lmgr.h File Reference

#include "lib/stringinfo.h"
#include "storage/itemptr.h"
#include "storage/lock.h"
#include "utils/rel.h"

Include dependency graph for lmgr.h:

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Go to the source code of this file.

Typedefs
typedef enum XLTW_Oper	XLTW_Oper

Enumerations
enum	XLTW_Oper {   XLTW_None , XLTW_Update , XLTW_Delete , XLTW_Lock ,   XLTW_LockUpdated , XLTW_InsertIndex , XLTW_InsertIndexUnique , XLTW_FetchUpdated ,   XLTW_RecheckExclusionConstr }

Functions
void	RelationInitLockInfo (Relation relation)
void	LockRelationOid (Oid relid, LOCKMODE lockmode)
void	LockRelationId (LockRelId *relid, LOCKMODE lockmode)
bool	ConditionalLockRelationOid (Oid relid, LOCKMODE lockmode)
void	UnlockRelationId (LockRelId *relid, LOCKMODE lockmode)
void	UnlockRelationOid (Oid relid, LOCKMODE lockmode)
void	LockRelation (Relation relation, LOCKMODE lockmode)
bool	ConditionalLockRelation (Relation relation, LOCKMODE lockmode)
void	UnlockRelation (Relation relation, LOCKMODE lockmode)
bool	CheckRelationLockedByMe (Relation relation, LOCKMODE lockmode, bool orstronger)
bool	CheckRelationOidLockedByMe (Oid relid, LOCKMODE lockmode, bool orstronger)
bool	LockHasWaitersRelation (Relation relation, LOCKMODE lockmode)
void	LockRelationIdForSession (LockRelId *relid, LOCKMODE lockmode)
void	UnlockRelationIdForSession (LockRelId *relid, LOCKMODE lockmode)
void	LockRelationForExtension (Relation relation, LOCKMODE lockmode)
void	UnlockRelationForExtension (Relation relation, LOCKMODE lockmode)
bool	ConditionalLockRelationForExtension (Relation relation, LOCKMODE lockmode)
int	RelationExtensionLockWaiterCount (Relation relation)
void	LockDatabaseFrozenIds (LOCKMODE lockmode)
void	LockPage (Relation relation, BlockNumber blkno, LOCKMODE lockmode)
bool	ConditionalLockPage (Relation relation, BlockNumber blkno, LOCKMODE lockmode)
void	UnlockPage (Relation relation, BlockNumber blkno, LOCKMODE lockmode)
void	LockTuple (Relation relation, ItemPointer tid, LOCKMODE lockmode)
bool	ConditionalLockTuple (Relation relation, ItemPointer tid, LOCKMODE lockmode, bool logLockFailure)
void	UnlockTuple (Relation relation, ItemPointer tid, LOCKMODE lockmode)
void	XactLockTableInsert (TransactionId xid)
void	XactLockTableDelete (TransactionId xid)
void	XactLockTableWait (TransactionId xid, Relation rel, ItemPointer ctid, XLTW_Oper oper)
bool	ConditionalXactLockTableWait (TransactionId xid, bool logLockFailure)
void	WaitForLockers (LOCKTAG heaplocktag, LOCKMODE lockmode, bool progress)
void	WaitForLockersMultiple (List *locktags, LOCKMODE lockmode, bool progress)
uint32	SpeculativeInsertionLockAcquire (TransactionId xid)
void	SpeculativeInsertionLockRelease (TransactionId xid)
void	SpeculativeInsertionWait (TransactionId xid, uint32 token)
void	LockDatabaseObject (Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
bool	ConditionalLockDatabaseObject (Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
void	UnlockDatabaseObject (Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
void	LockSharedObject (Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
bool	ConditionalLockSharedObject (Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
void	UnlockSharedObject (Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
void	LockSharedObjectForSession (Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
void	UnlockSharedObjectForSession (Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
void	LockApplyTransactionForSession (Oid suboid, TransactionId xid, uint16 objid, LOCKMODE lockmode)
void	UnlockApplyTransactionForSession (Oid suboid, TransactionId xid, uint16 objid, LOCKMODE lockmode)
void	DescribeLockTag (StringInfo buf, const LOCKTAG *tag)
const char *	GetLockNameFromTagType (uint16 locktag_type)

Typedef Documentation

XLTW_Oper

typedef enum XLTW_Oper XLTW_Oper

Enumeration Type Documentation

XLTW_Oper

enum XLTW_Oper

Enumerator
XLTW_None
XLTW_Update
XLTW_Delete
XLTW_Lock
XLTW_LockUpdated
XLTW_InsertIndex
XLTW_InsertIndexUnique
XLTW_FetchUpdated
XLTW_RecheckExclusionConstr

Definition at line 24 of file lmgr.h.

{
    XLTW_None,
    XLTW_Update,
    XLTW_Delete,
    XLTW_Lock,
    XLTW_LockUpdated,
    XLTW_InsertIndex,
    XLTW_InsertIndexUnique,
    XLTW_FetchUpdated,
    XLTW_RecheckExclusionConstr,
} XLTW_Oper;

Function Documentation

CheckRelationLockedByMe()

bool CheckRelationLockedByMe	(	Relation	relation,
		LOCKMODE	lockmode,
		bool	orstronger
	)

Definition at line 334 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION(tag,
                         relation->rd_lockInfo.lockRelId.dbId,
                         relation->rd_lockInfo.lockRelId.relId);
 
    return LockHeldByMe(&tag, lockmode, orstronger);
}

References LockRelId::dbId, LockHeldByMe(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by addFkRecurseReferenced(), addFkRecurseReferencing(), addRangeTableEntryForRelation(), cluster_rel(), ExecGetRangeTableRelation(), rebuild_relation(), relation_open(), and try_relation_open().

CheckRelationOidLockedByMe()

bool CheckRelationOidLockedByMe	(	Oid	relid,
		LOCKMODE	lockmode,
		bool	orstronger
	)

Definition at line 351 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SetLocktagRelationOid(&tag, relid);
 
    return LockHeldByMe(&tag, lockmode, orstronger);
}

References LockHeldByMe(), and SetLocktagRelationOid().

