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Simplify lock manager data structures by making a clear separation between

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the data defining the semantics of a lock method (ie, conflict resolution
table and ancillary data, which is all constant) and the hash tables
storing the current state.  The only thing we give up by this is the
ability to use separate hashtables for different lock methods, but there
is no need for that anyway.  Put some extra fields into the LockMethod
definition structs to clean up some other uglinesses, like hard-wired
tests for DEFAULT_LOCKMETHOD and USER_LOCKMETHOD.  This commit doesn't
do anything about the performance issues we were discussing, but it clears
away some of the underbrush that's in the way of fixing that.
This commit is contained in:
Tom Lane
2005-12-09 01:22:04 +00:00
parent 34848052d0
commit c599a247bb
12 changed files with 394 additions and 574 deletions
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142
src/backend/storage/lmgr/lmgr.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/lmgr/lmgr.c,v 1.79 2005/10/15 02:49:26 momjian Exp $
* $PostgreSQL: pgsql/src/backend/storage/lmgr/lmgr.c,v 1.80 2005/12/09 01:22:04 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -18,96 +18,12 @@
#include "access/subtrans.h"
#include "access/transam.h"
#include "access/xact.h"
#include "catalog/catalog.h"
#include "miscadmin.h"
#include "storage/lmgr.h"
#include "storage/procarray.h"
#include "utils/inval.h"
/*
* This conflict table defines the semantics of the various lock modes.
*/
static const LOCKMASK LockConflicts[] = {
0,
/* AccessShareLock */
(1 << AccessExclusiveLock),
/* RowShareLock */
(1 << ExclusiveLock) | (1 << AccessExclusiveLock),
/* RowExclusiveLock */
(1 << ShareLock) | (1 << ShareRowExclusiveLock) |
(1 << ExclusiveLock) | (1 << AccessExclusiveLock),
/* ShareUpdateExclusiveLock */
(1 << ShareUpdateExclusiveLock) |
(1 << ShareLock) | (1 << ShareRowExclusiveLock) |
(1 << ExclusiveLock) | (1 << AccessExclusiveLock),
/* ShareLock */
(1 << RowExclusiveLock) | (1 << ShareUpdateExclusiveLock) |
(1 << ShareRowExclusiveLock) |
(1 << ExclusiveLock) | (1 << AccessExclusiveLock),
/* ShareRowExclusiveLock */
(1 << RowExclusiveLock) | (1 << ShareUpdateExclusiveLock) |
(1 << ShareLock) | (1 << ShareRowExclusiveLock) |
(1 << ExclusiveLock) | (1 << AccessExclusiveLock),
/* ExclusiveLock */
(1 << RowShareLock) |
(1 << RowExclusiveLock) | (1 << ShareUpdateExclusiveLock) |
(1 << ShareLock) | (1 << ShareRowExclusiveLock) |
(1 << ExclusiveLock) | (1 << AccessExclusiveLock),
/* AccessExclusiveLock */
(1 << AccessShareLock) | (1 << RowShareLock) |
(1 << RowExclusiveLock) | (1 << ShareUpdateExclusiveLock) |
(1 << ShareLock) | (1 << ShareRowExclusiveLock) |
(1 << ExclusiveLock) | (1 << AccessExclusiveLock)
};
static LOCKMETHODID LockTableId = INVALID_LOCKMETHOD;
/*
* Create the lock table described by LockConflicts
*/
void
InitLockTable(void)
{
LOCKMETHODID LongTermTableId;
/* there's no zero-th table */
NumLockMethods = 1;
/*
* Create the default lock method table
*/
/* number of lock modes is lengthof()-1 because of dummy zero */
LockTableId = LockMethodTableInit("LockTable",
LockConflicts,
lengthof(LockConflicts) - 1);
if (!LockMethodIsValid(LockTableId))
elog(ERROR, "could not initialize lock table");
Assert(LockTableId == DEFAULT_LOCKMETHOD);
#ifdef USER_LOCKS
/*
* Allocate another tableId for user locks (same shared hashtable though)
*/
LongTermTableId = LockMethodTableRename(LockTableId);
if (!LockMethodIsValid(LongTermTableId))
elog(ERROR, "could not rename user lock table");
Assert(LongTermTableId == USER_LOCKMETHOD);
#endif
}
/*
* RelationInitLockInfo
* Initializes the lock information in a relation descriptor.
