return ret;
}
+/*
+ * Send a clear quiescent command to consumer using the given channel key.
+ *
+ * Return 0 on success else a negative value.
+ */
+int consumer_clear_quiescent_channel(struct consumer_socket *socket, uint64_t key)
+{
+ int ret;
+ struct lttcomm_consumer_msg msg;
+
+ assert(socket);
+
+ DBG2("Consumer clear quiescent channel key %" PRIu64, key);
+
+ memset(&msg, 0, sizeof(msg));
+ msg.cmd_type = LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL;
+ msg.u.clear_quiescent_channel.key = key;
+
+ pthread_mutex_lock(socket->lock);
+ health_code_update();
+
+ ret = consumer_send_msg(socket, &msg);
+ if (ret < 0) {
+ goto end;
+ }
+
+end:
+ health_code_update();
+ pthread_mutex_unlock(socket->lock);
+ return ret;
+}
+
/*
* Send a close metadata command to consumer using the given channel key.
* Called with registry lock held.
uint64_t metadata_key, char *metadata_str, size_t len,
size_t target_offset);
int consumer_flush_channel(struct consumer_socket *socket, uint64_t key);
+int consumer_clear_quiescent_channel(struct consumer_socket *socket, uint64_t key);
/* Snapshot command. */
int consumer_snapshot_channel(struct consumer_socket *socket, uint64_t key,
return ret;
}
+static
+int ust_app_clear_quiescent_app_session(struct ust_app *app,
+ struct ust_app_session *ua_sess)
+{
+ int ret = 0;
+ struct lttng_ht_iter iter;
+ struct ust_app_channel *ua_chan;
+ struct consumer_socket *socket;
+
+ DBG("Clearing stream quiescent state for ust app pid %d", app->pid);
+
+ rcu_read_lock();
+
+ if (!app->compatible) {
+ goto end_not_compatible;
+ }
+
+ pthread_mutex_lock(&ua_sess->lock);
+
+ if (ua_sess->deleted) {
+ goto end_unlock;
+ }
+
+ health_code_update();
+
+ socket = consumer_find_socket_by_bitness(app->bits_per_long,
+ ua_sess->consumer);
+ if (!socket) {
+ ERR("Failed to find consumer (%" PRIu32 ") socket",
+ app->bits_per_long);
+ ret = -1;
+ goto end_unlock;
+ }
+
+ /* Clear quiescent state. */
+ switch (ua_sess->buffer_type) {
+ case LTTNG_BUFFER_PER_PID:
+ cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter,
+ ua_chan, node.node) {
+ health_code_update();
+ ret = consumer_clear_quiescent_channel(socket,
+ ua_chan->key);
+ if (ret) {
+ ERR("Error clearing quiescent state for consumer channel");
+ ret = -1;
+ continue;
+ }
+ }
+ break;
+ case LTTNG_BUFFER_PER_UID:
+ default:
+ assert(0);
+ ret = -1;
+ break;
+ }
+
+ health_code_update();
+
+end_unlock:
+ pthread_mutex_unlock(&ua_sess->lock);
+
+end_not_compatible:
+ rcu_read_unlock();
+ health_code_update();
+ return ret;
+}
+
+/*
+ * Clear quiescent state in each stream for all applications for a
+ * specific UST session.
+ * Called with UST session lock held.
+ */
+static
+int ust_app_clear_quiescent_session(struct ltt_ust_session *usess)
+
+{
+ int ret = 0;
+
+ DBG("Clearing stream quiescent state for all ust apps");
+
+ rcu_read_lock();
+
+ switch (usess->buffer_type) {
+ case LTTNG_BUFFER_PER_UID:
+ {
+ struct lttng_ht_iter iter;
+ struct buffer_reg_uid *reg;
+
+ /*
+ * Clear quiescent for all per UID buffers associated to
+ * that session.
+ */
+ cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
+ struct consumer_socket *socket;
+ struct buffer_reg_channel *reg_chan;
+
+ /* Get associated consumer socket.*/
+ socket = consumer_find_socket_by_bitness(
+ reg->bits_per_long, usess->consumer);
+ if (!socket) {
+ /*
+ * Ignore request if no consumer is found for
+ * the session.
+ */
+ continue;
+ }
+
+ cds_lfht_for_each_entry(reg->registry->channels->ht,
+ &iter.iter, reg_chan, node.node) {
+ /*
+ * The following call will print error values so
+ * the return code is of little importance
+ * because whatever happens, we have to try them
+ * all.
+ */
+ (void) consumer_clear_quiescent_channel(socket,
+ reg_chan->consumer_key);
+ }
+ }
+ break;
+ }
+ case LTTNG_BUFFER_PER_PID:
+ {
+ struct ust_app_session *ua_sess;
+ struct lttng_ht_iter iter;
+ struct ust_app *app;
+
+ cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app,
+ pid_n.node) {
+ ua_sess = lookup_session_by_app(usess, app);
+ if (ua_sess == NULL) {
+ continue;
+ }
+ (void) ust_app_clear_quiescent_app_session(app,
+ ua_sess);
+ }
+ break;
+ }
+ default:
+ ret = -1;
+ assert(0);
+ break;
+ }
+
+ rcu_read_unlock();
+ health_code_update();
+ return ret;
+}
+
/*
* Destroy a specific UST session in apps.
