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Postgres FD Implementation
Commit 7dbcf31b authored by Marc G. Fournier's avatar Marc G. Fournier
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From: Massimo Dal Zotto <dz@cs.unitn.it> 

lock.patch

        I have rewritten lock.c cleaning up the code and adding better
        assert checking I have also added some fields to the lock and
        xid tags for better support of user locks. There is also a new
        function which returns an array of pids owning a lock.
        I'm using this code from over six months and it works fine.
parent 1acf0d85
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src/backend/storage/lmgr/lock.c
View file @ 7dbcf31b
......@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lock.c,v 1.32 1998/06/30 02:33:31 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lock.c,v 1.33 1998/08/25 21:20:26 scrappy Exp $
*
* NOTES
* Outside modules can create a lock table and acquire/release
......@@ -18,11 +18,9 @@
*
* Interface:
*
* LockAcquire(), LockRelease(), LockMethodTableInit().
*
* LockReplace() is called only within this module and by the
* lkchain module. It releases a lock without looking
* the lock up in the lock table.
* LockAcquire(), LockRelease(), LockMethodTableInit(),
* LockMethodTableRename(), LockReleaseAll, LockOwners()
* LockResolveConflicts(), GrantLock()
*
* NOTE: This module is used to define new lock tables. The
* multi-level lock table (multi.c) used by the heap
......@@ -35,6 +33,7 @@
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h>
#include "postgres.h"
#include "miscadmin.h"
......@@ -49,25 +48,110 @@
#include "utils/palloc.h"
#include "access/xact.h"
#include "access/transam.h"
#include "utils/trace.h"
#include "utils/ps_status.h"
static int
WaitOnLock(LOCKMETHOD lockmethod, LOCK *lock, LOCKMODE lockmode);
/*#define LOCK_MGR_DEBUG*/
#ifndef LOCK_MGR_DEBUG
static int WaitOnLock(LOCKMETHOD lockmethod, LOCK *lock, LOCKMODE lockmode,
TransactionId xid);
#define LOCK_PRINT(where,tag,type)
#define LOCK_DUMP(where,lock,type)
#define LOCK_DUMP_AUX(where,lock,type)
/*
* lockDebugRelation can be used to trace unconditionally a single relation,
* for example pg_listener, if you suspect there are locking problems.
*
* lockDebugOidMin is is used to avoid tracing postgres relations, which
* would produce a lot of output. Unfortunately most system relations are
* created after bootstrap and have oid greater than BootstrapObjectIdData.
* If you are using tprintf you should specify a value greater than the max
* oid of system relations, which can be found with the following query:
*
* select max(int4in(int4out(oid))) from pg_class where relname ~ '^pg_';
*
* To get a useful lock trace you can use the following pg_options:
*
* -T "verbose,query,locks,userlocks,lock_debug_oidmin=17500"
*/
#define LOCKDEBUG(lockmethod) (pg_options[TRACE_SHORTLOCKS+lockmethod])
#define lockDebugRelation (pg_options[TRACE_LOCKRELATION])
#define lockDebugOidMin (pg_options[TRACE_LOCKOIDMIN])
#define lockReadPriority (pg_options[OPT_LOCKREADPRIORITY])
#ifdef LOCK_MGR_DEBUG
#define LOCK_PRINT(where,lock,type) \
if (((LOCKDEBUG(LOCK_LOCKMETHOD(*(lock))) >= 1) \
&& (lock->tag.relId >= lockDebugOidMin)) \
|| (lock->tag.relId == lockDebugRelation)) \
LOCK_PRINT_AUX(where,lock,type)
#define LOCK_PRINT_AUX(where,lock,type) \
TPRINTF(TRACE_ALL, \
"%s: lock(%x) tbl(%d) rel(%d) db(%d) tid(%d,%d) mask(%x) " \
"hold(%d,%d,%d,%d,%d)=%d " \
"act(%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.tupleId.ip_blkid.bi_hi<<16)+ \
lock->tag.tupleId.ip_blkid.bi_lo), \
lock->tag.tupleId.ip_posid, \
lock->mask, \
lock->holders[1], \
lock->holders[2], \
lock->holders[3], \
lock->holders[4], \
lock->holders[5], \
lock->nHolding, \
lock->activeHolders[1], \
lock->activeHolders[2], \
lock->activeHolders[3], \
lock->activeHolders[4], \
lock->activeHolders[5], \
lock->nActive, \
lock->waitProcs.size, \
lock_types[type])
#define XID_PRINT(where,xidentP) \
if (((LOCKDEBUG(XIDENT_LOCKMETHOD(*(xidentP))) >= 1) \
&& (((LOCK *)MAKE_PTR(xidentP->tag.lock))->tag.relId \
>= lockDebugOidMin)) \
|| (((LOCK *)MAKE_PTR(xidentP->tag.lock))->tag.relId \
== lockDebugRelation)) \
XID_PRINT_AUX(where,xidentP)
#define XID_PRINT_AUX(where,xidentP) \
TPRINTF(TRACE_ALL, \
"%s: xid(%x) lock(%x) tbl(%d) pid(%d) xid(%d) " \
"hold(%d,%d,%d,%d,%d)=%d", \
where, \
MAKE_OFFSET(xidentP), \
xidentP->tag.lock, \
XIDENT_LOCKMETHOD(*(xidentP)), \
xidentP->tag.pid, \
xidentP->tag.xid, \
xidentP->holders[1], \
xidentP->holders[2], \
xidentP->holders[3], \
xidentP->holders[4], \
xidentP->holders[5], \
xidentP->nHolding)
#define LOCK_TPRINTF(lock, args...) \
if (((LOCKDEBUG(LOCK_LOCKMETHOD(*(lock))) >= 1) \
&& (lock->tag.relId >= lockDebugOidMin)) \
|| (lock->tag.relId == lockDebugRelation)) \
TPRINTF(TRACE_ALL, args)
#else /* !LOCK_MGR_DEBUG */
#define LOCK_PRINT(where,lock,type)
#define LOCK_PRINT_AUX(where,lock,type)
#define XID_PRINT(where,xidentP)
#define XID_PRINT_AUX(where,xidentP)
#define LOCK_TPRINTF(lock, args...)
