#include "catalog/pg_am.h"
#include "miscadmin.h"
#include "pgstat.h"
+#include "postmaster/autovacuum.h"
#include "storage/bufmgr.h"
#include "storage/freespace.h"
#include "utils/builtins.h"
BrinDesc *bo_bdesc;
} BrinOpaque;
+#define BRIN_ALL_BLOCKRANGES InvalidBlockNumber
+
static BrinBuildState *initialize_brin_buildstate(Relation idxRel,
BrinRevmap *revmap, BlockNumber pagesPerRange);
static void terminate_brin_buildstate(BrinBuildState *state);
-static void brinsummarize(Relation index, Relation heapRel,
+static void brinsummarize(Relation index, Relation heapRel, BlockNumber pageRange,
double *numSummarized, double *numExisting);
static void form_and_insert_tuple(BrinBuildState *state);
static void union_tuples(BrinDesc *bdesc, BrinMemTuple *a,
* with those of the new tuple. If the tuple values are not consistent with
* the summary tuple, we need to update the index tuple.
*
+ * If autosummarization is enabled, check if we need to summarize the previous
+ * page range.
+ *
* If the range is not currently summarized (i.e. the revmap returns NULL for
- * it), there's nothing to do.
+ * it), there's nothing to do for this tuple.
*/
bool
brininsert(Relation idxRel, Datum *values, bool *nulls,
IndexInfo *indexInfo)
{
BlockNumber pagesPerRange;
+ BlockNumber origHeapBlk;
+ BlockNumber heapBlk;
BrinDesc *bdesc = (BrinDesc *) indexInfo->ii_AmCache;
BrinRevmap *revmap;
Buffer buf = InvalidBuffer;
MemoryContext tupcxt = NULL;
MemoryContext oldcxt = CurrentMemoryContext;
+ bool autosummarize = BrinGetAutoSummarize(idxRel);
revmap = brinRevmapInitialize(idxRel, &pagesPerRange, NULL);
+ /*
+ * origHeapBlk is the block number where the insertion occurred. heapBlk
+ * is the first block in the corresponding page range.
+ */
+ origHeapBlk = ItemPointerGetBlockNumber(heaptid);
+ heapBlk = (origHeapBlk / pagesPerRange) * pagesPerRange;
+
for (;;)
{
bool need_insert = false;
OffsetNumber off;
BrinTuple *brtup;
BrinMemTuple *dtup;
- BlockNumber heapBlk;
int keyno;
CHECK_FOR_INTERRUPTS();
- heapBlk = ItemPointerGetBlockNumber(heaptid);
- /* normalize the block number to be the first block in the range */
- heapBlk = (heapBlk / pagesPerRange) * pagesPerRange;
- brtup = brinGetTupleForHeapBlock(revmap, heapBlk, &buf, &off, NULL,
- BUFFER_LOCK_SHARE, NULL);
+ /*
+ * If auto-summarization is enabled and we just inserted the first
+ * tuple into the first block of a new non-first page range, request a
+ * summarization run of the previous range.
+ */
+ if (autosummarize &&
+ heapBlk > 0 &&
+ heapBlk == origHeapBlk &&
+ ItemPointerGetOffsetNumber(heaptid) == FirstOffsetNumber)
+ {
+ BlockNumber lastPageRange = heapBlk - 1;
+ BrinTuple *lastPageTuple;
+
+ lastPageTuple =
+ brinGetTupleForHeapBlock(revmap, lastPageRange, &buf, &off,
+ NULL, BUFFER_LOCK_SHARE, NULL);
+ if (!lastPageTuple)
+ AutoVacuumRequestWork(AVW_BRINSummarizeRange,
+ RelationGetRelid(idxRel),
+ lastPageRange);
+ brin_free_tuple(lastPageTuple);
+ }
+
+ brtup = brinGetTupleForHeapBlock(revmap, heapBlk, &buf, &off,
+ NULL, BUFFER_LOCK_SHARE, NULL);
/* if range is unsummarized, there's nothing to do */
if (!brtup)
brin_vacuum_scan(info->index, info->strategy);
- brinsummarize(info->index, heapRel,
+ brinsummarize(info->index, heapRel, BRIN_ALL_BLOCKRANGES,
&stats->num_index_tuples, &stats->num_index_tuples);
heap_close(heapRel, AccessShareLock);
BrinOptions *rdopts;
int numoptions;
static const relopt_parse_elt tab[] = {
- {"pages_per_range", RELOPT_TYPE_INT, offsetof(BrinOptions, pagesPerRange)}
+ {"pages_per_range", RELOPT_TYPE_INT, offsetof(BrinOptions, pagesPerRange)},
+ {"autosummarize", RELOPT_TYPE_BOOL, offsetof(BrinOptions, autosummarize)}
};
options = parseRelOptions(reloptions, validate, RELOPT_KIND_BRIN,
*/
Datum
brin_summarize_new_values(PG_FUNCTION_ARGS)
+{
+ Datum relation = PG_GETARG_DATUM(0);
+
+ return DirectFunctionCall2(brin_summarize_range,
+ relation,
+ Int64GetDatum((int64) BRIN_ALL_BLOCKRANGES));
+}
+
+/*
+ * SQL-callable function to summarize the indicated page range, if not already
+ * summarized. If the second argument is BRIN_ALL_BLOCKRANGES, all
+ * unsummarized ranges are summarized.
