From c569a3771369e3a53dfc88c4f7ee1ad7c8dcdd55 Mon Sep 17 00:00:00 2001
From: Brooks <brooks@solana.com>
Date: Tue, 30 May 2023 17:42:33 -0400
Subject: [PATCH] Handle errors when sending an accounts package during
 shutdown (#31874)

---
 core/tests/snapshots.rs                    |  8 +++++++-
 runtime/src/accounts_background_service.rs | 18 +++++++++++++++---
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/core/tests/snapshots.rs b/core/tests/snapshots.rs
index c72d84b35..a4fc9776f 100644
--- a/core/tests/snapshots.rs
+++ b/core/tests/snapshots.rs
@@ -233,7 +233,12 @@ fn run_bank_forks_snapshot_n<F>(
         if slot % set_root_interval == 0 || slot == last_slot {
             // set_root should send a snapshot request
             bank_forks.set_root(bank.slot(), &request_sender, None);
-            snapshot_request_handler.handle_snapshot_requests(false, 0, &mut None);
+            snapshot_request_handler.handle_snapshot_requests(
+                false,
+                0,
+                &mut None,
+                &AtomicBool::new(false),
+            );
         }
     }
 
@@ -753,6 +758,7 @@ fn test_bank_forks_incremental_snapshot(
                 false,
                 0,
                 &mut last_full_snapshot_slot,
+                &AtomicBool::new(false),
             );
         }
 
diff --git a/runtime/src/accounts_background_service.rs b/runtime/src/accounts_background_service.rs
index f650f84ea..4068e2ff3 100644
--- a/runtime/src/accounts_background_service.rs
+++ b/runtime/src/accounts_background_service.rs
@@ -149,6 +149,7 @@ impl SnapshotRequestHandler {
         test_hash_calculation: bool,
         non_snapshot_time_us: u128,
         last_full_snapshot_slot: &mut Option<Slot>,
+        exit: &AtomicBool,
     ) -> Option<Result<u64, SnapshotError>> {
         let (
             snapshot_request,
@@ -174,6 +175,7 @@ impl SnapshotRequestHandler {
             last_full_snapshot_slot,
             snapshot_request,
             accounts_package_type,
+            exit,
         ))
     }
 
@@ -295,6 +297,7 @@ impl SnapshotRequestHandler {
         last_full_snapshot_slot: &mut Option<Slot>,
         snapshot_request: SnapshotRequest,
         accounts_package_type: AccountsPackageType,
+        exit: &AtomicBool,
     ) -> Result<u64, SnapshotError> {
         debug!(
             "handling snapshot request: {:?}, {:?}",
@@ -414,9 +417,15 @@ impl SnapshotRequestHandler {
                 )
             }
         };
-        self.accounts_package_sender
-            .send(accounts_package)
-            .expect("send accounts package");
+        let send_result = self.accounts_package_sender.send(accounts_package);
+        if let Err(err) = send_result {
+            // Sending the accounts package should never fail *unless* we're shutting down.
+            let accounts_package = &err.0;
+            assert!(
+                exit.load(Ordering::Relaxed),
+                "Failed to send accounts package: {err}, {accounts_package:?}"
+            );
+        }
         snapshot_time.stop();
         info!(
             "Took bank snapshot. accounts package type: {:?}, slot: {}, bank hash: {}",
@@ -528,11 +537,13 @@ impl AbsRequestHandlers {
         test_hash_calculation: bool,
         non_snapshot_time_us: u128,
         last_full_snapshot_slot: &mut Option<Slot>,
+        exit: &AtomicBool,
     ) -> Option<Result<u64, SnapshotError>> {
         self.snapshot_request_handler.handle_snapshot_requests(
             test_hash_calculation,
             non_snapshot_time_us,
             last_full_snapshot_slot,
+            exit,
         )
     }
 }
@@ -615,6 +626,7 @@ impl AccountsBackgroundService {
                                 test_hash_calculation,
                                 non_snapshot_time,
                                 &mut last_full_snapshot_slot,
+                                &exit,
                             )
                         })
                         .flatten();