#endif /* !LOCK_MGR_DEBUG */
#else /* LOCK_MGR_DEBUG */
int lockDebug = 0;
unsigned int lock_debug_oid_min = BootstrapObjectIdData;
static char *lock_types[] = {
"NONE",
"",
"WRITE",
"READ",
"WRITE INTENT",
......@@ -75,59 +159,6 @@ static char *lock_types[] = {
"EXTEND"
};
#define LOCK_PRINT(where,tag,type)\
if ((lockDebug >= 1) && (tag->relId >= lock_debug_oid_min)) \
elog(DEBUG, \
"%s: pid (%d) rel (%d) dbid (%d) tid (%d,%d) type (%s)",where, \
MyProcPid,\
tag->relId, tag->dbId, \
((tag->tupleId.ip_blkid.bi_hi<<16)+\
tag->tupleId.ip_blkid.bi_lo),\
tag->tupleId.ip_posid, \
lock_types[type])
#define LOCK_DUMP(where,lock,type)\
if ((lockDebug >= 1) && (lock->tag.relId >= lock_debug_oid_min)) \
LOCK_DUMP_AUX(where,lock,type)
#define LOCK_DUMP_AUX(where,lock,type)\
elog(DEBUG, \
"%s: pid (%d) rel (%d) dbid (%d) tid (%d,%d) nHolding (%d) "\
"holders (%d,%d,%d,%d,%d) type (%s)",where, \
MyProcPid,\
lock->tag.relId, lock->tag.dbId, \
((lock->tag.tupleId.ip_blkid.bi_hi<<16)+\
lock->tag.tupleId.ip_blkid.bi_lo),\
lock->tag.tupleId.ip_posid, \
lock->nHolding,\
lock->holders[1],\
lock->holders[2],\
lock->holders[3],\
lock->holders[4],\
lock->holders[5],\
lock_types[type])
#define XID_PRINT(where,xidentP)\
if ((lockDebug >= 2) && \
(((LOCK *)MAKE_PTR(xidentP->tag.lock))->tag.relId \
>= lock_debug_oid_min)) \
elog(DEBUG,\
"%s: pid (%d) xid (%d) pid (%d) lock (%x) nHolding (%d) "\
"holders (%d,%d,%d,%d,%d)",\
where,\
MyProcPid,\
xidentP->tag.xid,\
xidentP->tag.pid,\
xidentP->tag.lock,\
xidentP->nHolding,\
xidentP->holders[1],\
xidentP->holders[2],\
xidentP->holders[3],\
xidentP->holders[4],\
xidentP->holders[5])
#endif /* LOCK_MGR_DEBUG */
SPINLOCK LockMgrLock; /* in Shmem or created in
* CreateSpinlocks() */
......@@ -171,6 +202,16 @@ InitLocks()
BITS_ON[i] = bit;
BITS_OFF[i] = ~bit;
}
#ifdef LOCK_MGR_DEBUG
/*
* If lockDebugOidMin value has not been specified
* in pg_options set a default value.
*/
if (!lockDebugOidMin) {
lockDebugOidMin = BootstrapObjectIdData;
}
#endif
}
/* -------------------
......@@ -234,7 +275,7 @@ LockMethodTableInit(char *tabName,
{
elog(NOTICE, "LockMethodTableInit: too many lock types %d greater than %d",
numModes, MAX_LOCKMODES);
return (INVALID_TABLEID);
return (INVALID_LOCKMETHOD);
}
/* allocate a string for the shmem index table lookup */
......@@ -242,7 +283,7 @@ LockMethodTableInit(char *tabName,
if (!shmemName)
{
elog(NOTICE, "LockMethodTableInit: couldn't malloc string %s \n", tabName);
return (INVALID_TABLEID);
return (INVALID_LOCKMETHOD);
}
/* each lock table has a non-shared header */
......@@ -251,7 +292,7 @@ LockMethodTableInit(char *tabName,
{
elog(NOTICE, "LockMethodTableInit: couldn't malloc lock table %s\n", tabName);
pfree(shmemName);
return (INVALID_TABLEID);
return (INVALID_LOCKMETHOD);
}
/* ------------------------
......@@ -354,7 +395,7 @@ LockMethodTableInit(char *tabName,
if (status)
return (lockMethodTable->ctl->lockmethod);
else
return (INVALID_TABLEID);
return (INVALID_LOCKMETHOD);
}
/*
......@@ -369,16 +410,16 @@ LockMethodTableInit(char *tabName,
* client to use different lockmethods when acquiring/releasing
* short term and long term locks.
*/
#ifdef NOT_USED
LOCKMETHOD
LockMethodTableRename(LOCKMETHOD lockmethod)
{
LOCKMETHOD newLockMethod;
if (NumLockMethods >= MAX_LOCK_METHODS)
return (INVALID_TABLEID);
if (LockMethodTable[lockmethod] == INVALID_TABLEID)
return (INVALID_TABLEID);
return (INVALID_LOCKMETHOD);
if (LockMethodTable[lockmethod] == INVALID_LOCKMETHOD)
return (INVALID_LOCKMETHOD);
/* other modules refer to the lock table by a lockmethod */
newLockMethod = NumLockMethods;
......@@ -387,7 +428,6 @@ LockMethodTableRename(LOCKMETHOD lockmethod)
LockMethodTable[newLockMethod] = LockMethodTable[lockmethod];
return (newLockMethod);
}
#endif
/*
* LockAcquire -- Check for lock conflicts, sleep if conflict found,
......@@ -398,8 +438,11 @@ LockMethodTableRename(LOCKMETHOD lockmethod)
* Side Effects: The lock is always acquired. No way to abort
* a lock acquisition other than aborting the transaction.
* Lock is recorded in the lkchain.
*
#ifdef USER_LOCKS
*
* Note on User Locks:
*
* User locks are handled totally on the application side as
* long term cooperative locks which extend beyond the normal
* transaction boundaries. Their purpose is to indicate to an
......@@ -421,24 +464,24 @@ LockMethodTableRename(LOCKMETHOD lockmethod)
* acquired if already held by another process. They must be
* released explicitly by the application but they are released
* automatically when a backend terminates.
* They are indicated by a dummy lockmethod 0 which doesn't have
* any table allocated but uses the normal lock table, and are
* distinguished from normal locks for the following differences:
* They are indicated by a lockmethod 2 which is an alias for the
* normal lock table, and are distinguished from normal locks
* for the following differences:
*
* normal lock user lock
*
* lockmethod 1 0
* lockmethod 1 2
* tag.relId rel oid 0
* tag.ItemPointerData.ip_blkid block id lock id2
* tag.ItemPointerData.ip_posid tuple offset lock id1
* xid.pid 0 backend pid
* xid.xid current xid 0
* xid.xid xid or 0 0
* persistence transaction user or backend
*
* The lockmode parameter can have the same values for normal locks
* although probably only WRITE_LOCK can have some practical use.