Referenced by ATRewriteTable(), build_index_value_desc(), errdetail_apply_conflict(), rebuild_relation(), RefreshMatViewByOid(), and SetRelationHasSubclass().

ConditionalLockDatabaseObject()

bool ConditionalLockDatabaseObject	(	Oid	classid,
		Oid	objid,
		uint16	objsubid,
		LOCKMODE	lockmode
	)

Definition at line 1026 of file lmgr.c.

{
    LOCKTAG     tag;
    LOCALLOCK  *locallock;
    LockAcquireResult res;
 
    SET_LOCKTAG_OBJECT(tag,
                       MyDatabaseId,
                       classid,
                       objid,
                       objsubid);
 
    res = LockAcquireExtended(&tag, lockmode, false, true, true, &locallock,
                              false);
 
    if (res == LOCKACQUIRE_NOT_AVAIL)
        return false;
 
    /*
     * Now that we have the lock, check for invalidation messages; see notes
     * in LockRelationOid.
     */
    if (res != LOCKACQUIRE_ALREADY_CLEAR)
    {
        AcceptInvalidationMessages();
        MarkLockClear(locallock);
    }
 
    return true;
}

References AcceptInvalidationMessages(), LOCKACQUIRE_ALREADY_CLEAR, LOCKACQUIRE_NOT_AVAIL, LockAcquireExtended(), MarkLockClear(), MyDatabaseId, and SET_LOCKTAG_OBJECT.

Referenced by do_autovacuum().

ConditionalLockPage()

bool ConditionalLockPage	(	Relation	relation,
		BlockNumber	blkno,
		LOCKMODE	lockmode
	)

Definition at line 526 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_PAGE(tag,
                     relation->rd_lockInfo.lockRelId.dbId,
                     relation->rd_lockInfo.lockRelId.relId,
                     blkno);
 
    return (LockAcquire(&tag, lockmode, false, true) != LOCKACQUIRE_NOT_AVAIL);
}

References LockRelId::dbId, LockAcquire(), LOCKACQUIRE_NOT_AVAIL, LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_PAGE.

Referenced by ginInsertCleanup().

ConditionalLockRelation()

bool ConditionalLockRelation	(	Relation	relation,
		LOCKMODE	lockmode
	)

Definition at line 278 of file lmgr.c.

{
    LOCKTAG     tag;
    LOCALLOCK  *locallock;
    LockAcquireResult res;
 
    SET_LOCKTAG_RELATION(tag,
                         relation->rd_lockInfo.lockRelId.dbId,
                         relation->rd_lockInfo.lockRelId.relId);
 
    res = LockAcquireExtended(&tag, lockmode, false, true, true, &locallock,
                              false);
 
    if (res == LOCKACQUIRE_NOT_AVAIL)
        return false;
 
    /*
     * Now that we have the lock, check for invalidation messages; see notes
     * in LockRelationOid.
     */
    if (res != LOCKACQUIRE_ALREADY_CLEAR)
    {
        AcceptInvalidationMessages();
        MarkLockClear(locallock);
    }
 
    return true;
}

References AcceptInvalidationMessages(), LockRelId::dbId, LOCKACQUIRE_ALREADY_CLEAR, LOCKACQUIRE_NOT_AVAIL, LockAcquireExtended(), LockInfoData::lockRelId, MarkLockClear(), RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by lazy_truncate_heap().

ConditionalLockRelationForExtension()

bool ConditionalLockRelationForExtension	(	Relation	relation,
		LOCKMODE	lockmode
	)

Definition at line 442 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION_EXTEND(tag,
                                relation->rd_lockInfo.lockRelId.dbId,
                                relation->rd_lockInfo.lockRelId.relId);
 
    return (LockAcquire(&tag, lockmode, false, true) != LOCKACQUIRE_NOT_AVAIL);
}

References LockRelId::dbId, LockAcquire(), LOCKACQUIRE_NOT_AVAIL, LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION_EXTEND.

ConditionalLockRelationOid()

bool ConditionalLockRelationOid	(	Oid	relid,
		LOCKMODE	lockmode
	)

Definition at line 151 of file lmgr.c.

{
    LOCKTAG     tag;
    LOCALLOCK  *locallock;
    LockAcquireResult res;
 
    SetLocktagRelationOid(&tag, relid);
 
    res = LockAcquireExtended(&tag, lockmode, false, true, true, &locallock,
                              false);
 
    if (res == LOCKACQUIRE_NOT_AVAIL)
        return false;
 
    /*
     * Now that we have the lock, check for invalidation messages; see notes
     * in LockRelationOid.
     */
    if (res != LOCKACQUIRE_ALREADY_CLEAR)
    {
        AcceptInvalidationMessages();
        MarkLockClear(locallock);
    }
 
    return true;
}

References AcceptInvalidationMessages(), LOCKACQUIRE_ALREADY_CLEAR, LOCKACQUIRE_NOT_AVAIL, LockAcquireExtended(), MarkLockClear(), and SetLocktagRelationOid().

Referenced by AlterTableMoveAll(), do_autovacuum(), LockTableRecurse(), LockViewRecurse_walker(), RangeVarGetRelidExtended(), and vacuum_open_relation().

ConditionalLockSharedObject()

bool ConditionalLockSharedObject	(	Oid	classid,
		Oid	objid,
		uint16	objsubid,
		LOCKMODE	lockmode
	)

Definition at line 1106 of file lmgr.c.

