+++ /dev/null
-/*-------------------------------------------------------------------------
- *
- * multi.c
- * multi level lock table manager
- *
- * Standard multi-level lock manager as per the Gray paper
- * (at least, that is what it is supposed to be). We implement
- * three levels -- RELN, PAGE, TUPLE. Tuple is actually TID
- * a physical record pointer. It isn't an object id.
- *
- * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *
- * IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/storage/lmgr/Attic/multi.c,v 1.34 2000/01/26 05:57:02 momjian Exp $
- *
- * NOTES:
- * (1) The lock.c module assumes that the caller here is doing
- * two phase locking.
- *
- *-------------------------------------------------------------------------
- */
-#include "postgres.h"
-
-#include "miscadmin.h"
-#include "storage/lmgr.h"
-#include "storage/multilev.h"
-#include "utils/rel.h"
-
-static bool MultiAcquire(LOCKMETHOD lockmethod, LOCKTAG *tag,
- LOCKMODE lockmode, PG_LOCK_LEVEL level);
-static bool MultiRelease(LOCKMETHOD lockmethod, LOCKTAG *tag,
- LOCKMODE lockmode, PG_LOCK_LEVEL level);
-
-/*
- * INTENT indicates to higher level that a lower level lock has been
- * set. For example, a write lock on a tuple conflicts with a write
- * lock on a relation. This conflict is detected as a WRITE_INTENT/
- * WRITE conflict between the tuple's intent lock and the relation's
- * write lock.
- */
-static LOCKMASK MultiConflicts[] = {
- (int) NULL,
- /* All reads and writes at any level conflict with a write lock */
- (1 << WRITE_LOCK) | (1 << WRITE_INTENT) | (1 << READ_LOCK) | (1 << READ_INTENT),
- /* read locks conflict with write locks at curr and lower levels */
- (1 << WRITE_LOCK) | (1 << WRITE_INTENT),
- /* write intent locks */
- (1 << READ_LOCK) | (1 << WRITE_LOCK),
- /* read intent locks */
- (1 << WRITE_LOCK),
-
- /*
- * extend locks for archive storage manager conflict only w/extend
- * locks
- */
- (1 << EXTEND_LOCK)
-};
-
-/*
- * write locks have higher priority than read locks and extend locks. May
- * want to treat INTENT locks differently.
- */
-static int MultiPrios[] = {
- (int) NULL,
- 2,
- 1,
- 2,
- 1,
- 1
-};
-
-/*
- * Lock table identifier for this lock table. The multi-level
- * lock table is ONE lock table, not three.
- */
-LOCKMETHOD MultiTableId = (LOCKMETHOD) NULL;
-LOCKMETHOD LongTermTableId = (LOCKMETHOD) NULL;
-
-#ifdef NOT_USED
-LOCKMETHOD ShortTermTableId = (LOCKMETHOD) NULL;
-
-#endif
-
-/*
- * Create the lock table described by MultiConflicts and Multiprio.
- */
-LOCKMETHOD
-InitMultiLevelLocks()
-{
- int lockmethod;
-
- lockmethod = LockMethodTableInit("MultiLevelLockTable",
- MultiConflicts, MultiPrios, MAX_LOCKMODES - 1);
- MultiTableId = lockmethod;
- if (!(MultiTableId))
- elog(ERROR, "InitMultiLocks: couldnt initialize lock table");
- /* -----------------------
- * No short term lock table for now. -Jeff 15 July 1991
- *
- * ShortTermTableId = LockMethodTableRename(lockmethod);
- * if (! (ShortTermTableId)) {
- * elog(ERROR,"InitMultiLocks: couldnt rename lock table");
- * }
- * -----------------------
- */
-
-#ifdef USER_LOCKS
-
- /*
- * Allocate another tableId for long-term locks
- */
- LongTermTableId = LockMethodTableRename(MultiTableId);
- if (!(LongTermTableId))
- {
- elog(ERROR,
- "InitMultiLevelLocks: couldn't rename long-term lock table");
- }
-#endif
-
- return MultiTableId;
-}
-
-/*
- * MultiLockReln -- lock a relation
- *
- * Returns: TRUE if the lock can be set, FALSE otherwise.
- */
-bool
-MultiLockReln(LockInfo lockinfo, LOCKMODE lockmode)
-{
- LOCKTAG tag;
-
- /*
- * LOCKTAG has two bytes of padding, unfortunately. The hash function
- * will return miss if the padding bytes aren't zero'd.
