Lmgr cleanup, new locking modes for LLL.

4 files changed, 84 insertions, 326 deletions

diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 97664f76f67..cffe640e2c3 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/buffer/bufmgr.c,v 1.39 1998/07/13 16:34:49 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/buffer/bufmgr.c,v 1.40 1998/08/01 15:26:12 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -114,18 +114,18 @@ RelationGetBufferWithBuffer(Relation relation,
 							Buffer buffer)
 {
 	BufferDesc *bufHdr;
-	LockRelId		lrelId;
 
 	if (BufferIsValid(buffer))
 	{
 		if (!BufferIsLocal(buffer))
 		{
+			LockRelId   *lrelId = &(((LockInfo)(relation->lockInfo))->lockRelId);
+			
 			bufHdr = &BufferDescriptors[buffer - 1];
-			lrelId = RelationGetLockRelId(relation);
 			SpinAcquire(BufMgrLock);
 			if (bufHdr->tag.blockNum == blockNumber &&
-				bufHdr->tag.relId.relId == lrelId.relId &&
-				bufHdr->tag.relId.dbId == lrelId.dbId)
+				bufHdr->tag.relId.relId == lrelId->relId &&
+				bufHdr->tag.relId.dbId == lrelId->dbId)
 			{
 				SpinRelease(BufMgrLock);
 				return (buffer);
@@ -1282,7 +1282,7 @@ BufferGetRelation(Buffer buffer)
 	Assert(!BufferIsLocal(buffer));		/* not supported for local buffers */
 
 	/* XXX should be a critical section */
-	relid = LockRelIdGetRelationId(BufferDescriptors[buffer - 1].tag.relId);
+	relid = BufferDescriptors[buffer - 1].tag.relId.relId;
 	relation = RelationIdGetRelation(relid);
 
 	RelationDecrementReferenceCount(relation);
diff --git a/src/backend/storage/lmgr/lmgr.c b/src/backend/storage/lmgr/lmgr.c
index 5cea3b2e1f3..cebbce364cc 100644
--- a/src/backend/storage/lmgr/lmgr.c
+++ b/src/backend/storage/lmgr/lmgr.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lmgr.c,v 1.15 1998/07/26 04:30:41 scrappy Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lmgr.c,v 1.16 1998/08/01 15:26:24 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -51,220 +51,48 @@
 #include "storage/bufmgr.h"
 #include "access/transam.h"		/* for AmiTransactionId */
 
-static void LockRelIdAssign(LockRelId *lockRelId, Oid dbId, Oid relId);
-
-/* ----------------
- *
- * ----------------
- */
-#define MaxRetries		4		/* XXX about 1/4 minute--a hack */
-
-#define IntentReadRelationLock	0x0100
-#define ReadRelationLock		0x0200
-#define IntentWriteRelationLock 0x0400
-#define WriteRelationLock		0x0800
-#define IntentReadPageLock		0x1000
-#define ReadTupleLock			0x2000
-
-#define TupleLevelLockCountMask 0x000f
-
-#define TupleLevelLockLimit		10
-
 extern Oid	MyDatabaseId;
 
-LockRelId VariableRelationLockRelId = {
-	RelOid_pg_variable,
-	InvalidOid
-};
-
-/*
- * LockRelIdGetDatabaseId --
- *		Returns database identifier for a "lock" relation identifier.
- */
-/* ----------------
- *		LockRelIdGetDatabaseId
- *
- * Note: The argument may not be correct, if it is not used soon
- *		 after it is created.
- * ----------------
- */
-#ifdef NOT_USED
-Oid
-LockRelIdGetDatabaseId(LockRelId lockRelId)
-{
-	return (lockRelId.dbId);
-}
-
-#endif
-
-/*
- * LockRelIdGetRelationId --
- *		Returns relation identifier for a "lock" relation identifier.
- */
-Oid
-LockRelIdGetRelationId(LockRelId lockRelId)
-{
-	return (lockRelId.relId);
-}
-
-/*
- * DatabaseIdIsMyDatabaseId --
- *		True iff database object identifier is valid in my present database.
- */
-#ifdef NOT_USED
-bool
-DatabaseIdIsMyDatabaseId(Oid databaseId)
-{
-	return (bool)
-	(!OidIsValid(databaseId) || databaseId == MyDatabaseId);
-}
-
-#endif
-
-/*
- * LockRelIdContainsMyDatabaseId --
- *		True iff "lock" relation identifier is valid in my present database.
- */
-#ifdef NOT_USED
-bool
-LockRelIdContainsMyDatabaseId(LockRelId lockRelId)
-{
-	return (bool)
-	(!OidIsValid(lockRelId.dbId) || lockRelId.dbId == MyDatabaseId);
-}
-
-#endif
-
 /*
  * RelationInitLockInfo --
  *		Initializes the lock information in a relation descriptor.
  */
-/* ----------------
- *		RelationInitLockInfo
- *
- *		XXX processingVariable is a hack to prevent problems during
- *		VARIABLE relation initialization.
- * ----------------
- */
 void
 RelationInitLockInfo(Relation relation)
 {
-	LockInfo	info;
-	char	   *relname;
-	Oid			relationid;
-	bool		processingVariable;
-	extern Oid	MyDatabaseId;	/* XXX use include */
-	extern GlobalMemory CacheCxt;
+	LockInfo			info;
+	char			   *relname;
+	MemoryContext		oldcxt;
+	extern Oid			MyDatabaseId;	/* XXX use include */
+	extern GlobalMemory	CacheCxt;
 