{
    LOCKTAG     tag;
    LOCALLOCK  *locallock;
    LockAcquireResult res;
 
    SET_LOCKTAG_OBJECT(tag,
                       InvalidOid,
                       classid,
                       objid,
                       objsubid);
 
    res = LockAcquireExtended(&tag, lockmode, false, true, true, &locallock,
                              false);
 
    if (res == LOCKACQUIRE_NOT_AVAIL)
        return false;
 
    /*
     * Now that we have the lock, check for invalidation messages; see notes
     * in LockRelationOid.
     */
    if (res != LOCKACQUIRE_ALREADY_CLEAR)
    {
        AcceptInvalidationMessages();
        MarkLockClear(locallock);
    }
 
    return true;
}

References AcceptInvalidationMessages(), InvalidOid, LOCKACQUIRE_ALREADY_CLEAR, LOCKACQUIRE_NOT_AVAIL, LockAcquireExtended(), MarkLockClear(), and SET_LOCKTAG_OBJECT.

Referenced by EventTriggerOnLogin().

ConditionalLockTuple()

bool ConditionalLockTuple	(	Relation	relation,
		ItemPointer	tid,
		LOCKMODE	lockmode,
		bool	logLockFailure
	)

Definition at line 582 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_TUPLE(tag,
                      relation->rd_lockInfo.lockRelId.dbId,
                      relation->rd_lockInfo.lockRelId.relId,
                      ItemPointerGetBlockNumber(tid),
                      ItemPointerGetOffsetNumber(tid));
 
    return (LockAcquireExtended(&tag, lockmode, false, true, true, NULL,
                                logLockFailure) != LOCKACQUIRE_NOT_AVAIL);
}

References LockRelId::dbId, ItemPointerGetBlockNumber(), ItemPointerGetOffsetNumber(), LOCKACQUIRE_NOT_AVAIL, LockAcquireExtended(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_TUPLE.

ConditionalXactLockTableWait()

bool ConditionalXactLockTableWait	(	TransactionId	xid,
		bool	logLockFailure
	)

Definition at line 736 of file lmgr.c.

{
    LOCKTAG     tag;
    bool        first = true;
 
    for (;;)
    {
        Assert(TransactionIdIsValid(xid));
        Assert(!TransactionIdEquals(xid, GetTopTransactionIdIfAny()));
 
        SET_LOCKTAG_TRANSACTION(tag, xid);
 
        if (LockAcquireExtended(&tag, ShareLock, false, true, true, NULL,
                                logLockFailure)
            == LOCKACQUIRE_NOT_AVAIL)
            return false;
 
        LockRelease(&tag, ShareLock, false);
 
        if (!TransactionIdIsInProgress(xid))
            break;
 
        /* See XactLockTableWait about this case */
        if (!first)
            pg_usleep(1000L);
        first = false;
        xid = SubTransGetTopmostTransaction(xid);
    }
 
    return true;
}

References Assert(), GetTopTransactionIdIfAny(), LOCKACQUIRE_NOT_AVAIL, LockAcquireExtended(), LockRelease(), pg_usleep(), SET_LOCKTAG_TRANSACTION, ShareLock, SubTransGetTopmostTransaction(), TransactionIdEquals, TransactionIdIsInProgress(), and TransactionIdIsValid.

Referenced by Do_MultiXactIdWait(), heap_lock_tuple(), and heapam_tuple_lock().

DescribeLockTag()

void DescribeLockTag	(	StringInfo	buf,
		const LOCKTAG *	tag
	)

Definition at line 1243 of file lmgr.c.

{
    switch ((LockTagType) tag->locktag_type)
    {
        case LOCKTAG_RELATION:
            appendStringInfo(buf,
                             _("relation %u of database %u"),
                             tag->locktag_field2,
                             tag->locktag_field1);
            break;
        case LOCKTAG_RELATION_EXTEND:
            appendStringInfo(buf,
                             _("extension of relation %u of database %u"),
                             tag->locktag_field2,
                             tag->locktag_field1);
            break;
        case LOCKTAG_DATABASE_FROZEN_IDS:
            appendStringInfo(buf,
                             _("pg_database.datfrozenxid of database %u"),
                             tag->locktag_field1);
            break;
        case LOCKTAG_PAGE:
            appendStringInfo(buf,
                             _("page %u of relation %u of database %u"),
                             tag->locktag_field3,
                             tag->locktag_field2,
                             tag->locktag_field1);
            break;
        case LOCKTAG_TUPLE:
            appendStringInfo(buf,
                             _("tuple (%u,%u) of relation %u of database %u"),
                             tag->locktag_field3,
                             tag->locktag_field4,
                             tag->locktag_field2,
                             tag->locktag_field1);
            break;
        case LOCKTAG_TRANSACTION:
            appendStringInfo(buf,
                             _("transaction %u"),
                             tag->locktag_field1);
            break;
        case LOCKTAG_VIRTUALTRANSACTION:
            appendStringInfo(buf,
                             _("virtual transaction %d/%u"),
                             tag->locktag_field1,
                             tag->locktag_field2);
            break;
        case LOCKTAG_SPECULATIVE_TOKEN:
            appendStringInfo(buf,
                             _("speculative token %u of transaction %u"),
                             tag->locktag_field2,
                             tag->locktag_field1);
            break;
        case LOCKTAG_OBJECT:
            appendStringInfo(buf,
                             _("object %u of class %u of database %u"),
                             tag->locktag_field3,
                             tag->locktag_field2,
                             tag->locktag_field1);
            break;
        case LOCKTAG_USERLOCK:
            /* reserved for old contrib code, now on pgfoundry */
            appendStringInfo(buf,
                             _("user lock [%u,%u,%u]"),
                             tag->locktag_field1,
                             tag->locktag_field2,
                             tag->locktag_field3);
            break;
        case LOCKTAG_ADVISORY:
            appendStringInfo(buf,
                             _("advisory lock [%u,%u,%u,%u]"),
                             tag->locktag_field1,
                             tag->locktag_field2,
                             tag->locktag_field3,
                             tag->locktag_field4);
            break;
        case LOCKTAG_APPLY_TRANSACTION:
            appendStringInfo(buf,
                             _("remote transaction %u of subscription %u of database %u"),
                             tag->locktag_field3,
                             tag->locktag_field2,
                             tag->locktag_field1);
            break;
        default:
            appendStringInfo(buf,
                             _("unrecognized locktag type %d"),
                             (int) tag->locktag_type);
            break;
    }
}

References _, appendStringInfo(), buf, LOCKTAG_ADVISORY, LOCKTAG_APPLY_TRANSACTION, LOCKTAG_DATABASE_FROZEN_IDS, LOCKTAG::locktag_field1, LOCKTAG::locktag_field2, LOCKTAG::locktag_field3, LOCKTAG::locktag_field4, LOCKTAG_OBJECT, LOCKTAG_PAGE, LOCKTAG_RELATION, LOCKTAG_RELATION_EXTEND, LOCKTAG_SPECULATIVE_TOKEN, LOCKTAG_TRANSACTION, LOCKTAG_TUPLE, LOCKTAG::locktag_type, LOCKTAG_USERLOCK, and LOCKTAG_VIRTUALTRANSACTION.

