Try to reduce confusion about what is a lock method identifier, a lock

method control structure, or a table of control structures.

. Use type LOCKMASK where an int is not a counter.

. Get rid of INVALID_TABLEID, use INVALID_LOCKMETHOD instead.

. Use INVALID_LOCKMETHOD instead of (LOCKMETHOD) NULL, because
  LOCKMETHOD is not a pointer.

. Define and use macro LockMethodIsValid.

. Rename LOCKMETHOD to LOCKMETHODID.

. Remove global variable LongTermTableId in lmgr.c, because it is
  never used.

. Make LockTableId static in lmgr.c, because it is used nowhere else.
  Why not remove it and use DEFAULT_LOCKMETHOD?

. Rename the lock method control structure from LOCKMETHODTABLE to
  LockMethodData.  Introduce a pointer type named LockMethod.

. Remove elog(FATAL) after InitLockTable() call in
  CreateSharedMemoryAndSemaphores(), because if something goes wrong,
  there is elog(FATAL) in LockMethodTableInit(), and if this doesn't
  help, an elog(ERROR) in InitLockTable() is promoted to FATAL.

. Make InitLockTable() void, because its only caller does not use its
  return value any more.

. Rename variables in lock.c to avoid statements like
        LockMethodTable[NumLockMethods] = lockMethodTable;
        lockMethodTable = LockMethodTable[lockmethod];

. Change LOCKMETHODID type to uint16 to fit into struct LOCKTAG.

. Remove static variables BITS_OFF and BITS_ON from lock.c, because
  I agree to this doubt:
 * XXX is a fetch from a static array really faster than a shift?

. Define and use macros LOCKBIT_ON/OFF.


Manfred Koizar

8 files changed, 153 insertions, 181 deletions

diff --git a/src/backend/storage/ipc/ipci.c b/src/backend/storage/ipc/ipci.c
index 2494d13a7a3..982846843a5 100644
--- a/src/backend/storage/ipc/ipci.c
+++ b/src/backend/storage/ipc/ipci.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.58 2003/11/29 19:51:56 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.59 2003/12/01 21:59:25 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -111,8 +111,7 @@ CreateSharedMemoryAndSemaphores(bool makePrivate,
 	 * Set up lock manager
 	 */
 	InitLocks();
-	if (InitLockTable(maxBackends) == INVALID_TABLEID)
-		elog(FATAL, "could not create the lock table");
+	InitLockTable(maxBackends);
 
 	/*
 	 * Set up process table
diff --git a/src/backend/storage/lmgr/deadlock.c b/src/backend/storage/lmgr/deadlock.c
index c121b5c9f0e..905b96f66bf 100644
--- a/src/backend/storage/lmgr/deadlock.c
+++ b/src/backend/storage/lmgr/deadlock.c
@@ -12,7 +12,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/deadlock.c,v 1.26 2003/11/29 19:51:56 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/deadlock.c,v 1.27 2003/12/01 21:59:25 momjian Exp $
  *
  *	Interface:
  *
@@ -428,7 +428,7 @@ FindLockCycleRecurse(PGPROC *checkProc,
 	LOCK	   *lock;
 	PROCLOCK   *proclock;
 	SHM_QUEUE  *lockHolders;
-	LOCKMETHODTABLE *lockMethodTable;
+	LockMethod	lockMethodTable;
 	PROC_QUEUE *waitQueue;
 	int			queue_size;
 	int			conflictMask;
diff --git a/src/backend/storage/lmgr/lmgr.c b/src/backend/storage/lmgr/lmgr.c
index 6e6d7d4e5fd..41e2df3a9be 100644
--- a/src/backend/storage/lmgr/lmgr.c
+++ b/src/backend/storage/lmgr/lmgr.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/lmgr.c,v 1.61 2003/11/29 19:51:56 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/lmgr.c,v 1.62 2003/12/01 21:59:25 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -65,26 +65,24 @@ static LOCKMASK LockConflicts[] = {
 
 };
 
-LOCKMETHOD	LockTableId = (LOCKMETHOD) NULL;
-LOCKMETHOD	LongTermTableId = (LOCKMETHOD) NULL;
+static	LOCKMETHODID	LockTableId = INVALID_LOCKMETHOD;
 
 /*
  * Create the lock table described by LockConflicts
  */
-LOCKMETHOD
+void
 InitLockTable(int maxBackends)
 {
-	int			lockmethod;
+	LOCKMETHODID	LongTermTableId;
 
 	/* number of lock modes is lengthof()-1 because of dummy zero */
-	lockmethod = LockMethodTableInit("LockTable",
-									 LockConflicts,
-									 lengthof(LockConflicts) - 1,
-									 maxBackends);
-	LockTableId = lockmethod;
-
-	if (!(LockTableId))
+	LockTableId = LockMethodTableInit("LockTable",
+									  LockConflicts,
+									  lengthof(LockConflicts) - 1,
+									  maxBackends);
+	if (!LockMethodIsValid(LockTableId))
 		elog(ERROR, "could not initialize lock table");
+	Assert(LockTableId == DEFAULT_LOCKMETHOD);
 