*
* DZ - 4 Oct 1996
* DZ - 22 Nov 1997
#endif
*/
......@@ -453,25 +496,27 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
SPINLOCK masterLock;
LOCKMETHODTABLE *lockMethodTable;
int status;
TransactionId myXid;
TransactionId xid;
#ifdef USER_LOCKS
int is_user_lock;
is_user_lock = (lockmethod == 0);
is_user_lock = (lockmethod == USER_LOCKMETHOD);
if (is_user_lock)
{
lockmethod = 1;
#ifdef USER_LOCKS_DEBUG
elog(NOTICE, "LockAcquire: user lock tag [%u,%u] %d",
locktag->tupleId.ip_posid,
((locktag->tupleId.ip_blkid.bi_hi << 16) +
locktag->tupleId.ip_blkid.bi_lo),
lockmode);
TPRINTF(TRACE_USERLOCKS, "LockAcquire: user lock [%u,%u] %s",
locktag->tupleId.ip_posid,
((locktag->tupleId.ip_blkid.bi_hi << 16) +
locktag->tupleId.ip_blkid.bi_lo),
lock_types[lockmode]);
#endif
}
#endif
/* ???????? This must be changed when short term locks will be used */
locktag->lockmethod = lockmethod;
Assert(lockmethod < NumLockMethods);
lockMethodTable = LockMethodTable[lockmethod];
if (!lockMethodTable)
......@@ -483,14 +528,16 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
if (LockingIsDisabled)
return (TRUE);
LOCK_PRINT("Acquire", locktag, lockmode);
masterLock = lockMethodTable->ctl->masterLock;
SpinAcquire(masterLock);
/*
* Find or create a lock with this tag
*/
Assert(lockMethodTable->lockHash->hash == tag_hash);
lock = (LOCK *) hash_search(lockMethodTable->lockHash, (Pointer) locktag, HASH_ENTER, &found);
lock = (LOCK *) hash_search(lockMethodTable->lockHash, (Pointer) locktag,
HASH_ENTER, &found);
if (!lock)
{
SpinRelease(masterLock);
......@@ -505,15 +552,19 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
if (!found)
{
lock->mask = 0;
ProcQueueInit(&(lock->waitProcs));
MemSet((char *) lock->holders, 0, sizeof(int) * MAX_LOCKMODES);
MemSet((char *) lock->activeHolders, 0, sizeof(int) * MAX_LOCKMODES);
lock->nHolding = 0;
lock->nActive = 0;
MemSet((char *) lock->holders, 0, sizeof(int) * MAX_LOCKMODES);
MemSet((char *) lock->activeHolders, 0, sizeof(int) * MAX_LOCKMODES);
ProcQueueInit(&(lock->waitProcs));
Assert(BlockIdEquals(&(lock->tag.tupleId.ip_blkid),
&(locktag->tupleId.ip_blkid)));
LOCK_PRINT("LockAcquire: new", lock, lockmode);
} else {
LOCK_PRINT("LockAcquire: found", lock, lockmode);
Assert((lock->nHolding > 0) && (lock->holders[lockmode] >= 0));
Assert((lock->nActive > 0) && (lock->activeHolders[lockmode] >= 0));
Assert(lock->nActive <= lock->nHolding);
}
/* ------------------
......@@ -522,7 +573,6 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
* ------------------
*/
xidTable = lockMethodTable->xidHash;
myXid = GetCurrentTransactionId();
/* ------------------
* Zero out all of the tag bytes (this clears the padding bytes for long
......@@ -530,36 +580,48 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
* ------------------
*/
MemSet(&item, 0, XID_TAGSIZE); /* must clear padding, needed */
TransactionIdStore(myXid, &item.tag.xid);
item.tag.lock = MAKE_OFFSET(lock);
#if 0
item.tag.pid = MyPid;
#ifdef USE_XIDTAG_LOCKMETHOD
item.tag.lockmethod = lockmethod;
#endif
#ifdef USER_LOCKS
if (is_user_lock)
{
item.tag.pid = MyProcPid;
item.tag.xid = myXid = 0;
#ifdef USER_LOCKS_DEBUG
elog(NOTICE, "LockAcquire: user lock xid [%d,%d,%d]",
item.tag.lock, item.tag.pid, item.tag.xid);
#endif
item.tag.xid = xid = 0;
} else {
xid = GetCurrentTransactionId();
TransactionIdStore(xid, &item.tag.xid);
}
#else
xid = GetCurrentTransactionId();
TransactionIdStore(xid, &item.tag.xid);
#endif
result = (XIDLookupEnt *) hash_search(xidTable, (Pointer) &item, HASH_ENTER, &found);
/*
* Find or create an xid entry with this tag
*/
result = (XIDLookupEnt *) hash_search(xidTable, (Pointer) &item,
HASH_ENTER, &found);
if (!result)
{
elog(NOTICE, "LockAcquire: xid table corrupted");
return (STATUS_ERROR);
}
/*
* If not found initialize the new entry
*/
if (!found)
{
XID_PRINT("LockAcquire: queueing XidEnt", result);
ProcAddLock(&result->queue);
result->nHolding = 0;
MemSet((char *) result->holders, 0, sizeof(int) * MAX_LOCKMODES);
ProcAddLock(&result->queue);
XID_PRINT("LockAcquire: new", result);
} else {
XID_PRINT("LockAcquire: found", result);
Assert((result->nHolding > 0) && (result->holders[lockmode] >= 0));
Assert(result->nHolding <= lock->nActive);
}
/* ----------------
......@@ -570,6 +632,7 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
*/
lock->nHolding++;
lock->holders[lockmode]++;
Assert((lock->nHolding > 0) && (lock->holders[lockmode] > 0));
/* --------------------
* If I'm the only one holding a lock, then there
......@@ -582,43 +645,59 @@ LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
{
result->holders[lockmode]++;
result->nHolding++;
XID_PRINT("LockAcquire: owning", result);
Assert((result->nHolding > 0) && (result->holders[lockmode] > 0));
GrantLock(lock, lockmode);
SpinRelease(masterLock);
return (TRUE);
}
Assert(result->nHolding <= lock->nActive);
status = LockResolveConflicts(lockmethod, lock, lockmode, myXid);
status = LockResolveConflicts(lockmethod, lock, lockmode, xid, result);
if (status == STATUS_OK)
GrantLock(lock, lockmode);
else if (status == STATUS_FOUND)
{
#ifdef USER_LOCKS
/*
* User locks are non blocking. If we can't acquire a lock remove
* the xid entry and return FALSE without waiting.
* User locks are non blocking. If we can't acquire a lock we must
* remove the xid entry and return FALSE without waiting.
*/
if (is_user_lock)
{
if (!result->nHolding)
{
SHMQueueDelete(&result->queue);
hash_search(xidTable, (Pointer) &item, HASH_REMOVE, &found);
result = (XIDLookupEnt *) hash_search(xidTable,
(Pointer) &result,
HASH_REMOVE, &found);
if (!result || !found) {
elog(NOTICE, "LockAcquire: remove xid, table corrupted");
}
} else {
XID_PRINT_AUX("LockAcquire: NHOLDING", result);
}
lock->nHolding--;
lock->holders[lockmode]--;
LOCK_PRINT("LockAcquire: user lock failed", lock, lockmode);
Assert((lock->nHolding > 0) && (lock->holders[lockmode] >= 0));
Assert(lock->nActive <= lock->nHolding);
SpinRelease(masterLock);
#ifdef USER_LOCKS_DEBUG
elog(NOTICE, "LockAcquire: user lock failed");
#endif
return (FALSE);
}
#endif
status = WaitOnLock(lockmethod, lock, lockmode);
XID_PRINT("Someone granted me the lock", result);
status = WaitOnLock(lockmethod, lock, lockmode, xid);
/*
* Check the xid entry status, in case something in the
* ipc communication doesn't work correctly.