@@ -141,8 +57,7 @@ LockRelation(Relation relation, LOCKMODE lockmode)
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
res = LockAcquire(LockTableId, &tag, relation->rd_istemp,
lockmode, false, false);
res = LockAcquire(&tag, relation->rd_istemp, lockmode, false, false);
/*
* Check to see if the relcache entry has been invalidated while we were
@@ -178,8 +93,7 @@ ConditionalLockRelation(Relation relation, LOCKMODE lockmode)
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
res = LockAcquire(LockTableId, &tag, relation->rd_istemp,
lockmode, false, true);
res = LockAcquire(&tag, relation->rd_istemp, lockmode, false, true);
if (res == LOCKACQUIRE_NOT_AVAIL)
return false;
@@ -213,7 +127,7 @@ UnlockRelation(Relation relation, LOCKMODE lockmode)
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
LockRelease(LockTableId, &tag, lockmode, false);
LockRelease(&tag, lockmode, false);
}
/*
@@ -235,8 +149,7 @@ LockRelationForSession(LockRelId *relid, bool istemprel, LOCKMODE lockmode)
SET_LOCKTAG_RELATION(tag, relid->dbId, relid->relId);
(void) LockAcquire(LockTableId, &tag, istemprel,
lockmode, true, false);
(void) LockAcquire(&tag, istemprel, lockmode, true, false);
}
/*
@@ -249,7 +162,7 @@ UnlockRelationForSession(LockRelId *relid, LOCKMODE lockmode)
SET_LOCKTAG_RELATION(tag, relid->dbId, relid->relId);
LockRelease(LockTableId, &tag, lockmode, true);
LockRelease(&tag, lockmode, true);
}
/*
@@ -271,8 +184,7 @@ LockRelationForExtension(Relation relation, LOCKMODE lockmode)
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
(void) LockAcquire(LockTableId, &tag, relation->rd_istemp,
lockmode, false, false);
(void) LockAcquire(&tag, relation->rd_istemp, lockmode, false, false);
}
/*
@@ -287,7 +199,7 @@ UnlockRelationForExtension(Relation relation, LOCKMODE lockmode)
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
LockRelease(LockTableId, &tag, lockmode, false);
LockRelease(&tag, lockmode, false);
}
/*
@@ -306,8 +218,7 @@ LockPage(Relation relation, BlockNumber blkno, LOCKMODE lockmode)
relation->rd_lockInfo.lockRelId.relId,
blkno);
(void) LockAcquire(LockTableId, &tag, relation->rd_istemp,
lockmode, false, false);
(void) LockAcquire(&tag, relation->rd_istemp, lockmode, false, false);
}
/*
@@ -326,7 +237,7 @@ ConditionalLockPage(Relation relation, BlockNumber blkno, LOCKMODE lockmode)
relation->rd_lockInfo.lockRelId.relId,
blkno);
return (LockAcquire(LockTableId, &tag, relation->rd_istemp,
return (LockAcquire(&tag, relation->rd_istemp,
lockmode, false, true) != LOCKACQUIRE_NOT_AVAIL);
}
@@ -343,7 +254,7 @@ UnlockPage(Relation relation, BlockNumber blkno, LOCKMODE lockmode)
relation->rd_lockInfo.lockRelId.relId,
blkno);
LockRelease(LockTableId, &tag, lockmode, false);
LockRelease(&tag, lockmode, false);
}
/*
@@ -364,8 +275,7 @@ LockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode)
ItemPointerGetBlockNumber(tid),
ItemPointerGetOffsetNumber(tid));
(void) LockAcquire(LockTableId, &tag, relation->rd_istemp,
lockmode, false, false);
(void) LockAcquire(&tag, relation->rd_istemp, lockmode, false, false);
}
/*
@@ -385,7 +295,7 @@ ConditionalLockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode)
ItemPointerGetBlockNumber(tid),
ItemPointerGetOffsetNumber(tid));
return (LockAcquire(LockTableId, &tag, relation->rd_istemp,
return (LockAcquire(&tag, relation->rd_istemp,
lockmode, false, true) != LOCKACQUIRE_NOT_AVAIL);
}
@@ -403,7 +313,7 @@ UnlockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode)
ItemPointerGetBlockNumber(tid),
ItemPointerGetOffsetNumber(tid));
LockRelease(LockTableId, &tag, lockmode, false);
LockRelease(&tag, lockmode, false);
}
/*
@@ -420,8 +330,7 @@ XactLockTableInsert(TransactionId xid)
SET_LOCKTAG_TRANSACTION(tag, xid);
(void) LockAcquire(LockTableId, &tag, false,
ExclusiveLock, false, false);
(void) LockAcquire(&tag, false, ExclusiveLock, false, false);
}
/*
@@ -439,7 +348,7 @@ XactLockTableDelete(TransactionId xid)
SET_LOCKTAG_TRANSACTION(tag, xid);
LockRelease(LockTableId, &tag, ExclusiveLock, false);
LockRelease(&tag, ExclusiveLock, false);
}
/*
@@ -466,10 +375,9 @@ XactLockTableWait(TransactionId xid)
SET_LOCKTAG_TRANSACTION(tag, xid);
(void) LockAcquire(LockTableId, &tag, false,
ShareLock, false, false);
(void) LockAcquire(&tag, false, ShareLock, false, false);
LockRelease(LockTableId, &tag, ShareLock, false);
LockRelease(&tag, ShareLock, false);
if (!TransactionIdIsInProgress(xid))
break;
@@ -502,11 +410,11 @@ ConditionalXactLockTableWait(TransactionId xid)
SET_LOCKTAG_TRANSACTION(tag, xid);
if (LockAcquire(LockTableId, &tag, false,
if (LockAcquire(&tag, false,
ShareLock, false, true) == LOCKACQUIRE_NOT_AVAIL)
return false;
LockRelease(LockTableId, &tag, ShareLock, false);
LockRelease(&tag, ShareLock, false);
if (!TransactionIdIsInProgress(xid))
break;
@@ -545,8 +453,7 @@ LockDatabaseObject(Oid classid, Oid objid, uint16 objsubid,
objid,
objsubid);
(void) LockAcquire(LockTableId, &tag, false,
lockmode, false, false);
(void) LockAcquire(&tag, false, lockmode, false, false);
}
/*
@@ -564,7 +471,7 @@ UnlockDatabaseObject(Oid classid, Oid objid, uint16 objsubid,
objid,
objsubid);
LockRelease(LockTableId, &tag, lockmode, false);
LockRelease(&tag, lockmode, false);
}
/*
@@ -584,8 +491,7 @@ LockSharedObject(Oid classid, Oid objid, uint16 objsubid,
objid,
objsubid);
(void) LockAcquire(LockTableId, &tag, false,
lockmode, false, false);
(void) LockAcquire(&tag, false, lockmode, false, false);
}
/*
@@ -603,5 +509,5 @@ UnlockSharedObject(Oid classid, Oid objid, uint16 objsubid,
objid,
objsubid);
LockRelease(LockTableId, &tag, lockmode, false);
LockRelease(&tag, lockmode, false);
}