Referenced by DeadLockReport(), LockAcquireExtended(), and ProcSleep().

GetLockNameFromTagType()

const char * GetLockNameFromTagType

(

uint16

locktag_type

)

Definition at line 1340 of file lmgr.c.

{
    if (locktag_type > LOCKTAG_LAST_TYPE)
        return "???";
    return LockTagTypeNames[locktag_type];
}

References LOCKTAG_LAST_TYPE, and LockTagTypeNames.

Referenced by pgstat_get_wait_event().

LockApplyTransactionForSession()

void LockApplyTransactionForSession	(	Oid	suboid,
		TransactionId	xid,
		uint16	objid,
		LOCKMODE	lockmode
	)

Definition at line 1203 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_APPLY_TRANSACTION(tag,
                                  MyDatabaseId,
                                  suboid,
                                  xid,
                                  objid);
 
    (void) LockAcquire(&tag, lockmode, true, false);
}

References LockAcquire(), MyDatabaseId, and SET_LOCKTAG_APPLY_TRANSACTION.

Referenced by pa_lock_stream(), and pa_lock_transaction().

LockDatabaseFrozenIds()

void LockDatabaseFrozenIds

(

LOCKMODE

lockmode

)

Definition at line 491 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_DATABASE_FROZEN_IDS(tag, MyDatabaseId);
 
    (void) LockAcquire(&tag, lockmode, false, false);
}

References LockAcquire(), MyDatabaseId, and SET_LOCKTAG_DATABASE_FROZEN_IDS.

Referenced by vac_update_datfrozenxid().

LockDatabaseObject()

void LockDatabaseObject	(	Oid	classid,
		Oid	objid,
		uint16	objsubid,
		LOCKMODE	lockmode
	)

Definition at line 1002 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_OBJECT(tag,
                       MyDatabaseId,
                       classid,
                       objid,
                       objsubid);
 
    (void) LockAcquire(&tag, lockmode, false, false);
 
    /* Make sure syscaches are up-to-date with any changes we waited for */
    AcceptInvalidationMessages();
}

References AcceptInvalidationMessages(), LockAcquire(), MyDatabaseId, and SET_LOCKTAG_OBJECT.

Referenced by AcquireDeletionLock(), AddEnumLabel(), AlterPublication(), AlterPublicationOptions(), get_object_address(), LockSchemaList(), RangeVarGetAndCheckCreationNamespace(), and RenameEnumLabel().

LockHasWaitersRelation()

bool LockHasWaitersRelation	(	Relation	relation,
		LOCKMODE	lockmode
	)

Definition at line 367 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION(tag,
                         relation->rd_lockInfo.lockRelId.dbId,
                         relation->rd_lockInfo.lockRelId.relId);
 
    return LockHasWaiters(&tag, lockmode, false);
}

References LockRelId::dbId, LockHasWaiters(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by count_nondeletable_pages().

LockPage()

void LockPage	(	Relation	relation,
		BlockNumber	blkno,
		LOCKMODE	lockmode
	)

Definition at line 507 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_PAGE(tag,
                     relation->rd_lockInfo.lockRelId.dbId,
                     relation->rd_lockInfo.lockRelId.relId,
                     blkno);
 
    (void) LockAcquire(&tag, lockmode, false, false);
}

References LockRelId::dbId, LockAcquire(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_PAGE.

Referenced by ginInsertCleanup().

LockRelation()

void LockRelation	(	Relation	relation,
		LOCKMODE	lockmode
	)

Definition at line 246 of file lmgr.c.

{
    LOCKTAG     tag;
    LOCALLOCK  *locallock;
    LockAcquireResult res;
 
    SET_LOCKTAG_RELATION(tag,
                         relation->rd_lockInfo.lockRelId.dbId,
                         relation->rd_lockInfo.lockRelId.relId);
 
    res = LockAcquireExtended(&tag, lockmode, false, false, true, &locallock,
                              false);
 
    /*
     * Now that we have the lock, check for invalidation messages; see notes
     * in LockRelationOid.
     */
    if (res != LOCKACQUIRE_ALREADY_CLEAR)
    {
        AcceptInvalidationMessages();
        MarkLockClear(locallock);
    }
}

References AcceptInvalidationMessages(), LockRelId::dbId, LOCKACQUIRE_ALREADY_CLEAR, LockAcquireExtended(), LockInfoData::lockRelId, MarkLockClear(), RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by index_create().

LockRelationForExtension()

void LockRelationForExtension	(	Relation	relation,
		LOCKMODE	lockmode
	)

Definition at line 424 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION_EXTEND(tag,
                                relation->rd_lockInfo.lockRelId.dbId,
                                relation->rd_lockInfo.lockRelId.relId);
 
    (void) LockAcquire(&tag, lockmode, false, false);
}

References LockRelId::dbId, LockAcquire(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION_EXTEND.

Referenced by brin_getinsertbuffer(), brin_page_cleanup(), btvacuumscan(), ExtendBufferedRelShared(), ExtendBufferedRelTo(), ginvacuumcleanup(), gistvacuumscan(), pgstat_index(), and spgvacuumscan().

LockRelationId()

void LockRelationId	(	LockRelId *	relid,
		LOCKMODE	lockmode
	)

Definition at line 185 of file lmgr.c.

