tracing::tracing local instance is dereferenced from a
cql_server::connection::process_request(), therefore tracing::tracing
service may be stop()ed only after a CQL server service is down.
On the other hand it may not be stopped before RPC service is down
because a remote side may request a tracing for a specific command too.
This patch splits the tracing::tracing stop() into two phases:
1) Flush all pending tracing records and stop the backend.
2) Stop the service.
The first phase is called after CQL server is down and before RPC is down.
The second phase is called after RPC is down.
Fixes#1339
Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Message-Id: <1465840496-19990-1-git-send-email-vladz@cloudius-systems.com>