+
+ ret = kernctl_get_subbuf_size(stream->wait_fd, &len);
+ if (ret < 0) {
+ ERR("Snapshot kernctl_get_subbuf_size");
+ goto error_put_subbuf;
+ }
+
+ ret = kernctl_get_padded_subbuf_size(stream->wait_fd, &padded_len);
+ if (ret < 0) {
+ ERR("Snapshot kernctl_get_padded_subbuf_size");
+ goto error_put_subbuf;
+ }
+
+ read_len = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len,
+ padded_len - len, NULL);
+ /*
+ * We write the padded len in local tracefiles but the data len
+ * when using a relay. Display the error but continue processing
+ * to try to release the subbuffer.
+ */
+ if (relayd_id != (uint64_t) -1ULL) {
+ if (read_len != len) {
+ ERR("Error sending to the relay (ret: %zd != len: %lu)",
+ read_len, len);
+ }
+ } else {
+ if (read_len != padded_len) {
+ ERR("Error writing to tracefile (ret: %zd != len: %lu)",
+ read_len, padded_len);
+ }
+ }
+
+ ret = kernctl_put_subbuf(stream->wait_fd);
+ if (ret < 0) {
+ ERR("Snapshot kernctl_put_subbuf");
+ goto end_unlock;
+ }
+ consumed_pos += stream->max_sb_size;
+
+ /*
+ * Only account lost packets located between
+ * succesfully extracted packets (do not account before
+ * and after since they are not visible in the
+ * resulting snapshot).
+ */
+ stream->chan->lost_packets += lost_packet;
+ lost_packet = 0;
+ before_first_packet = false;
+ }
+
+ if (relayd_id == (uint64_t) -1ULL) {
+ if (stream->out_fd >= 0) {
+ ret = close(stream->out_fd);
+ if (ret < 0) {
+ PERROR("Kernel consumer snapshot close out_fd");
+ goto end_unlock;
+ }
+ stream->out_fd = -1;
+ }
+ } else {
+ close_relayd_stream(stream);
+ stream->net_seq_idx = (uint64_t) -1ULL;
+ }
+ pthread_mutex_unlock(&stream->lock);
+ }
+
+ /* All good! */
+ ret = 0;
+ goto end;
+
+error_put_subbuf:
+ ret = kernctl_put_subbuf(stream->wait_fd);
+ if (ret < 0) {
+ ERR("Snapshot kernctl_put_subbuf error path");
+ }
+end_unlock:
+ pthread_mutex_unlock(&stream->lock);
+end:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Read the whole metadata available for a snapshot.
+ *
+ * Returns 0 on success, < 0 on error
+ */
+int lttng_kconsumer_snapshot_metadata(uint64_t key, char *path,
+ uint64_t relayd_id, struct lttng_consumer_local_data *ctx)
+{
+ int ret, use_relayd = 0;
+ ssize_t ret_read;
+ struct lttng_consumer_channel *metadata_channel;
+ struct lttng_consumer_stream *metadata_stream;
+
+ assert(ctx);
+
+ DBG("Kernel consumer snapshot metadata with key %" PRIu64 " at path %s",
+ key, path);
+
+ rcu_read_lock();
+
+ metadata_channel = consumer_find_channel(key);
+ if (!metadata_channel) {
+ ERR("Kernel snapshot metadata not found for key %" PRIu64, key);
+ ret = -1;
+ goto error;
+ }
+
+ metadata_stream = metadata_channel->metadata_stream;
+ assert(metadata_stream);
+
+ /* Flag once that we have a valid relayd for the stream. */
+ if (relayd_id != (uint64_t) -1ULL) {
+ use_relayd = 1;
+ }
+
+ if (use_relayd) {
+ ret = consumer_send_relayd_stream(metadata_stream, path);
+ if (ret < 0) {
+ goto error;
+ }
+ } else {
+ ret = utils_create_stream_file(path, metadata_stream->name,
+ metadata_stream->chan->tracefile_size,
+ metadata_stream->tracefile_count_current,
+ metadata_stream->uid, metadata_stream->gid, NULL);
+ if (ret < 0) {
+ goto error;
+ }
+ metadata_stream->out_fd = ret;
+ }
+
+ do {
+ health_code_update();
+
+ ret_read = lttng_kconsumer_read_subbuffer(metadata_stream, ctx);
+ if (ret_read < 0) {
+ if (ret_read != -EAGAIN) {
+ ERR("Kernel snapshot reading metadata subbuffer (ret: %zd)",
+ ret_read);
+ goto error;
+ }
+ /* ret_read is negative at this point so we will exit the loop. */
+ continue;
+ }
+ } while (ret_read >= 0);
+
+ if (use_relayd) {
+ close_relayd_stream(metadata_stream);
+ metadata_stream->net_seq_idx = (uint64_t) -1ULL;
+ } else {
+ if (metadata_stream->out_fd >= 0) {
+ ret = close(metadata_stream->out_fd);
+ if (ret < 0) {
+ PERROR("Kernel consumer snapshot metadata close out_fd");
+ /*
+ * Don't go on error here since the snapshot was successful at this
+ * point but somehow the close failed.
