/* ----------------------------------------------------------------
* ExecReScanBitmapHeapScan(node)
* ----------------------------------------------------------------
*/
void
ExecReScanBitmapHeapScan(BitmapHeapScanState *node)
{
PlanState *outerPlan = outerPlanState(node);
/* rescan to release any page pin */
heap_rescan(node->ss.ss_currentScanDesc, NULL);
if (node->tbmiterator)
tbm_end_iterate(node->tbmiterator);
if (node->prefetch_iterator)
tbm_end_iterate(node->prefetch_iterator);
if (node->shared_tbmiterator)
tbm_end_shared_iterate(node->shared_tbmiterator);
if (node->shared_prefetch_iterator)
tbm_end_shared_iterate(node->shared_prefetch_iterator);
if (node->tbm)
tbm_free(node->tbm);
node->tbm = NULL;
node->tbmiterator = NULL;
node->tbmres = NULL;
node->prefetch_iterator = NULL;
node->initialized = false;
node->shared_tbmiterator = NULL;
node->shared_prefetch_iterator = NULL;
ExecScanReScan(&node->ss);
/*
* if chgParam of subnode is not null then plan will be re-scanned by
* first ExecProcNode.
*/
if (outerPlan->chgParam == NULL)
ExecReScan(outerPlan);
}
/* ----------------------------------------------------------------
* ExecEndBitmapHeapScan
* ----------------------------------------------------------------
*/
void
ExecEndBitmapHeapScan(BitmapHeapScanState *node)
{
Relation relation;
HeapScanDesc scanDesc;
/*
* extract information from the node
*/
relation = node->ss.ss_currentRelation;
scanDesc = node->ss.ss_currentScanDesc;
/*
* Free the exprcontext
*/
ExecFreeExprContext(&node->ss.ps);
/*
* clear out tuple table slots
*/
ExecClearTuple(node->ss.ps.ps_ResultTupleSlot);
ExecClearTuple(node->ss.ss_ScanTupleSlot);
/*
* close down subplans
*/
ExecEndNode(outerPlanState(node));
/*
* release bitmap if any
*/
if (node->tbmiterator)
tbm_end_iterate(node->tbmiterator);
if (node->prefetch_iterator)
tbm_end_iterate(node->prefetch_iterator);
if (node->tbm)
tbm_free(node->tbm);
if (node->shared_tbmiterator)
tbm_end_shared_iterate(node->shared_tbmiterator);
if (node->shared_prefetch_iterator)
tbm_end_shared_iterate(node->shared_prefetch_iterator);
/*
* close heap scan
*/
heap_endscan(scanDesc);
/*
* close the heap relation.
*/
ExecCloseScanRelation(relation);
}
/* ----------------------------------------------------------------
* ExecReScanBitmapHeapScan(node)
* ----------------------------------------------------------------
*/
void
ExecReScanBitmapHeapScan(BitmapHeapScanState *node)
{
PlanState *outerPlan = outerPlanState(node);
/* rescan to release any page pin */
heap_rescan(node->ss.ss_currentScanDesc, NULL);
if (node->tbmiterator)
tbm_end_iterate(node->tbmiterator);
if (node->prefetch_iterator)
tbm_end_iterate(node->prefetch_iterator);
if (node->shared_tbmiterator)
tbm_end_shared_iterate(node->shared_tbmiterator);
if (node->shared_prefetch_iterator)
tbm_end_shared_iterate(node->shared_prefetch_iterator);
if (node->tbm)
tbm_free(node->tbm);
node->tbm = NULL;
node->tbmiterator = NULL;
node->tbmres = NULL;
node->prefetch_iterator = NULL;
node->initialized = false;
node->shared_tbmiterator = NULL;
node->shared_prefetch_iterator = NULL;
/* Reset parallel bitmap state, if present */
if (node->pstate)
{
dsa_area *dsa = node->ss.ps.state->es_query_dsa;
node->pstate->state = BM_INITIAL;
if (DsaPointerIsValid(node->pstate->tbmiterator))
tbm_free_shared_area(dsa, node->pstate->tbmiterator);
if (DsaPointerIsValid(node->pstate->prefetch_iterator))
tbm_free_shared_area(dsa, node->pstate->prefetch_iterator);
node->pstate->tbmiterator = InvalidDsaPointer;
node->pstate->prefetch_iterator = InvalidDsaPointer;
}
ExecScanReScan(&node->ss);
/*
* if chgParam of subnode is not null then plan will be re-scanned by
* first ExecProcNode.