+ */
+Datum
+brin_summarize_range(PG_FUNCTION_ARGS)
{
Oid indexoid = PG_GETARG_OID(0);
+ int64 heapBlk64 = PG_GETARG_INT64(1);
+ BlockNumber heapBlk;
Oid heapoid;
Relation indexRel;
Relation heapRel;
double numSummarized = 0;
+ if (heapBlk64 > BRIN_ALL_BLOCKRANGES || heapBlk64 < 0)
+ {
+ char *blk = psprintf(INT64_FORMAT, heapBlk64);
+
+ ereport(ERROR,
+ (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+ errmsg("block number out of range: %s", blk)));
+ }
+ heapBlk = (BlockNumber) heapBlk64;
+
/*
* We must lock table before index to avoid deadlocks. However, if the
* passed indexoid isn't an index then IndexGetRelation() will fail.
RelationGetRelationName(indexRel))));
/* OK, do it */
- brinsummarize(indexRel, heapRel, &numSummarized, NULL);
+ brinsummarize(indexRel, heapRel, heapBlk, &numSummarized, NULL);
relation_close(indexRel, ShareUpdateExclusiveLock);
relation_close(heapRel, ShareUpdateExclusiveLock);
}
/*
- * Scan a complete BRIN index, and summarize each page range that's not already
- * summarized. The index and heap must have been locked by caller in at
- * least ShareUpdateExclusiveLock mode.
+ * Summarize page ranges that are not already summarized. If pageRange is
+ * BRIN_ALL_BLOCKRANGES then the whole table is scanned; otherwise, only the
+ * page range containing the given heap page number is scanned.
*
* For each new index tuple inserted, *numSummarized (if not NULL) is
* incremented; for each existing tuple, *numExisting (if not NULL) is
* incremented.
*/
static void
-brinsummarize(Relation index, Relation heapRel, double *numSummarized,
- double *numExisting)
+brinsummarize(Relation index, Relation heapRel, BlockNumber pageRange,
+ double *numSummarized, double *numExisting)
{
BrinRevmap *revmap;
BrinBuildState *state = NULL;
BlockNumber heapBlk;
BlockNumber pagesPerRange;
Buffer buf;
+ BlockNumber startBlk;
+ BlockNumber endBlk;
+
+ /* determine range of pages to process; nothing to do for an empty table */
+ heapNumBlocks = RelationGetNumberOfBlocks(heapRel);
+ if (heapNumBlocks == 0)
+ return;
revmap = brinRevmapInitialize(index, &pagesPerRange, NULL);
+ if (pageRange == BRIN_ALL_BLOCKRANGES)
+ {
+ startBlk = 0;
+ endBlk = heapNumBlocks;
+ }
+ else
+ {
+ startBlk = (pageRange / pagesPerRange) * pagesPerRange;
+ /* Nothing to do if start point is beyond end of table */
+ if (startBlk > heapNumBlocks)
+ {
+ brinRevmapTerminate(revmap);
+ return;
+ }
+ endBlk = startBlk + pagesPerRange;
+ if (endBlk > heapNumBlocks)
+ endBlk = heapNumBlocks;
+ }
+
/*
* Scan the revmap to find unsummarized items.