+ */
+ }
+ metadata_stream->out_fd = -1;
+ }
+ }
+
+ ret = 0;
+
+ cds_list_del(&metadata_stream->send_node);
+ consumer_stream_destroy(metadata_stream, NULL);
+ metadata_channel->metadata_stream = NULL;
+error:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Receive command from session daemon and process it.
+ *
+ * Return 1 on success else a negative value or 0.
+ */
+int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
+ int sock, struct pollfd *consumer_sockpoll)
+{
+ ssize_t ret;
+ enum lttcomm_return_code ret_code = LTTCOMM_CONSUMERD_SUCCESS;
+ struct lttcomm_consumer_msg msg;
+
+ health_code_update();
+
+ ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg));
+ if (ret != sizeof(msg)) {
+ if (ret > 0) {
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_CMD);
+ ret = -1;
+ }
+ return ret;
+ }
+
+ health_code_update();
+
+ /* Deprecated command */
+ assert(msg.cmd_type != LTTNG_CONSUMER_STOP);
+
+ health_code_update();
+
+ /* relayd needs RCU read-side protection */
+ rcu_read_lock();
+
+ switch (msg.cmd_type) {
+ case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
+ {
+ /* Session daemon status message are handled in the following call. */
+ ret = consumer_add_relayd_socket(msg.u.relayd_sock.net_index,
+ msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll,
+ &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id,
+ msg.u.relayd_sock.relayd_session_id);
+ goto end_nosignal;
+ }
+ case LTTNG_CONSUMER_ADD_CHANNEL:
+ {
+ struct lttng_consumer_channel *new_channel;
+ int ret_recv;
+
+ health_code_update();
+
+ /* First send a status message before receiving the fds. */
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto error_fatal;
+ }
+
+ health_code_update();
+
+ DBG("consumer_add_channel %" PRIu64, msg.u.channel.channel_key);
+ new_channel = consumer_allocate_channel(msg.u.channel.channel_key,
+ msg.u.channel.session_id, msg.u.channel.pathname,
+ msg.u.channel.name, msg.u.channel.uid, msg.u.channel.gid,
+ msg.u.channel.relayd_id, msg.u.channel.output,
+ msg.u.channel.tracefile_size,
+ msg.u.channel.tracefile_count, 0,
+ msg.u.channel.monitor,
+ msg.u.channel.live_timer_interval,
+ NULL, NULL);
+ if (new_channel == NULL) {
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
+ goto end_nosignal;
+ }
+ new_channel->nb_init_stream_left = msg.u.channel.nb_init_streams;
+ switch (msg.u.channel.output) {
+ case LTTNG_EVENT_SPLICE:
+ new_channel->output = CONSUMER_CHANNEL_SPLICE;
+ break;
+ case LTTNG_EVENT_MMAP:
+ new_channel->output = CONSUMER_CHANNEL_MMAP;
+ break;
+ default:
+ ERR("Channel output unknown %d", msg.u.channel.output);
+ goto end_nosignal;
+ }
+
+ /* Translate and save channel type. */
+ switch (msg.u.channel.type) {
+ case CONSUMER_CHANNEL_TYPE_DATA:
+ case CONSUMER_CHANNEL_TYPE_METADATA:
+ new_channel->type = msg.u.channel.type;
+ break;
+ default:
+ assert(0);
+ goto end_nosignal;
+ };
+
+ health_code_update();
+
+ if (ctx->on_recv_channel != NULL) {
+ ret_recv = ctx->on_recv_channel(new_channel);
+ if (ret_recv == 0) {
+ ret = consumer_add_channel(new_channel, ctx);
+ } else if (ret_recv < 0) {
+ goto end_nosignal;
+ }
+ } else {
+ ret = consumer_add_channel(new_channel, ctx);
+ }
+ if (msg.u.channel.type == CONSUMER_CHANNEL_TYPE_DATA && !ret) {
+ int monitor_start_ret;
+
+ DBG("Consumer starting monitor timer");
+ consumer_timer_live_start(new_channel,