 #ifdef USER_LOCKS
 
@@ -92,11 +90,10 @@ InitLockTable(int maxBackends)
 	 * Allocate another tableId for long-term locks
 	 */
 	LongTermTableId = LockMethodTableRename(LockTableId);
-	if (!(LongTermTableId))
+	if (!LockMethodIsValid(LongTermTableId))
 		elog(ERROR, "could not rename long-term lock table");
+	Assert(LongTermTableId == USER_LOCKMETHOD);
 #endif
-
-	return LockTableId;
 }
 
 /*
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index c548dd5db74..6b450a1d358 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/lock.c,v 1.129 2003/11/29 19:51:56 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/lock.c,v 1.130 2003/12/01 21:59:25 momjian Exp $
  *
  * NOTES
  *	  Outside modules can create a lock table and acquire/release
@@ -46,7 +46,7 @@ int			max_locks_per_xact; /* set by guc.c */
 #define NLOCKENTS(maxBackends)	(max_locks_per_xact * (maxBackends))
 
 
-static int WaitOnLock(LOCKMETHOD lockmethod, LOCKMODE lockmode,
+static int WaitOnLock(LOCKMETHODID lockmethodid, LOCKMODE lockmode,
 		   LOCK *lock, PROCLOCK *proclock);
 static void LockCountMyLocks(SHMEM_OFFSET lockOffset, PGPROC *proc,
 				 int *myHolding);
@@ -111,7 +111,7 @@ LOCK_PRINT(const char *where, const LOCK *lock, LOCKMODE type)
 			 "req(%d,%d,%d,%d,%d,%d,%d)=%d "
 			 "grant(%d,%d,%d,%d,%d,%d,%d)=%d wait(%d) type(%s)",
 			 where, MAKE_OFFSET(lock),
-			 lock->tag.lockmethod, lock->tag.relId, lock->tag.dbId,
+			 lock->tag.lockmethodid, lock->tag.relId, lock->tag.dbId,
 			 lock->tag.objId.blkno, lock->grantMask,
 			 lock->requested[1], lock->requested[2], lock->requested[3],
 			 lock->requested[4], lock->requested[5], lock->requested[6],
@@ -150,19 +150,9 @@ PROCLOCK_PRINT(const char *where, const PROCLOCK *proclockP)
 
 
 /*
- * These are to simplify/speed up some bit arithmetic.
- *
- * XXX is a fetch from a static array really faster than a shift?
- * Wouldn't bet on it...
+ * map from lock method id to the lock table structure
  */
-
-static LOCKMASK BITS_OFF[MAX_LOCKMODES];
-static LOCKMASK BITS_ON[MAX_LOCKMODES];
-
-/*
- * map from lockmethod to the lock table structure
- */
-static LOCKMETHODTABLE *LockMethodTable[MAX_LOCK_METHODS];
+static LockMethod LockMethods[MAX_LOCK_METHODS];
 
 static int	NumLockMethods;
 
@@ -173,28 +163,20 @@ static int	NumLockMethods;
 void
 InitLocks(void)
 {
-	int			i;
-	int			bit;
-
-	bit = 1;
-	for (i = 0; i < MAX_LOCKMODES; i++, bit <<= 1)
-	{
-		BITS_ON[i] = bit;
-		BITS_OFF[i] = ~bit;
-	}
+	/* NOP */
 }
 
 
 /*
  * Fetch the lock method table associated with a given lock
  */
-LOCKMETHODTABLE *
+LockMethod
 GetLocksMethodTable(LOCK *lock)
 {
-	LOCKMETHOD	lockmethod = LOCK_LOCKMETHOD(*lock);
+	LOCKMETHODID	lockmethodid = LOCK_LOCKMETHOD(*lock);
 
-	Assert(lockmethod > 0 && lockmethod < NumLockMethods);
-	return LockMethodTable[lockmethod];
+	Assert(0 < lockmethodid && lockmethodid < NumLockMethods);
+	return LockMethods[lockmethodid];
 }
 
 
@@ -205,7 +187,7 @@ GetLocksMethodTable(LOCK *lock)
  * Notes: just copying.  Should only be called once.
  */
 static void
-LockMethodInit(LOCKMETHODTABLE *lockMethodTable,
+LockMethodInit(LockMethod lockMethodTable,
 			   LOCKMASK *conflictsP,
 			   int numModes)
 {
@@ -226,13 +208,13 @@ LockMethodInit(LOCKMETHODTABLE *lockMethodTable,
  * by the postmaster are inherited by each backend, so they must be in
  * TopMemoryContext.
  */
-LOCKMETHOD
+LOCKMETHODID
 LockMethodTableInit(char *tabName,
 					LOCKMASK *conflictsP,
 					int numModes,
 					int maxBackends)
 {
-	LOCKMETHODTABLE *lockMethodTable;
+	LockMethod	newLockMethod;
 	char	   *shmemName;
 	HASHCTL		info;
 	int			hash_flags;
@@ -254,10 +236,10 @@ LockMethodTableInit(char *tabName,
 