*/
if (!((result->nHolding > 0) && (result->holders[lockmode] > 0))) {
XID_PRINT_AUX("LockAcquire: INCONSISTENT ", result);
LOCK_PRINT_AUX("LockAcquire: INCONSISTENT ", lock, lockmode);
/* Should we retry ? */
return (FALSE);
}
XID_PRINT("LockAcquire: granted", result);
LOCK_PRINT("LockAcquire: granted", lock, lockmode);
}
SpinRelease(masterLock);
......@@ -646,7 +725,8 @@ int
LockResolveConflicts(LOCKMETHOD lockmethod,
LOCK *lock,
LOCKMODE lockmode,
TransactionId xid)
TransactionId xid,
XIDLookupEnt *xidentP) /* xident ptr or NULL */
{
XIDLookupEnt *result,
item;
......@@ -657,44 +737,81 @@ LockResolveConflicts(LOCKMETHOD lockmethod,
int bitmask;
int i,
tmpMask;
#ifdef USER_LOCKS
int is_user_lock;
#endif
numLockModes = LockMethodTable[lockmethod]->ctl->numLockModes;
xidTable = LockMethodTable[lockmethod]->xidHash;
/* ---------------------
* read my own statistics from the xid table. If there
* isn't an entry, then we'll just add one.
*
* Zero out the tag, this clears the padding bytes for long
* word alignment and ensures hashing consistency.
* ------------------
*/
MemSet(&item, 0, XID_TAGSIZE);
TransactionIdStore(xid, &item.tag.xid);
item.tag.lock = MAKE_OFFSET(lock);
#if 0
item.tag.pid = pid;
if (xidentP) {
/*
* A pointer to the xid entry was supplied from the caller.
* Actually only LockAcquire can do it.
*/
result = xidentP;
} else {
/* ---------------------
* read my own statistics from the xid table. If there
* isn't an entry, then we'll just add one.
*
* Zero out the tag, this clears the padding bytes for long
* word alignment and ensures hashing consistency.
* ------------------
*/
MemSet(&item, 0, XID_TAGSIZE);
item.tag.lock = MAKE_OFFSET(lock);
#ifdef USE_XIDTAG_LOCKMETHOD
item.tag.lockmethod = lockmethod;
#endif
#ifdef USER_LOCKS
is_user_lock = (lockmethod == 2);
if (is_user_lock) {
item.tag.pid = MyProcPid;
item.tag.xid = 0;
} else {
TransactionIdStore(xid, &item.tag.xid);
}
#else
TransactionIdStore(xid, &item.tag.xid);
#endif
if (!(result = (XIDLookupEnt *)
hash_search(xidTable, (Pointer) &item, HASH_ENTER, &found)))
{
elog(NOTICE, "LockResolveConflicts: xid table corrupted");
return (STATUS_ERROR);
}
myHolders = result->holders;
/*
* Find or create an xid entry with this tag
*/
result = (XIDLookupEnt *) hash_search(xidTable, (Pointer) &item,
HASH_ENTER, &found);
if (!result)
{
elog(NOTICE, "LockResolveConflicts: xid table corrupted");
return (STATUS_ERROR);
}
if (!found)
{
/* ---------------
* we're not holding any type of lock yet. Clear
* the lock stats.
* ---------------
/*
* If not found initialize the new entry. THIS SHOULD NEVER HAPPEN,
* if we are trying to resolve a conflict we must already have
* allocated an xid entry for this lock. dz 21-11-1997
*/
MemSet(result->holders, 0, numLockModes * sizeof(*(lock->holders)));
result->nHolding = 0;
if (!found)
{
/* ---------------
* we're not holding any type of lock yet. Clear
* the lock stats.
* ---------------
*/
MemSet(result->holders,0, numLockModes * sizeof(*(lock->holders)));
result->nHolding = 0;
XID_PRINT_AUX("LockResolveConflicts: NOT FOUND", result);
} else {
XID_PRINT("LockResolveConflicts: found", result);
}
}
Assert((result->nHolding >= 0) && (result->holders[lockmode] >= 0));
/*
* We can control runtime this option. Default is lockReadPriority=0
*/
if (!lockReadPriority)
{
/* ------------------------
* If someone with a greater priority is waiting for the lock,
......@@ -705,8 +822,11 @@ LockResolveConflicts(LOCKMETHOD lockmethod,
PROC_QUEUE *waitQueue = &(lock->waitProcs);
PROC *topproc = (PROC *) MAKE_PTR(waitQueue->links.prev);
if (waitQueue->size && topproc->prio > myprio)
if (waitQueue->size && topproc->prio > myprio) {
XID_PRINT("LockResolveConflicts: higher priority proc waiting",
result);
return STATUS_FOUND;
}
}
/* ----------------------------
......@@ -721,12 +841,10 @@ LockResolveConflicts(LOCKMETHOD lockmethod,
*/
if (!(LockMethodTable[lockmethod]->ctl->conflictTab[lockmode] & lock->mask))
{
result->holders[lockmode]++;
result->nHolding++;
XID_PRINT("Conflict Resolved: updated xid entry stats", result);
XID_PRINT("LockResolveConflicts: no conflict", result);
Assert((result->nHolding > 0) && (result->holders[lockmode] > 0));
return (STATUS_OK);
}
......@@ -736,6 +854,7 @@ LockResolveConflicts(LOCKMETHOD lockmethod,
* that does not reflect our own locks.
* ------------------------
*/
myHolders = result->holders;
bitmask = 0;
tmpMask = 2;
for (i = 1; i <= numLockModes; i++, tmpMask <<= 1)
......@@ -753,27 +872,42 @@ LockResolveConflicts(LOCKMETHOD lockmethod,
*/
if (!(LockMethodTable[lockmethod]->ctl->conflictTab[lockmode] & bitmask))
{
/* no conflict. Get the lock and go on */
result->holders[lockmode]++;
result->nHolding++;
XID_PRINT("Conflict Resolved: updated xid entry stats", result);
XID_PRINT("LockResolveConflicts: resolved", result);
Assert((result->nHolding > 0) && (result->holders[lockmode] > 0));
return (STATUS_OK);
}
XID_PRINT("LockResolveConflicts: conflicting", result);
return (STATUS_FOUND);
}
/*
* GrantLock -- update the lock data structure to show
* the new lock holder.
*/
void
GrantLock(LOCK *lock, LOCKMODE lockmode)
{
lock->nActive++;
lock->activeHolders[lockmode]++;
lock->mask |= BITS_ON[lockmode];
LOCK_PRINT("GrantLock", lock, lockmode);
Assert((lock->nActive > 0) && (lock->activeHolders[lockmode] > 0));
Assert(lock->nActive <= lock->nHolding);
}
static int
WaitOnLock(LOCKMETHOD lockmethod, LOCK *lock, LOCKMODE lockmode)
WaitOnLock(LOCKMETHOD lockmethod, LOCK *lock, LOCKMODE lockmode,
TransactionId xid)
{
PROC_QUEUE *waitQueue = &(lock->waitProcs);
LOCKMETHODTABLE *lockMethodTable = LockMethodTable[lockmethod];
int prio = lockMethodTable->ctl->prio[lockmode];
char old_status[64],
new_status[64];
Assert(lockmethod < NumLockMethods);
......@@ -785,27 +919,38 @@ WaitOnLock(LOCKMETHOD lockmethod, LOCK *lock, LOCKMODE lockmode)
* synchronization for this queue. That will not be true if/when
* people can be deleted from the queue by a SIGINT or something.