{
    LOCKTAG     tag;
    LOCALLOCK  *locallock;
    LockAcquireResult res;
 
    SET_LOCKTAG_RELATION(tag, relid->dbId, relid->relId);
 
    res = LockAcquireExtended(&tag, lockmode, false, false, true, &locallock,
                              false);
 
    /*
     * Now that we have the lock, check for invalidation messages; see notes
     * in LockRelationOid.
     */
    if (res != LOCKACQUIRE_ALREADY_CLEAR)
    {
        AcceptInvalidationMessages();
        MarkLockClear(locallock);
    }
}

References AcceptInvalidationMessages(), LockRelId::dbId, LOCKACQUIRE_ALREADY_CLEAR, LockAcquireExtended(), MarkLockClear(), LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by CreateDatabaseUsingWalLog(), and ScanSourceDatabasePgClass().

LockRelationIdForSession()

void LockRelationIdForSession	(	LockRelId *	relid,
		LOCKMODE	lockmode
	)

Definition at line 391 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION(tag, relid->dbId, relid->relId);
 
    (void) LockAcquire(&tag, lockmode, true, false);
}

References LockRelId::dbId, LockAcquire(), LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by DefineIndex(), index_drop(), ReindexRelationConcurrently(), and vacuum_rel().

LockRelationOid()

void LockRelationOid	(	Oid	relid,
		LOCKMODE	lockmode
	)

Definition at line 107 of file lmgr.c.

{
    LOCKTAG     tag;
    LOCALLOCK  *locallock;
    LockAcquireResult res;
 
    SetLocktagRelationOid(&tag, relid);
 
    res = LockAcquireExtended(&tag, lockmode, false, false, true, &locallock,
                              false);
 
    /*
     * Now that we have the lock, check for invalidation messages, so that we
     * will update or flush any stale relcache entry before we try to use it.
     * RangeVarGetRelid() specifically relies on us for this.  We can skip
     * this in the not-uncommon case that we already had the same type of lock
     * being requested, since then no one else could have modified the
     * relcache entry in an undesirable way.  (In the case where our own xact
     * modifies the rel, the relcache update happens via
     * CommandCounterIncrement, not here.)
     *
     * However, in corner cases where code acts on tables (usually catalogs)
     * recursively, we might get here while still processing invalidation
     * messages in some outer execution of this function or a sibling.  The
     * "cleared" status of the lock tells us whether we really are done
     * absorbing relevant inval messages.
     */
    if (res != LOCKACQUIRE_ALREADY_CLEAR)
    {
        AcceptInvalidationMessages();
        MarkLockClear(locallock);
    }
}

References AcceptInvalidationMessages(), LOCKACQUIRE_ALREADY_CLEAR, LockAcquireExtended(), MarkLockClear(), and SetLocktagRelationOid().

Referenced by AcquireDeletionLock(), AcquireExecutorLocks(), AlterTableMoveAll(), ATExecAttachPartition(), ATExecDetachPartition(), ATPostAlterTypeCleanup(), binary_upgrade_replorigin_advance(), copy_table_data(), CreateTriggerFiringOn(), find_inheritance_children_extended(), heap_create_with_catalog(), heap_drop_with_catalog(), index_create(), IndexSetParentIndex(), InitCatCachePhase2(), load_critical_index(), lock_and_open_sequence(), LockTableRecurse(), LockViewRecurse_walker(), LogicalRepSyncTableStart(), pg_replication_origin_advance(), RangeVarCallbackForAttachIndex(), RangeVarCallbackForDropRelation(), RangeVarCallbackForReindexIndex(), RangeVarGetAndCheckCreationNamespace(), RangeVarGetRelidExtended(), relation_open(), ScanQueryForLocks(), SequenceChangePersistence(), and try_relation_open().

LockSharedObject()

void LockSharedObject	(	Oid	classid,
		Oid	objid,
		uint16	objsubid,
		LOCKMODE	lockmode
	)

Definition at line 1082 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_OBJECT(tag,
                       InvalidOid,
                       classid,
                       objid,
                       objsubid);
 
    (void) LockAcquire(&tag, lockmode, false, false);
 
    /* Make sure syscaches are up-to-date with any changes we waited for */
    AcceptInvalidationMessages();
}

References AcceptInvalidationMessages(), InvalidOid, LockAcquire(), and SET_LOCKTAG_OBJECT.

Referenced by AcquireDeletionLock(), AddRoleMems(), AddSubscriptionRelState(), AlterSubscription(), clear_subscription_skip_lsn(), createdb(), DelRoleMems(), DisableSubscription(), drop_local_obsolete_slots(), DropRole(), DropSubscription(), get_db_info(), get_object_address(), InitPostgres(), PreCommit_Notify(), replorigin_drop_by_name(), SetDatabaseHasLoginEventTriggers(), shdepLockAndCheckObject(), synchronize_slots(), and UpdateSubscriptionRelState().

LockSharedObjectForSession()

void LockSharedObjectForSession	(	Oid	classid,
		Oid	objid,
		uint16	objsubid,
		LOCKMODE	lockmode
	)

Definition at line 1163 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_OBJECT(tag,
                       InvalidOid,
                       classid,
                       objid,
                       objsubid);
 
    (void) LockAcquire(&tag, lockmode, true, false);
}

References InvalidOid, LockAcquire(), and SET_LOCKTAG_OBJECT.

Referenced by dbase_redo(), and movedb().

LockTuple()

void LockTuple	(	Relation	relation,
		ItemPointer	tid,
		LOCKMODE	lockmode
	)

Definition at line 562 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_TUPLE(tag,
                      relation->rd_lockInfo.lockRelId.dbId,
                      relation->rd_lockInfo.lockRelId.relId,
                      ItemPointerGetBlockNumber(tid),
                      ItemPointerGetOffsetNumber(tid));
 
    (void) LockAcquire(&tag, lockmode, false, false);
}

References LockRelId::dbId, ItemPointerGetBlockNumber(), ItemPointerGetOffsetNumber(), LockAcquire(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_TUPLE.