 	/* each lock table has a header in shared memory */
 	sprintf(shmemName, "%s (lock method table)", tabName);
-	lockMethodTable = (LOCKMETHODTABLE *)
-		ShmemInitStruct(shmemName, sizeof(LOCKMETHODTABLE), &found);
+	newLockMethod = (LockMethod)
+		ShmemInitStruct(shmemName, sizeof(LockMethodData), &found);
 
-	if (!lockMethodTable)
+	if (!newLockMethod)
 		elog(FATAL, "could not initialize lock table \"%s\"", tabName);
 
 	/*
@@ -275,15 +257,15 @@ LockMethodTableInit(char *tabName,
 	 */
 	if (!found)
 	{
-		MemSet(lockMethodTable, 0, sizeof(LOCKMETHODTABLE));
-		lockMethodTable->masterLock = LockMgrLock;
-		lockMethodTable->lockmethod = NumLockMethods;
+		MemSet(newLockMethod, 0, sizeof(LockMethodData));
+		newLockMethod->masterLock = LockMgrLock;
+		newLockMethod->lockmethodid = NumLockMethods;
 	}
 
 	/*
 	 * other modules refer to the lock table by a lockmethod ID
 	 */
-	LockMethodTable[NumLockMethods] = lockMethodTable;
+	LockMethods[NumLockMethods] = newLockMethod;
 	NumLockMethods++;
 	Assert(NumLockMethods <= MAX_LOCK_METHODS);
 
@@ -297,15 +279,15 @@ LockMethodTableInit(char *tabName,
 	hash_flags = (HASH_ELEM | HASH_FUNCTION);
 
 	sprintf(shmemName, "%s (lock hash)", tabName);
-	lockMethodTable->lockHash = ShmemInitHash(shmemName,
-											  init_table_size,
-											  max_table_size,
-											  &info,
-											  hash_flags);
+	newLockMethod->lockHash = ShmemInitHash(shmemName,
+											init_table_size,
+											max_table_size,
+											&info,
+											hash_flags);
 
-	if (!lockMethodTable->lockHash)
+	if (!newLockMethod->lockHash)
 		elog(FATAL, "could not initialize lock table \"%s\"", tabName);
-	Assert(lockMethodTable->lockHash->hash == tag_hash);
+	Assert(newLockMethod->lockHash->hash == tag_hash);
 
 	/*
 	 * allocate a hash table for PROCLOCK structs.	This is used to store
@@ -317,23 +299,23 @@ LockMethodTableInit(char *tabName,
 	hash_flags = (HASH_ELEM | HASH_FUNCTION);
 
 	sprintf(shmemName, "%s (proclock hash)", tabName);
-	lockMethodTable->proclockHash = ShmemInitHash(shmemName,
-												  init_table_size,
-												  max_table_size,
-												  &info,
-												  hash_flags);
+	newLockMethod->proclockHash = ShmemInitHash(shmemName,
+												init_table_size,
+												max_table_size,
+												&info,
+												hash_flags);
 
-	if (!lockMethodTable->proclockHash)
+	if (!newLockMethod->proclockHash)
 		elog(FATAL, "could not initialize lock table \"%s\"", tabName);
 
 	/* init data structures */
-	LockMethodInit(lockMethodTable, conflictsP, numModes);
+	LockMethodInit(newLockMethod, conflictsP, numModes);
 
 	LWLockRelease(LockMgrLock);
 
 	pfree(shmemName);
 
-	return lockMethodTable->lockmethod;
+	return newLockMethod->lockmethodid;
 }
 
 /*
@@ -349,22 +331,22 @@ LockMethodTableInit(char *tabName,
  *		short term and long term locks, yet store them all in one hashtable.
  */
 
-LOCKMETHOD
-LockMethodTableRename(LOCKMETHOD lockmethod)
+LOCKMETHODID
+LockMethodTableRename(LOCKMETHODID lockmethodid)
 {
-	LOCKMETHOD	newLockMethod;
+	LOCKMETHODID	newLockMethodId;
 
 	if (NumLockMethods >= MAX_LOCK_METHODS)
 		return INVALID_LOCKMETHOD;
-	if (LockMethodTable[lockmethod] == INVALID_LOCKMETHOD)
+	if (LockMethods[lockmethodid] == INVALID_LOCKMETHOD)
 		return INVALID_LOCKMETHOD;
 
 	/* other modules refer to the lock table by a lockmethod ID */
-	newLockMethod = NumLockMethods;
+	newLockMethodId = NumLockMethods;
 	NumLockMethods++;
 
-	LockMethodTable[newLockMethod] = LockMethodTable[lockmethod];
-	return newLockMethod;
+	LockMethods[newLockMethodId] = LockMethods[lockmethodid];
+	return newLockMethodId;
 }
 
