*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/storage/lmgr/lock.c,v 1.129 2003/11/29 19:51:56 pgsql Exp $
+ * $PostgreSQL: pgsql/src/backend/storage/lmgr/lock.c,v 1.130 2003/12/01 21:59:25 momjian Exp $
*
* NOTES
* Outside modules can create a lock table and acquire/release
#define NLOCKENTS(maxBackends) (max_locks_per_xact * (maxBackends))
-static int WaitOnLock(LOCKMETHOD lockmethod, LOCKMODE lockmode,
+static int WaitOnLock(LOCKMETHODID lockmethodid, LOCKMODE lockmode,
LOCK *lock, PROCLOCK *proclock);
static void LockCountMyLocks(SHMEM_OFFSET lockOffset, PGPROC *proc,
int *myHolding);
"req(%d,%d,%d,%d,%d,%d,%d)=%d "
"grant(%d,%d,%d,%d,%d,%d,%d)=%d wait(%d) type(%s)",
where, MAKE_OFFSET(lock),
- lock->tag.lockmethod, lock->tag.relId, lock->tag.dbId,
+ lock->tag.lockmethodid, lock->tag.relId, lock->tag.dbId,
lock->tag.objId.blkno, lock->grantMask,
lock->requested[1], lock->requested[2], lock->requested[3],
lock->requested[4], lock->requested[5], lock->requested[6],
/*
- * These are to simplify/speed up some bit arithmetic.
- *
- * XXX is a fetch from a static array really faster than a shift?
- * Wouldn't bet on it...
+ * map from lock method id to the lock table structure
*/
-
-static LOCKMASK BITS_OFF[MAX_LOCKMODES];
-static LOCKMASK BITS_ON[MAX_LOCKMODES];
-
-/*
- * map from lockmethod to the lock table structure
- */
-static LOCKMETHODTABLE *LockMethodTable[MAX_LOCK_METHODS];
+static LockMethod LockMethods[MAX_LOCK_METHODS];
static int NumLockMethods;
void
InitLocks(void)
{
- int i;
- int bit;
-
- bit = 1;
- for (i = 0; i < MAX_LOCKMODES; i++, bit <<= 1)
- {
- BITS_ON[i] = bit;
- BITS_OFF[i] = ~bit;
- }
+ /* NOP */
}
/*
* Fetch the lock method table associated with a given lock
*/
-LOCKMETHODTABLE *
+LockMethod
GetLocksMethodTable(LOCK *lock)
{
- LOCKMETHOD lockmethod = LOCK_LOCKMETHOD(*lock);
+ LOCKMETHODID lockmethodid = LOCK_LOCKMETHOD(*lock);
- Assert(lockmethod > 0 && lockmethod < NumLockMethods);
- return LockMethodTable[lockmethod];
+ Assert(0 < lockmethodid && lockmethodid < NumLockMethods);
+ return LockMethods[lockmethodid];
}
* Notes: just copying. Should only be called once.
*/
static void
-LockMethodInit(LOCKMETHODTABLE *lockMethodTable,
+LockMethodInit(LockMethod lockMethodTable,
LOCKMASK *conflictsP,
int numModes)
{
* by the postmaster are inherited by each backend, so they must be in
* TopMemoryContext.