*/
LOCK_DUMP_AUX("WaitOnLock: sleeping on lock", lock, lockmode);
LOCK_PRINT_AUX("WaitOnLock: sleeping on lock", lock, lockmode);
strcpy(old_status, PS_STATUS);
strcpy(new_status, PS_STATUS);
strcat(new_status, " waiting");
PS_SET_STATUS(new_status);
if (ProcSleep(waitQueue,
lockMethodTable->ctl->masterLock,
lockmode,
prio,
lock) != NO_ERROR)
lock,
xid) != NO_ERROR)
{
/* -------------------
* This could have happend as a result of a deadlock, see HandleDeadLock()
* Decrement the lock nHolding and holders fields as we are no longer
* waiting on this lock.
* This could have happend as a result of a deadlock,
* see HandleDeadLock().
* Decrement the lock nHolding and holders fields as
* we are no longer waiting on this lock.
* -------------------
*/
lock->nHolding--;
lock->holders[lockmode]--;
LOCK_DUMP_AUX("WaitOnLock: aborting on lock", lock, lockmode);
LOCK_PRINT_AUX("WaitOnLock: aborting on lock", lock, lockmode);
Assert((lock->nHolding >= 0) && (lock->holders[lockmode] >= 0));
Assert(lock->nActive <= lock->nHolding);
SpinRelease(lockMethodTable->ctl->masterLock);
elog(ERROR, "WaitOnLock: error on wakeup - Aborting this transaction");
/* not reached */
}
LOCK_DUMP_AUX("WaitOnLock: wakeup on lock", lock, lockmode);
PS_SET_STATUS(old_status);
LOCK_PRINT_AUX("WaitOnLock: wakeup on lock", lock, lockmode);
return (STATUS_OK);
}
......@@ -829,25 +974,34 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
XIDLookupEnt *result,
item;
HTAB *xidTable;
TransactionId xid;
bool wakeupNeeded = true;
int trace_flag;
#ifdef USER_LOCKS
int is_user_lock;
is_user_lock = (lockmethod == 0);
is_user_lock = (lockmethod == USER_LOCKMETHOD);
if (is_user_lock)
{
lockmethod = 1;
#ifdef USER_LOCKS_DEBUG
elog(NOTICE, "LockRelease: user lock tag [%u,%u] %d",
locktag->tupleId.ip_posid,
((locktag->tupleId.ip_blkid.bi_hi << 16) +
locktag->tupleId.ip_blkid.bi_lo),
lockmode);
#endif
TPRINTF(TRACE_USERLOCKS, "LockRelease: user lock tag [%u,%u] %d",
locktag->tupleId.ip_posid,
((locktag->tupleId.ip_blkid.bi_hi << 16) +
locktag->tupleId.ip_blkid.bi_lo),
lockmode);
}
#endif
/* ???????? This must be changed when short term locks will be used */
locktag->lockmethod = lockmethod;
#ifdef USER_LOCKS
trace_flag = \
(lockmethod == USER_LOCKMETHOD) ? TRACE_USERLOCKS : TRACE_LOCKS;
#else
trace_flag = TRACE_LOCKS;
#endif
Assert(lockmethod < NumLockMethods);
lockMethodTable = LockMethodTable[lockmethod];
if (!lockMethodTable)
......@@ -859,34 +1013,18 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
if (LockingIsDisabled)
return (TRUE);
LOCK_PRINT("Release", locktag, lockmode);
masterLock = lockMethodTable->ctl->masterLock;
xidTable = lockMethodTable->xidHash;
SpinAcquire(masterLock);
Assert(lockMethodTable->lockHash->hash == tag_hash);
lock = (LOCK *)
hash_search(lockMethodTable->lockHash, (Pointer) locktag, HASH_FIND_SAVE, &found);
#ifdef USER_LOCKS
/*
* If the entry is not found hash_search returns TRUE instead of NULL,
* so we must check it explicitly.
* Find a lock with this tag
*/
if ((is_user_lock) && (lock == (LOCK *) TRUE))
{
SpinRelease(masterLock);
elog(NOTICE, "LockRelease: there are no locks with this tag");
return (FALSE);
}
#endif
Assert(lockMethodTable->lockHash->hash == tag_hash);
lock = (LOCK *) hash_search(lockMethodTable->lockHash, (Pointer) locktag,
HASH_FIND, &found);
/*
* let the caller print its own error message, too. Do not
* elog(ERROR).
* let the caller print its own error message, too. Do not elog(ERROR).
*/
if (!lock)
{
......@@ -898,52 +1036,20 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
if (!found)
{
SpinRelease(masterLock);
#ifdef USER_LOCKS
if (is_user_lock) {
TPRINTF(TRACE_USERLOCKS, "LockRelease: no lock with this tag");
return (FALSE);
}
#endif
elog(NOTICE, "LockRelease: locktable lookup failed, no lock");
return (FALSE);
}
LOCK_PRINT("LockRelease: found", lock, lockmode);
Assert((lock->nHolding > 0) && (lock->holders[lockmode] >= 0));
Assert((lock->nActive > 0) && (lock->activeHolders[lockmode] >= 0));
Assert(lock->nActive <= lock->nHolding);
Assert(lock->nHolding > 0);
#ifdef USER_LOCKS
/*
* If this is an user lock it can be removed only after checking that
* it was acquired by the current process, so this code is skipped and
* executed later.
*/
if (!is_user_lock)
{
#endif
/*
* fix the general lock stats
*/
lock->nHolding--;
lock->holders[lockmode]--;
lock->nActive--;
lock->activeHolders[lockmode]--;
Assert(lock->nActive >= 0);
if (!lock->nHolding)
{
/* ------------------
* if there's no one waiting in the queue,
* we just released the last lock.
* Delete it from the lock table.
* ------------------
*/
Assert(lockMethodTable->lockHash->hash == tag_hash);
lock = (LOCK *) hash_search(lockMethodTable->lockHash,
(Pointer) &(lock->tag),
HASH_REMOVE_SAVED,
&found);
Assert(lock && found);
wakeupNeeded = false;
}
#ifdef USER_LOCKS
}
#endif
/* ------------------
* Zero out all of the tag bytes (this clears the padding bytes for long
......@@ -951,42 +1057,102 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
* ------------------
*/
MemSet(&item, 0, XID_TAGSIZE);
TransactionIdStore(GetCurrentTransactionId(), &item.tag.xid);
item.tag.lock = MAKE_OFFSET(lock);
#if 0
item.tag.pid = MyPid;
#ifdef USE_XIDTAG_LOCKMETHOD
item.tag.lockmethod = lockmethod;
#endif
#ifdef USER_LOCKS
if (is_user_lock)
{
if (is_user_lock) {
item.tag.pid = MyProcPid;
item.tag.xid = 0;
#ifdef USER_LOCKS_DEBUG
elog(NOTICE, "LockRelease: user lock xid [%d,%d,%d]",
item.tag.lock, item.tag.pid, item.tag.xid);
#endif
item.tag.xid = xid = 0;
} else {
xid = GetCurrentTransactionId();
TransactionIdStore(xid, &item.tag.xid);
}
#else
xid = GetCurrentTransactionId();
TransactionIdStore(xid, &item.tag.xid);
#endif
if (!(result = (XIDLookupEnt *) hash_search(xidTable,
(Pointer) &item,
HASH_FIND_SAVE,
&found))
|| !found)
/*
* Find an xid entry with this tag
*/
xidTable = lockMethodTable->xidHash;
result = (XIDLookupEnt *) hash_search(xidTable, (Pointer) &item,
HASH_FIND_SAVE, &found);
if (!result || !found)
{
SpinRelease(masterLock);
#ifdef USER_LOCKS
if ((is_user_lock) && (result))
elog(NOTICE, "LockRelease: you don't have a lock on this tag");
else
elog(NOTICE, "LockRelease: find xid, table corrupted");
#else
elog(NOTICE, "LockReplace: xid table corrupted");
if (!found && is_user_lock) {
TPRINTF(TRACE_USERLOCKS, "LockRelease: no lock with this tag");
} else
#endif
elog(NOTICE, "LockReplace: xid table corrupted");
return (FALSE);
}
XID_PRINT("LockRelease: found", result);
Assert(result->tag.lock == MAKE_OFFSET(lock));
/*
* Check that we are actually holding a lock of the type we want
* to release.