 /*
@@ -412,7 +394,7 @@ LockMethodTableRename(LOCKMETHOD lockmethod)
  *
  *										normal lock		user lock
  *
- *		lockmethod						1				2
+ *		lockmethodid					1				2
  *		tag.dbId						database oid	database oid
  *		tag.relId						rel oid or 0	0
  *		tag.objId						block id		lock id2
@@ -429,7 +411,7 @@ LockMethodTableRename(LOCKMETHOD lockmethod)
  */
 
 bool
-LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
+LockAcquire(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 			TransactionId xid, LOCKMODE lockmode, bool dontWait)
 {
 	PROCLOCK   *proclock;
@@ -438,25 +420,25 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
 	bool		found;
 	LOCK	   *lock;
 	LWLockId	masterLock;
-	LOCKMETHODTABLE *lockMethodTable;
+	LockMethod	lockMethodTable;
 	int			status;
 	int			myHolding[MAX_LOCKMODES];
 	int			i;
 
 #ifdef LOCK_DEBUG
-	if (lockmethod == USER_LOCKMETHOD && Trace_userlocks)
+	if (lockmethodid == USER_LOCKMETHOD && Trace_userlocks)
 		elog(LOG, "LockAcquire: user lock [%u] %s",
 			 locktag->objId.blkno, lock_mode_names[lockmode]);
 #endif
 
 	/* ???????? This must be changed when short term locks will be used */
-	locktag->lockmethod = lockmethod;
+	locktag->lockmethodid = lockmethodid;
 
-	Assert(lockmethod < NumLockMethods);
-	lockMethodTable = LockMethodTable[lockmethod];
+	Assert(lockmethodid < NumLockMethods);
+	lockMethodTable = LockMethods[lockmethodid];
 	if (!lockMethodTable)
 	{
-		elog(WARNING, "bad lock table id: %d", lockmethod);
+		elog(WARNING, "bad lock table id: %d", lockmethodid);
 		return FALSE;
 	}
 
@@ -666,15 +648,12 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
 		 * Construct bitmask of locks this process holds on this object.
 		 */
 		{
-			int			heldLocks = 0;
-			int			tmpMask;
+			LOCKMASK		heldLocks = 0;
 
-			for (i = 1, tmpMask = 2;
-				 i <= lockMethodTable->numLockModes;
-				 i++, tmpMask <<= 1)
+			for (i = 1; i <= lockMethodTable->numLockModes; i++)
 			{
 				if (myHolding[i] > 0)
-					heldLocks |= tmpMask;
+					heldLocks |= LOCKBIT_ON(i);
 			}
 			MyProc->heldLocks = heldLocks;
 		}
@@ -682,7 +661,7 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
 		/*
 		 * Sleep till someone wakes me up.
 		 */
-		status = WaitOnLock(lockmethod, lockmode, lock, proclock);
+		status = WaitOnLock(lockmethodid, lockmode, lock, proclock);
 
 		/*
 		 * NOTE: do not do any material change of state between here and
@@ -729,7 +708,7 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
  * known.  If NULL is passed then these values will be computed internally.
  */
 int
-LockCheckConflicts(LOCKMETHODTABLE *lockMethodTable,
+LockCheckConflicts(LockMethod lockMethodTable,
 				   LOCKMODE lockmode,
 				   LOCK *lock,
 				   PROCLOCK *proclock,
@@ -737,9 +716,8 @@ LockCheckConflicts(LOCKMETHODTABLE *lockMethodTable,
 				   int *myHolding)		/* myHolding[] array or NULL */
 {
 	int			numLockModes = lockMethodTable->numLockModes;
-	int			bitmask;
-	int			i,
-				tmpMask;
+	LOCKMASK	bitmask;
+	int			i;
 	int			localHolding[MAX_LOCKMODES];
 
 	/*
@@ -772,11 +750,10 @@ LockCheckConflicts(LOCKMETHODTABLE *lockMethodTable,
 
 	/* Compute mask of lock types held by other processes */
 	bitmask = 0;
-	tmpMask = 2;
-	for (i = 1; i <= numLockModes; i++, tmpMask <<= 1)
+	for (i = 1; i <= numLockModes; i++)
 	{
 		if (lock->granted[i] != myHolding[i])
-			bitmask |= tmpMask;
+			bitmask |= LOCKBIT_ON(i);
 	}
 
 	/*
@@ -842,9 +819,9 @@ GrantLock(LOCK *lock, PROCLOCK *proclock, LOCKMODE lockmode)
 {
 	lock->nGranted++;
 	lock->granted[lockmode]++;
-	lock->grantMask |= BITS_ON[lockmode];
+	lock->grantMask |= LOCKBIT_ON(lockmode);
 	if (lock->granted[lockmode] == lock->requested[lockmode])
-		lock->waitMask &= BITS_OFF[lockmode];
+		lock->waitMask &= LOCKBIT_OFF(lockmode);
 	LOCK_PRINT("GrantLock", lock, lockmode);
 	Assert((lock->nGranted > 0) && (lock->granted[lockmode] > 0));
 	Assert(lock->nGranted <= lock->nRequested);
@@ -862,14 +839,14 @@ GrantLock(LOCK *lock, PROCLOCK *proclock, LOCKMODE lockmode)
  * The locktable's masterLock must be held at entry.
  */
 static int
-WaitOnLock(LOCKMETHOD lockmethod, LOCKMODE lockmode,
+WaitOnLock(LOCKMETHODID lockmethodid, LOCKMODE lockmode,
 		   LOCK *lock, PROCLOCK *proclock)
 {
-	LOCKMETHODTABLE *lockMethodTable = LockMethodTable[lockmethod];
+	LockMethod	lockMethodTable = LockMethods[lockmethodid];
 	char	   *new_status,
 			   *old_status;
 