- */
- MemSet(&tag, 0, sizeof(tag));
- tag.relId = lockinfo->lockRelId.relId;
- tag.dbId = lockinfo->lockRelId.dbId;
- return MultiAcquire(MultiTableId, &tag, lockmode, RELN_LEVEL);
-}
-
-#ifdef NOT_USED
-/*
- * MultiLockTuple -- Lock the TID associated with a tuple
- *
- * Returns: TRUE if lock is set, FALSE otherwise.
- *
- * Side Effects: causes intention level locks to be set
- * at the page and relation level.
- */
-bool
-MultiLockTuple(LockInfo lockinfo, ItemPointer tidPtr, LOCKMODE lockmode)
-{
- LOCKTAG tag;
-
- /*
- * LOCKTAG has two bytes of padding, unfortunately. The hash function
- * will return miss if the padding bytes aren't zero'd.
- */
- MemSet(&tag, 0, sizeof(tag));
-
- tag.relId = lockinfo->lockRelId.relId;
- tag.dbId = lockinfo->lockRelId.dbId;
-
- /* not locking any valid Tuple, just the page */
- tag.tupleId = *tidPtr;
- return MultiAcquire(MultiTableId, &tag, lockmode, TUPLE_LEVEL);
-}
-
-#endif
-
-/*
- * same as above at page level
- */
-bool
-MultiLockPage(LockInfo lockinfo, ItemPointer tidPtr, LOCKMODE lockmode)
-{
- LOCKTAG tag;
-
- /*
- * LOCKTAG has two bytes of padding, unfortunately. The hash function
- * will return miss if the padding bytes aren't zero'd.
- */
- MemSet(&tag, 0, sizeof(tag));
-
-
- /* ----------------------------
- * Now we want to set the page offset to be invalid
- * and lock the block. There is some confusion here as to what
- * a page is. In Postgres a page is an 8k block, however this
- * block may be partitioned into many subpages which are sometimes
- * also called pages. The term is overloaded, so don't be fooled
- * when we say lock the page we mean the 8k block. -Jeff 16 July 1991
- * ----------------------------
- */
- tag.relId = lockinfo->lockRelId.relId;
- tag.dbId = lockinfo->lockRelId.dbId;
- BlockIdCopy(&(tag.tupleId.ip_blkid), &(tidPtr->ip_blkid));
- return MultiAcquire(MultiTableId, &tag, lockmode, PAGE_LEVEL);
-}
-
-/*
- * MultiAcquire -- acquire multi level lock at requested level
- *
- * Returns: TRUE if lock is set, FALSE if not
- * Side Effects:
- */
-static bool
-MultiAcquire(LOCKMETHOD lockmethod,
- LOCKTAG *tag,
- LOCKMODE lockmode,
- PG_LOCK_LEVEL level)
-{
- LOCKMODE locks[N_LEVELS];
- int i,
- status;
- LOCKTAG xxTag,
- *tmpTag = &xxTag;
- int retStatus = TRUE;
-
- /*
- * Three levels implemented. If we set a low level (e.g. Tuple) lock,
- * we must set INTENT locks on the higher levels. The intent lock
- * detects conflicts between the low level lock and an existing high
- * level lock. For example, setting a write lock on a tuple in a
- * relation is disallowed if there is an existing read lock on the
- * entire relation. The write lock would set a WRITE + INTENT lock on
- * the relation and that lock would conflict with the read.
- */
- switch (level)
- {
- case RELN_LEVEL:
- locks[0] = lockmode;
- locks[1] = NO_LOCK;
- locks[2] = NO_LOCK;
- break;
- case PAGE_LEVEL:
- locks[0] = lockmode + INTENT;
- locks[1] = lockmode;
- locks[2] = NO_LOCK;
- break;
- case TUPLE_LEVEL:
- locks[0] = lockmode + INTENT;
- locks[1] = lockmode + INTENT;
- locks[2] = lockmode;
- break;
- default:
- elog(ERROR, "MultiAcquire: bad lock level");
- return FALSE;
- }
-
- /*
- * construct a new tag as we go. Always loop through all levels, but
- * if we arent' seting a low level lock, locks[i] is set to NO_LOCK
- * for the lower levels. Always start from the highest level and go
- * to the lowest level.