Referenced by AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), ExecMergeMatched(), ExecModifyTable(), ExecUpdate(), get_catalog_object_by_oid_extended(), heap_inplace_lock(), and movedb().

RelationExtensionLockWaiterCount()

int RelationExtensionLockWaiterCount

(

Relation

relation

)

Definition at line 459 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION_EXTEND(tag,
                                relation->rd_lockInfo.lockRelId.dbId,
                                relation->rd_lockInfo.lockRelId.relId);
 
    return LockWaiterCount(&tag);
}

References LockRelId::dbId, LockInfoData::lockRelId, LockWaiterCount(), RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION_EXTEND.

Referenced by RelationAddBlocks().

RelationInitLockInfo()

void RelationInitLockInfo

(

Relation

relation

)

Definition at line 70 of file lmgr.c.

{
    Assert(RelationIsValid(relation));
    Assert(OidIsValid(RelationGetRelid(relation)));
 
    relation->rd_lockInfo.lockRelId.relId = RelationGetRelid(relation);
 
    if (relation->rd_rel->relisshared)
        relation->rd_lockInfo.lockRelId.dbId = InvalidOid;
    else
        relation->rd_lockInfo.lockRelId.dbId = MyDatabaseId;
}

References Assert(), LockRelId::dbId, InvalidOid, LockInfoData::lockRelId, MyDatabaseId, OidIsValid, RelationData::rd_lockInfo, RelationData::rd_rel, RelationGetRelid, RelationIsValid, and LockRelId::relId.

Referenced by formrdesc(), load_relcache_init_file(), RelationBuildDesc(), and RelationBuildLocalRelation().

SpeculativeInsertionLockAcquire()

uint32 SpeculativeInsertionLockAcquire

(

TransactionId

xid

)

Definition at line 780 of file lmgr.c.

{
    LOCKTAG     tag;
 
    speculativeInsertionToken++;
 
    /*
     * Check for wrap-around. Zero means no token is held, so don't use that.
     */
    if (speculativeInsertionToken == 0)
        speculativeInsertionToken = 1;
 
    SET_LOCKTAG_SPECULATIVE_INSERTION(tag, xid, speculativeInsertionToken);
 
    (void) LockAcquire(&tag, ExclusiveLock, false, false);
 
    return speculativeInsertionToken;
}

References ExclusiveLock, LockAcquire(), SET_LOCKTAG_SPECULATIVE_INSERTION, and speculativeInsertionToken.

Referenced by ExecInsert().

SpeculativeInsertionLockRelease()

void SpeculativeInsertionLockRelease

(

TransactionId

xid

)

Definition at line 806 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_SPECULATIVE_INSERTION(tag, xid, speculativeInsertionToken);
 
    LockRelease(&tag, ExclusiveLock, false);
}

References ExclusiveLock, LockRelease(), SET_LOCKTAG_SPECULATIVE_INSERTION, and speculativeInsertionToken.

Referenced by ExecInsert().

SpeculativeInsertionWait()

void SpeculativeInsertionWait	(	TransactionId	xid,
		uint32	token
	)

Definition at line 822 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_SPECULATIVE_INSERTION(tag, xid, token);
 
    Assert(TransactionIdIsValid(xid));
    Assert(token != 0);
 
    (void) LockAcquire(&tag, ShareLock, false, false);
    LockRelease(&tag, ShareLock, false);
}

References Assert(), LockAcquire(), LockRelease(), SET_LOCKTAG_SPECULATIVE_INSERTION, ShareLock, and TransactionIdIsValid.

Referenced by _bt_doinsert(), and check_exclusion_or_unique_constraint().

UnlockApplyTransactionForSession()

void UnlockApplyTransactionForSession	(	Oid	suboid,
		TransactionId	xid,
		uint16	objid,
		LOCKMODE	lockmode
	)

Definition at line 1221 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_APPLY_TRANSACTION(tag,
                                  MyDatabaseId,
                                  suboid,
                                  xid,
                                  objid);
 
    LockRelease(&tag, lockmode, true);
}

References LockRelease(), MyDatabaseId, and SET_LOCKTAG_APPLY_TRANSACTION.

Referenced by pa_unlock_stream(), and pa_unlock_transaction().

UnlockDatabaseObject()

void UnlockDatabaseObject	(	Oid	classid,
		Oid	objid,
		uint16	objsubid,
		LOCKMODE	lockmode
	)

Definition at line 1062 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_OBJECT(tag,
                       MyDatabaseId,
                       classid,
                       objid,
                       objsubid);
 
    LockRelease(&tag, lockmode, false);
}

References LockRelease(), MyDatabaseId, and SET_LOCKTAG_OBJECT.

Referenced by get_object_address(), RangeVarGetAndCheckCreationNamespace(), and ReleaseDeletionLock().

UnlockPage()

void UnlockPage	(	Relation	relation,
		BlockNumber	blkno,
		LOCKMODE	lockmode
	)

Definition at line 542 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_PAGE(tag,
                     relation->rd_lockInfo.lockRelId.dbId,
                     relation->rd_lockInfo.lockRelId.relId,
                     blkno);
 
    LockRelease(&tag, lockmode, false);
}

References LockRelId::dbId, LockRelease(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_PAGE.

Referenced by ginInsertCleanup().

UnlockRelation()

void UnlockRelation	(	Relation	relation,
		LOCKMODE	lockmode
	)

Definition at line 314 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION(tag,
                         relation->rd_lockInfo.lockRelId.dbId,
                         relation->rd_lockInfo.lockRelId.relId);
 
    LockRelease(&tag, lockmode, false);
}

References LockRelId::dbId, LockRelease(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by lazy_truncate_heap().

UnlockRelationForExtension()

void UnlockRelationForExtension	(	Relation	relation,
		LOCKMODE	lockmode
	)

Definition at line 474 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION_EXTEND(tag,
                                relation->rd_lockInfo.lockRelId.dbId,
                                relation->rd_lockInfo.lockRelId.relId);
 
    LockRelease(&tag, lockmode, false);
}

References LockRelId::dbId, LockRelease(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_RELATION_EXTEND.