-	Assert(lockmethod < NumLockMethods);
+	Assert(lockmethodid < NumLockMethods);
 
 	LOCK_PRINT("WaitOnLock: sleeping on lock", lock, lockmode);
 
@@ -957,7 +934,7 @@ RemoveFromWaitQueue(PGPROC *proc)
 	waitLock->requested[lockmode]--;
 	/* don't forget to clear waitMask bit if appropriate */
 	if (waitLock->granted[lockmode] == waitLock->requested[lockmode])
-		waitLock->waitMask &= BITS_OFF[lockmode];
+		waitLock->waitMask &= LOCKBIT_OFF(lockmode);
 
 	/* Clean up the proc's own state */
 	proc->waitLock = NULL;
@@ -968,7 +945,7 @@ RemoveFromWaitQueue(PGPROC *proc)
 }
 
 /*
- * LockRelease -- look up 'locktag' in lock table 'lockmethod' and
+ * LockRelease -- look up 'locktag' in lock table 'lockmethodid' and
  *		release one 'lockmode' lock on it.
  *
  * Side Effects: find any waiting processes that are now wakable,
@@ -978,27 +955,27 @@ RemoveFromWaitQueue(PGPROC *proc)
  *		come along and request the lock.)
  */
 bool
-LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag,
+LockRelease(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 			TransactionId xid, LOCKMODE lockmode)
 {
 	LOCK	   *lock;
 	LWLockId	masterLock;
-	LOCKMETHODTABLE *lockMethodTable;
+	LockMethod	lockMethodTable;
 	PROCLOCK   *proclock;
 	PROCLOCKTAG proclocktag;
 	HTAB	   *proclockTable;
 	bool		wakeupNeeded = false;
 
 #ifdef LOCK_DEBUG
-	if (lockmethod == USER_LOCKMETHOD && Trace_userlocks)
+	if (lockmethodid == USER_LOCKMETHOD && Trace_userlocks)
 		elog(LOG, "LockRelease: user lock tag [%u] %d", locktag->objId.blkno, lockmode);
 #endif
 
 	/* ???????? This must be changed when short term locks will be used */
-	locktag->lockmethod = lockmethod;
+	locktag->lockmethodid = lockmethodid;
 
-	Assert(lockmethod < NumLockMethods);
-	lockMethodTable = LockMethodTable[lockmethod];
+	Assert(lockmethodid < NumLockMethods);
+	lockMethodTable = LockMethods[lockmethodid];
 	if (!lockMethodTable)
 	{
 		elog(WARNING, "lockMethodTable is null in LockRelease");
@@ -1045,7 +1022,7 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag,
 	{
 		LWLockRelease(masterLock);
 #ifdef USER_LOCKS
-		if (lockmethod == USER_LOCKMETHOD)
+		if (lockmethodid == USER_LOCKMETHOD)
 			elog(WARNING, "no lock with this tag");
 		else
 #endif
@@ -1083,7 +1060,7 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag,
 	if (lock->granted[lockmode] == 0)
 	{
 		/* change the conflict mask.  No more of this lock type. */
-		lock->grantMask &= BITS_OFF[lockmode];
+		lock->grantMask &= LOCKBIT_OFF(lockmode);
 	}
 
 	LOCK_PRINT("LockRelease: updated", lock, lockmode);
@@ -1173,29 +1150,29 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag,
  * specified XID are released.
  */
 bool
-LockReleaseAll(LOCKMETHOD lockmethod, PGPROC *proc,
+LockReleaseAll(LOCKMETHODID lockmethodid, PGPROC *proc,
 			   bool allxids, TransactionId xid)
 {
 	SHM_QUEUE  *procHolders = &(proc->procHolders);
 	PROCLOCK   *proclock;
 	PROCLOCK   *nextHolder;
 	LWLockId	masterLock;
-	LOCKMETHODTABLE *lockMethodTable;
+	LockMethod	lockMethodTable;
 	int			i,
 				numLockModes;
 	LOCK	   *lock;
 
 #ifdef LOCK_DEBUG
-	if (lockmethod == USER_LOCKMETHOD ? Trace_userlocks : Trace_locks)
+	if (lockmethodid == USER_LOCKMETHOD ? Trace_userlocks : Trace_locks)
 		elog(LOG, "LockReleaseAll: lockmethod=%d, pid=%d",
-			 lockmethod, proc->pid);
+			 lockmethodid, proc->pid);
 #endif
 
-	Assert(lockmethod < NumLockMethods);
-	lockMethodTable = LockMethodTable[lockmethod];
+	Assert(lockmethodid < NumLockMethods);
+	lockMethodTable = LockMethods[lockmethodid];
 	if (!lockMethodTable)
 	{
-		elog(WARNING, "bad lock method: %d", lockmethod);
+		elog(WARNING, "bad lock method: %d", lockmethodid);
 		return FALSE;
 	}
 