*/
-LOCKMETHOD
+LOCKMETHODID
LockMethodTableInit(char *tabName,
LOCKMASK *conflictsP,
int numModes,
int maxBackends)
{
- LOCKMETHODTABLE *lockMethodTable;
+ LockMethod newLockMethod;
char *shmemName;
HASHCTL info;
int hash_flags;
/* each lock table has a header in shared memory */
sprintf(shmemName, "%s (lock method table)", tabName);
- lockMethodTable = (LOCKMETHODTABLE *)
- ShmemInitStruct(shmemName, sizeof(LOCKMETHODTABLE), &found);
+ newLockMethod = (LockMethod)
+ ShmemInitStruct(shmemName, sizeof(LockMethodData), &found);
- if (!lockMethodTable)
+ if (!newLockMethod)
elog(FATAL, "could not initialize lock table \"%s\"", tabName);
/*
*/
if (!found)
{
- MemSet(lockMethodTable, 0, sizeof(LOCKMETHODTABLE));
- lockMethodTable->masterLock = LockMgrLock;
- lockMethodTable->lockmethod = NumLockMethods;
+ MemSet(newLockMethod, 0, sizeof(LockMethodData));
+ newLockMethod->masterLock = LockMgrLock;
+ newLockMethod->lockmethodid = NumLockMethods;
}
/*
* other modules refer to the lock table by a lockmethod ID
*/
- LockMethodTable[NumLockMethods] = lockMethodTable;
+ LockMethods[NumLockMethods] = newLockMethod;
NumLockMethods++;
Assert(NumLockMethods <= MAX_LOCK_METHODS);
hash_flags = (HASH_ELEM | HASH_FUNCTION);
sprintf(shmemName, "%s (lock hash)", tabName);
- lockMethodTable->lockHash = ShmemInitHash(shmemName,
- init_table_size,
- max_table_size,
- &info,
- hash_flags);
+ newLockMethod->lockHash = ShmemInitHash(shmemName,
+ init_table_size,
+ max_table_size,
+ &info,
+ hash_flags);
- if (!lockMethodTable->lockHash)
+ if (!newLockMethod->lockHash)
elog(FATAL, "could not initialize lock table \"%s\"", tabName);
- Assert(lockMethodTable->lockHash->hash == tag_hash);
+ Assert(newLockMethod->lockHash->hash == tag_hash);
/*
* allocate a hash table for PROCLOCK structs. This is used to store
hash_flags = (HASH_ELEM | HASH_FUNCTION);
sprintf(shmemName, "%s (proclock hash)", tabName);
- lockMethodTable->proclockHash = ShmemInitHash(shmemName,
- init_table_size,
- max_table_size,
- &info,
- hash_flags);
+ newLockMethod->proclockHash = ShmemInitHash(shmemName,
+ init_table_size,
+ max_table_size,
+ &info,
+ hash_flags);
- if (!lockMethodTable->proclockHash)
+ if (!newLockMethod->proclockHash)
elog(FATAL, "could not initialize lock table \"%s\"", tabName);
/* init data structures */
- LockMethodInit(lockMethodTable, conflictsP, numModes);
+ LockMethodInit(newLockMethod, conflictsP, numModes);
LWLockRelease(LockMgrLock);
pfree(shmemName);
- return lockMethodTable->lockmethod;
+ return newLockMethod->lockmethodid;
}
/*
* short term and long term locks, yet store them all in one hashtable.
*/
-LOCKMETHOD
-LockMethodTableRename(LOCKMETHOD lockmethod)
+LOCKMETHODID
+LockMethodTableRename(LOCKMETHODID lockmethodid)
{
- LOCKMETHOD newLockMethod;
+ LOCKMETHODID newLockMethodId;
if (NumLockMethods >= MAX_LOCK_METHODS)
return INVALID_LOCKMETHOD;
- if (LockMethodTable[lockmethod] == INVALID_LOCKMETHOD)
+ if (LockMethods[lockmethodid] == INVALID_LOCKMETHOD)
return INVALID_LOCKMETHOD;
/* other modules refer to the lock table by a lockmethod ID */
- newLockMethod = NumLockMethods;
+ newLockMethodId = NumLockMethods;
NumLockMethods++;
- LockMethodTable[newLockMethod] = LockMethodTable[lockmethod];
- return newLockMethod;
+ LockMethods[newLockMethodId] = LockMethods[lockmethodid];
+ return newLockMethodId;
}
/*
*
* normal lock user lock
*
- * lockmethod 1 2
+ * lockmethodid 1 2
* tag.dbId database oid database oid
* tag.relId rel oid or 0 0
* tag.objId block id lock id2
*/
bool
-LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
+LockAcquire(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
TransactionId xid, LOCKMODE lockmode, bool dontWait)
{
PROCLOCK *proclock;
bool found;
LOCK *lock;
LWLockId masterLock;
- LOCKMETHODTABLE *lockMethodTable;
+ LockMethod lockMethodTable;
int status;
int myHolding[MAX_LOCKMODES];
int i;
#ifdef LOCK_DEBUG
- if (lockmethod == USER_LOCKMETHOD && Trace_userlocks)
+ if (lockmethodid == USER_LOCKMETHOD && Trace_userlocks)
elog(LOG, "LockAcquire: user lock [%u] %s",
locktag->objId.blkno, lock_mode_names[lockmode]);
#endif
/* ???????? This must be changed when short term locks will be used */
- locktag->lockmethod = lockmethod;
+ locktag->lockmethodid = lockmethodid;
- Assert(lockmethod < NumLockMethods);
- lockMethodTable = LockMethodTable[lockmethod];
+ Assert(lockmethodid < NumLockMethods);
+ lockMethodTable = LockMethods[lockmethodid];
if (!lockMethodTable)
{
- elog(WARNING, "bad lock table id: %d", lockmethod);
+ elog(WARNING, "bad lock table id: %d", lockmethodid);
return FALSE;
}
* Construct bitmask of locks this process holds on this object.