*/
rcu_read_lock();
+ /*
+ * In a start-stop-start use-case, we need to clear the quiescent state
+ * of each channel set by the prior stop command, thus ensuring that a
+ * following stop or destroy is sure to grab a timestamp_end near those
+ * operations, even if the packet is empty.
+ */
+ (void) ust_app_clear_quiescent_session(usess);
+
cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
ret = ust_app_start_trace(usess, app);
if (ret < 0) {
LTTNG_CONSUMER_SNAPSHOT_CHANNEL,
LTTNG_CONSUMER_SNAPSHOT_METADATA,
LTTNG_CONSUMER_STREAMS_SENT,
+ LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL,
};
/* State of each fd in consumer */
int data_read;
int hangup_flush_done;
+ /*
+ * Whether the stream is in a "complete" state (e.g. it does not have a
+ * partially written sub-buffer.
+ *
+ * Initialized to "false" on stream creation (first packet is empty).
+ *
+ * The various transitions of the quiescent state are:
+ * - On "start" tracing: set to false, since the stream is not
+ * "complete".
+ * - On "stop" tracing: if !quiescent -> flush FINAL (update
+ * timestamp_end), and set to true; the stream has entered a
+ * complete/quiescent state.
+ * - On "destroy" or stream/application hang-up: if !quiescent ->
+ * flush FINAL, and set to true.
+ *
+ * NOTE: Update and read are protected by the stream lock.
+ */
+ bool quiescent;
+
/*
* metadata_timer_lock protects flags waiting_on_metadata and
* missed_metadata_flush.
struct {
uint64_t key; /* Channel key. */
} LTTNG_PACKED flush_channel;
+ struct {
+ uint64_t key; /* Channel key. */
+ } LTTNG_PACKED clear_quiescent_channel;
struct {
char pathname[PATH_MAX];
/* Indicate if the snapshot goes on the relayd or locally. */
health_code_update();
- ustctl_flush_buffer(stream->ustream, 1);
+ pthread_mutex_lock(&stream->lock);
+ if (!stream->quiescent) {
+ ustctl_flush_buffer(stream->ustream, 0);
+ stream->quiescent = true;
+ }
+ pthread_mutex_unlock(&stream->lock);
+ }
+error:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Clear quiescent state from channel's streams using the given key to
+ * retrieve the channel.
+ *
+ * Return 0 on success else an LTTng error code.
+ */
+static int clear_quiescent_channel(uint64_t chan_key)
+{
+ int ret = 0;
+ struct lttng_consumer_channel *channel;
+ struct lttng_consumer_stream *stream;
+ struct lttng_ht *ht;
+ struct lttng_ht_iter iter;
+
+ DBG("UST consumer clear quiescent channel key %" PRIu64, chan_key);
+
+ rcu_read_lock();
+ channel = consumer_find_channel(chan_key);
+ if (!channel) {
+ ERR("UST consumer clear quiescent channel %" PRIu64 " not found", chan_key);
+ ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
+ goto error;
+ }
+
+ ht = consumer_data.stream_per_chan_id_ht;
+
+ /* For each stream of the channel id, clear quiescent state. */
+ cds_lfht_for_each_entry_duplicate(ht->ht,
+ ht->hash_fct(&channel->key, lttng_ht_seed), ht->match_fct,
+ &channel->key, &iter.iter, stream, node_channel_id.node) {
+
+ health_code_update();
+
+ pthread_mutex_lock(&stream->lock);
+ stream->quiescent = false;
+ pthread_mutex_unlock(&stream->lock);
}
error:
rcu_read_unlock();
goto end_msg_sessiond;
}
+ case LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL:
+ {
+ int ret;
+
+ ret = clear_quiescent_channel(
+ msg.u.clear_quiescent_channel.key);
+ if (ret != 0) {
+ ret_code = ret;
+ }
+
+ goto end_msg_sessiond;
+ }
case LTTNG_CONSUMER_PUSH_METADATA:
{
int ret;
}
/*
- * Called when the stream signal the consumer that it has hang up.
+ * Called when the stream signals the consumer that it has hung up.
*/
void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream *stream)
{
assert(stream);
assert(stream->ustream);
- ustctl_flush_buffer(stream->ustream, 0);
+ pthread_mutex_lock(&stream->lock);
+ if (!stream->quiescent) {
+ ustctl_flush_buffer(stream->ustream, 0);
+ stream->quiescent = true;
+ }
+ pthread_mutex_unlock(&stream->lock);
stream->hangup_flush_done = 1;
}
projects / lttng-tools.git / commitdiff