@@ -1220,7 +1197,7 @@ LockReleaseAll(LOCKMETHOD lockmethod, PGPROC *proc,
 		lock = (LOCK *) MAKE_PTR(proclock->tag.lock);
 
 		/* Ignore items that are not of the lockmethod to be removed */
-		if (LOCK_LOCKMETHOD(*lock) != lockmethod)
+		if (LOCK_LOCKMETHOD(*lock) != lockmethodid)
 			goto next_item;
 
 		/* If not allxids, ignore items that are of the wrong xid */
@@ -1249,7 +1226,7 @@ LockReleaseAll(LOCKMETHOD lockmethod, PGPROC *proc,
 					lock->granted[i] -= proclock->holding[i];
 					Assert(lock->requested[i] >= 0 && lock->granted[i] >= 0);
 					if (lock->granted[i] == 0)
-						lock->grantMask &= BITS_OFF[i];
+						lock->grantMask &= LOCKBIT_OFF(i);
 
 					/*
 					 * Read comments in LockRelease
@@ -1331,7 +1308,7 @@ next_item:
 	LWLockRelease(masterLock);
 
 #ifdef LOCK_DEBUG
-	if (lockmethod == USER_LOCKMETHOD ? Trace_userlocks : Trace_locks)
+	if (lockmethodid == USER_LOCKMETHOD ? Trace_userlocks : Trace_locks)
 		elog(LOG, "LockReleaseAll done");
 #endif
 
@@ -1346,7 +1323,7 @@ LockShmemSize(int maxBackends)
 
 	size += MAXALIGN(sizeof(PROC_HDR)); /* ProcGlobal */
 	size += maxBackends * MAXALIGN(sizeof(PGPROC));		/* each MyProc */
-	size += MAX_LOCK_METHODS * MAXALIGN(sizeof(LOCKMETHODTABLE));		/* each lockMethodTable */
+	size += MAX_LOCK_METHODS * MAXALIGN(sizeof(LockMethodData));		/* each lock method */
 
 	/* lockHash table */
 	size += hash_estimate_size(max_table_size, sizeof(LOCK));
@@ -1390,7 +1367,7 @@ GetLockStatusData(void)
 
 	LWLockAcquire(LockMgrLock, LW_EXCLUSIVE);
 
-	proclockTable = LockMethodTable[DEFAULT_LOCKMETHOD]->proclockHash;
+	proclockTable = LockMethods[DEFAULT_LOCKMETHOD]->proclockHash;
 
 	data->nelements = i = proclockTable->hctl->nentries;
 
@@ -1446,8 +1423,8 @@ DumpLocks(void)
 	SHM_QUEUE  *procHolders;
 	PROCLOCK   *proclock;
 	LOCK	   *lock;
-	int			lockmethod = DEFAULT_LOCKMETHOD;
-	LOCKMETHODTABLE *lockMethodTable;
+	int			lockmethodid = DEFAULT_LOCKMETHOD;
+	LockMethod	lockMethodTable;
 
 	proc = MyProc;
 	if (proc == NULL)
@@ -1455,8 +1432,8 @@ DumpLocks(void)
 
 	procHolders = &proc->procHolders;
 
-	Assert(lockmethod < NumLockMethods);
-	lockMethodTable = LockMethodTable[lockmethod];
+	Assert(lockmethodid < NumLockMethods);
+	lockMethodTable = LockMethods[lockmethodid];
 	if (!lockMethodTable)
 		return;
 
@@ -1489,8 +1466,8 @@ DumpAllLocks(void)
 	PGPROC	   *proc;
 	PROCLOCK   *proclock;
 	LOCK	   *lock;
-	int			lockmethod = DEFAULT_LOCKMETHOD;
-	LOCKMETHODTABLE *lockMethodTable;
+	int			lockmethodid = DEFAULT_LOCKMETHOD;
+	LockMethod	lockMethodTable;
 	HTAB	   *proclockTable;
 	HASH_SEQ_STATUS status;
 
@@ -1498,8 +1475,8 @@ DumpAllLocks(void)
 	if (proc == NULL)
 		return;
 
-	Assert(lockmethod < NumLockMethods);
-	lockMethodTable = LockMethodTable[lockmethod];
+	Assert(lockmethodid < NumLockMethods);
+	lockMethodTable = LockMethods[lockmethodid];
 	if (!lockMethodTable)
 		return;
 
