Fix: consumer: snapshot: assertion on subsequent snapshot

[lttng-tools.git] / src / common / ust-consumer / ust-consumer.cpp

diff --git a/src/common/ust-consumer/ust-consumer.cpp b/src/common/ust-consumer/ust-consumer.cpp
index 766c9d30c7ff27f1a7ff796043f24aaf2a3ad90a..b08cafdff9da6c217fb2702a7ad0e55379514de1 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.cpp
+++ b/src/common/ust-consumer/ust-consumer.cpp
@@ -49,46 +49,6 @@ extern int consumer_poll_timeout;
 
 LTTNG_EXPORT DEFINE_LTTNG_UST_SIGBUS_STATE();
 
-/*
- * Free channel object and all streams associated with it. This MUST be used
- * only and only if the channel has _NEVER_ been added to the global channel
- * hash table.
- */
-static void destroy_channel(struct lttng_consumer_channel *channel)
-{
-       struct lttng_consumer_stream *stream, *stmp;
-
-       LTTNG_ASSERT(channel);
-
-       DBG("UST consumer cleaning stream list");
-
-       cds_list_for_each_entry_safe(stream, stmp, &channel->streams.head,
-                       send_node) {
-
-               health_code_update();
-
-               cds_list_del_init(&stream->send_node);
-               lttng_ust_ctl_destroy_stream(stream->ustream);
-               lttng_trace_chunk_put(stream->trace_chunk);
-               free(stream);
-       }
-
-       /*
-        * If a channel is available meaning that was created before the streams
-        * were, delete it.
-        */
-       if (channel->uchan) {
-               lttng_ustconsumer_del_channel(channel);
-               lttng_ustconsumer_free_channel(channel);
-       }
-
-       if (channel->trace_chunk) {
-               lttng_trace_chunk_put(channel->trace_chunk);
-       }
-
-       free(channel);
-}
-
 /*
  * Add channel to internal consumer state.
  *
@@ -742,6 +702,14 @@ static int flush_channel(uint64_t chan_key)
 next:
                pthread_mutex_unlock(&stream->lock);
        }
+
+       /*
+        * Send one last buffer statistics update to the session daemon. This
+        * ensures that the session daemon gets at least one statistics update
+        * per channel even in the case of short-lived channels, such as when a
+        * short-lived app is traced in per-pid mode.
+        */
+       sample_and_send_channel_buffer_stats(channel);
 error:
        rcu_read_unlock();
        return ret;
@@ -1121,13 +1089,13 @@ static int snapshot_channel(struct lttng_consumer_channel *channel,
                if (use_relayd) {
                        ret = consumer_send_relayd_stream(stream, path);
                        if (ret < 0) {
-                               goto error_unlock;
+                               goto error_close_stream;
                        }
                } else {
                        ret = consumer_stream_create_output_files(stream,
                                        false);
                        if (ret < 0) {
-                               goto error_unlock;
+                               goto error_close_stream;
                        }
                        DBG("UST consumer snapshot stream (%" PRIu64 ")",
                                        stream->key);
@@ -1149,19 +1117,19 @@ static int snapshot_channel(struct lttng_consumer_channel *channel,
                ret = lttng_ustconsumer_take_snapshot(stream);
                if (ret < 0) {
                        ERR("Taking UST snapshot");
-                       goto error_unlock;
+                       goto error_close_stream;
                }
 
                ret = lttng_ustconsumer_get_produced_snapshot(stream, &produced_pos);
                if (ret < 0) {
                        ERR("Produced UST snapshot position");
-                       goto error_unlock;
+                       goto error_close_stream;
                }
 
                ret = lttng_ustconsumer_get_consumed_snapshot(stream, &consumed_pos);
                if (ret < 0) {
                        ERR("Consumerd UST snapshot position");
-                       goto error_unlock;
+                       goto error_close_stream;
                }
 
                /*
@@ -2133,9 +2101,11 @@ end_rotate_channel_nosignal:
        case LTTNG_CONSUMER_INIT:
        {
                int ret_send_status;
+               lttng_uuid sessiond_uuid;
 
-               ret_code = lttng_consumer_init_command(ctx,
-                               msg.u.init.sessiond_uuid);
+               std::copy(std::begin(msg.u.init.sessiond_uuid), std::end(msg.u.init.sessiond_uuid),
+                               sessiond_uuid.begin());
+               ret_code = lttng_consumer_init_command(ctx, sessiond_uuid);
                health_code_update();
                ret_send_status = consumer_send_status_msg(sock, ret_code);
                if (ret_send_status < 0) {
@@ -2315,11 +2285,7 @@ end_msg_sessiond:
 
 end_channel_error:
        if (channel) {
-               /*
-                * Free channel here since no one has a reference to it. We don't
-                * free after that because a stream can store this pointer.
-                */
-               destroy_channel(channel);
+               consumer_del_channel(channel);
        }
        /* We have to send a status channel message indicating an error. */
        {
@@ -2465,8 +2431,9 @@ void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream *stream)
                        stream->quiescent = true;
                }
        }
-       pthread_mutex_unlock(&stream->lock);
+
        stream->hangup_flush_done = 1;
+       pthread_mutex_unlock(&stream->lock);
 }
 
 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel *chan)