*/
buf = InvalidBuffer;
- heapNumBlocks = RelationGetNumberOfBlocks(heapRel);
- for (heapBlk = 0; heapBlk < heapNumBlocks; heapBlk += pagesPerRange)
+ for (heapBlk = startBlk; heapBlk < endBlk; heapBlk += pagesPerRange)
{
BrinTuple *tup;
OffsetNumber off;
#include "storage/procsignal.h"
#include "storage/sinvaladt.h"
#include "tcop/tcopprot.h"
+#include "utils/dsa.h"
#include "utils/fmgroids.h"
+#include "utils/fmgrprotos.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/ps_status.h"
* av_runningWorkers the WorkerInfo non-free queue
* av_startingWorker pointer to WorkerInfo currently being started (cleared by
* the worker itself as soon as it's up and running)
+ * av_dsa_handle handle for allocatable shared memory
*
* This struct is protected by AutovacuumLock, except for av_signal and parts
- * of the worker list (see above).
+ * of the worker list (see above). av_dsa_handle is readable unlocked.
*-------------
*/
typedef struct
dlist_head av_freeWorkers;
dlist_head av_runningWorkers;
WorkerInfo av_startingWorker;
+ dsa_handle av_dsa_handle;
+ dsa_pointer av_workitems;
} AutoVacuumShmemStruct;
static AutoVacuumShmemStruct *AutoVacuumShmem;
/* Pointer to my own WorkerInfo, valid on each worker */
static WorkerInfo MyWorkerInfo = NULL;
+/*
+ * Autovacuum workitem array, stored in AutoVacuumShmem->av_workitems. This
+ * list is mostly protected by AutovacuumLock, except that if it's marked
+ * 'active' other processes must not modify the work-identifying members,
+ * though changing the list pointers is okay.
+ */
+typedef struct AutoVacuumWorkItem
+{
+ AutoVacuumWorkItemType avw_type;
+ Oid avw_database;
+ Oid avw_relation;
+ BlockNumber avw_blockNumber;
+ bool avw_active;
+ dsa_pointer avw_next; /* doubly linked list pointers */
+ dsa_pointer avw_prev;
+} AutoVacuumWorkItem;
+
+#define NUM_WORKITEMS 256
+typedef struct
+{
+ dsa_pointer avs_usedItems;
+ dsa_pointer avs_freeItems;
+} AutovacWorkItems;
+
+static dsa_area *AutoVacuumDSA = NULL;
+
/* PID of launcher, valid only in worker while shutting down */
int AutovacuumLauncherPid = 0;
static PgStat_StatTabEntry *get_pgstat_tabentry_relid(Oid relid, bool isshared,
PgStat_StatDBEntry *shared,
PgStat_StatDBEntry *dbentry);
+static void perform_work_item(AutoVacuumWorkItem *workitem);
static void autovac_report_activity(autovac_table *tab);
+static void autovac_report_workitem(AutoVacuumWorkItem *workitem,
+ const char *nspname, const char *relname);
static void av_sighup_handler(SIGNAL_ARGS);
static void avl_sigusr2_handler(SIGNAL_ARGS);
static void avl_sigterm_handler(SIGNAL_ARGS);
static void autovac_refresh_stats(void);
+static void remove_wi_from_list(dsa_pointer *list, dsa_pointer wi_ptr);
+static void add_wi_to_list(dsa_pointer *list, dsa_pointer wi_ptr);
*/
rebuild_database_list(InvalidOid);
+ /*
+ * Set up our DSA so that backends can install work-item requests. It may
+ * already exist as created by a previous launcher.
+ */
+ if (!AutoVacuumShmem->av_dsa_handle)
+ {
+ LWLockAcquire(AutovacuumLock, LW_EXCLUSIVE);
+ AutoVacuumDSA = dsa_create(AutovacuumLock->tranche);
+ /* make sure it doesn't go away even if we do */
+ dsa_pin(AutoVacuumDSA);
+ dsa_pin_mapping(AutoVacuumDSA);
+ AutoVacuumShmem->av_dsa_handle = dsa_get_handle(AutoVacuumDSA);
+ /* delay array allocation until first request */
+ AutoVacuumShmem->av_workitems = InvalidDsaPointer;
+ LWLockRelease(AutovacuumLock);
+ }
+ else
+ {
+ AutoVacuumDSA = dsa_attach(AutoVacuumShmem->av_dsa_handle);
+ dsa_pin_mapping(AutoVacuumDSA);
+ }
+
/* loop until shutdown request */
while (!got_SIGTERM)
{
{
char dbname[NAMEDATALEN];
+ if (AutoVacuumShmem->av_dsa_handle)
+ {
+ /* First use of DSA in this worker, so attach to it */
+ Assert(!AutoVacuumDSA);
+ AutoVacuumDSA = dsa_attach(AutoVacuumShmem->av_dsa_handle);
+ dsa_pin_mapping(AutoVacuumDSA);
+ }
+
/*
* Report autovac startup to the stats collector. We deliberately do
* this before InitPostgres, so that the last_autovac_time will get
VacuumCostLimit = stdVacuumCostLimit;
}
+ /*
+ * Perform additional work items, as requested by backends.