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index 73d17f24f36..14434d059a8 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/proc.c,v 1.138 2003/11/29 19:51:57 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/proc.c,v 1.139 2003/12/01 21:59:25 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -543,14 +543,14 @@ ProcQueueInit(PROC_QUEUE *queue)
  * semaphore is normally zero, so when we try to acquire it, we sleep.
  */
 int
-ProcSleep(LOCKMETHODTABLE *lockMethodTable,
+ProcSleep(LockMethod lockMethodTable,
 		  LOCKMODE lockmode,
 		  LOCK *lock,
 		  PROCLOCK *proclock)
 {
 	LWLockId	masterLock = lockMethodTable->masterLock;
 	PROC_QUEUE *waitQueue = &(lock->waitProcs);
-	int			myHeldLocks = MyProc->heldLocks;
+	LOCKMASK	myHeldLocks = MyProc->heldLocks;
 	bool		early_deadlock = false;
 	PGPROC	   *proc;
 	int			i;
@@ -575,7 +575,7 @@ ProcSleep(LOCKMETHODTABLE *lockMethodTable,
 	 */
 	if (myHeldLocks != 0)
 	{
-		int			aheadRequests = 0;
+		LOCKMASK	aheadRequests = 0;
 
 		proc = (PGPROC *) MAKE_PTR(waitQueue->links.next);
 		for (i = 0; i < waitQueue->size; i++)
@@ -615,7 +615,7 @@ ProcSleep(LOCKMETHODTABLE *lockMethodTable,
 				break;
 			}
 			/* Nope, so advance to next waiter */
-			aheadRequests |= (1 << proc->waitLockMode);
+			aheadRequests |= LOCKBIT_ON(proc->waitLockMode);
 			proc = (PGPROC *) MAKE_PTR(proc->links.next);
 		}
 
@@ -637,7 +637,7 @@ ProcSleep(LOCKMETHODTABLE *lockMethodTable,
 	SHMQueueInsertBefore(&(proc->links), &(MyProc->links));
 	waitQueue->size++;
 
-	lock->waitMask |= (1 << lockmode);
+	lock->waitMask |= LOCKBIT_ON(lockmode);
 
 	/* Set up wait information in PGPROC object, too */
 	MyProc->waitLock = lock;
@@ -769,12 +769,12 @@ ProcWakeup(PGPROC *proc, int errType)
  *		for lock, waken any that are no longer blocked.
  */
 void
-ProcLockWakeup(LOCKMETHODTABLE *lockMethodTable, LOCK *lock)
+ProcLockWakeup(LockMethod lockMethodTable, LOCK *lock)
 {
 	PROC_QUEUE *waitQueue = &(lock->waitProcs);
 	int			queue_size = waitQueue->size;
 	PGPROC	   *proc;
-	int			aheadRequests = 0;
+	LOCKMASK	aheadRequests = 0;
 
 	Assert(queue_size >= 0);
 
@@ -815,7 +815,7 @@ ProcLockWakeup(LOCKMETHODTABLE *lockMethodTable, LOCK *lock)
 			 * Cannot wake this guy. Remember his request for later
 			 * checks.
 			 */
-			aheadRequests |= (1 << lockmode);
+			aheadRequests |= LOCKBIT_ON(lockmode);
 			proc = (PGPROC *) MAKE_PTR(proc->links.next);
 		}
 	}
diff --git a/src/include/storage/lmgr.h b/src/include/storage/lmgr.h
index cd345e08cac..fc497c72e0d 100644
--- a/src/include/storage/lmgr.h
+++ b/src/include/storage/lmgr.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/lmgr.h,v 1.41 2003/11/29 22:41:13 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/storage/lmgr.h,v 1.42 2003/12/01 21:59:25 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -40,10 +40,7 @@
  * so increase that if you want to add more modes.
  */
 
-extern LOCKMETHOD LockTableId;
-
-
-extern LOCKMETHOD InitLockTable(int maxBackends);
+extern void InitLockTable(int maxBackends);
 extern void RelationInitLockInfo(Relation relation);
 
 /* Lock a relation */
diff --git a/src/include/storage/lock.h b/src/include/storage/lock.h
index 416ec41e329..a7d66b835eb 100644
--- a/src/include/storage/lock.h
+++ b/src/include/storage/lock.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/lock.h,v 1.74 2003/11/29 22:41:13 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/storage/lock.h,v 1.75 2003/12/01 21:59:25 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,22 +42,23 @@ extern bool Debug_deadlocks;
 
 
 typedef int LOCKMASK;
-
 typedef int LOCKMODE;
-typedef int LOCKMETHOD;
-
 /* MAX_LOCKMODES cannot be larger than the # of bits in LOCKMASK */
 #define MAX_LOCKMODES		10
 
+#define LOCKBIT_ON(lockmode) (1 << (lockmode))
+#define LOCKBIT_OFF(lockmode) (~(1 << (lockmode)))
+
+typedef uint16 LOCKMETHODID;
 /* MAX_LOCK_METHODS is the number of distinct lock control tables allowed */
 #define MAX_LOCK_METHODS	3
 
-#define INVALID_TABLEID		0
-
-#define INVALID_LOCKMETHOD	INVALID_TABLEID
+#define INVALID_LOCKMETHOD	0
 #define DEFAULT_LOCKMETHOD	1
 #define USER_LOCKMETHOD		2
 