-	/* ----------------
-	 *	sanity checks
-	 * ----------------
-	 */
 	Assert(RelationIsValid(relation));
 	Assert(OidIsValid(RelationGetRelationId(relation)));
 
-	/* ----------------
-	 *	get information from relation descriptor
-	 * ----------------
-	 */
 	info = (LockInfo) relation->lockInfo;
+	
+	if (LockInfoIsValid(info))
+		return;
+	
 	relname = (char *) RelationGetRelationName(relation);
-	relationid = RelationGetRelationId(relation);
-	processingVariable = (strcmp(relname, VariableRelationName) == 0);
-
-	/* ----------------
-	 *	create a new lockinfo if not already done
-	 * ----------------
-	 */
-	if (!PointerIsValid(info))
-	{
-		MemoryContext oldcxt;
 
-		oldcxt = MemoryContextSwitchTo((MemoryContext) CacheCxt);
-		info = (LockInfo) palloc(sizeof(LockInfoData));
-		MemoryContextSwitchTo(oldcxt);
-	}
-	else if (processingVariable)
-	{
-		if (IsTransactionState())
-		{
-			TransactionIdStore(GetCurrentTransactionId(),
-							   &info->transactionIdData);
-		}
-		info->flags = 0x0;
-		return;					/* prevent an infinite loop--still true? */
-	}
-	else if (info->initialized)
-	{
-		/* ------------
-		 *	If we've already initialized we're done.
-		 * ------------
-		 */
-		return;
-	}
+	oldcxt = MemoryContextSwitchTo((MemoryContext) CacheCxt);
+	info = (LockInfo) palloc(sizeof(LockInfoData));
+	MemoryContextSwitchTo(oldcxt);
 
-	/* ----------------
-	 *	initialize lockinfo.dbId and .relId appropriately
-	 * ----------------
-	 */
+	info->lockRelId.relId = RelationGetRelationId(relation);
 	if (IsSharedSystemRelationName(relname))
-		LockRelIdAssign(&info->lockRelId, InvalidOid, relationid);
+		info->lockRelId.dbId = InvalidOid;
 	else
-		LockRelIdAssign(&info->lockRelId, MyDatabaseId, relationid);
+		info->lockRelId.dbId = MyDatabaseId;
 
-	/* ----------------
-	 *	store the transaction id in the lockInfo field
-	 * ----------------
-	 */
-	if (processingVariable)
-		TransactionIdStore(AmiTransactionId,
-						   &info->transactionIdData);
-	else if (IsTransactionState())
-		TransactionIdStore(GetCurrentTransactionId(),
-						   &info->transactionIdData);
-	else
-		StoreInvalidTransactionId(&(info->transactionIdData));
+#ifdef LowLevelLocking
+	memset(info->lockHeld, 0, sizeof(info->lockHeld));
+#endif
 
-	/* ----------------
-	 *	initialize rest of lockinfo
-	 * ----------------
-	 */
-	info->flags = 0x0;
-	info->initialized = (bool) true;
 	relation->lockInfo = (Pointer) info;
 }
 
