citus/src/include/distributed/resource_lock.h

105 lines
3.8 KiB
C

/*-------------------------------------------------------------------------
*
* resource_lock.h
* Locking Infrastructure for Citus.
*
* Copyright (c) 2012-2016, Citus Data, Inc.
*-------------------------------------------------------------------------
*/
#ifndef RESOURCE_LOCK_H
#define RESOURCE_LOCK_H
#include "postgres.h" /* IWYU pragma: keep */
#include "c.h"
#include "distributed/worker_transaction.h"
#include "nodes/pg_list.h"
#include "storage/lock.h"
/*
* Postgres' advisory locks use 'field4' to discern between different kind of
* advisory locks. Only 1 and 2 are used allowing us to define non-conflicting
* lock methods.
*
* In case postgres starts to use additional values, Citus's values
* will have to be changed. That just requires re-compiling and a restart.
*/
typedef enum AdvisoryLocktagClass
{
/* values defined in postgres' lockfuncs.c */
ADV_LOCKTAG_CLASS_INT64 = 1,
ADV_LOCKTAG_CLASS_INT32 = 2,
/* Citus lock types */
ADV_LOCKTAG_CLASS_CITUS_SHARD_METADATA = 4,
ADV_LOCKTAG_CLASS_CITUS_SHARD = 5,
ADV_LOCKTAG_CLASS_CITUS_JOB = 6
} AdvisoryLocktagClass;
/* reuse advisory lock, but with different, unused field 4 (4)*/
#define SET_LOCKTAG_SHARD_METADATA_RESOURCE(tag, db, shardid) \
SET_LOCKTAG_ADVISORY(tag, \
db, \
(uint32) ((shardid) >> 32), \
(uint32) (shardid), \
ADV_LOCKTAG_CLASS_CITUS_SHARD_METADATA)
/* reuse advisory lock, but with different, unused field 4 (5)*/
#define SET_LOCKTAG_SHARD_RESOURCE(tag, db, shardid) \
SET_LOCKTAG_ADVISORY(tag, \
db, \
(uint32) ((shardid) >> 32), \
(uint32) (shardid), \
ADV_LOCKTAG_CLASS_CITUS_SHARD)
/* reuse advisory lock, but with different, unused field 4 (6) */
#define SET_LOCKTAG_JOB_RESOURCE(tag, db, jobid) \
SET_LOCKTAG_ADVISORY(tag, \
db, \
(uint32) ((jobid) >> 32), \
(uint32) (jobid), \
ADV_LOCKTAG_CLASS_CITUS_JOB)
/* Lock shard/relation metadata for safe modifications */
extern void LockShardDistributionMetadata(int64 shardId, LOCKMODE lockMode);
extern bool TryLockShardDistributionMetadata(int64 shardId, LOCKMODE lockMode);
extern void LockShardListMetadataOnWorkers(LOCKMODE lockmode, List *shardIntervalList);
extern void BlockWritesToShardList(List *shardList);
/* Lock shard/relation metadata of the referenced reference table if exists */
extern void LockReferencedReferenceShardDistributionMetadata(uint64 shardId, LOCKMODE
lock);
/* Lock shard data, for DML commands or remote fetches */
extern void LockShardResource(uint64 shardId, LOCKMODE lockmode);
extern void UnlockShardResource(uint64 shardId, LOCKMODE lockmode);
/* Lock a job schema or partition task directory */
extern void LockJobResource(uint64 jobId, LOCKMODE lockmode);
extern void UnlockJobResource(uint64 jobId, LOCKMODE lockmode);
/* Lock multiple shards for safe modification */
extern void LockShardListMetadata(List *shardIntervalList, LOCKMODE lockMode);
extern void LockShardsInPlacementListMetadata(List *shardPlacementList,
LOCKMODE lockMode);
extern void SerializeNonCommutativeWrites(List *shardIntervalList, LOCKMODE lockMode);
extern void LockRelationShardResources(List *relationShardList, LOCKMODE lockMode);
extern List * GetSortedReferenceShardIntervals(List *relationList);
/* Lock partitions of partitioned table */
extern void LockPartitionsInRelationList(List *relationIdList, LOCKMODE lockmode);
extern void LockPartitionRelations(Oid relationId, LOCKMODE lockMode);
/* Lock parent table's colocated shard resource */
extern void LockParentShardResourceIfPartition(uint64 shardId, LOCKMODE lockMode);
/* Lock mode translation between text and enum */
extern LOCKMODE LockModeTextToLockMode(const char *lockModeName);
extern const char * LockModeToLockModeText(LOCKMODE lockMode);
#endif /* RESOURCE_LOCK_H */