*/
{
- int heldLocks = 0;
- int tmpMask;
+ LOCKMASK heldLocks = 0;
- for (i = 1, tmpMask = 2;
- i <= lockMethodTable->numLockModes;
- i++, tmpMask <<= 1)
+ for (i = 1; i <= lockMethodTable->numLockModes; i++)
{
if (myHolding[i] > 0)
- heldLocks |= tmpMask;
+ heldLocks |= LOCKBIT_ON(i);
}
MyProc->heldLocks = heldLocks;
}
/*
* Sleep till someone wakes me up.
*/
- status = WaitOnLock(lockmethod, lockmode, lock, proclock);
+ status = WaitOnLock(lockmethodid, lockmode, lock, proclock);
/*
* NOTE: do not do any material change of state between here and
* known. If NULL is passed then these values will be computed internally.
*/
int
-LockCheckConflicts(LOCKMETHODTABLE *lockMethodTable,
+LockCheckConflicts(LockMethod lockMethodTable,
LOCKMODE lockmode,
LOCK *lock,
PROCLOCK *proclock,
int *myHolding) /* myHolding[] array or NULL */
{
int numLockModes = lockMethodTable->numLockModes;
- int bitmask;
- int i,
- tmpMask;
+ LOCKMASK bitmask;
+ int i;
int localHolding[MAX_LOCKMODES];
/*
/* Compute mask of lock types held by other processes */
bitmask = 0;
- tmpMask = 2;
- for (i = 1; i <= numLockModes; i++, tmpMask <<= 1)
+ for (i = 1; i <= numLockModes; i++)
{
if (lock->granted[i] != myHolding[i])
- bitmask |= tmpMask;
+ bitmask |= LOCKBIT_ON(i);
}
/*
{
lock->nGranted++;
lock->granted[lockmode]++;
- lock->grantMask |= BITS_ON[lockmode];
+ lock->grantMask |= LOCKBIT_ON(lockmode);
if (lock->granted[lockmode] == lock->requested[lockmode])
- lock->waitMask &= BITS_OFF[lockmode];
+ lock->waitMask &= LOCKBIT_OFF(lockmode);
LOCK_PRINT("GrantLock", lock, lockmode);
Assert((lock->nGranted > 0) && (lock->granted[lockmode] > 0));
Assert(lock->nGranted <= lock->nRequested);
* The locktable's masterLock must be held at entry.