+ msg.u.channel.live_timer_interval);
+ monitor_start_ret = consumer_timer_monitor_start(
+ new_channel,
+ msg.u.channel.monitor_timer_interval);
+ if (monitor_start_ret < 0) {
+ ERR("Starting channel monitoring timer failed");
+ goto end_nosignal;
+ }
+
+ }
+
+ health_code_update();
+
+ /* If we received an error in add_channel, we need to report it. */
+ if (ret < 0) {
+ ret = consumer_send_status_msg(sock, ret);
+ if (ret < 0) {
+ goto error_fatal;
+ }
+ goto end_nosignal;
+ }
+
+ goto end_nosignal;
+ }
+ case LTTNG_CONSUMER_ADD_STREAM:
+ {
+ int fd;
+ struct lttng_pipe *stream_pipe;
+ struct lttng_consumer_stream *new_stream;
+ struct lttng_consumer_channel *channel;
+ int alloc_ret = 0;
+
+ /*
+ * Get stream's channel reference. Needed when adding the stream to the
+ * global hash table.
+ */
+ channel = consumer_find_channel(msg.u.stream.channel_key);
+ if (!channel) {
+ /*
+ * We could not find the channel. Can happen if cpu hotplug
+ * happens while tearing down.
+ */
+ ERR("Unable to find channel key %" PRIu64, msg.u.stream.channel_key);
+ ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
+ }
+
+ health_code_update();
+
+ /* First send a status message before receiving the fds. */
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto error_fatal;
+ }
+
+ health_code_update();
+
+ if (ret_code != LTTCOMM_CONSUMERD_SUCCESS) {
+ /* Channel was not found. */
+ goto end_nosignal;
+ }
+
+ /* Blocking call */
+ health_poll_entry();
+ ret = lttng_consumer_poll_socket(consumer_sockpoll);
+ health_poll_exit();
+ if (ret) {
+ goto error_fatal;
+ }
+
+ health_code_update();
+
+ /* Get stream file descriptor from socket */
+ ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
+ if (ret != sizeof(fd)) {
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD);
+ rcu_read_unlock();
+ return ret;
+ }
+
+ health_code_update();
+
+ /*
+ * Send status code to session daemon only if the recv works. If the
+ * above recv() failed, the session daemon is notified through the
+ * error socket and the teardown is eventually done.
+ */
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto end_nosignal;
+ }
+
+ health_code_update();
+
+ new_stream = consumer_allocate_stream(channel->key,
+ fd,
+ LTTNG_CONSUMER_ACTIVE_STREAM,
+ channel->name,
+ channel->uid,
+ channel->gid,
+ channel->relayd_id,
+ channel->session_id,
+ msg.u.stream.cpu,
+ &alloc_ret,
+ channel->type,
+ channel->monitor);
+ if (new_stream == NULL) {
+ switch (alloc_ret) {
+ case -ENOMEM:
+ case -EINVAL:
+ default:
+ lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
+ break;
+ }
+ goto end_nosignal;
+ }
+
+ new_stream->chan = channel;
+ new_stream->wait_fd = fd;
+ switch (channel->output) {
+ case CONSUMER_CHANNEL_SPLICE:
+ new_stream->output = LTTNG_EVENT_SPLICE;
+ ret = utils_create_pipe(new_stream->splice_pipe);
+ if (ret < 0) {
+ goto end_nosignal;
+ }
+ break;
+ case CONSUMER_CHANNEL_MMAP:
+ new_stream->output = LTTNG_EVENT_MMAP;
+ break;
+ default:
+ ERR("Stream output unknown %d", channel->output);
+ goto end_nosignal;
+ }
+
+ /*
+ * We've just assigned the channel to the stream so increment the
+ * refcount right now. We don't need to increment the refcount for
+ * streams in no monitor because we handle manually the cleanup of
+ * those. It is very important to make sure there is NO prior
+ * consumer_del_stream() calls or else the refcount will be unbalanced.