*/
if (!(result->holders[lockmode] > 0)) {
SpinRelease(masterLock);
XID_PRINT_AUX("LockAcquire: WRONGTYPE", result);
elog(NOTICE, "LockRelease: you don't own a lock of type %s",
lock_types[lockmode]);
Assert(result->holders[lockmode] >= 0);
return (FALSE);
}
Assert(result->nHolding > 0);
/*
* fix the general lock stats
*/
lock->nHolding--;
lock->holders[lockmode]--;
lock->nActive--;
lock->activeHolders[lockmode]--;
/* --------------------------
* If there are still active locks of the type I just released, no one
* should be woken up. Whoever is asleep will still conflict
* with the remaining locks.
* --------------------------
*/
if (lock->activeHolders[lockmode])
{
wakeupNeeded = false;
}
else
{
/* change the conflict mask. No more of this lock type. */
lock->mask &= BITS_OFF[lockmode];
}
LOCK_PRINT("LockRelease: updated", lock, lockmode);
Assert((lock->nHolding >= 0) && (lock->holders[lockmode] >= 0));
Assert((lock->nActive >= 0) && (lock->activeHolders[lockmode] >= 0));
Assert(lock->nActive <= lock->nHolding);
if (!lock->nHolding)
{
/* ------------------
* if there's no one waiting in the queue,
* we just released the last lock.
* Delete it from the lock table.
* ------------------
*/
Assert(lockMethodTable->lockHash->hash == tag_hash);
lock = (LOCK *) hash_search(lockMethodTable->lockHash,
(Pointer) &(lock->tag),
HASH_REMOVE,
&found);
Assert(lock && found);
wakeupNeeded = false;
}
/*
* now check to see if I have any private locks. If I do, decrement
......@@ -994,8 +1160,8 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
*/
result->holders[lockmode]--;
result->nHolding--;
XID_PRINT("LockRelease updated xid stats", result);
XID_PRINT("LockRelease: updated", result);
Assert((result->nHolding >= 0) && (result->holders[lockmode] >= 0));
/*
* If this was my last hold on this lock, delete my entry in the XID
......@@ -1003,78 +1169,25 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
*/
if (!result->nHolding)
{
#ifdef USER_LOCKS
if (result->queue.prev == INVALID_OFFSET)
if (result->queue.prev == INVALID_OFFSET) {
elog(NOTICE, "LockRelease: xid.prev == INVALID_OFFSET");
if (result->queue.next == INVALID_OFFSET)
}
if (result->queue.next == INVALID_OFFSET) {
elog(NOTICE, "LockRelease: xid.next == INVALID_OFFSET");
#endif
}
if (result->queue.next != INVALID_OFFSET)
SHMQueueDelete(&result->queue);
if (!(result = (XIDLookupEnt *)
hash_search(xidTable, (Pointer) &item, HASH_REMOVE_SAVED, &found)) ||
!found)
XID_PRINT("LockRelease: deleting", result);
result = (XIDLookupEnt *) hash_search(xidTable, (Pointer) &result,
HASH_REMOVE_SAVED, &found);
if (!result || !found)
{
SpinRelease(masterLock);
#ifdef USER_LOCKS
elog(NOTICE, "LockRelease: remove xid, table corrupted");
#else
elog(NOTICE, "LockReplace: xid table corrupted");
#endif
return (FALSE);
}
}
#ifdef USER_LOCKS
/*
* If this is an user lock remove it now, after the corresponding xid
* entry has been found and deleted.
*/
if (is_user_lock)
{
/*
* fix the general lock stats
*/
lock->nHolding--;
lock->holders[lockmode]--;
lock->nActive--;
lock->activeHolders[lockmode]--;
Assert(lock->nActive >= 0);
if (!lock->nHolding)
{
/* ------------------
* if there's no one waiting in the queue,
* we just released the last lock.
* Delete it from the lock table.
* ------------------
*/
Assert(lockMethodTable->lockHash->hash == tag_hash);
lock = (LOCK *) hash_search(lockMethodTable->lockHash,
(Pointer) &(lock->tag),
HASH_REMOVE,
&found);
Assert(lock && found);
wakeupNeeded = false;
}
}
#endif
/* --------------------------
* If there are still active locks of the type I just released, no one
* should be woken up. Whoever is asleep will still conflict
* with the remaining locks.
* --------------------------
*/
if (!(lock->activeHolders[lockmode]))
{
/* change the conflict mask. No more of this lock type. */
lock->mask &= BITS_OFF[lockmode];
}
if (wakeupNeeded)
{
/* --------------------------
......@@ -1085,35 +1198,18 @@ LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode)
*/
ProcLockWakeup(&(lock->waitProcs), lockmethod, lock);
}
else
{
LOCK_TPRINTF(lock, "LockRelease: no wakeup needed");
}
SpinRelease(masterLock);
return (TRUE);
}
/*
* GrantLock -- update the lock data structure to show
* the new lock holder.
*/
void
GrantLock(LOCK *lock, LOCKMODE lockmode)
{
lock->nActive++;
lock->activeHolders[lockmode]++;
lock->mask |= BITS_ON[lockmode];
}
#ifdef USER_LOCKS
/*
* LockReleaseAll -- Release all locks in a process lock queue.
*
* Note: This code is a little complicated by the presence in the
* same queue of user locks which can't be removed from the
* normal lock queue at the end of a transaction. They must
* however be removed when the backend exits.
* A dummy lockmethod 0 is used to indicate that we are releasing
* the user locks, from the code added to ProcKill().
