Improve logging in stop

.. we provide finer-grained logging after each step of `stop`.

Author: tnull

src/lib.rs

@@ -147,9 +147,7 @@ use types::{
 };
 pub use types::{ChannelDetails, CustomTlvRecord, PeerDetails, UserChannelId};
 
-#[cfg(tokio_unstable)]
-use logger::log_trace;
-use logger::{log_debug, log_error, log_info, LdkLogger, Logger};
+use logger::{log_debug, log_error, log_info, log_trace, LdkLogger, Logger};
 
 use lightning::chain::BestBlock;
 use lightning::events::bump_transaction::Wallet as LdkWallet;
@@ -578,7 +576,6 @@ impl Node {
 			})
 		};
 
-		let background_stop_logger = Arc::clone(&self.logger);
 		let handle = runtime.spawn(async move {
 			process_events_async(
 				background_persister,
@@ -599,7 +596,6 @@ impl Node {
 				log_error!(background_error_logger, "Failed to process events: {}", e);
 				panic!("Failed to process events");
 			});
-			log_debug!(background_stop_logger, "Events processing stopped.",);
 		});
 		debug_assert!(self.background_processor_task.lock().unwrap().is_none());
 		*self.background_processor_task.lock().unwrap() = Some(handle);
@@ -642,7 +638,7 @@ impl Node {
 
 		// Stop background tasks.
 		match self.stop_sender.send(()) {
-			Ok(_) => (),
+			Ok(_) => log_trace!(self.logger, "Sent shutdown signal to background tasks."),
 			Err(e) => {
 				log_error!(
 					self.logger,
@@ -655,6 +651,7 @@ impl Node {
 
 		// Disconnect all peers.
 		self.peer_manager.disconnect_all_peers();
+		log_debug!(self.logger, "Disconnected all network peers.");
 
 		// Ensure we process the broadcast queue one last time, as we may have generated
 		// force-closures during peer disconnection.
@@ -663,9 +660,11 @@ impl Node {
 		tokio::task::block_in_place(move || {
 			runtime_ref.block_on(async { chain_source.try_process_broadcast_queue().await })
 		});
+		log_debug!(self.logger, "Disconnected all network peers.");
 
 		// Stop any runtime-dependant chain sources.
 		self.chain_source.stop();
+		log_debug!(self.logger, "Stopped chain sources.");
 
 		// Wait until background processing stopped, at least until a timeout is reached.
 		if let Some(background_processor_task) =
@@ -684,7 +683,7 @@ impl Node {
 
 			match timeout_res {
 				Ok(stop_res) => match stop_res {
-					Ok(()) => {},
+					Ok(()) => log_debug!(self.logger, "Stopped background processing of events."),
 					Err(e) => {
 						abort_handle.abort();
 						log_error!(