+ */
+ if (AutoVacuumShmem->av_workitems)
+ {
+ dsa_pointer wi_ptr;
+ AutovacWorkItems *workitems;
+
+ LWLockAcquire(AutovacuumLock, LW_EXCLUSIVE);
+
+ /*
+ * Scan the list of pending items, and process the inactive ones in
+ * our database.
+ */
+ workitems = (AutovacWorkItems *)
+ dsa_get_address(AutoVacuumDSA, AutoVacuumShmem->av_workitems);
+ wi_ptr = workitems->avs_usedItems;
+
+ while (wi_ptr != InvalidDsaPointer)
+ {
+ AutoVacuumWorkItem *workitem;
+
+ workitem = (AutoVacuumWorkItem *)
+ dsa_get_address(AutoVacuumDSA, wi_ptr);
+
+ if (workitem->avw_database == MyDatabaseId && !workitem->avw_active)
+ {
+ dsa_pointer next_ptr;
+
+ /* claim this one */
+ workitem->avw_active = true;
+
+ LWLockRelease(AutovacuumLock);
+
+ perform_work_item(workitem);
+
+ /*
+ * Check for config changes before acquiring lock for further
+ * jobs.
+ */
+ CHECK_FOR_INTERRUPTS();
+ if (got_SIGHUP)
+ {
+ got_SIGHUP = false;
+ ProcessConfigFile(PGC_SIGHUP);
+ }
+
+ LWLockAcquire(AutovacuumLock, LW_EXCLUSIVE);
+
+ /* Put the array item back for the next user */
+ next_ptr = workitem->avw_next;
+ remove_wi_from_list(&workitems->avs_usedItems, wi_ptr);
+ add_wi_to_list(&workitems->avs_freeItems, wi_ptr);
+ wi_ptr = next_ptr;
+ }
+ else
+ wi_ptr = workitem->avw_next;
+ }
+
+ /* all done */
+ LWLockRelease(AutovacuumLock);
+ }
+
/*
* We leak table_toast_map here (among other things), but since we're
* going away soon, it's not a problem.
CommitTransactionCommand();
}
+/*
+ * Execute a previously registered work item.
+ */
+static void
+perform_work_item(AutoVacuumWorkItem *workitem)
+{
+ char *cur_datname = NULL;
+ char *cur_nspname = NULL;
+ char *cur_relname = NULL;
+
+ /*
+ * Note we do not store table info in MyWorkerInfo, since this is not
+ * vacuuming proper.
+ */
+
+ /*
+ * Save the relation name for a possible error message, to avoid a catalog
+ * lookup in case of an error. If any of these return NULL, then the
+ * relation has been dropped since last we checked; skip it. Note: they
+ * must live in a long-lived memory context because we call vacuum and
+ * analyze in different transactions.
+ */
+
+ cur_relname = get_rel_name(workitem->avw_relation);
+ cur_nspname = get_namespace_name(get_rel_namespace(workitem->avw_relation));
+ cur_datname = get_database_name(MyDatabaseId);
+ if (!cur_relname || !cur_nspname || !cur_datname)
+ goto deleted2;
+
+ autovac_report_workitem(workitem, cur_nspname, cur_datname);
+
+ /*
+ * We will abort the current work item if something errors out, and
+ * continue with the next one; in particular, this happens if we are
+ * interrupted with SIGINT. Note that this means that the work item list
+ * can be lossy.
+ */
+ PG_TRY();
+ {
+ /* have at it */
+ MemoryContextSwitchTo(TopTransactionContext);
+
+ switch (workitem->avw_type)
+ {
+ case AVW_BRINSummarizeRange:
+ DirectFunctionCall2(brin_summarize_range,
+ ObjectIdGetDatum(workitem->avw_relation),
+ Int64GetDatum((int64) workitem->avw_blockNumber));
+ break;
+ default:
+ elog(WARNING, "unrecognized work item found: type %d",
+ workitem->avw_type);
+ break;
+ }
+
+ /*
+ * Clear a possible query-cancel signal, to avoid a late reaction to
+ * an automatically-sent signal because of vacuuming the current table
+ * (we're done with it, so it would make no sense to cancel at this
+ * point.)
