Minor refactoring

src/backend/distributed/connection/connection_management.c

@@ -55,8 +55,6 @@ static bool ShouldShutdownConnection(MultiConnection *connection, const int
 									 cachedConnectionCount);
 static void ResetConnection(MultiConnection *connection);
 static void DefaultCitusNoticeProcessor(void *arg, const char *message);
-static void RegisterConnectionCleanup(void);
-static void CitusCleanupConnectionsAtExit(int code, Datum arg);
 static MultiConnection * FindAvailableConnection(dlist_head *connections, uint32 flags);
 static bool RemoteTransactionIdle(MultiConnection *connection);
 static int EventSetSizeForConnectionList(List *connections);
@@ -349,42 +347,10 @@ StartNodeUserDatabaseConnection(uint32 flags, const char *hostname, int32 port,
 
 	ResetShardPlacementAssociation(connection);
 
-	RegisterConnectionCleanup();
-
 	return connection;
 }
 
 
-/*
- * RegisterConnectionCleanup cleans up any resources left at the end of the
- * session. We prefer to cleanup before shared memory exit to make sure that
- * this session properly releases anything hold in the shared memory.
- */
-static void
-RegisterConnectionCleanup(void)
-{
-	static bool registeredCleanup = false;
-	if (registeredCleanup == false)
-	{
-		before_shmem_exit(CitusCleanupConnectionsAtExit, 0);
-
-		registeredCleanup = true;
-	}
-}
-
-
-/*
- * CitusCleanupConnectionsAtExit is called before_shmem_exit() of the
- * backend for the purposes of any clean-up needed.
- */
-static void
-CitusCleanupConnectionsAtExit(int code, Datum arg)
-{
-	/* properly close all the cached connections */
-	ShutdownAllConnections();
-}
-
-
 /*
  * FindAvailableConnection searches the given list of connections for one that
  * is not claimed exclusively.

src/backend/distributed/connection/shared_connection_stats.c

@@ -48,17 +48,6 @@ typedef struct ConnectionStatsSharedData
 	char *sharedConnectionHashTrancheName;
 
 	LWLock sharedConnectionHashLock;
-
-/*	/ * */
-/*	 * We prefer mutex over LwLocks for two reasons: */
-/*	 *   - The operations we perform while holding the lock is very tiny, and */
-/*	 *     performance wise, mutex is encouraged by Postgres for such cases */
-/*	 *   - We have to acquire the lock "atexit" callback, and LwLocks requires */
-/*	 *     MyProc to be avaliable to acquire the lock. However, "atexit", it is */
-/*	 *     not guranteed to have MyProc avaliable. On the other hand, "mutex" is */
-/*	 *     independent from MyProc. */
-/*	 * / */
-/*	slock_t mutex; */
 } ConnectionStatsSharedData;
 
 typedef struct SharedConnStatsHashKey
@@ -436,8 +425,6 @@ static void
 LockConnectionSharedMemory(LWLockMode lockMode)
 {
 	LWLockAcquire(&ConnectionStatsSharedState->sharedConnectionHashLock, lockMode);
-
-	/* SpinLockAcquire(&ConnectionStatsSharedState->mutex); */
 }
 
 
@@ -449,8 +436,6 @@ static void
 UnLockConnectionSharedMemory(void)
 {
 	LWLockRelease(&ConnectionStatsSharedState->sharedConnectionHashLock);
-
-	/* SpinLockRelease(&ConnectionStatsSharedState->mutex); */
 }
 
 
@@ -535,8 +520,6 @@ SharedConnectionStatsShmemInit(void)
 
 		LWLockInitialize(&ConnectionStatsSharedState->sharedConnectionHashLock,
 						 ConnectionStatsSharedState->sharedConnectionHashTrancheId);
-
-		/* SpinLockInit(&ConnectionStatsSharedState->mutex); */
 	}
 
 	/*  allocate hash table */

src/backend/distributed/shared_library_init.c

@@ -91,6 +91,8 @@ void _PG_init(void);
 
 static void ResizeStackToMaximumDepth(void);
 static void multi_log_hook(ErrorData *edata);
+static void RegisterConnectionCleanup(void);
+static void CitusCleanupConnectionsAtExit(int code, Datum arg);
 static void CreateRequiredDirectories(void);
 static void RegisterCitusConfigVariables(void);
 static bool ErrorIfNotASuitableDeadlockFactor(double *newval, void **extra,
@@ -369,6 +371,37 @@ StartupCitusBackend(void)
 {
 	InitializeMaintenanceDaemonBackend();
 	InitializeBackendData();
+	RegisterConnectionCleanup();
+}
+
+
+/*
+ * RegisterConnectionCleanup cleans up any resources left at the end of the
+ * session. We prefer to cleanup before shared memory exit to make sure that
+ * this session properly releases anything hold in the shared memory.
+ */
+static void
+RegisterConnectionCleanup(void)
+{
+	static bool registeredCleanup = false;
+	if (registeredCleanup == false)
+	{
+		before_shmem_exit(CitusCleanupConnectionsAtExit, 0);
+
+		registeredCleanup = true;
+	}
+}
+
+
+/*
+ * CitusCleanupConnectionsAtExit is called before_shmem_exit() of the
+ * backend for the purposes of any clean-up needed.
+ */
+static void
+CitusCleanupConnectionsAtExit(int code, Datum arg)
+{
+	/* properly close all the cached connections */
+	ShutdownAllConnections();
 }