-/* ----------------
- *		RelationDiscardLockInfo
- * ----------------
- */
-#ifdef	LOCKDEBUG
-#define LOCKDEBUG_20 \
-elog(DEBUG, "DiscardLockInfo: NULL relation->lockInfo")
-#else
-#define LOCKDEBUG_20
-#endif							/* LOCKDEBUG */
-
-/*
- * RelationDiscardLockInfo --
- *		Discards the lock information in a relation descriptor.
- */
-#ifdef NOT_USED
-void
-RelationDiscardLockInfo(Relation relation)
-{
-	if (!LockInfoIsValid(relation->lockInfo))
-	{
-		LOCKDEBUG_20;
-		return;
-	}
-
-	pfree(relation->lockInfo);
-	relation->lockInfo = NULL;
-}
-
-#endif
-
 /*
  * RelationSetLockForDescriptorOpen --
  *		Sets read locks for a relation descriptor.
@@ -337,7 +165,6 @@ RelationSetLockForRead(Relation relation)
 	{
 		RelationInitLockInfo(relation);
 		lockinfo = (LockInfo) relation->lockInfo;
-		lockinfo->flags |= ReadRelationLock;
 		MultiLockReln(lockinfo, READ_LOCK);
 		return;
 	}
@@ -433,7 +260,6 @@ RelationSetLockForWrite(Relation relation)
 	{
 		RelationInitLockInfo(relation);
 		lockinfo = (LockInfo) relation->lockInfo;
-		lockinfo->flags |= WriteRelationLock;
 		MultiLockReln(lockinfo, WRITE_LOCK);
 		return;
 	}
@@ -485,120 +311,6 @@ RelationUnsetLockForWrite(Relation relation)
 }
 
 /* ----------------
- *		RelationSetLockForTupleRead
- * ----------------
- */
-#ifdef	LOCKDEBUG
-#define LOCKDEBUG_80 \
-elog(DEBUG, "RelationSetLockForTupleRead(%s[%d,%d], 0x%x) called", \
-	 RelationGetRelationName(relation), lockRelId.dbId, lockRelId.relId, \
-	 itemPointer)
-#define LOCKDEBUG_81 \
-	 elog(DEBUG, "RelationSetLockForTupleRead() escalating")
-#else
-#define LOCKDEBUG_80
-#define LOCKDEBUG_81
-#endif							/* LOCKDEBUG */
-
-/*
- * RelationSetLockForTupleRead --
- *		Sets tuple level read lock.
- */
-#ifdef NOT_USED
-void
-RelationSetLockForTupleRead(Relation relation, ItemPointer itemPointer)
-{
-	LockInfo	lockinfo;
-	TransactionId curXact;
-
-	/* ----------------
-	 *	sanity checks
-	 * ----------------
-	 */
-	Assert(RelationIsValid(relation));
-	if (LockingDisabled())
-		return;
-
-	LOCKDEBUG_80;
-
-	/* ---------------------
-	 * If our lock info is invalid don't bother trying to short circuit
-	 * the lock manager.
-	 * ---------------------
-	 */
-	if (!LockInfoIsValid(relation->lockInfo))
-	{
-		RelationInitLockInfo(relation);
-		lockinfo = (LockInfo) relation->lockInfo;
-		lockinfo->flags |=
-			IntentReadRelationLock |
-			IntentReadPageLock |
-			ReadTupleLock;
-		MultiLockTuple(lockinfo, itemPointer, READ_LOCK);
-		return;
-	}
-	else
-		lockinfo = (LockInfo) relation->lockInfo;
-
-	/* ----------------
-	 *	no need to set a lower granularity lock
-	 * ----------------
-	 */
-	curXact = GetCurrentTransactionId();
-	if ((lockinfo->flags & ReadRelationLock) &&
-		TransactionIdEquals(curXact, lockinfo->transactionIdData))
-		return;
-
-	/* ----------------
-	 * If we don't already have a tuple lock this transaction
-	 * ----------------
-	 */
-	if (!((lockinfo->flags & ReadTupleLock) &&
-		  TransactionIdEquals(curXact, lockinfo->transactionIdData)))
-	{
-
-		lockinfo->flags |=
-			IntentReadRelationLock |
-			IntentReadPageLock |
-			ReadTupleLock;
-
-		/* clear count */
-		lockinfo->flags &= ~TupleLevelLockCountMask;
-
-	}
-	else
-	{
-		if (TupleLevelLockLimit == (TupleLevelLockCountMask &
-									lockinfo->flags))
-		{
-			LOCKDEBUG_81;
-
-			/* escalate */
-			MultiLockReln(lockinfo, READ_LOCK);
-
-			/* clear count */
-			lockinfo->flags &= ~TupleLevelLockCountMask;
-			return;
-		}
-
-		/* increment count */
-		lockinfo->flags =
-			(lockinfo->flags & ~TupleLevelLockCountMask) |
-			(1 + (TupleLevelLockCountMask & lockinfo->flags));
-	}
-
-	TransactionIdStore(curXact, &lockinfo->transactionIdData);
-
-	/* ----------------
-	 * Lock the tuple.
-	 * ----------------
-	 */
-	MultiLockTuple(lockinfo, itemPointer, READ_LOCK);
-}
-
-#endif
-
-/* ----------------
  *		RelationSetLockForReadPage
  * ----------------
  */
@@ -902,12 +614,3 @@ RelationUnsetLockForExtend(Relation relation)
 