- */
- MemSet(tmpTag, 0, sizeof(*tmpTag));
- tmpTag->relId = tag->relId;
- tmpTag->dbId = tag->dbId;
-
- for (i = 0; i < N_LEVELS; i++)
- {
- if (locks[i] != NO_LOCK)
- {
- switch (i)
- {
- case RELN_LEVEL:
- /* -------------
- * Set the block # and offset to invalid
- * -------------
- */
- BlockIdSet(&(tmpTag->tupleId.ip_blkid), InvalidBlockNumber);
- tmpTag->tupleId.ip_posid = InvalidOffsetNumber;
- break;
- case PAGE_LEVEL:
- /* -------------
- * Copy the block #, set the offset to invalid
- * -------------
- */
- BlockIdCopy(&(tmpTag->tupleId.ip_blkid),
- &(tag->tupleId.ip_blkid));
- tmpTag->tupleId.ip_posid = InvalidOffsetNumber;
- break;
- case TUPLE_LEVEL:
- /* --------------
- * Copy the entire tuple id.
- * --------------
- */
- ItemPointerCopy(&tmpTag->tupleId, &tag->tupleId);
- break;
- }
-
- status = LockAcquire(lockmethod, tmpTag, locks[i]);
- if (!status)
- {
-
- /*
- * failed for some reason. Before returning we have to
- * release all of the locks we just acquired.
- * MultiRelease(xx,xx,xx, i) means release starting from
- * the last level lock we successfully acquired
- */
- retStatus = FALSE;
- MultiRelease(lockmethod, tag, lockmode, i);
- /* now leave the loop. Don't try for any more locks */
- break;
- }
- }
- }
- return retStatus;
-}
-
-/* ------------------
- * Release a page in the multi-level lock table
- * ------------------
- */
-#ifdef NOT_USED
-bool
-MultiReleasePage(LockInfo lockinfo, ItemPointer tidPtr, LOCKMODE lockmode)
-{
- LOCKTAG tag;
-
- /* ------------------
- * LOCKTAG has two bytes of padding, unfortunately. The
- * hash function will return miss if the padding bytes aren't
- * zero'd.
- * ------------------
- */
- MemSet(&tag, 0, sizeof(LOCKTAG));
-
- tag.relId = lockinfo->lockRelId.relId;
- tag.dbId = lockinfo->lockRelId.dbId;
- BlockIdCopy(&(tag.tupleId.ip_blkid), &(tidPtr->ip_blkid));
-
- return MultiRelease(MultiTableId, &tag, lockmode, PAGE_LEVEL);
-}
-
-#endif
-
-/* ------------------
- * Release a relation in the multi-level lock table
- * ------------------
- */
-bool
-MultiReleaseReln(LockInfo lockinfo, LOCKMODE lockmode)
-{
- LOCKTAG tag;
-
- /* ------------------
- * LOCKTAG has two bytes of padding, unfortunately. The
- * hash function will return miss if the padding bytes aren't
- * zero'd.
- * ------------------
- */
- MemSet(&tag, 0, sizeof(LOCKTAG));
- tag.relId = lockinfo->lockRelId.relId;
- tag.dbId = lockinfo->lockRelId.dbId;
-
- return MultiRelease(MultiTableId, &tag, lockmode, RELN_LEVEL);
-}
-
-/*
- * MultiRelease -- release a multi-level lock
- *
- * Returns: TRUE if successful, FALSE otherwise.
- */
-static bool
-MultiRelease(LOCKMETHOD lockmethod,
- LOCKTAG *tag,
- LOCKMODE lockmode,
- PG_LOCK_LEVEL level)
-{
- LOCKMODE locks[N_LEVELS];
- int i,
- status;
- LOCKTAG xxTag,
- *tmpTag = &xxTag;
-
- /*
- * same level scheme as MultiAcquire().
- */
- switch (level)
- {
- case RELN_LEVEL:
- locks[0] = lockmode;
- locks[1] = NO_LOCK;
- locks[2] = NO_LOCK;
- break;
- case PAGE_LEVEL:
- locks[0] = lockmode + INTENT;
- locks[1] = lockmode;
- locks[2] = NO_LOCK;
- break;
- case TUPLE_LEVEL:
- locks[0] = lockmode + INTENT;
- locks[1] = lockmode + INTENT;
- locks[2] = lockmode;
- break;
- default:
- elog(ERROR, "MultiRelease: bad lockmode");
- }
-
- /*
- * again, construct the tag on the fly. This time, however, we
- * release the locks in the REVERSE order -- from lowest level to
- * highest level.
