static int send_stream_to_thread(struct lttng_consumer_stream *stream,
struct lttng_consumer_local_data *ctx)
{
- int ret, stream_pipe;
+ int ret;
+ struct lttng_pipe *stream_pipe;
/* Get the right pipe where the stream will be sent. */
if (stream->metadata_flag) {
- stream_pipe = ctx->consumer_metadata_pipe[1];
+ stream_pipe = ctx->consumer_metadata_pipe;
} else {
- stream_pipe = ctx->consumer_data_pipe[1];
+ stream_pipe = ctx->consumer_data_pipe;
}
- do {
- ret = write(stream_pipe, &stream, sizeof(stream));
- } while (ret < 0 && errno == EINTR);
+ ret = lttng_pipe_write(stream_pipe, &stream, sizeof(stream));
if (ret < 0) {
- PERROR("Consumer write %s stream to pipe %d",
- stream->metadata_flag ? "metadata" : "data", stream_pipe);
+ ERR("Consumer write %s stream to pipe %d",
+ stream->metadata_flag ? "metadata" : "data",
+ lttng_pipe_get_writefd(stream_pipe));
}
return ret;
*/
stream->wait_fd = wait_fd;
+ /*
+ * Increment channel refcount since the channel reference has now been
+ * assigned in the allocation process above.
+ */
+ uatomic_inc(&stream->chan->refcount);
+
/*
* Order is important this is why a list is used. On error, the caller
* should clean this list.
struct lttng_consumer_channel *channel,
struct lttng_consumer_local_data *ctx, int *relayd_error)
{
- int ret;
+ int ret, ret_code = LTTNG_OK;
struct lttng_consumer_stream *stream;
assert(channel);
DBG("UST consumer sending channel %s to sessiond", channel->name);
- /* Send channel to sessiond. */
- ret = ustctl_send_channel_to_sessiond(sock, channel->uchan);
- if (ret < 0) {
- goto error;
- }
-
- ret = ustctl_channel_close_wakeup_fd(channel->uchan);
- if (ret < 0) {
- goto error;
- }
-
- /* The channel was sent successfully to the sessiond at this point. */
cds_list_for_each_entry(stream, &channel->streams.head, send_node) {
/* Try to send the stream to the relayd if one is available. */
ret = send_stream_to_relayd(stream);
if (relayd_error) {
*relayd_error = 1;
}
- goto error;
+ ret_code = LTTNG_ERR_RELAYD_CONNECT_FAIL;
}
+ }
+
+ /* Inform sessiond that we are about to send channel and streams. */
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0 || ret_code != LTTNG_OK) {
+ /*
+ * Either the session daemon is not responding or the relayd died so we
+ * stop now.
+ */
+ goto error;
+ }
+ /* Send channel to sessiond. */
+ ret = ustctl_send_channel_to_sessiond(sock, channel->uchan);
+ if (ret < 0) {
+ goto error;
+ }
+
+ ret = ustctl_channel_close_wakeup_fd(channel->uchan);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /* The channel was sent successfully to the sessiond at this point. */
+ cds_list_for_each_entry(stream, &channel->streams.head, send_node) {
/* Send stream to session daemon. */
ret = send_sessiond_stream(sock, stream);
if (ret < 0) {
return 0;
error:
+ if (ret_code != LTTNG_OK) {
+ ret = -1;
+ }
return ret;
}
channel->wait_fd = ustctl_channel_get_wait_fd(channel->uchan);
- if (ret < 0) {
- goto error;
- }
-
/* Open all streams for this channel. */
ret = create_ust_streams(channel, ctx);
if (ret < 0) {
DBG("UST consumer writing metadata to channel %s", metadata->name);
+ if (!metadata->metadata_stream) {
+ ret = 0;
+ goto error;
+ }
+
assert(target_offset <= metadata->metadata_cache->max_offset);
ret = ustctl_write_metadata_to_channel(metadata->uchan,
metadata_str + target_offset, len);
channel = consumer_find_channel(chan_key);
if (!channel) {
- ERR("UST consumer close metadata %" PRIu64 " not found", chan_key);
+ /*
+ * This is possible if the metadata thread has issue a delete because
+ * the endpoint point of the stream hung up. There is no way the
+ * session daemon can know about it thus use a DBG instead of an actual
+ * error.
+ */
+ DBG("UST consumer close metadata %" PRIu64 " not found", chan_key);
ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
goto error;
}
pthread_mutex_lock(&consumer_data.lock);
- if (!cds_lfht_is_node_deleted(&channel->node.node)) {
- if (channel->switch_timer_enabled == 1) {
- DBG("Deleting timer on metadata channel");
- consumer_timer_switch_stop(channel);
- }
+
+ if (cds_lfht_is_node_deleted(&channel->node.node)) {
+ goto error_unlock;
+ }
+
+ if (channel->switch_timer_enabled == 1) {
+ DBG("Deleting timer on metadata channel");
+ consumer_timer_switch_stop(channel);
+ }
+
+ if (channel->metadata_stream) {
ret = ustctl_stream_close_wakeup_fd(channel->metadata_stream->ustream);
if (ret < 0) {
ERR("UST consumer unable to close fd of metadata (ret: %d)", ret);
if (!metadata) {
ERR("UST consumer push metadata %" PRIu64 " not found", key);
ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
- goto error;
+ goto error_find;
}
/*
/* List MUST be empty after or else it could be reused. */
assert(cds_list_empty(&metadata->streams.head));
- ret = 0;
+ return 0;
error:
+ /*
+ * Delete metadata channel on error. At this point, the metadata stream can
+ * NOT be monitored by the metadata thread thus having the guarantee that
+ * the stream is still in the local stream list of the channel. This call
+ * will make sure to clean that list.