*/
if (outerPlan->chgParam == NULL)
ExecReScan(outerPlan);
}
/* ----------------------------------------------------------------
* ExecEndBitmapHeapScan
* ----------------------------------------------------------------
*/
void
ExecEndBitmapHeapScan(BitmapHeapScanState *node)
{
HeapScanDesc scanDesc;
/*
* extract information from the node
*/
scanDesc = node->ss.ss_currentScanDesc;
/*
* Free the exprcontext
*/
ExecFreeExprContext(&node->ss.ps);
/*
* clear out tuple table slots
*/
if (node->ss.ps.ps_ResultTupleSlot)
ExecClearTuple(node->ss.ps.ps_ResultTupleSlot);
ExecClearTuple(node->ss.ss_ScanTupleSlot);
/*
* close down subplans
*/
ExecEndNode(outerPlanState(node));
/*
* release bitmaps and buffers if any
*/
if (node->tbmiterator)
tbm_end_iterate(node->tbmiterator);
if (node->prefetch_iterator)
tbm_end_iterate(node->prefetch_iterator);
if (node->tbm)
tbm_free(node->tbm);
if (node->shared_tbmiterator)
tbm_end_shared_iterate(node->shared_tbmiterator);
if (node->shared_prefetch_iterator)
tbm_end_shared_iterate(node->shared_prefetch_iterator);
if (node->vmbuffer != InvalidBuffer)
ReleaseBuffer(node->vmbuffer);
if (node->pvmbuffer != InvalidBuffer)
ReleaseBuffer(node->pvmbuffer);
/*
* close heap scan
*/
heap_endscan(scanDesc);
}
/*
* BitmapPrefetch - Prefetch, if prefetch_pages are behind prefetch_target
*/
static inline void
BitmapPrefetch(BitmapHeapScanState *node, HeapScanDesc scan)
{
#ifdef USE_PREFETCH
ParallelBitmapHeapState *pstate = node->pstate;
if (pstate == NULL)
{
TBMIterator *prefetch_iterator = node->prefetch_iterator;
if (prefetch_iterator)
{
while (node->prefetch_pages < node->prefetch_target)
{
TBMIterateResult *tbmpre = tbm_iterate(prefetch_iterator);
if (tbmpre == NULL)
{
/* No more pages to prefetch */
tbm_end_iterate(prefetch_iterator);
node->prefetch_iterator = NULL;
break;
}
node->prefetch_pages++;
PrefetchBuffer(scan->rs_rd, MAIN_FORKNUM, tbmpre->blockno);
}
}
return;
}
if (pstate->prefetch_pages < pstate->prefetch_target)
{
TBMSharedIterator *prefetch_iterator = node->shared_prefetch_iterator;
if (prefetch_iterator)
{
while (1)
{
TBMIterateResult *tbmpre;
bool do_prefetch = false;
/*
* Recheck under the mutex. If some other process has already
* done enough prefetching then we need not to do anything.
*/
SpinLockAcquire(&pstate->mutex);
if (pstate->prefetch_pages < pstate->prefetch_target)
{
pstate->prefetch_pages++;
do_prefetch = true;
}
SpinLockRelease(&pstate->mutex);
if (!do_prefetch)
return;
tbmpre = tbm_shared_iterate(prefetch_iterator);
if (tbmpre == NULL)
{
/* No more pages to prefetch */
tbm_end_shared_iterate(prefetch_iterator);
node->shared_prefetch_iterator = NULL;
break;
}
PrefetchBuffer(scan->rs_rd, MAIN_FORKNUM, tbmpre->blockno);
}
}
}
#endif /* USE_PREFETCH */
}
/*
* BitmapPrefetch - Prefetch, if prefetch_pages are behind prefetch_target
*/
static inline void
BitmapPrefetch(BitmapHeapScanState *node, HeapScanDesc scan)
{
#ifdef USE_PREFETCH
ParallelBitmapHeapState *pstate = node->pstate;
if (pstate == NULL)
{
TBMIterator *prefetch_iterator = node->prefetch_iterator;
if (prefetch_iterator)
{
while (node->prefetch_pages < node->prefetch_target)
{
TBMIterateResult *tbmpre = tbm_iterate(prefetch_iterator);
bool skip_fetch;
if (tbmpre == NULL)
{
/* No more pages to prefetch */
tbm_end_iterate(prefetch_iterator);
node->prefetch_iterator = NULL;
break;
}
node->prefetch_pages++;
/*
* If we expect not to have to actually read this heap page,
* skip this prefetch call, but continue to run the prefetch
* logic normally. (Would it be better not to increment
* prefetch_pages?)
*
* This depends on the assumption that the index AM will
* report the same recheck flag for this future heap page as
* it did for the current heap page; which is not a certainty
* but is true in many cases.
*/
skip_fetch = (node->can_skip_fetch &&
(node->tbmres ? !node->tbmres->recheck : false) &&
VM_ALL_VISIBLE(node->ss.ss_currentRelation,
tbmpre->blockno,
&node->pvmbuffer));
if (!skip_fetch)
PrefetchBuffer(scan->rs_rd, MAIN_FORKNUM, tbmpre->blockno);
}
}
return;
}
if (pstate->prefetch_pages < pstate->prefetch_target)
{
TBMSharedIterator *prefetch_iterator = node->shared_prefetch_iterator;
if (prefetch_iterator)
{
while (1)
{
TBMIterateResult *tbmpre;
bool do_prefetch = false;
bool skip_fetch;
/*
* Recheck under the mutex. If some other process has already
* done enough prefetching then we need not to do anything.
*/
SpinLockAcquire(&pstate->mutex);
if (pstate->prefetch_pages < pstate->prefetch_target)
{
pstate->prefetch_pages++;
do_prefetch = true;
}
SpinLockRelease(&pstate->mutex);
if (!do_prefetch)
return;
tbmpre = tbm_shared_iterate(prefetch_iterator);
if (tbmpre == NULL)
{
/* No more pages to prefetch */
tbm_end_shared_iterate(prefetch_iterator);
node->shared_prefetch_iterator = NULL;
break;
}
/* As above, skip prefetch if we expect not to need page */
skip_fetch = (node->can_skip_fetch &&
(node->tbmres ? !node->tbmres->recheck : false) &&
VM_ALL_VISIBLE(node->ss.ss_currentRelation,
tbmpre->blockno,
&node->pvmbuffer));
if (!skip_fetch)
PrefetchBuffer(scan->rs_rd, MAIN_FORKNUM, tbmpre->blockno);
}
}
}
#endif /* USE_PREFETCH */
}