- *
- * Must zero out the tag to set padding byes to zero and ensure hashing
- * consistency.
- */
- MemSet(tmpTag, 0, sizeof(*tmpTag));
- tmpTag->relId = tag->relId;
- tmpTag->dbId = tag->dbId;
-
- for (i = (N_LEVELS - 1); i >= 0; i--)
- {
- if (locks[i] != NO_LOCK)
- {
- switch (i)
- {
- case RELN_LEVEL:
- /* -------------
- * Set the block # and offset to invalid
- * -------------
- */
- BlockIdSet(&(tmpTag->tupleId.ip_blkid), InvalidBlockNumber);
- tmpTag->tupleId.ip_posid = InvalidOffsetNumber;
- break;
- case PAGE_LEVEL:
- /* -------------
- * Copy the block #, set the offset to invalid
- * -------------
- */
- BlockIdCopy(&(tmpTag->tupleId.ip_blkid),
- &(tag->tupleId.ip_blkid));
- tmpTag->tupleId.ip_posid = InvalidOffsetNumber;
- break;
- case TUPLE_LEVEL:
- ItemPointerCopy(&tmpTag->tupleId, &tag->tupleId);
- break;
- }
- status = LockRelease(lockmethod, tmpTag, locks[i]);
- if (!status)
- elog(ERROR, "MultiRelease: couldn't release after error");
- }
- }
- /* shouldn't reach here */
- return false;
-}
+++ /dev/null
-/*-------------------------------------------------------------------------
- *
- * single.c
- * set single locks in the multi-level lock hierarchy
- *
- * Sometimes we don't want to set all levels of the multi-level
- * lock hierarchy at once. This allows us to set and release
- * one level at a time. It's useful in index scans when
- * you can set an intent lock at the beginning and thereafter
- * only set page locks. Tends to speed things up.
- *
- * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *
- * IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/storage/lmgr/Attic/single.c,v 1.13 2000/01/26 05:57:02 momjian Exp $
- *
- *-------------------------------------------------------------------------
- */
-
-#include "postgres.h"
-
-#include "storage/lmgr.h"
-#include "storage/lock.h"
-#include "storage/multilev.h"
-#include "utils/rel.h"
-
-/*
- * SingleLockReln -- lock a relation
- *
- * Returns: TRUE if the lock can be set, FALSE otherwise.
- */
-bool
-SingleLockReln(LockInfo lockinfo, LOCKMODE lockmode, int action)
-{
- LOCKTAG tag;
-
- /*
- * LOCKTAG has two bytes of padding, unfortunately. The hash function
- * will return miss if the padding bytes aren't zero'd.
- */
- MemSet(&tag, 0, sizeof(tag));
- tag.relId = lockinfo->lockRelId.relId;
- tag.dbId = lockinfo->lockRelId.dbId;
- BlockIdSet(&(tag.tupleId.ip_blkid), InvalidBlockNumber);
- tag.tupleId.ip_posid = InvalidOffsetNumber;
-
- if (action == UNLOCK)
- return LockRelease(MultiTableId, &tag, lockmode);
- else
- return LockAcquire(MultiTableId, &tag, lockmode);
-}
-
-/*
- * SingleLockPage -- use multi-level lock table, but lock
- * only at the page level.
- *
- * Assumes that an INTENT lock has already been set in the
- * multi-level lock table.
- *
- */
-bool
-SingleLockPage(LockInfo lockinfo,
- ItemPointer tidPtr,
- LOCKMODE lockmode,
- int action)
-{
- LOCKTAG tag;
-
- /*
- * LOCKTAG has two bytes of padding, unfortunately. The hash function
- * will return miss if the padding bytes aren't zero'd.
- */
- MemSet(&tag, 0, sizeof(tag));
- tag.relId = lockinfo->lockRelId.relId;
- tag.dbId = lockinfo->lockRelId.dbId;
- BlockIdCopy(&(tag.tupleId.ip_blkid), &(tidPtr->ip_blkid));
- tag.tupleId.ip_posid = InvalidOffsetNumber;
-
-
- if (action == UNLOCK)
- return LockRelease(MultiTableId, &tag, lockmode);
- else
- return LockAcquire(MultiTableId, &tag, lockmode);
-}
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