+ */
+ if (channel->monitor) {
+ uatomic_inc(&new_stream->chan->refcount);
+ }
+
+ /*
+ * The buffer flush is done on the session daemon side for the kernel
+ * so no need for the stream "hangup_flush_done" variable to be
+ * tracked. This is important for a kernel stream since we don't rely
+ * on the flush state of the stream to read data. It's not the case for
+ * user space tracing.
+ */
+ new_stream->hangup_flush_done = 0;
+
+ health_code_update();
+
+ if (ctx->on_recv_stream) {
+ ret = ctx->on_recv_stream(new_stream);
+ if (ret < 0) {
+ consumer_stream_free(new_stream);
+ goto end_nosignal;
+ }
+ }
+
+ health_code_update();
+
+ if (new_stream->metadata_flag) {
+ channel->metadata_stream = new_stream;
+ }
+
+ /* Do not monitor this stream. */
+ if (!channel->monitor) {
+ DBG("Kernel consumer add stream %s in no monitor mode with "
+ "relayd id %" PRIu64, new_stream->name,
+ new_stream->net_seq_idx);
+ cds_list_add(&new_stream->send_node, &channel->streams.head);
+ break;
+ }
+
+ /* Send stream to relayd if the stream has an ID. */
+ if (new_stream->net_seq_idx != (uint64_t) -1ULL) {
+ ret = consumer_send_relayd_stream(new_stream,
+ new_stream->chan->pathname);
+ if (ret < 0) {
+ consumer_stream_free(new_stream);
+ goto end_nosignal;
+ }
+
+ /*
+ * If adding an extra stream to an already
+ * existing channel (e.g. cpu hotplug), we need
+ * to send the "streams_sent" command to relayd.
+ */
+ if (channel->streams_sent_to_relayd) {
+ ret = consumer_send_relayd_streams_sent(
+ new_stream->net_seq_idx);
+ if (ret < 0) {
+ goto end_nosignal;
+ }
+ }
+ }
+
+ /* Get the right pipe where the stream will be sent. */
+ if (new_stream->metadata_flag) {
+ ret = consumer_add_metadata_stream(new_stream);
+ if (ret) {
+ ERR("Consumer add metadata stream %" PRIu64 " failed. Continuing",
+ new_stream->key);
+ consumer_stream_free(new_stream);
+ goto end_nosignal;
+ }
+ stream_pipe = ctx->consumer_metadata_pipe;
+ } else {
+ ret = consumer_add_data_stream(new_stream);
+ if (ret) {
+ ERR("Consumer add stream %" PRIu64 " failed. Continuing",
+ new_stream->key);
+ consumer_stream_free(new_stream);
+ goto end_nosignal;
+ }
+ stream_pipe = ctx->consumer_data_pipe;
+ }
+
+ /* Vitible to other threads */
+ new_stream->globally_visible = 1;
+
+ health_code_update();
+
+ ret = lttng_pipe_write(stream_pipe, &new_stream, sizeof(new_stream));
+ if (ret < 0) {
+ ERR("Consumer write %s stream to pipe %d",
+ new_stream->metadata_flag ? "metadata" : "data",
+ lttng_pipe_get_writefd(stream_pipe));
+ if (new_stream->metadata_flag) {
+ consumer_del_stream_for_metadata(new_stream);
+ } else {
+ consumer_del_stream_for_data(new_stream);
+ }
+ goto end_nosignal;
+ }
+
+ DBG("Kernel consumer ADD_STREAM %s (fd: %d) with relayd id %" PRIu64,
+ new_stream->name, fd, new_stream->relayd_stream_id);
+ break;
+ }
+ case LTTNG_CONSUMER_STREAMS_SENT:
+ {
+ struct lttng_consumer_channel *channel;
+
+ /*
+ * Get stream's channel reference. Needed when adding the stream to the
+ * global hash table.