+ */
+ QueryCancelPending = false;
+ }
+ PG_CATCH();
+ {
+ /*
+ * Abort the transaction, start a new one, and proceed with the next
+ * table in our list.
+ */
+ HOLD_INTERRUPTS();
+ errcontext("processing work entry for relation \"%s.%s.%s\"",
+ cur_datname, cur_nspname, cur_relname);
+ EmitErrorReport();
+
+ /* this resets the PGXACT flags too */
+ AbortOutOfAnyTransaction();
+ FlushErrorState();
+ MemoryContextResetAndDeleteChildren(PortalContext);
+
+ /* restart our transaction for the following operations */
+ StartTransactionCommand();
+ RESUME_INTERRUPTS();
+ }
+ PG_END_TRY();
+
+ /* We intentionally do not set did_vacuum here */
+
+ /* be tidy */
+deleted2:
+ if (cur_datname)
+ pfree(cur_datname);
+ if (cur_nspname)
+ pfree(cur_nspname);
+ if (cur_relname)
+ pfree(cur_relname);
+}
+
/*
* extract_autovac_opts
*
pgstat_report_activity(STATE_RUNNING, activity);
}
+/*
+ * autovac_report_workitem
+ * Report to pgstat that autovacuum is processing a work item
+ */
+static void
+autovac_report_workitem(AutoVacuumWorkItem *workitem,
+ const char *nspname, const char *relname)
+{
+ char activity[MAX_AUTOVAC_ACTIV_LEN + 12 + 2];
+ char blk[12 + 2];
+ int len;
+
+ switch (workitem->avw_type)
+ {
+ case AVW_BRINSummarizeRange:
+ snprintf(activity, MAX_AUTOVAC_ACTIV_LEN,
+ "autovacuum: BRIN summarize");
+ break;
+ }
+
+ /*
+ * Report the qualified name of the relation, and the block number if any
+ */
+ len = strlen(activity);
+
+ if (BlockNumberIsValid(workitem->avw_blockNumber))
+ snprintf(blk, sizeof(blk), " %u", workitem->avw_blockNumber);
+ else
+ blk[0] = '\0';
+
+ snprintf(activity + len, MAX_AUTOVAC_ACTIV_LEN - len,
+ " %s.%s%s", nspname, relname, blk);
+
+ /* Set statement_timestamp() to current time for pg_stat_activity */
+ SetCurrentStatementStartTimestamp();
+
+ pgstat_report_activity(STATE_RUNNING, activity);
+}
+
/*
* AutoVacuumingActive
* Check GUC vars and report whether the autovacuum process should be
return true;
}
+/*
+ * Request one work item to the next autovacuum run processing our database.
+ */
+void
+AutoVacuumRequestWork(AutoVacuumWorkItemType type, Oid relationId,
+ BlockNumber blkno)
+{
+ AutovacWorkItems *workitems;
+ dsa_pointer wi_ptr;
+ AutoVacuumWorkItem *workitem;
+
+ LWLockAcquire(AutovacuumLock, LW_EXCLUSIVE);
+
+ /*
+ * It may be useful to de-duplicate the list upon insertion. For the only
+ * currently existing caller, this is not necessary.