*/
static int
-WaitOnLock(LOCKMETHOD lockmethod, LOCKMODE lockmode,
+WaitOnLock(LOCKMETHODID lockmethodid, LOCKMODE lockmode,
LOCK *lock, PROCLOCK *proclock)
{
- LOCKMETHODTABLE *lockMethodTable = LockMethodTable[lockmethod];
+ LockMethod lockMethodTable = LockMethods[lockmethodid];
char *new_status,
*old_status;
- Assert(lockmethod < NumLockMethods);
+ Assert(lockmethodid < NumLockMethods);
LOCK_PRINT("WaitOnLock: sleeping on lock", lock, lockmode);
waitLock->requested[lockmode]--;
/* don't forget to clear waitMask bit if appropriate */
if (waitLock->granted[lockmode] == waitLock->requested[lockmode])
- waitLock->waitMask &= BITS_OFF[lockmode];
+ waitLock->waitMask &= LOCKBIT_OFF(lockmode);
/* Clean up the proc's own state */
proc->waitLock = NULL;
}
/*
- * LockRelease -- look up 'locktag' in lock table 'lockmethod' and
+ * LockRelease -- look up 'locktag' in lock table 'lockmethodid' and
* release one 'lockmode' lock on it.
*
* Side Effects: find any waiting processes that are now wakable,
* come along and request the lock.)
*/
bool
-LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag,
+LockRelease(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
TransactionId xid, LOCKMODE lockmode)
{
LOCK *lock;
LWLockId masterLock;
- LOCKMETHODTABLE *lockMethodTable;
+ LockMethod lockMethodTable;
PROCLOCK *proclock;
PROCLOCKTAG proclocktag;
HTAB *proclockTable;
bool wakeupNeeded = false;
#ifdef LOCK_DEBUG
- if (lockmethod == USER_LOCKMETHOD && Trace_userlocks)
+ if (lockmethodid == USER_LOCKMETHOD && Trace_userlocks)
elog(LOG, "LockRelease: user lock tag [%u] %d", locktag->objId.blkno, lockmode);
#endif
/* ???????? This must be changed when short term locks will be used */
- locktag->lockmethod = lockmethod;
+ locktag->lockmethodid = lockmethodid;
- Assert(lockmethod < NumLockMethods);
- lockMethodTable = LockMethodTable[lockmethod];
+ Assert(lockmethodid < NumLockMethods);
+ lockMethodTable = LockMethods[lockmethodid];
if (!lockMethodTable)
{
elog(WARNING, "lockMethodTable is null in LockRelease");
{
LWLockRelease(masterLock);
#ifdef USER_LOCKS
- if (lockmethod == USER_LOCKMETHOD)
+ if (lockmethodid == USER_LOCKMETHOD)
elog(WARNING, "no lock with this tag");
else
#endif
if (lock->granted[lockmode] == 0)
{
/* change the conflict mask. No more of this lock type. */
- lock->grantMask &= BITS_OFF[lockmode];
+ lock->grantMask &= LOCKBIT_OFF(lockmode);
}
LOCK_PRINT("LockRelease: updated", lock, lockmode);
* specified XID are released.
*/
bool
-LockReleaseAll(LOCKMETHOD lockmethod, PGPROC *proc,
+LockReleaseAll(LOCKMETHODID lockmethodid, PGPROC *proc,
bool allxids, TransactionId xid)
{
SHM_QUEUE *procHolders = &(proc->procHolders);
PROCLOCK *proclock;
PROCLOCK *nextHolder;
LWLockId masterLock;
- LOCKMETHODTABLE *lockMethodTable;
+ LockMethod lockMethodTable;
int i,
numLockModes;
LOCK *lock;
#ifdef LOCK_DEBUG
- if (lockmethod == USER_LOCKMETHOD ? Trace_userlocks : Trace_locks)
+ if (lockmethodid == USER_LOCKMETHOD ? Trace_userlocks : Trace_locks)
elog(LOG, "LockReleaseAll: lockmethod=%d, pid=%d",
- lockmethod, proc->pid);
+ lockmethodid, proc->pid);
#endif
- Assert(lockmethod < NumLockMethods);
- lockMethodTable = LockMethodTable[lockmethod];
+ Assert(lockmethodid < NumLockMethods);
+ lockMethodTable = LockMethods[lockmethodid];
if (!lockMethodTable)
{
- elog(WARNING, "bad lock method: %d", lockmethod);
