/*
* Push metadata to consumer socket.
*
- * The socket lock MUST be acquired.
- * The ust app session lock MUST be acquired.
+ * RCU read-side lock must be held to guarantee existance of socket.
+ * Must be called with the ust app session lock held.
+ * Must be called with the registry lock held.
*
* On success, return the len of metadata pushed or else a negative value.
*/
assert(registry);
assert(socket);
- pthread_mutex_lock(®istry->lock);
-
/*
- * Means that no metadata was assigned to the session. This can happens if
- * no start has been done previously.
+ * Means that no metadata was assigned to the session. This can
+ * happens if no start has been done previously.
*/
if (!registry->metadata_key) {
- pthread_mutex_unlock(®istry->lock);
return 0;
}
/*
- * On a push metadata error either the consumer is dead or the metadata
- * channel has been destroyed because its endpoint might have died (e.g:
- * relayd). If so, the metadata closed flag is set to 1 so we deny pushing
- * metadata again which is not valid anymore on the consumer side.
+ * On a push metadata error either the consumer is dead or the
+ * metadata channel has been destroyed because its endpoint
+ * might have died (e.g: relayd). If so, the metadata closed
+ * flag is set to 1 so we deny pushing metadata again which is
+ * not valid anymore on the consumer side.
*/
if (registry->metadata_closed) {
- pthread_mutex_unlock(®istry->lock);
return -EPIPE;
}
registry->metadata_len_sent += len;
push_data:
- pthread_mutex_unlock(®istry->lock);
ret = consumer_push_metadata(socket, registry->metadata_key,
metadata_str, len, offset);
if (ret < 0) {
/*
- * There is an acceptable race here between the registry metadata key
- * assignment and the creation on the consumer. The session daemon can
- * concurrently push metadata for this registry while being created on
- * the consumer since the metadata key of the registry is assigned
- * *before* it is setup to avoid the consumer to ask for metadata that
- * could possibly be not found in the session daemon.
+ * There is an acceptable race here between the registry
+ * metadata key assignment and the creation on the
+ * consumer. The session daemon can concurrently push
+ * metadata for this registry while being created on the
+ * consumer since the metadata key of the registry is
+ * assigned *before* it is setup to avoid the consumer
+ * to ask for metadata that could possibly be not found
+ * in the session daemon.
*
- * The metadata will get pushed either by the session being stopped or
- * the consumer requesting metadata if that race is triggered.
+ * The metadata will get pushed either by the session
+ * being stopped or the consumer requesting metadata if
+ * that race is triggered.
*/
if (ret == -LTTCOMM_CONSUMERD_CHANNEL_FAIL) {
ret = 0;
}
- /* Update back the actual metadata len sent since it failed here. */
- pthread_mutex_lock(®istry->lock);
+ /*
+ * Update back the actual metadata len sent since it
+ * failed here.
+ */
registry->metadata_len_sent -= len;
- pthread_mutex_unlock(®istry->lock);
ret_val = ret;
goto error_push;
}
error:
if (ret_val) {
/*
- * On error, flag the registry that the metadata is closed. We were unable
- * to push anything and this means that either the consumer is not
- * responding or the metadata cache has been destroyed on the consumer.
+ * On error, flag the registry that the metadata is
+ * closed. We were unable to push anything and this
+ * means that either the consumer is not responding or
+ * the metadata cache has been destroyed on the
+ * consumer.
*/
registry->metadata_closed = 1;
}
- pthread_mutex_unlock(®istry->lock);
error_push:
free(metadata_str);
return ret_val;
* socket to send the metadata is retrieved from consumer, if sock
* is not NULL we use it to send the metadata.
* RCU read-side lock must be held while calling this function,
- * therefore ensuring existance of registry.
+ * therefore ensuring existance of registry. It also ensures existance
+ * of socket throughout this function.
*
* Return 0 on success else a negative error.
*/
assert(consumer);
pthread_mutex_lock(®istry->lock);
-
if (registry->metadata_closed) {
- pthread_mutex_unlock(®istry->lock);
- return -EPIPE;
+ ret_val = -EPIPE;
+ goto error;
}
/* Get consumer socket to use to push the metadata.*/
socket = consumer_find_socket_by_bitness(registry->bits_per_long,
consumer);
- pthread_mutex_unlock(®istry->lock);
if (!socket) {
ret_val = -1;
goto error;
}
- /*
- * TODO: Currently, we hold the socket lock around sampling of the next
- * metadata segment to ensure we send metadata over the consumer socket in
- * the correct order. This makes the registry lock nest inside the socket
- * lock.