Referenced by brin_getinsertbuffer(), brin_page_cleanup(), btvacuumscan(), ExtendBufferedRelShared(), ExtendBufferedRelTo(), ginvacuumcleanup(), gistvacuumscan(), pgstat_index(), and spgvacuumscan().

UnlockRelationId()

void UnlockRelationId	(	LockRelId *	relid,
		LOCKMODE	lockmode
	)

Definition at line 214 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION(tag, relid->dbId, relid->relId);
 
    LockRelease(&tag, lockmode, false);
}

References LockRelId::dbId, LockRelease(), LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by CreateDatabaseUsingWalLog(), index_close(), relation_close(), and ScanSourceDatabasePgClass().

UnlockRelationIdForSession()

void UnlockRelationIdForSession	(	LockRelId *	relid,
		LOCKMODE	lockmode
	)

Definition at line 404 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_RELATION(tag, relid->dbId, relid->relId);
 
    LockRelease(&tag, lockmode, true);
}

References LockRelId::dbId, LockRelease(), LockRelId::relId, and SET_LOCKTAG_RELATION.

Referenced by DefineIndex(), index_drop(), ReindexRelationConcurrently(), and vacuum_rel().

UnlockRelationOid()

void UnlockRelationOid	(	Oid	relid,
		LOCKMODE	lockmode
	)

Definition at line 229 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SetLocktagRelationOid(&tag, relid);
 
    LockRelease(&tag, lockmode, false);
}

References LockRelease(), and SetLocktagRelationOid().

Referenced by AcquireExecutorLocks(), binary_upgrade_replorigin_advance(), do_autovacuum(), expand_vacuum_rel(), find_inheritance_children_extended(), InitCatCachePhase2(), load_critical_index(), LockTableRecurse(), LogicalRepSyncTableStart(), pg_replication_origin_advance(), RangeVarCallbackForAttachIndex(), RangeVarCallbackForDropRelation(), RangeVarCallbackForReindexIndex(), RangeVarGetAndCheckCreationNamespace(), RangeVarGetRelidExtended(), ReleaseDeletionLock(), RenameRelation(), ScanQueryForLocks(), and try_relation_open().

UnlockSharedObject()

void UnlockSharedObject	(	Oid	classid,
		Oid	objid,
		uint16	objsubid,
		LOCKMODE	lockmode
	)

Definition at line 1142 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_OBJECT(tag,
                       InvalidOid,
                       classid,
                       objid,
                       objsubid);
 
    LockRelease(&tag, lockmode, false);
}

References InvalidOid, LockRelease(), and SET_LOCKTAG_OBJECT.

Referenced by AddSubscriptionRelState(), AlterDatabaseSet(), createdb_failure_callback(), drop_local_obsolete_slots(), get_db_info(), get_object_address(), replorigin_drop_by_name(), and synchronize_slots().

UnlockSharedObjectForSession()

void UnlockSharedObjectForSession	(	Oid	classid,
		Oid	objid,
		uint16	objsubid,
		LOCKMODE	lockmode
	)

Definition at line 1181 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_OBJECT(tag,
                       InvalidOid,
                       classid,
                       objid,
                       objsubid);
 
    LockRelease(&tag, lockmode, true);
}

References InvalidOid, LockRelease(), and SET_LOCKTAG_OBJECT.

Referenced by dbase_redo(), and movedb().

UnlockTuple()

void UnlockTuple	(	Relation	relation,
		ItemPointer	tid,
		LOCKMODE	lockmode
	)

Definition at line 601 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_TUPLE(tag,
                      relation->rd_lockInfo.lockRelId.dbId,
                      relation->rd_lockInfo.lockRelId.relId,
                      ItemPointerGetBlockNumber(tid),
                      ItemPointerGetOffsetNumber(tid));
 
    LockRelease(&tag, lockmode, false);
}

References LockRelId::dbId, ItemPointerGetBlockNumber(), ItemPointerGetOffsetNumber(), LockRelease(), LockInfoData::lockRelId, RelationData::rd_lockInfo, LockRelId::relId, and SET_LOCKTAG_TUPLE.

Referenced by AlterDatabase(), AlterDatabaseOwner(), AlterDatabaseRefreshColl(), AlterObjectOwner_internal(), AlterRelationNamespaceInternal(), ATExecSetRelOptions(), ExecGrant_common(), ExecGrant_Relation(), ExecMergeMatched(), ExecModifyTable(), ExecUpdate(), heap_inplace_lock(), heap_inplace_unlock(), heap_inplace_update_and_unlock(), movedb(), RelationSetNewRelfilenumber(), RenameDatabase(), RenameRelationInternal(), SetDatabaseHasLoginEventTriggers(), SetRelationTableSpace(), and update_relispartition().

WaitForLockers()

void WaitForLockers	(	LOCKTAG	heaplocktag,
		LOCKMODE	lockmode,
		bool	progress
	)

Definition at line 983 of file lmgr.c.

{
    List       *l;
 
    l = list_make1(&heaplocktag);
    WaitForLockersMultiple(l, lockmode, progress);
    list_free(l);
}

References list_free(), list_make1, progress, and WaitForLockersMultiple().

Referenced by DefineIndex(), and index_drop().

WaitForLockersMultiple()

void WaitForLockersMultiple	(	List *	locktags,
		LOCKMODE	lockmode,
		bool	progress
	)

Definition at line 905 of file lmgr.c.