+ */
+ channel = consumer_find_channel(msg.u.sent_streams.channel_key);
+ if (!channel) {
+ /*
+ * We could not find the channel. Can happen if cpu hotplug
+ * happens while tearing down.
+ */
+ ERR("Unable to find channel key %" PRIu64,
+ msg.u.sent_streams.channel_key);
+ ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
+ }
+
+ health_code_update();
+
+ /*
+ * Send status code to session daemon.
+ */
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0 || ret_code != LTTCOMM_CONSUMERD_SUCCESS) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto end_nosignal;
+ }
+
+ health_code_update();
+
+ /*
+ * We should not send this message if we don't monitor the
+ * streams in this channel.
+ */
+ if (!channel->monitor) {
+ break;
+ }
+
+ health_code_update();
+ /* Send stream to relayd if the stream has an ID. */
+ if (msg.u.sent_streams.net_seq_idx != (uint64_t) -1ULL) {
+ ret = consumer_send_relayd_streams_sent(
+ msg.u.sent_streams.net_seq_idx);
+ if (ret < 0) {
+ goto end_nosignal;
+ }
+ channel->streams_sent_to_relayd = true;
+ }
+ break;
+ }
+ case LTTNG_CONSUMER_UPDATE_STREAM:
+ {
+ rcu_read_unlock();
+ return -ENOSYS;
+ }
+ case LTTNG_CONSUMER_DESTROY_RELAYD:
+ {
+ uint64_t index = msg.u.destroy_relayd.net_seq_idx;
+ struct consumer_relayd_sock_pair *relayd;
+
+ DBG("Kernel consumer destroying relayd %" PRIu64, index);
+
+ /* Get relayd reference if exists. */
+ relayd = consumer_find_relayd(index);
+ if (relayd == NULL) {
+ DBG("Unable to find relayd %" PRIu64, index);
+ ret_code = LTTCOMM_CONSUMERD_RELAYD_FAIL;
+ }
+
+ /*
+ * Each relayd socket pair has a refcount of stream attached to it
+ * which tells if the relayd is still active or not depending on the
+ * refcount value.
+ *
+ * This will set the destroy flag of the relayd object and destroy it
+ * if the refcount reaches zero when called.
+ *
+ * The destroy can happen either here or when a stream fd hangs up.
+ */
+ if (relayd) {
+ consumer_flag_relayd_for_destroy(relayd);
+ }
+
+ health_code_update();
+
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto error_fatal;
+ }
+
+ goto end_nosignal;
+ }
+ case LTTNG_CONSUMER_DATA_PENDING:
+ {
+ int32_t ret;
+ uint64_t id = msg.u.data_pending.session_id;
+
+ DBG("Kernel consumer data pending command for id %" PRIu64, id);
+
+ ret = consumer_data_pending(id);
+
+ health_code_update();
+
+ /* Send back returned value to session daemon */
+ ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret));
+ if (ret < 0) {
+ PERROR("send data pending ret code");
+ goto error_fatal;
+ }
+
+ /*
+ * No need to send back a status message since the data pending
+ * returned value is the response.
+ */
+ break;
+ }
+ case LTTNG_CONSUMER_SNAPSHOT_CHANNEL:
+ {
+ if (msg.u.snapshot_channel.metadata == 1) {
+ ret = lttng_kconsumer_snapshot_metadata(msg.u.snapshot_channel.key,
+ msg.u.snapshot_channel.pathname,
+ msg.u.snapshot_channel.relayd_id, ctx);
+ if (ret < 0) {
+ ERR("Snapshot metadata failed");
+ ret_code = LTTCOMM_CONSUMERD_ERROR_METADATA;
+ }
+ } else {
+ ret = lttng_kconsumer_snapshot_channel(msg.u.snapshot_channel.key,
+ msg.u.snapshot_channel.pathname,
+ msg.u.snapshot_channel.relayd_id,
+ msg.u.snapshot_channel.nb_packets_per_stream,
+ ctx);
+ if (ret < 0) {
+ ERR("Snapshot channel failed");
+ ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
+ }
+ }
+
+ health_code_update();
+
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto end_nosignal;
+ }
+ break;
+ }
+ case LTTNG_CONSUMER_DESTROY_CHANNEL:
+ {
+ uint64_t key = msg.u.destroy_channel.key;
+ struct lttng_consumer_channel *channel;
+
+ channel = consumer_find_channel(key);
+ if (!channel) {
+ ERR("Kernel consumer destroy channel %" PRIu64 " not found", key);
+ ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
+ }
+
+ health_code_update();
+
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto end_nosignal;
+ }
+
+ health_code_update();
+
+ /* Stop right now if no channel was found. */
+ if (!channel) {
+ goto end_nosignal;
+ }
+
+ /*
+ * This command should ONLY be issued for channel with streams set in
+ * no monitor mode.