+ */
+
+ /* First use in this process? Set up DSA */
+ if (!AutoVacuumDSA)
+ {
+ if (!AutoVacuumShmem->av_dsa_handle)
+ {
+ /* autovacuum launcher not started; nothing can be done */
+ LWLockRelease(AutovacuumLock);
+ return;
+ }
+ AutoVacuumDSA = dsa_attach(AutoVacuumShmem->av_dsa_handle);
+ dsa_pin_mapping(AutoVacuumDSA);
+ }
+
+ /* First use overall? Allocate work items array */
+ if (AutoVacuumShmem->av_workitems == InvalidDsaPointer)
+ {
+ int i;
+ AutovacWorkItems *workitems;
+
+ AutoVacuumShmem->av_workitems =
+ dsa_allocate_extended(AutoVacuumDSA,
+ sizeof(AutovacWorkItems) +
+ NUM_WORKITEMS * sizeof(AutoVacuumWorkItem),
+ DSA_ALLOC_NO_OOM);
+ /* if out of memory, silently disregard the request */
+ if (AutoVacuumShmem->av_workitems == InvalidDsaPointer)
+ {
+ LWLockRelease(AutovacuumLock);
+ dsa_detach(AutoVacuumDSA);
+ AutoVacuumDSA = NULL;
+ return;
+ }
+
+ /* Initialize each array entry as a member of the free list */
+ workitems = dsa_get_address(AutoVacuumDSA, AutoVacuumShmem->av_workitems);
+
+ workitems->avs_usedItems = InvalidDsaPointer;
+ workitems->avs_freeItems = InvalidDsaPointer;
+ for (i = 0; i < NUM_WORKITEMS; i++)
+ {
+ /* XXX surely there is a simpler way to do this */
+ wi_ptr = AutoVacuumShmem->av_workitems + sizeof(AutovacWorkItems) +
+ sizeof(AutoVacuumWorkItem) * i;
+ workitem = (AutoVacuumWorkItem *) dsa_get_address(AutoVacuumDSA, wi_ptr);
+
+ workitem->avw_type = 0;
+ workitem->avw_database = InvalidOid;
+ workitem->avw_relation = InvalidOid;
+ workitem->avw_active = false;
+
+ /* put this item in the free list */
+ workitem->avw_next = workitems->avs_freeItems;
+ workitems->avs_freeItems = wi_ptr;
+ }
+ }
+
+ workitems = (AutovacWorkItems *)
+ dsa_get_address(AutoVacuumDSA, AutoVacuumShmem->av_workitems);
+
+ /* If array is full, disregard the request */
+ if (workitems->avs_freeItems == InvalidDsaPointer)
+ {
+ LWLockRelease(AutovacuumLock);
+ dsa_detach(AutoVacuumDSA);
+ AutoVacuumDSA = NULL;
+ return;
+ }
+
+ /* remove workitem struct from free list ... */
+ wi_ptr = workitems->avs_freeItems;
+ remove_wi_from_list(&workitems->avs_freeItems, wi_ptr);
+
+ /* ... initialize it ... */
+ workitem = dsa_get_address(AutoVacuumDSA, wi_ptr);
+ workitem->avw_type = type;
+ workitem->avw_database = MyDatabaseId;
+ workitem->avw_relation = relationId;
+ workitem->avw_blockNumber = blkno;
+ workitem->avw_active = false;
+
+ /* ... and put it on autovacuum's to-do list */
+ add_wi_to_list(&workitems->avs_usedItems, wi_ptr);
+
+ LWLockRelease(AutovacuumLock);
+
+ dsa_detach(AutoVacuumDSA);
+ AutoVacuumDSA = NULL;
+}
+
/*
* autovac_init
* This is called at postmaster initialization.
pgstat_clear_snapshot();
}
+
+/*
+ * Simplistic open-coded list implementation for objects stored in DSA.
+ * Each item is doubly linked, but we have no tail pointer, and the "prev"
+ * element of the first item is null, not the list.
+ */
+
+/*
+ * Remove a work item from the given list.
+ */
+static void
+remove_wi_from_list(dsa_pointer *list, dsa_pointer wi_ptr)
+{
+ AutoVacuumWorkItem *workitem = dsa_get_address(AutoVacuumDSA, wi_ptr);
+ dsa_pointer next = workitem->avw_next;
+ dsa_pointer prev = workitem->avw_prev;
+
+ workitem->avw_next = workitem->avw_prev = InvalidDsaPointer;
+
+ if (next != InvalidDsaPointer)
+ {
+ workitem = dsa_get_address(AutoVacuumDSA, next);
+ workitem->avw_prev = prev;
+ }
+
+ if (prev != InvalidDsaPointer)
+ {
+ workitem = dsa_get_address(AutoVacuumDSA, prev);
+ workitem->avw_next = next;
+ }
+ else
+ *list = next;
+}
+
+/*
+ * Add a workitem to the given list
+ */
+static void
+add_wi_to_list(dsa_pointer *list, dsa_pointer wi_ptr)
+{
+ if (*list == InvalidDsaPointer)
+ {
+ /* list is empty; item is now singleton */
+ *list = wi_ptr;
+ }
+ else
+ {
+ AutoVacuumWorkItem *workitem = dsa_get_address(AutoVacuumDSA, wi_ptr);
+ AutoVacuumWorkItem *old = dsa_get_address(AutoVacuumDSA, *list);
+
+ /* Put item at head of list */
+ workitem->avw_next = *list;
+ old->avw_prev = wi_ptr;
+ *list = wi_ptr;
+ }
+}
projects / postgresql.git / commitdiff