*/
#endif
bool
LockReleaseAll(LOCKMETHOD lockmethod, SHM_QUEUE *lockQueue)
{
......@@ -1121,6 +1217,7 @@ LockReleaseAll(LOCKMETHOD lockmethod, SHM_QUEUE *lockQueue)
int done;
XIDLookupEnt *xidLook = NULL;
XIDLookupEnt *tmp = NULL;
XIDLookupEnt *result;
SHMEM_OFFSET end = MAKE_OFFSET(lockQueue);
SPINLOCK masterLock;
LOCKMETHODTABLE *lockMethodTable;
......@@ -1128,45 +1225,52 @@ LockReleaseAll(LOCKMETHOD lockmethod, SHM_QUEUE *lockQueue)
numLockModes;
LOCK *lock;
bool found;
int trace_flag;
int xidtag_lockmethod;
#ifdef USER_LOCKS
int is_user_lock_table,
count,
nskip;
nleft;
is_user_lock_table = (lockmethod == 0);
#ifdef USER_LOCKS_DEBUG
elog(NOTICE, "LockReleaseAll: lockmethod=%d, pid=%d", lockmethod, MyProcPid);
#endif
if (is_user_lock_table)
lockmethod = 1;
count = nleft = 0;
is_user_lock_table = (lockmethod == USER_LOCKMETHOD);
trace_flag = (lockmethod == 2) ? TRACE_USERLOCKS : TRACE_LOCKS;
#else
trace_flag = TRACE_LOCKS;
#endif
TPRINTF(trace_flag, "LockReleaseAll: lockmethod=%d, pid=%d",
lockmethod, MyProcPid);
Assert(lockmethod < NumLockMethods);
lockMethodTable = LockMethodTable[lockmethod];
if (!lockMethodTable)
if (!lockMethodTable) {
elog(NOTICE, "LockAcquire: bad lockmethod %d", lockmethod);
return (FALSE);
numLockModes = lockMethodTable->ctl->numLockModes;
masterLock = lockMethodTable->ctl->masterLock;
}
if (SHMQueueEmpty(lockQueue))
return TRUE;
#ifdef USER_LOCKS
numLockModes = lockMethodTable->ctl->numLockModes;
masterLock = lockMethodTable->ctl->masterLock;
SpinAcquire(masterLock);
#endif
SHMQueueFirst(lockQueue, (Pointer *) &xidLook, &xidLook->queue);
XID_PRINT("LockReleaseAll", xidLook);
#ifndef USER_LOCKS
SpinAcquire(masterLock);
#else
count = nskip = 0;
#endif
for (;;)
{
/*
* Sometimes the queue appears to be messed up.
*/
if (count++ > 1000)
{
elog(NOTICE, "LockReleaseAll: xid loop detected, giving up");
nleft = 0;
break;
}
/* ---------------------------
* XXX Here we assume the shared memory queue is circular and
* that we know its internal structure. Should have some sort of
......@@ -1176,72 +1280,73 @@ LockReleaseAll(LOCKMETHOD lockmethod, SHM_QUEUE *lockQueue)
done = (xidLook->queue.next == end);
lock = (LOCK *) MAKE_PTR(xidLook->tag.lock);
LOCK_PRINT("LockReleaseAll", (&lock->tag), 0);
#ifdef USER_LOCKS
xidtag_lockmethod = XIDENT_LOCKMETHOD(*xidLook);
if ((xidtag_lockmethod == lockmethod) || (trace_flag >= 2)) {
XID_PRINT("LockReleaseAll", xidLook);
LOCK_PRINT("LockReleaseAll", lock, 0);
}
/*
* Sometimes the queue appears to be messed up.
*/
if (count++ > 2000)
{
elog(NOTICE, "LockReleaseAll: xid loop detected, giving up");
nskip = 0;
break;
#ifdef USE_XIDTAG_LOCKMETHOD
if (xidtag_lockmethod != LOCK_LOCKMETHOD(*lock))
elog(NOTICE, "LockReleaseAll: xid/lock method mismatch: %d != %d",
xidtag_lockmethod, lock->tag.lockmethod);
#endif
if ((xidtag_lockmethod != lockmethod) && (trace_flag >= 2)) {
TPRINTF(trace_flag, "LockReleaseAll: skipping other table");
nleft++;
goto next_item;
}
Assert(lock->nHolding > 0);
Assert(lock->nActive > 0);
Assert(lock->nActive <= lock->nHolding);
Assert(xidLook->nHolding >= 0);
Assert(xidLook->nHolding <= lock->nHolding);
#ifdef USER_LOCKS
if (is_user_lock_table)
{
if ((xidLook->tag.pid == 0) || (xidLook->tag.xid != 0))
{
#ifdef USER_LOCKS_DEBUG
elog(NOTICE, "LockReleaseAll: skip normal lock [%d,%d,%d]",
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
#endif
nskip++;
TPRINTF(TRACE_USERLOCKS,
"LockReleaseAll: skiping normal lock [%d,%d,%d]",
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
nleft++;
goto next_item;
}
if (xidLook->tag.pid != MyProcPid)
{
/* This should never happen */
#ifdef USER_LOCKS_DEBUG
/* Should never happen */
elog(NOTICE,
"LockReleaseAll: skip other pid [%u,%u] [%d,%d,%d]",
"LockReleaseAll: INVALID PID: [%u,%u] [%d,%d,%d]",
lock->tag.tupleId.ip_posid,
((lock->tag.tupleId.ip_blkid.bi_hi << 16) +
lock->tag.tupleId.ip_blkid.bi_lo),
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
#endif
nskip++;
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
nleft++;
goto next_item;
}
#ifdef USER_LOCKS_DEBUG
elog(NOTICE,
"LockReleaseAll: release user lock [%u,%u] [%d,%d,%d]",
lock->tag.tupleId.ip_posid,
((lock->tag.tupleId.ip_blkid.bi_hi << 16) +
lock->tag.tupleId.ip_blkid.bi_lo),
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
#endif
TPRINTF(TRACE_USERLOCKS,
"LockReleaseAll: releasing user lock [%u,%u] [%d,%d,%d]",
lock->tag.tupleId.ip_posid,
((lock->tag.tupleId.ip_blkid.bi_hi << 16) +
lock->tag.tupleId.ip_blkid.bi_lo),
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
}
else
{
if ((xidLook->tag.pid != 0) || (xidLook->tag.xid == 0))
/* Can't check xidLook->tag.xid, can be 0 also for normal locks */
if (xidLook->tag.pid != 0)
{
#ifdef USER_LOCKS_DEBUG
elog(NOTICE,
"LockReleaseAll: skip user lock [%u,%u] [%d,%d,%d]",
lock->tag.tupleId.ip_posid,
((lock->tag.tupleId.ip_blkid.bi_hi << 16) +
lock->tag.tupleId.ip_blkid.bi_lo),
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
#endif
nskip++;
TPRINTF(TRACE_LOCKS,
"LockReleaseAll: skiping user lock [%u,%u] [%d,%d,%d]",
lock->tag.tupleId.ip_posid,
((lock->tag.tupleId.ip_blkid.bi_hi << 16) +
lock->tag.tupleId.ip_blkid.bi_lo),
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
nleft++;
goto next_item;
}
#ifdef USER_LOCKS_DEBUG
elog(NOTICE, "LockReleaseAll: release normal lock [%d,%d,%d]",