+ */
+ assert(!channel->monitor);
+
+ /*
+ * The refcount should ALWAYS be 0 in the case of a channel in no
+ * monitor mode.
+ */
+ assert(!uatomic_sub_return(&channel->refcount, 1));
+
+ consumer_del_channel(channel);
+
+ goto end_nosignal;
+ }
+ case LTTNG_CONSUMER_DISCARDED_EVENTS:
+ {
+ uint64_t ret;
+ struct lttng_consumer_channel *channel;
+ uint64_t id = msg.u.discarded_events.session_id;
+ uint64_t key = msg.u.discarded_events.channel_key;
+
+ DBG("Kernel consumer discarded events command for session id %"
+ PRIu64 ", channel key %" PRIu64, id, key);
+
+ channel = consumer_find_channel(key);
+ if (!channel) {
+ ERR("Kernel consumer discarded events channel %"
+ PRIu64 " not found", key);
+ ret = 0;
+ } else {
+ ret = channel->discarded_events;
+ }
+
+ health_code_update();
+
+ /* Send back returned value to session daemon */
+ ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret));
+ if (ret < 0) {
+ PERROR("send discarded events");
+ goto error_fatal;
+ }
+
+ break;
+ }
+ case LTTNG_CONSUMER_LOST_PACKETS:
+ {
+ uint64_t ret;
+ struct lttng_consumer_channel *channel;
+ uint64_t id = msg.u.lost_packets.session_id;
+ uint64_t key = msg.u.lost_packets.channel_key;
+
+ DBG("Kernel consumer lost packets command for session id %"
+ PRIu64 ", channel key %" PRIu64, id, key);
+
+ channel = consumer_find_channel(key);
+ if (!channel) {
+ ERR("Kernel consumer lost packets channel %"
+ PRIu64 " not found", key);
+ ret = 0;
+ } else {
+ ret = channel->lost_packets;
+ }
+
+ health_code_update();
+
+ /* Send back returned value to session daemon */
+ ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret));
+ if (ret < 0) {
+ PERROR("send lost packets");
+ goto error_fatal;
+ }
+
+ break;
+ }
+ case LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE:
+ {
+ int channel_monitor_pipe;
+
+ ret_code = LTTCOMM_CONSUMERD_SUCCESS;
+ /* Successfully received the command's type. */
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ goto error_fatal;
+ }
+
+ ret = lttcomm_recv_fds_unix_sock(sock, &channel_monitor_pipe,
+ 1);
+ if (ret != sizeof(channel_monitor_pipe)) {
+ ERR("Failed to receive channel monitor pipe");
+ goto error_fatal;
+ }
+
+ DBG("Received channel monitor pipe (%d)", channel_monitor_pipe);
+ ret = consumer_timer_thread_set_channel_monitor_pipe(
+ channel_monitor_pipe);
+ if (!ret) {
+ int flags;
+
+ ret_code = LTTCOMM_CONSUMERD_SUCCESS;
+ /* Set the pipe as non-blocking. */
+ ret = fcntl(channel_monitor_pipe, F_GETFL, 0);
+ if (ret == -1) {
+ PERROR("fcntl get flags of the channel monitoring pipe");
+ goto error_fatal;
+ }
+ flags = ret;
+
+ ret = fcntl(channel_monitor_pipe, F_SETFL,
+ flags | O_NONBLOCK);
+ if (ret == -1) {
+ PERROR("fcntl set O_NONBLOCK flag of the channel monitoring pipe");
+ goto error_fatal;
+ }
+ DBG("Channel monitor pipe set as non-blocking");
+ } else {
+ ret_code = LTTCOMM_CONSUMERD_ALREADY_SET;
+ }
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ goto error_fatal;
+ }
+ break;
+ }
+ default:
+ goto end_nosignal;