+#define LockMethodIsValid(lockmethodid) ((lockmethodid) != INVALID_LOCKMETHOD)
+
 /*
  * There is normally only one lock method, the default one.
  * If user locks are enabled, an additional lock method is present.
@@ -83,15 +84,16 @@ typedef int LOCKMETHOD;
  * masterLock -- synchronizes access to the table
  *
  */
-typedef struct LOCKMETHODTABLE
+typedef struct LockMethodData
 {
-	HTAB	   *lockHash;
-	HTAB	   *proclockHash;
-	LOCKMETHOD	lockmethod;
-	int			numLockModes;
-	int			conflictTab[MAX_LOCKMODES];
-	LWLockId	masterLock;
-} LOCKMETHODTABLE;
+	HTAB		   *lockHash;
+	HTAB		   *proclockHash;
+	LOCKMETHODID	lockmethodid;
+	int				numLockModes;
+	LOCKMASK		conflictTab[MAX_LOCKMODES];
+	LWLockId		masterLock;
+} LockMethodData;
+typedef LockMethodData *LockMethod;
 
 
 /*
@@ -115,7 +117,7 @@ typedef struct LOCKTAG
 	 */
 	OffsetNumber offnum;
 
-	uint16		lockmethod;		/* needed by userlocks */
+	LOCKMETHODID lockmethodid;		/* needed by userlocks */
 } LOCKTAG;
 
 
@@ -139,8 +141,8 @@ typedef struct LOCK
 	LOCKTAG		tag;			/* unique identifier of lockable object */
 
 	/* data */
-	int			grantMask;		/* bitmask for lock types already granted */
-	int			waitMask;		/* bitmask for lock types awaited */
+	LOCKMASK	grantMask;		/* bitmask for lock types already granted */
+	LOCKMASK	waitMask;		/* bitmask for lock types awaited */
 	SHM_QUEUE	lockHolders;	/* list of PROCLOCK objects assoc. with
 								 * lock */
 	PROC_QUEUE	waitProcs;		/* list of PGPROC objects waiting on lock */
@@ -151,7 +153,7 @@ typedef struct LOCK
 	int			nGranted;		/* total of granted[] array */
 } LOCK;
 
-#define LOCK_LOCKMETHOD(lock) ((lock).tag.lockmethod)
+#define LOCK_LOCKMETHOD(lock) ((lock).tag.lockmethodid)
 
 
 /*
@@ -204,7 +206,7 @@ typedef struct PROCLOCK
 } PROCLOCK;
 
 #define PROCLOCK_LOCKMETHOD(proclock) \
-		(((LOCK *) MAKE_PTR((proclock).tag.lock))->tag.lockmethod)
+		(((LOCK *) MAKE_PTR((proclock).tag.lock))->tag.lockmethodid)
 
 /*
  * This struct holds information passed from lmgr internals to the lock
@@ -227,17 +229,17 @@ typedef struct
  * function prototypes
  */
 extern void InitLocks(void);
-extern LOCKMETHODTABLE *GetLocksMethodTable(LOCK *lock);
-extern LOCKMETHOD LockMethodTableInit(char *tabName, LOCKMASK *conflictsP,
+extern LockMethod GetLocksMethodTable(LOCK *lock);
+extern LOCKMETHODID LockMethodTableInit(char *tabName, LOCKMASK *conflictsP,
 					int numModes, int maxBackends);
-extern LOCKMETHOD LockMethodTableRename(LOCKMETHOD lockmethod);
-extern bool LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
+extern LOCKMETHODID LockMethodTableRename(LOCKMETHODID lockmethodid);
+extern bool LockAcquire(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 			TransactionId xid, LOCKMODE lockmode, bool dontWait);
-extern bool LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag,
+extern bool LockRelease(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 			TransactionId xid, LOCKMODE lockmode);
-extern bool LockReleaseAll(LOCKMETHOD lockmethod, PGPROC *proc,
+extern bool LockReleaseAll(LOCKMETHODID lockmethodid, PGPROC *proc,
 			   bool allxids, TransactionId xid);
-extern int LockCheckConflicts(LOCKMETHODTABLE *lockMethodTable,
+extern int LockCheckConflicts(LockMethod lockMethodTable,
 				   LOCKMODE lockmode,
 				   LOCK *lock, PROCLOCK *proclock, PGPROC *proc,
 				   int *myHolding);
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h
index db84a6e9397..c7283f374cf 100644
--- a/src/include/storage/proc.h
+++ b/src/include/storage/proc.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/proc.h,v 1.66 2003/11/29 22:41:13 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/storage/proc.h,v 1.67 2003/12/01 21:59:25 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -106,10 +106,10 @@ extern void InitDummyProcess(int proctype);
 extern void ProcReleaseLocks(bool isCommit);
 
 extern void ProcQueueInit(PROC_QUEUE *queue);
-extern int ProcSleep(LOCKMETHODTABLE *lockMethodTable, LOCKMODE lockmode,
+extern int ProcSleep(LockMethod lockMethodTable, LOCKMODE lockmode,
 		  LOCK *lock, PROCLOCK *proclock);
 extern PGPROC *ProcWakeup(PGPROC *proc, int errType);
-extern void ProcLockWakeup(LOCKMETHODTABLE *lockMethodTable, LOCK *lock);
+extern void ProcLockWakeup(LockMethod lockMethodTable, LOCK *lock);
 extern bool LockWaitCancel(void);
 
 extern void ProcWaitForSignal(void);