+ elog(WARNING, "bad lock method: %d", lockmethodid);
return FALSE;
}
lock = (LOCK *) MAKE_PTR(proclock->tag.lock);
/* Ignore items that are not of the lockmethod to be removed */
- if (LOCK_LOCKMETHOD(*lock) != lockmethod)
+ if (LOCK_LOCKMETHOD(*lock) != lockmethodid)
goto next_item;
/* If not allxids, ignore items that are of the wrong xid */
lock->granted[i] -= proclock->holding[i];
Assert(lock->requested[i] >= 0 && lock->granted[i] >= 0);
if (lock->granted[i] == 0)
- lock->grantMask &= BITS_OFF[i];
+ lock->grantMask &= LOCKBIT_OFF(i);
/*
* Read comments in LockRelease
LWLockRelease(masterLock);
#ifdef LOCK_DEBUG
- if (lockmethod == USER_LOCKMETHOD ? Trace_userlocks : Trace_locks)
+ if (lockmethodid == USER_LOCKMETHOD ? Trace_userlocks : Trace_locks)
elog(LOG, "LockReleaseAll done");
#endif
size += MAXALIGN(sizeof(PROC_HDR)); /* ProcGlobal */
size += maxBackends * MAXALIGN(sizeof(PGPROC)); /* each MyProc */
- size += MAX_LOCK_METHODS * MAXALIGN(sizeof(LOCKMETHODTABLE)); /* each lockMethodTable */
+ size += MAX_LOCK_METHODS * MAXALIGN(sizeof(LockMethodData)); /* each lock method */
/* lockHash table */
size += hash_estimate_size(max_table_size, sizeof(LOCK));
LWLockAcquire(LockMgrLock, LW_EXCLUSIVE);
- proclockTable = LockMethodTable[DEFAULT_LOCKMETHOD]->proclockHash;
+ proclockTable = LockMethods[DEFAULT_LOCKMETHOD]->proclockHash;
data->nelements = i = proclockTable->hctl->nentries;
SHM_QUEUE *procHolders;
PROCLOCK *proclock;
LOCK *lock;
- int lockmethod = DEFAULT_LOCKMETHOD;
- LOCKMETHODTABLE *lockMethodTable;
+ int lockmethodid = DEFAULT_LOCKMETHOD;
+ LockMethod lockMethodTable;
proc = MyProc;
if (proc == NULL)
procHolders = &proc->procHolders;
- Assert(lockmethod < NumLockMethods);
- lockMethodTable = LockMethodTable[lockmethod];
+ Assert(lockmethodid < NumLockMethods);
+ lockMethodTable = LockMethods[lockmethodid];
if (!lockMethodTable)
return;
PGPROC *proc;
PROCLOCK *proclock;
LOCK *lock;
- int lockmethod = DEFAULT_LOCKMETHOD;
- LOCKMETHODTABLE *lockMethodTable;
+ int lockmethodid = DEFAULT_LOCKMETHOD;
+ LockMethod lockMethodTable;
HTAB *proclockTable;
HASH_SEQ_STATUS status;
if (proc == NULL)
return;
- Assert(lockmethod < NumLockMethods);
- lockMethodTable = LockMethodTable[lockmethod];
+ Assert(lockmethodid < NumLockMethods);
+ lockMethodTable = LockMethods[lockmethodid];
if (!lockMethodTable)
return;
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/storage/lock.h,v 1.74 2003/11/29 22:41:13 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/storage/lock.h,v 1.75 2003/12/01 21:59:25 momjian Exp $
*
*-------------------------------------------------------------------------
*/
typedef int LOCKMASK;
-
typedef int LOCKMODE;
-typedef int LOCKMETHOD;
-
/* MAX_LOCKMODES cannot be larger than the # of bits in LOCKMASK */
#define MAX_LOCKMODES 10
+#define LOCKBIT_ON(lockmode) (1 << (lockmode))
+#define LOCKBIT_OFF(lockmode) (~(1 << (lockmode)))
+
+typedef uint16 LOCKMETHODID;
/* MAX_LOCK_METHODS is the number of distinct lock control tables allowed */
#define MAX_LOCK_METHODS 3
-#define INVALID_TABLEID 0
-
-#define INVALID_LOCKMETHOD INVALID_TABLEID
+#define INVALID_LOCKMETHOD 0
#define DEFAULT_LOCKMETHOD 1
#define USER_LOCKMETHOD 2
+#define LockMethodIsValid(lockmethodid) ((lockmethodid) != INVALID_LOCKMETHOD)
+
/*
* There is normally only one lock method, the default one.