+ */
+ consumer_del_channel(metadata);
+error_find:
return ret;
}
goto end_free;
}
+ /*
+ * XXX: The consumer data lock is acquired before calling metadata cache
+ * write which calls push metadata that MUST be protected by the consumer
+ * lock in order to be able to check the validity of the metadata stream of
+ * the channel.
+ *
+ * Note that this will be subject to change to better fine grained locking
+ * and ultimately try to get rid of this global consumer data lock.
+ */
+ pthread_mutex_lock(&consumer_data.lock);
+
pthread_mutex_lock(&channel->metadata_cache->lock);
ret = consumer_metadata_cache_write(channel, offset, len, metadata_str);
if (ret < 0) {
/* Unable to handle metadata. Notify session daemon. */
ret_code = LTTCOMM_CONSUMERD_ERROR_METADATA;
+ /*
+ * Skip metadata flush on write error since the offset and len might
+ * not have been updated which could create an infinite loop below when
+ * waiting for the metadata cache to be flushed.
+ */
+ pthread_mutex_unlock(&channel->metadata_cache->lock);
+ pthread_mutex_unlock(&consumer_data.lock);
+ goto end_free;
}
pthread_mutex_unlock(&channel->metadata_cache->lock);
+ pthread_mutex_unlock(&consumer_data.lock);
while (consumer_metadata_cache_flushed(channel, offset + len)) {
DBG("Waiting for metadata to be flushed");
* The ret value might 0 meaning an orderly shutdown but this is ok
* since the caller handles this.
*/
+ if (ret > 0) {
+ ret = -1;
+ }
return ret;
}
if (msg.cmd_type == LTTNG_CONSUMER_STOP) {
sizeof(is_data_pending));
if (ret < 0) {
DBG("Error when sending the data pending ret code: %d", ret);
+ goto error_fatal;
}
/*
ret = consumer_send_status_channel(sock, channel);
if (ret < 0) {
/*
- * There is probably a problem on the socket so the poll will get
- * it and clean everything up.
+ * There is probably a problem on the socket.
*/
- goto end_nosignal;
+ goto error_fatal;
}
break;
goto end_msg_sessiond;
}
- /* Inform sessiond that we are about to send channel and streams. */
- ret = consumer_send_status_msg(sock, LTTNG_OK);
- if (ret < 0) {
- /* Somehow, the session daemon is not responding anymore. */
- goto end_nosignal;
- }
-
/* Send everything to sessiond. */
ret = send_sessiond_channel(sock, channel, ctx, &relayd_err);
if (ret < 0) {
/*
* We were unable to send to the relayd the stream so avoid
* sending back a fatal error to the thread since this is OK
- * and the consumer can continue its work.
+ * and the consumer can continue its work. The above call
+ * has sent the error status message to the sessiond.
*/
- ret_code = LTTNG_ERR_RELAYD_CONNECT_FAIL;
- goto end_msg_sessiond;
+ goto end_nosignal;
}
/*
* The communicaton was broken hence there is a bad state between
/* Wait for more data. */
if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
- goto end_nosignal;
+ goto error_fatal;
}
ret = lttng_ustconsumer_recv_metadata(sock, key, offset,
len, channel);
if (ret < 0) {
/* error receiving from sessiond */
- goto end_nosignal;
+ goto error_fatal;
} else {
ret_code = ret;
goto end_msg_sessiond;
}
goto end_msg_sessiond;
}
+ case LTTNG_CONSUMER_SNAPSHOT_CHANNEL:
+ {
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ /* Somehow, the session daemon is not responding anymore. */
+ goto end_nosignal;
+ }
+ break;
+ }
default:
break;
}
* the caller because the session daemon socket management is done
* elsewhere. Returning a negative code or 0 will shutdown the consumer.
*/
- (void) consumer_send_status_msg(sock, ret_code);
+ ret = consumer_send_status_msg(sock, ret_code);
+ if (ret < 0) {
+ goto error_fatal;
+ }
rcu_read_unlock();
return 1;
end_channel_error:
ret_code = lttng_ustconsumer_recv_metadata(ctx->consumer_metadata_socket,
key, offset, len, channel);
- (void) consumer_send_status_msg(ctx->consumer_metadata_socket, ret_code);
+ if (ret_code >= 0) {
+ /*
+ * Only send the status msg if the sessiond is alive meaning a positive
+ * ret code.
+ */
+ (void) consumer_send_status_msg(ctx->consumer_metadata_socket, ret_code);
+ }
ret = 0;
end: