distributed-loader: Remove ensure_system_table_directories

It looks like the exactly same code is called few steps above via

distributed_loader::init_system_keyspace
 `- distributed_loader::populate_keyspace

While at it -- move the supervisor::notify("loading system sstables")
handing around in the more suitable location.

tests: https://jenkins.scylladb.com/job/releng/job/Scylla-CI/981/

Signed-off-by: Pavel Emelyanov <[email protected]>
Message-Id: <[email protected]>

Author: Pavel Emelyanov' via ScyllaDB development

main.cc

@@ -960,6 +960,7 @@ To start the scylla server proper, simply invoke as: scylla server (or just scyl
             // Iteration through column family directory for sstable loading is
             // done only by shard 0, so we'll no longer face race conditions as
             // described here: https://github.com/scylladb/scylla/issues/1014
+            supervisor::notify("loading system sstables");
             replica::distributed_loader::init_system_keyspace(db, ss, gossiper, *cfg).get();
 
             smp::invoke_on_all([blocked_reactor_notify_ms] {
@@ -1057,10 +1058,6 @@ To start the scylla server proper, simply invoke as: scylla server (or just scyl
             // schema migration, if needed, is also done on shard 0
             db::legacy_schema_migrator::migrate(proxy, db, qp.local()).get();
 
-            supervisor::notify("loading system sstables");
-
-            replica::distributed_loader::ensure_system_table_directories(db).get();
-
             // making compaction manager api available, after system keyspace has already been established.
             api::set_server_compaction_manager(ctx).get();
 

replica/distributed_loader.cc

@@ -599,16 +599,6 @@ future<> distributed_loader::init_system_keyspace(distributed<replica::database>
     });
 }
 
-future<> distributed_loader::ensure_system_table_directories(distributed<replica::database>& db) {
-    return parallel_for_each(system_keyspaces, [&db](std::string_view ksname) {
-        auto& ks = db.local().find_keyspace(ksname);
-        return parallel_for_each(ks.metadata()->cf_meta_data(), [&ks] (auto& pair) {
-            auto cfm = pair.second;
-            return ks.make_directory_for_column_family(cfm->cf_name(), cfm->id());
-        });
-    });
-}
-
 future<> distributed_loader::init_non_system_keyspaces(distributed<replica::database>& db,
         distributed<service::storage_proxy>& proxy, sharded<db::system_keyspace>& sys_ks) {
     return seastar::async([&db, &proxy, &sys_ks] {

replica/distributed_loader.hh

@@ -79,7 +79,6 @@ class distributed_loader {
 public:
     static future<> init_system_keyspace(distributed<replica::database>& db, distributed<service::storage_service>& ss, sharded<gms::gossiper>& g, db::config& cfg);
     static future<> init_non_system_keyspaces(distributed<replica::database>& db, distributed<service::storage_proxy>& proxy, sharded<db::system_keyspace>& sys_ks);
-    static future<> ensure_system_table_directories(distributed<replica::database>& db);
 
     // Scan sstables under upload directory. Return a vector with smp::count entries.
     // Each entry with index of idx should be accessed on shard idx only.