shmqueue.c File Reference

#include "postgres.h"
#include "storage/shmem.h"

Include dependency graph for shmqueue.c:

Go to the source code of this file.

Functions
void	SHMQueueInit (SHM_QUEUE *queue)
bool	SHMQueueIsDetached (const SHM_QUEUE *queue)
void	SHMQueueElemInit (SHM_QUEUE *queue)
void	SHMQueueDelete (SHM_QUEUE *queue)
void	SHMQueueInsertBefore (SHM_QUEUE *queue, SHM_QUEUE *elem)
void	SHMQueueInsertAfter (SHM_QUEUE *queue, SHM_QUEUE *elem)
Pointer	SHMQueueNext (const SHM_QUEUE *queue, const SHM_QUEUE *curElem, Size linkOffset)
Pointer	SHMQueuePrev (const SHM_QUEUE *queue, const SHM_QUEUE *curElem, Size linkOffset)
bool	SHMQueueEmpty (const SHM_QUEUE *queue)

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Function Documentation

void SHMQueueDelete

(

SHM_QUEUE *

queue

)

Definition at line 68 of file shmqueue.c.

References Assert, SHM_QUEUE::next, SHM_QUEUE::prev, and ShmemAddrIsValid().

Referenced by CheckTargetForConflictsIn(), CleanUpLock(), ClearOldPredicateLocks(), CreatePredXact(), DeleteChildTargetLocks(), DeleteLockTarget(), DropAllPredicateLocksFromTable(), LockAcquireExtended(), PostPrepare_Locks(), ProcWakeup(), ReleaseOneSerializableXact(), ReleasePredXact(), ReleaseRWConflict(), RemoveFromWaitQueue(), SetPossibleUnsafeConflict(), SetRWConflict(), SummarizeOldestCommittedSxact(), SyncRepCancelWait(), SyncRepCleanupAtProcExit(), SyncRepWakeQueue(), and TransferPredicateLocksToNewTarget().

{
    SHM_QUEUE  *nextElem = queue->next;
    SHM_QUEUE  *prevElem = queue->prev;

    Assert(ShmemAddrIsValid(queue));
    Assert(ShmemAddrIsValid(nextElem));
    Assert(ShmemAddrIsValid(prevElem));

    prevElem->next = queue->next;
    nextElem->prev = queue->prev;

    queue->prev = queue->next = NULL;
}

void SHMQueueElemInit

(

SHM_QUEUE *

queue

)

Definition at line 57 of file shmqueue.c.

References Assert, SHM_QUEUE::next, SHM_QUEUE::prev, and ShmemAddrIsValid().

Referenced by GetSerializableTransactionSnapshotInt(), InitAuxiliaryProcess(), InitProcess(), MarkAsPreparing(), and predicatelock_twophase_recover().

{
    Assert(ShmemAddrIsValid(queue));
    queue->prev = queue->next = NULL;
}

bool SHMQueueEmpty

(

const SHM_QUEUE *

queue

)

Definition at line 180 of file shmqueue.c.

References Assert, SHM_QUEUE::next, SHM_QUEUE::prev, and ShmemAddrIsValid().

Referenced by CheckForSerializableConflictOut(), CleanUpLock(), GetSafeSnapshot(), InitAuxiliaryProcess(), InitProcess(), lock_twophase_recover(), ProcKill(), ReleasePredicateLocks(), RemoveTargetIfNoLongerUsed(), RWConflictExists(), SetupLockInTable(), SummarizeOldestCommittedSxact(), and TransferPredicateLocksToNewTarget().

{
    Assert(ShmemAddrIsValid(queue));

    if (queue->prev == queue)
    {
        Assert(queue->next == queue);
        return TRUE;
    }
    return FALSE;
}

void SHMQueueInit

(

SHM_QUEUE *

queue

)

Definition at line 36 of file shmqueue.c.

References Assert, SHM_QUEUE::next, SHM_QUEUE::prev, and ShmemAddrIsValid().

Referenced by CreatePredicateLock(), DropAllPredicateLocksFromTable(), GetSerializableTransactionSnapshotInt(), InitPredicateLocks(), InitProcGlobal(), lock_twophase_recover(), MarkAsPreparing(), predicatelock_twophase_recover(), ProcQueueInit(), ReleaseOneSerializableXact(), SetupLockInTable(), TransferPredicateLocksToNewTarget(), and WalSndShmemInit().