- *
- * Please note that this is a temporary measure: we should move this lock
- * back into ust_consumer_push_metadata() when the consumer gets the
- * ability to reorder the metadata it receives.
- */
- pthread_mutex_lock(socket->lock);
ret = ust_app_push_metadata(registry, socket, 0);
- pthread_mutex_unlock(socket->lock);
if (ret < 0) {
ret_val = ret;
goto error;
}
-
+ pthread_mutex_unlock(®istry->lock);
return 0;
error:
end:
+ pthread_mutex_unlock(®istry->lock);
return ret_val;
}
/*
* Send to the consumer a close metadata command for the given session. Once
* done, the metadata channel is deleted and the session metadata pointer is
- * nullified. The session lock MUST be acquired here unless the application is
+ * nullified. The session lock MUST be held unless the application is
* in the destroy path.
*
* Return 0 on success else a negative value.
assert(reg_chan);
reg_chan->consumer_key = ua_chan->key;
reg_chan->subbuf_size = ua_chan->attr.subbuf_size;
+ reg_chan->num_subbuf = ua_chan->attr.num_subbuf;
/* Create and add a channel registry to session. */
ret = ust_registry_channel_add(reg_sess->reg.ust,
int ust_app_flush_session(struct ltt_ust_session *usess)
{
- int ret;
+ int ret = 0;
DBG("Flushing session buffers for all ust apps");
/* Push metadata. */
(void) push_metadata(ust_session_reg, usess->consumer);
}
- ret = 0;
break;
}
case LTTNG_BUFFER_PER_PID:
break;
}
default:
+ ret = -1;
assert(0);
break;
}
* Return 0 on success or else a negative value.
*/
int ust_app_snapshot_record(struct ltt_ust_session *usess,
- struct snapshot_output *output, int wait, uint64_t max_stream_size)
+ struct snapshot_output *output, int wait,
+ uint64_t nb_packets_per_stream)
{
int ret = 0;
unsigned int snapshot_done = 0;
reg_chan, node.node) {
ret = consumer_snapshot_channel(socket, reg_chan->consumer_key,
output, 0, usess->uid, usess->gid, pathname, wait,
- max_stream_size);
+ nb_packets_per_stream);
if (ret < 0) {
goto error;
}
}
ret = consumer_snapshot_channel(socket,
reg->registry->reg.ust->metadata_key, output, 1,
- usess->uid, usess->gid, pathname, wait, max_stream_size);
+ usess->uid, usess->gid, pathname, wait, 0);
if (ret < 0) {
goto error;
}
ua_chan, node.node) {
ret = consumer_snapshot_channel(socket, ua_chan->key, output,
0, ua_sess->euid, ua_sess->egid, pathname, wait,
- max_stream_size);
+ nb_packets_per_stream);
if (ret < 0) {
goto error;
}
registry = get_session_registry(ua_sess);
assert(registry);
ret = consumer_snapshot_channel(socket, registry->metadata_key, output,
- 1, ua_sess->euid, ua_sess->egid, pathname, wait,
- max_stream_size);
+ 1, ua_sess->euid, ua_sess->egid, pathname, wait, 0);
if (ret < 0) {
goto error;
}
}
/*
- * Return the number of streams for a UST session.
+ * Return the size taken by one more packet per stream.
*/
-unsigned int ust_app_get_nb_stream(struct ltt_ust_session *usess)
+uint64_t ust_app_get_size_one_more_packet_per_stream(struct ltt_ust_session *usess,
+ uint64_t cur_nr_packets)
{
- unsigned int ret = 0;
+ uint64_t tot_size = 0;
struct ust_app *app;
struct lttng_ht_iter iter;
rcu_read_lock();
cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
reg_chan, node.node) {
- ret += reg_chan->stream_count;
+ if (cur_nr_packets >= reg_chan->num_subbuf) {
+ /*
+ * Don't take channel into account if we
+ * already grab all its packets.
+ */
+ continue;
+ }
+ tot_size += reg_chan->subbuf_size * reg_chan->stream_count;
}
rcu_read_unlock();
}
cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter,
ua_chan, node.node) {
- ret += ua_chan->streams.count;
+ if (cur_nr_packets >= ua_chan->attr.num_subbuf) {
+ /*
+ * Don't take channel into account if we
+ * already grab all its packets.
+ */
+ continue;
+ }
+ tot_size += ua_chan->attr.subbuf_size * ua_chan->streams.count;
}
}
rcu_read_unlock();
break;
}
- return ret;
+ return tot_size;
}
projects / lttng-tools.git / blobdiff