Add additional trace logging during mount (#937)

* Add additional trace logging during mount

Signed-off-by: Daniel Carl Jones <djonesoa@amazon.com>

* Remove old block used to gate SSE behind compile-time flag

Signed-off-by: Daniel Carl Jones <djonesoa@amazon.com>

---------

Signed-off-by: Daniel Carl Jones <djonesoa@amazon.com>

mountpoint-s3/src/cli.rs

@@ -476,10 +476,12 @@ where
 
                 match session {
                     Ok(session) => {
+                        tracing::trace!("FUSE session created OK, sending message back to parent process");
                         pipe_file
                             .write(&status_success)
                             .context("Failed to write data to the pipe")?;
                         drop(pipe_file);
+                        tracing::trace!("message sent back to parent process");
 
                         // Logging is set up and the mount succeeded, so we can hang up
                         // stdin/out/err now to cleanly daemonize ourselves
@@ -490,9 +492,11 @@ where
                         session.join().context("failed to join session")?;
                     }
                     Err(e) => {
+                        tracing::trace!("FUSE session creation failed, sending message back to parent process");
                         pipe_file
                             .write(&status_failure)
                             .context("Failed to write data to the pipe")?;
+                        tracing::trace!("message sent back to parent process");
                         return Err(anyhow!(e));
                     }
                 }
@@ -653,9 +657,7 @@ where
     tracing::debug!("{:?}", args);
 
     validate_mount_point(&args.mount_point)?;
-    {
-        validate_sse_args(args.sse.as_deref(), args.sse_kms_key_id.as_deref())?;
-    }
+    validate_sse_args(args.sse.as_deref(), args.sse_kms_key_id.as_deref())?;
 
     let (client, runtime, s3_personality) = client_builder(&args)?;
 
@@ -717,6 +719,7 @@ where
         }
         metadata_cache_ttl = TimeToLive::Minimal;
     }
+    tracing::trace!("using metadata TTL setting {metadata_cache_ttl:?}");
     filesystem_config.cache_config = CacheConfig::new(metadata_cache_ttl);
 
     if let Some(path) = args.cache {
@@ -780,7 +783,9 @@ where
     Client: ObjectClient + Send + Sync + 'static,
     Prefetcher: Prefetch + Send + Sync + 'static,
 {
+    tracing::trace!(?filesystem_config, "creating file system");
     let fs = S3FuseFilesystem::new(client, prefetcher, bucket_name, prefix, filesystem_config);
+    tracing::debug!(?fuse_session_config, "creating fuse session");
     let session = Session::new(fs, &fuse_session_config.mount_point, &fuse_session_config.options)
         .context("Failed to create FUSE session")?;
     let session = FuseSession::new(session, fuse_session_config.max_threads).context("Failed to start FUSE session")?;

mountpoint-s3/src/fuse/session.rs

@@ -29,6 +29,11 @@ impl FuseSession {
     ) -> anyhow::Result<Self> {
         assert!(max_worker_threads > 0);
 
+        tracing::trace!(
+            max_worker_threads,
+            "creating worker thread pool for handling FUSE requests",
+        );
+
         let unmounter = session.unmount_callable();
 
         let (tx, rx) = mpsc::channel();
@@ -37,10 +42,14 @@ impl FuseSession {
 
         // A thread that waits for all workers to exit and then sends a message on the channel
         let _waiter = {
+            const FUSE_WORKER_WAITER_THREAD_NAME: &str = "fuse-worker-waiter";
             let tx = tx.clone();
             thread::Builder::new()
-                .name("fuse-worker-waiter".to_owned())
+                .name(FUSE_WORKER_WAITER_THREAD_NAME.to_owned())
                 .spawn(move || {
+                    tracing::trace!(
+                        "{FUSE_WORKER_WAITER_THREAD_NAME} thread now waiting for all worker threads to exit",
+                    );
                     while let Ok(thd) = workers_rx.recv() {
                         let thread_name = thd.thread().name().map(ToOwned::to_owned);
                         match thd.join() {
@@ -137,6 +146,8 @@ impl<W: Work> WorkerPool<W> {
     fn start(work: W, workers: Sender<JoinHandle<W::Result>>, max_workers: usize) -> anyhow::Result<()> {
         assert!(max_workers > 0);
 
+        tracing::trace!(max_workers, "worker pool starting");
+
         let state = WorkerPoolState {
             work,
             worker_count: AtomicUsize::new(0),
@@ -150,6 +161,8 @@ impl<W: Work> WorkerPool<W> {
         if !pool.try_add_worker()? {
             unreachable!("should always create at least 1 worker (max_workers > 0)");
         }
+
+        tracing::trace!("worker pool started OK");
         Ok(())
     }