From d7e68964d815ba9f620830ccc1680e8c8c7f57b5 Mon Sep 17 00:00:00 2001
From: Radoslaw Zarzynski <rzarzyns@redhat.com>
Date: Tue, 10 Jan 2023 14:39:31 +0000
Subject: [PATCH] test/crimson: verify the backfill cancellation & resumption

Signed-off-by: Radoslaw Zarzynski <rzarzyns@redhat.com>
---
 src/test/crimson/test_backfill.cc | 77 ++++++++++++++++++++++++++++++-
 1 file changed, 76 insertions(+), 1 deletion(-)

diff --git a/src/test/crimson/test_backfill.cc b/src/test/crimson/test_backfill.cc
index bf958cd5ae726..6648719c61c8f 100644
--- a/src/test/crimson/test_backfill.cc
+++ b/src/test/crimson/test_backfill.cc
@@ -157,7 +157,11 @@ public:
   template <class EventT>
   void next_round2() {
     ceph_assert(events_to_dispatch.size());
-    ceph_assert(typeid(*events_to_dispatch.front()) == typeid(EventT));
+    // workaround for Clang's `-Wpotentially-evaluated-expression`. See:
+    //   * https://gitlab.cern.ch/gaudi/Gaudi/-/merge_requests/970
+    //   * https://stackoverflow.com/q/46494928
+    const auto& front_event = *events_to_dispatch.front();
+    ceph_assert(typeid(front_event) == typeid(EventT));
     backfill_state.process_event(std::move(events_to_dispatch.front()));
     events_to_dispatch.pop_front();
   }
@@ -179,6 +183,15 @@ public:
 
   struct PeeringFacade;
   struct PGFacade;
+
+  void cancel() {
+    events_to_dispatch.clear();
+    schedule_event(crimson::osd::BackfillState::CancelBackfill{});
+  }
+
+  void resume() {
+    schedule_event(crimson::osd::BackfillState::Triggered{});
+  }
 };
 
 struct BackfillFixture::PeeringFacade
@@ -419,6 +432,68 @@ TEST(backfill, two_empty_replicas)
   EXPECT_TRUE(cluster_fixture.all_stores_look_like(reference_store));
 }
 
+TEST(backfill, cancel_resume)
+{
+  const auto reference_store = FakeStore{ {
+    { "1:00058bcc:::rbd_data.1018ac3e755.00000000000000d5:head", {10, 234} },
+    { "1:00ed7f8e:::rbd_data.1018ac3e755.00000000000000af:head", {10, 196} },
+    { "1:01483aea:::rbd_data.1018ac3e755.0000000000000095:head", {10, 169} },
+  }};
+  auto cluster_fixture = BackfillFixtureBuilder::add_source(
+    reference_store.objs
+  ).add_target(
+    { /* nothing 1 */ }
+  ).add_target(
+    { /* nothing 2 */ }
+  ).get_result();
+
+  EXPECT_CALL(cluster_fixture, backfilled);
+  cluster_fixture.next_round2<crimson::osd::BackfillState::PrimaryScanned>();
+  cluster_fixture.cancel();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::CancelBackfill>();
+  cluster_fixture.resume();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::Triggered>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ReplicaScanned>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ReplicaScanned>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ObjectPushed>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ObjectPushed>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ObjectPushed>();
+  cluster_fixture.next_till_done();
+
+  EXPECT_TRUE(cluster_fixture.all_stores_look_like(reference_store));
+}
+
+TEST(backfill, cancel_resume_middle_of_scan)
+{
+  const auto reference_store = FakeStore{ {
+    { "1:00058bcc:::rbd_data.1018ac3e755.00000000000000d5:head", {10, 234} },
+    { "1:00ed7f8e:::rbd_data.1018ac3e755.00000000000000af:head", {10, 196} },
+    { "1:01483aea:::rbd_data.1018ac3e755.0000000000000095:head", {10, 169} },
+  }};
+  auto cluster_fixture = BackfillFixtureBuilder::add_source(
+    reference_store.objs
+  ).add_target(
+    { /* nothing 1 */ }
+  ).add_target(
+    { /* nothing 2 */ }
+  ).get_result();
+
+  EXPECT_CALL(cluster_fixture, backfilled);
+  cluster_fixture.next_round2<crimson::osd::BackfillState::PrimaryScanned>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ReplicaScanned>();
+  cluster_fixture.cancel();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::CancelBackfill>();
+  cluster_fixture.resume();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::Triggered>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ReplicaScanned>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ObjectPushed>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ObjectPushed>();
+  cluster_fixture.next_round2<crimson::osd::BackfillState::ObjectPushed>();
+  cluster_fixture.next_till_done();
+
+  EXPECT_TRUE(cluster_fixture.all_stores_look_like(reference_store));
+}
+
 namespace StoreRandomizer {
   // FIXME: copied & pasted from test/test_snap_mapper.cc. We need to
   // find a way to avoid code duplication in test. A static library?
-- 
2.39.5