{
    List       *holders = NIL;
    ListCell   *lc;
    int         total = 0;
    int         done = 0;
 
    /* Done if no locks to wait for */
    if (locktags == NIL)
        return;
 
    /* Collect the transactions we need to wait on */
    foreach(lc, locktags)
    {
        LOCKTAG    *locktag = lfirst(lc);
        int         count;
 
        holders = lappend(holders,
                          GetLockConflicts(locktag, lockmode,
                                           progress ? &count : NULL));
        if (progress)
            total += count;
    }
 
    if (progress)
        pgstat_progress_update_param(PROGRESS_WAITFOR_TOTAL, total);
 
    /*
     * Note: GetLockConflicts() never reports our own xid, hence we need not
     * check for that.  Also, prepared xacts are reported and awaited.
     */
 
    /* Finally wait for each such transaction to complete */
    foreach(lc, holders)
    {
        VirtualTransactionId *lockholders = lfirst(lc);
 
        while (VirtualTransactionIdIsValid(*lockholders))
        {
            /* If requested, publish who we're going to wait for. */
            if (progress)
            {
                PGPROC     *holder = ProcNumberGetProc(lockholders->procNumber);
 
                if (holder)
                    pgstat_progress_update_param(PROGRESS_WAITFOR_CURRENT_PID,
                                                 holder->pid);
            }
            VirtualXactLock(*lockholders, true);
            lockholders++;
 
            if (progress)
                pgstat_progress_update_param(PROGRESS_WAITFOR_DONE, ++done);
        }
    }
    if (progress)
    {
        const int   index[] = {
            PROGRESS_WAITFOR_TOTAL,
            PROGRESS_WAITFOR_DONE,
            PROGRESS_WAITFOR_CURRENT_PID
        };
        const int64 values[] = {
            0, 0, 0
        };
 
        pgstat_progress_update_multi_param(3, index, values);
    }
 
    list_free_deep(holders);
}

References GetLockConflicts(), lappend(), lfirst, list_free_deep(), NIL, pgstat_progress_update_multi_param(), pgstat_progress_update_param(), PGPROC::pid, VirtualTransactionId::procNumber, ProcNumberGetProc(), progress, PROGRESS_WAITFOR_CURRENT_PID, PROGRESS_WAITFOR_DONE, PROGRESS_WAITFOR_TOTAL, values, VirtualTransactionIdIsValid, and VirtualXactLock().

Referenced by ATExecDetachPartition(), ReindexRelationConcurrently(), and WaitForLockers().

XactLockTableDelete()

void XactLockTableDelete

(

TransactionId

xid

)

Definition at line 639 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_TRANSACTION(tag, xid);
 
    LockRelease(&tag, ExclusiveLock, false);
}

References ExclusiveLock, LockRelease(), and SET_LOCKTAG_TRANSACTION.

Referenced by CommitSubTransaction().

XactLockTableInsert()

void XactLockTableInsert

(

TransactionId

xid

)

Definition at line 622 of file lmgr.c.

{
    LOCKTAG     tag;
 
    SET_LOCKTAG_TRANSACTION(tag, xid);
 
    (void) LockAcquire(&tag, ExclusiveLock, false, false);
}

References ExclusiveLock, LockAcquire(), and SET_LOCKTAG_TRANSACTION.

Referenced by AssignTransactionId().

XactLockTableWait()

void XactLockTableWait	(	TransactionId	xid,
		Relation	rel,
		ItemPointer	ctid,
		XLTW_Oper	oper
	)

Definition at line 663 of file lmgr.c.

{
    LOCKTAG     tag;
    XactLockTableWaitInfo info;
    ErrorContextCallback callback;
    bool        first = true;
 
    /*
     * If an operation is specified, set up our verbose error context
     * callback.
     */
    if (oper != XLTW_None)
    {
        Assert(RelationIsValid(rel));
        Assert(ItemPointerIsValid(ctid));
 
        info.rel = rel;
        info.ctid = ctid;
        info.oper = oper;
 
        callback.callback = XactLockTableWaitErrorCb;
        callback.arg = &info;
        callback.previous = error_context_stack;
        error_context_stack = &callback;
    }
 
    for (;;)
    {
        Assert(TransactionIdIsValid(xid));
        Assert(!TransactionIdEquals(xid, GetTopTransactionIdIfAny()));
 
        SET_LOCKTAG_TRANSACTION(tag, xid);
 
        (void) LockAcquire(&tag, ShareLock, false, false);
 
        LockRelease(&tag, ShareLock, false);
 
        if (!TransactionIdIsInProgress(xid))
            break;
 
        /*
         * If the Xid belonged to a subtransaction, then the lock would have
         * gone away as soon as it was finished; for correct tuple visibility,
         * the right action is to wait on its parent transaction to go away.
         * But instead of going levels up one by one, we can just wait for the
         * topmost transaction to finish with the same end result, which also
         * incurs less locktable traffic.
         *
         * Some uses of this function don't involve tuple visibility -- such
         * as when building snapshots for logical decoding.  It is possible to
         * see a transaction in ProcArray before it registers itself in the
         * locktable.  The topmost transaction in that case is the same xid,
         * so we try again after a short sleep.  (Don't sleep the first time
         * through, to avoid slowing down the normal case.)
         */
        if (!first)
            pg_usleep(1000L);
        first = false;
        xid = SubTransGetTopmostTransaction(xid);
    }
 
    if (oper != XLTW_None)
        error_context_stack = callback.previous;
}

References Assert(), callback(), XactLockTableWaitInfo::ctid, error_context_stack, GetTopTransactionIdIfAny(), ItemPointerIsValid(), LockAcquire(), LockRelease(), oper(), XactLockTableWaitInfo::oper, pg_usleep(), XactLockTableWaitInfo::rel, RelationIsValid, SET_LOCKTAG_TRANSACTION, ShareLock, SubTransGetTopmostTransaction(), TransactionIdEquals, TransactionIdIsInProgress(), TransactionIdIsValid, XactLockTableWaitErrorCb(), and XLTW_None.

Referenced by _bt_doinsert(), check_exclusion_or_unique_constraint(), Do_MultiXactIdWait(), heap_delete(), heap_inplace_lock(), heap_lock_tuple(), heap_lock_updated_tuple_rec(), heap_update(), heapam_index_build_range_scan(), heapam_tuple_lock(), RelationFindReplTupleByIndex(), RelationFindReplTupleSeq(), and SnapBuildWaitSnapshot().