* If user locks are enabled, an additional lock method is present.
* masterLock -- synchronizes access to the table
*
*/
-typedef struct LOCKMETHODTABLE
+typedef struct LockMethodData
{
- HTAB *lockHash;
- HTAB *proclockHash;
- LOCKMETHOD lockmethod;
- int numLockModes;
- int conflictTab[MAX_LOCKMODES];
- LWLockId masterLock;
-} LOCKMETHODTABLE;
+ HTAB *lockHash;
+ HTAB *proclockHash;
+ LOCKMETHODID lockmethodid;
+ int numLockModes;
+ LOCKMASK conflictTab[MAX_LOCKMODES];
+ LWLockId masterLock;
+} LockMethodData;
+typedef LockMethodData *LockMethod;
/*
*/
OffsetNumber offnum;
- uint16 lockmethod; /* needed by userlocks */
+ LOCKMETHODID lockmethodid; /* needed by userlocks */
} LOCKTAG;
LOCKTAG tag; /* unique identifier of lockable object */
/* data */
- int grantMask; /* bitmask for lock types already granted */
- int waitMask; /* bitmask for lock types awaited */
+ LOCKMASK grantMask; /* bitmask for lock types already granted */
+ LOCKMASK waitMask; /* bitmask for lock types awaited */
SHM_QUEUE lockHolders; /* list of PROCLOCK objects assoc. with
* lock */
PROC_QUEUE waitProcs; /* list of PGPROC objects waiting on lock */
int nGranted; /* total of granted[] array */
} LOCK;
-#define LOCK_LOCKMETHOD(lock) ((lock).tag.lockmethod)
+#define LOCK_LOCKMETHOD(lock) ((lock).tag.lockmethodid)
/*
} PROCLOCK;
#define PROCLOCK_LOCKMETHOD(proclock) \
- (((LOCK *) MAKE_PTR((proclock).tag.lock))->tag.lockmethod)
+ (((LOCK *) MAKE_PTR((proclock).tag.lock))->tag.lockmethodid)
/*
* This struct holds information passed from lmgr internals to the lock
* function prototypes
*/
extern void InitLocks(void);
-extern LOCKMETHODTABLE *GetLocksMethodTable(LOCK *lock);
-extern LOCKMETHOD LockMethodTableInit(char *tabName, LOCKMASK *conflictsP,
+extern LockMethod GetLocksMethodTable(LOCK *lock);
+extern LOCKMETHODID LockMethodTableInit(char *tabName, LOCKMASK *conflictsP,
int numModes, int maxBackends);
-extern LOCKMETHOD LockMethodTableRename(LOCKMETHOD lockmethod);
-extern bool LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
+extern LOCKMETHODID LockMethodTableRename(LOCKMETHODID lockmethodid);
+extern bool LockAcquire(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
TransactionId xid, LOCKMODE lockmode, bool dontWait);
-extern bool LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag,
+extern bool LockRelease(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
TransactionId xid, LOCKMODE lockmode);
-extern bool LockReleaseAll(LOCKMETHOD lockmethod, PGPROC *proc,
+extern bool LockReleaseAll(LOCKMETHODID lockmethodid, PGPROC *proc,
bool allxids, TransactionId xid);
-extern int LockCheckConflicts(LOCKMETHODTABLE *lockMethodTable,
+extern int LockCheckConflicts(LockMethod lockMethodTable,
LOCKMODE lockmode,
LOCK *lock, PROCLOCK *proclock, PGPROC *proc,
int *myHolding);
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