src/include/storage/predicate.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * predicate.h
   4  *        POSTGRES public predicate locking definitions.
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * src/include/storage/predicate.h
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef PREDICATE_H
  15 #define PREDICATE_H
  16
  17 #include "storage/lock.h"
  18 #include "utils/relcache.h"
  19 #include "utils/snapshot.h"
  20
  21
  22 /*
  23  * GUC variables
  24  */
  25 extern int      max_predicate_locks_per_xact;
  26 extern int      max_predicate_locks_per_relation;
  27 extern int      max_predicate_locks_per_page;
  28
  29
  30 /* Number of SLRU buffers to use for Serial SLRU */
  31 #define NUM_SERIAL_BUFFERS              16
  32
  33 /*
  34  * A handle used for sharing SERIALIZABLEXACT objects between the participants
  35  * in a parallel query.
  36  */
  37 typedef void *SerializableXactHandle;
  38
  39 /*
  40  * function prototypes
  41  */
  42
  43 /* housekeeping for shared memory predicate lock structures */
  44 extern void InitPredicateLocks(void);
  45 extern Size PredicateLockShmemSize(void);
  46
  47 extern void CheckPointPredicate(void);
  48
  49 /* predicate lock reporting */
  50 extern bool PageIsPredicateLocked(Relation relation, BlockNumber blkno);
  51
  52 /* predicate lock maintenance */
  53 extern Snapshot GetSerializableTransactionSnapshot(Snapshot snapshot);
  54 extern void SetSerializableTransactionSnapshot(Snapshot snapshot,
  55                                                                                            VirtualTransactionId *sourcevxid,
  56                                                                                            int sourcepid);
  57 extern void RegisterPredicateLockingXid(TransactionId xid);
  58 extern void PredicateLockRelation(Relation relation, Snapshot snapshot);
  59 extern void PredicateLockPage(Relation relation, BlockNumber blkno, Snapshot snapshot);
  60 extern void PredicateLockTID(Relation relation, ItemPointer tid, Snapshot snapshot,
  61                                                          TransactionId insert_xid);
  62 extern void PredicateLockPageSplit(Relation relation, BlockNumber oldblkno, BlockNumber newblkno);
  63 extern void PredicateLockPageCombine(Relation relation, BlockNumber oldblkno, BlockNumber newblkno);
  64 extern void TransferPredicateLocksToHeapRelation(Relation relation);
  65 extern void ReleasePredicateLocks(bool isCommit, bool isReadOnlySafe);
  66
  67 /* conflict detection (may also trigger rollback) */
  68 extern bool CheckForSerializableConflictOutNeeded(Relation relation, Snapshot snapshot);
  69 extern void CheckForSerializableConflictOut(Relation relation, TransactionId xid, Snapshot snapshot);
  70 extern void CheckForSerializableConflictIn(Relation relation, ItemPointer tid, BlockNumber blkno);
  71 extern void CheckTableForSerializableConflictIn(Relation relation);
  72
  73 /* final rollback checking */
  74 extern void PreCommit_CheckForSerializationFailure(void);
  75
  76 /* two-phase commit support */
  77 extern void AtPrepare_PredicateLocks(void);
  78 extern void PostPrepare_PredicateLocks(TransactionId xid);
  79 extern void PredicateLockTwoPhaseFinish(TransactionId xid, bool isCommit);
  80 extern void predicatelock_twophase_recover(TransactionId xid, uint16 info,
  81                                                                                    void *recdata, uint32 len);
  82
  83 /* parallel query support */
  84 extern SerializableXactHandle ShareSerializableXact(void);
  85 extern void AttachSerializableXact(SerializableXactHandle handle);
  86
  87 #endif                                                  /* PREDICATE_H */