 #endif
 
-/*
- * Create an LockRelid --- Why not just pass in a pointer to the storage?
- */
-static void
-LockRelIdAssign(LockRelId *lockRelId, Oid dbId, Oid relId)
-{
-	lockRelId->dbId = dbId;
-	lockRelId->relId = relId;
-}
diff --git a/src/backend/storage/lmgr/multi.c b/src/backend/storage/lmgr/multi.c
index 7fbd738b745..606ee4f560b 100644
--- a/src/backend/storage/lmgr/multi.c
+++ b/src/backend/storage/lmgr/multi.c
@@ -12,7 +12,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/Attic/multi.c,v 1.20 1998/07/13 16:34:51 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/Attic/multi.c,v 1.21 1998/08/01 15:26:26 vadim Exp $
  *
  * NOTES:
  *	 (1) The lock.c module assumes that the caller here is doing
@@ -36,6 +36,55 @@ static bool
 MultiRelease(LOCKMETHOD lockmethod, LOCKTAG *tag, LOCKMODE lockmode,
 			 PG_LOCK_LEVEL level);
 
+#ifdef LowLevelLocking
+
+static MASK	MultiConflicts[] = {
+	(int) NULL,
+	
+/* RowShareLock */
+	(1 << ExclusiveLock),
+
+/* RowExclusiveLock */
+	(1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) | (1 << ShareLock),
+
+/* ShareLock */
+	(1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) | 
+	(1 << RowExclusiveLock),
+
+/* ShareRowExclusiveLock */
+	(1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) | 
+	(1 << ShareLock) | (1 << RowExclusiveLock),
+	
+/* ExclusiveLock */
+	(1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) | (1 << ShareLock) | 
+	(1 << RowExclusiveLock) | (1 << RowShareLock),
+	
+/* ObjShareLock */
+	(1 << ObjExclusiveLock),
+	
+/* ObjExclusiveLock */
+	(1 << ObjExclusiveLock) | (1 << ObjShareLock),
+	
+/* ExtendLock */
+	(1 << ExtendLock)
+	
+};
+
+/*
+ * write locks have higher priority than read locks and extend locks.  May
+ * want to treat INTENT locks differently.
+ */
+static int	MultiPrios[] = {
+	(int) NULL,
+	2,
+	1,
+	2,
+	1,
+	1
+};
+
+#else
+
 /*
  * INTENT indicates to higher level that a lower level lock has been
  * set.  For example, a write lock on a tuple conflicts with a write
@@ -43,7 +92,7 @@ MultiRelease(LOCKMETHOD lockmethod, LOCKTAG *tag, LOCKMODE lockmode,
  * WRITE conflict between the tuple's intent lock and the relation's
  * write lock.
  */
-static int	MultiConflicts[] = {
+static MASK	MultiConflicts[] = {
 	(int) NULL,
 	/* All reads and writes at any level conflict with a write lock */
 	(1 << WRITE_LOCK) | (1 << WRITE_INTENT) | (1 << READ_LOCK) | (1 << READ_INTENT),
@@ -74,6 +123,8 @@ static int	MultiPrios[] = {
 	1
 };
 
+#endif	/* !LowLevelLocking */
+
 /*
  * Lock table identifier for this lock table.  The multi-level
  * lock table is ONE lock table, not three.
@@ -91,7 +142,8 @@ InitMultiLevelLocks()
 {
 	int			lockmethod;
 
-	lockmethod = LockMethodTableInit("MultiLevelLockTable", MultiConflicts, MultiPrios, 5);
+	lockmethod = LockMethodTableInit("MultiLevelLockTable", 
+				 MultiConflicts, MultiPrios, MAX_LOCKMODES - 1);
 	MultiTableId = lockmethod;
 	if (!(MultiTableId))
 		elog(ERROR, "InitMultiLocks: couldnt initialize lock table");
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 4a17d5e0f07..e039e2bfdc1 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.44 1998/07/27 19:38:23 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.45 1998/08/01 15:26:29 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1101,6 +1101,8 @@ formrdesc(char *relationName,
 	 */
 	RelationCacheInsert(relation);
 
+	RelationInitLockInfo(relation);
+	
 	/*
 	 * Determining this requires a scan on pg_class, but to do the scan
 	 * the rdesc for pg_class must already exist.  Therefore we must do
@@ -2021,6 +2023,7 @@ init_irels(void)
 		ird->rd_support = support;
 
 		RelationCacheInsert(ird);
+		RelationInitLockInfo(ird);
 	}
 }