{
    Assert(ShmemAddrIsValid(queue));
    queue->prev = queue->next = queue;
}

void SHMQueueInsertAfter	(	SHM_QUEUE *	queue,
		SHM_QUEUE *	elem
	)

Definition at line 108 of file shmqueue.c.

References Assert, SHM_QUEUE::next, SHM_QUEUE::prev, and ShmemAddrIsValid().

Referenced by SyncRepQueueInsert().

{
    SHM_QUEUE  *nextPtr = queue->next;

    Assert(ShmemAddrIsValid(queue));
    Assert(ShmemAddrIsValid(elem));

    elem->prev = nextPtr->prev;
    elem->next = queue->next;
    queue->next = elem;
    nextPtr->prev = elem;
}

void SHMQueueInsertBefore	(	SHM_QUEUE *	queue,
		SHM_QUEUE *	elem
	)

Definition at line 89 of file shmqueue.c.

References Assert, SHM_QUEUE::next, SHM_QUEUE::prev, and ShmemAddrIsValid().

Referenced by CreatePredicateLock(), CreatePredXact(), DeadLockCheck(), DropAllPredicateLocksFromTable(), InitPredicateLocks(), lock_twophase_recover(), PostPrepare_Locks(), ProcSleep(), ReleaseOneSerializableXact(), ReleasePredicateLocks(), ReleasePredXact(), ReleaseRWConflict(), SetPossibleUnsafeConflict(), SetRWConflict(), SetupLockInTable(), and TransferPredicateLocksToNewTarget().

{
    SHM_QUEUE  *prevPtr = queue->prev;

    Assert(ShmemAddrIsValid(queue));
    Assert(ShmemAddrIsValid(elem));

    elem->next = prevPtr->next;
    elem->prev = queue->prev;
    queue->prev = elem;
    prevPtr->next = elem;
}

bool SHMQueueIsDetached

(

const SHM_QUEUE *

queue

)

Definition at line 47 of file shmqueue.c.

References Assert, NULL, SHM_QUEUE::prev, and ShmemAddrIsValid().

Referenced by SyncRepCancelWait(), SyncRepCleanupAtProcExit(), and SyncRepWaitForLSN().

{
    Assert(ShmemAddrIsValid(queue));
    return (queue->prev == NULL);
}

Pointer SHMQueueNext	(	const SHM_QUEUE *	queue,
		const SHM_QUEUE *	curElem,
		Size	linkOffset
	)

Definition at line 145 of file shmqueue.c.

References Assert, SHM_QUEUE::next, and ShmemAddrIsValid().

Referenced by AtPrepare_PredicateLocks(), CheckTableForSerializableConflictIn(), CheckTargetForConflictsIn(), ClearOldPredicateLocks(), CreatePredXact(), DeleteChildTargetLocks(), DeleteLockTarget(), DropAllPredicateLocksFromTable(), FindLockCycleRecurse(), FirstPredXact(), FlagSxactUnsafe(), GetLockConflicts(), LockReleaseAll(), NextPredXact(), OnConflict_CheckForSerializationFailure(), PostPrepare_Locks(), PreCommit_CheckForSerializationFailure(), ReleaseOneSerializableXact(), ReleasePredicateLocks(), RWConflictExists(), SetPossibleUnsafeConflict(), SetRWConflict(), SummarizeOldestCommittedSxact(), SyncRepWakeQueue(), and TransferPredicateLocksToNewTarget().

{
    SHM_QUEUE  *elemPtr = curElem->next;

    Assert(ShmemAddrIsValid(curElem));

    if (elemPtr == queue)       /* back to the queue head? */
        return NULL;

    return (Pointer) (((char *) elemPtr) - linkOffset);
}

Pointer SHMQueuePrev	(	const SHM_QUEUE *	queue,
		const SHM_QUEUE *	curElem,
		Size	linkOffset
	)

Definition at line 164 of file shmqueue.c.

References Assert, SHM_QUEUE::prev, and ShmemAddrIsValid().

Referenced by SyncRepQueueInsert().

{
    SHM_QUEUE  *elemPtr = curElem->prev;

    Assert(ShmemAddrIsValid(curElem));

    if (elemPtr == queue)       /* back to the queue head? */
        return NULL;

    return (Pointer) (((char *) elemPtr) - linkOffset);
}