xidLook->tag.lock, xidLook->tag.pid, xidLook->tag.xid);
#endif
}
#endif
......@@ -1251,16 +1356,20 @@ LockReleaseAll(LOCKMETHOD lockmethod, SHM_QUEUE *lockQueue)
*/
if (lock->nHolding != xidLook->nHolding)
{
lock->nHolding -= xidLook->nHolding;
lock->nActive -= xidLook->nHolding;
Assert(lock->nActive >= 0);
for (i = 1; i <= numLockModes; i++)
{
Assert(xidLook->holders[i] >= 0);
lock->holders[i] -= xidLook->holders[i];
lock->activeHolders[i] -= xidLook->holders[i];
Assert((lock->holders[i] >= 0) \
&& (lock->activeHolders[i] >= 0));
if (!lock->activeHolders[i])
lock->mask &= BITS_OFF[i];
}
lock->nHolding -= xidLook->nHolding;
lock->nActive -= xidLook->nHolding;
Assert((lock->nHolding >= 0) && (lock->nActive >= 0));
Assert(lock->nActive <= lock->nHolding);
}
else
{
......@@ -1270,16 +1379,30 @@ LockReleaseAll(LOCKMETHOD lockmethod, SHM_QUEUE *lockQueue)
* --------------
*/
lock->nHolding = 0;
/* Fix the lock status, just for next LOCK_PRINT message. */
for (i=1; i<=numLockModes; i++) {
Assert(lock->holders[i] == lock->activeHolders[i]);
lock->holders[i] = lock->activeHolders[i] = 0;
}
}
LOCK_PRINT("LockReleaseAll: updated", lock, 0);
/*
* Remove the xid from the process lock queue
*/
SHMQueueDelete(&xidLook->queue);
/* ----------------
* always remove the xidLookup entry, we're done with it now
* ----------------
*/
#ifdef USER_LOCKS
SHMQueueDelete(&xidLook->queue);
#endif
if ((!hash_search(lockMethodTable->xidHash, (Pointer) xidLook, HASH_REMOVE, &found))
|| !found)
XID_PRINT("LockReleaseAll: deleting", xidLook);
result = (XIDLookupEnt *) hash_search(lockMethodTable->xidHash,
(Pointer) xidLook,
HASH_REMOVE,
&found);
if (!result || !found)
{
SpinRelease(masterLock);
elog(NOTICE, "LockReleaseAll: xid table corrupted");
......@@ -1293,10 +1416,11 @@ LockReleaseAll(LOCKMETHOD lockmethod, SHM_QUEUE *lockQueue)
* the last lock.
* --------------------
*/
LOCK_PRINT("LockReleaseAll: deleting", lock, 0);
Assert(lockMethodTable->lockHash->hash == tag_hash);
lock = (LOCK *)
hash_search(lockMethodTable->lockHash, (Pointer) &(lock->tag), HASH_REMOVE, &found);
lock = (LOCK *) hash_search(lockMethodTable->lockHash,
(Pointer) &(lock->tag),
HASH_REMOVE, &found);
if ((!lock) || (!found))
{
SpinRelease(masterLock);
......@@ -1324,15 +1448,18 @@ next_item:
SHMQueueFirst(&xidLook->queue, (Pointer *) &tmp, &tmp->queue);
xidLook = tmp;
}
SpinRelease(masterLock);
#ifdef USER_LOCKS
/*
* Reinitialize the queue only if nothing has been left in.
*/
if (nskip == 0)
#endif
if (nleft == 0) {
TPRINTF(trace_flag, "LockReleaseAll: reinitializing lockQueue");
SHMQueueInit(lockQueue);
}
SpinRelease(masterLock);
TPRINTF(trace_flag, "LockReleaseAll: done");
return TRUE;
}
......@@ -1420,7 +1547,7 @@ DeadLockCheck(SHM_QUEUE *lockQueue, LOCK *findlock, bool skip_check)
checked_procs[0] = MyProc;
nprocs = 1;
lockMethodTable = LockMethodTable[1];
lockMethodTable = LockMethodTable[DEFAULT_LOCKMETHOD];
xidTable = lockMethodTable->xidHash;
MemSet(&item, 0, XID_TAGSIZE);
......@@ -1456,7 +1583,7 @@ DeadLockCheck(SHM_QUEUE *lockQueue, LOCK *findlock, bool skip_check)
done = (xidLook->queue.next == end);
lock = (LOCK *) MAKE_PTR(xidLook->tag.lock);
LOCK_PRINT("DeadLockCheck", (&lock->tag), 0);
LOCK_PRINT("DeadLockCheck", lock, 0);
/*
* This is our only check to see if we found the lock we want.
......@@ -1560,9 +1687,190 @@ DeadLockCheck(SHM_QUEUE *lockQueue, LOCK *findlock, bool skip_check)
return false;
}
/*
* Return an array with the pids of all processes owning a lock.
* This works only for user locks because normal locks have no
* pid information in the corresponding XIDLookupEnt.
*/
ArrayType *
LockOwners(LOCKMETHOD lockmethod, LOCKTAG *locktag)
{
XIDLookupEnt *xidLook = NULL;
SPINLOCK masterLock;
LOCK *lock;
SHMEM_OFFSET lock_offset;
int count = 0;
LOCKMETHODTABLE *lockMethodTable;
HTAB *xidTable;
bool found;
int ndims,
nitems,
hdrlen,
size;
int lbounds[1],
hbounds[1];
ArrayType *array;
int *data_ptr;
/* Assume that no one will modify the result */
static int empty_array[] = { 20, 1, 0, 0, 0 };
#ifdef USER_LOCKS
int is_user_lock;
is_user_lock = (lockmethod == USER_LOCKMETHOD);
if (is_user_lock)
{
TPRINTF(TRACE_USERLOCKS, "LockOwners: user lock tag [%u,%u]",
locktag->tupleId.ip_posid,
((locktag->tupleId.ip_blkid.bi_hi << 16) +
locktag->tupleId.ip_blkid.bi_lo));
}
#endif
/* This must be changed when short term locks will be used */
locktag->lockmethod = lockmethod;
Assert((lockmethod >= MIN_LOCKMETHOD) && (lockmethod < NumLockMethods));
lockMethodTable = LockMethodTable[lockmethod];
if (!lockMethodTable)
{
elog(NOTICE, "lockMethodTable is null in LockOwners");
return ((ArrayType *) &empty_array);
}
if (LockingIsDisabled)
{
return ((ArrayType *) &empty_array);
}
masterLock = lockMethodTable->ctl->masterLock;
SpinAcquire(masterLock);
/*
* Find a lock with this tag
*/
Assert(lockMethodTable->lockHash->hash == tag_hash);
lock = (LOCK *) hash_search(lockMethodTable->lockHash, (Pointer) locktag,
HASH_FIND, &found);
/*
* let the caller print its own error message, too. Do not elog(WARN).
*/
if (!lock)
{
SpinRelease(masterLock);
elog(NOTICE, "LockOwners: locktable corrupted");
return ((ArrayType *) &empty_array);
}
if (!found)
{
SpinRelease(masterLock);
#ifdef USER_LOCKS
if (is_user_lock) {
TPRINTF(TRACE_USERLOCKS, "LockOwners: no lock with this tag");
return ((ArrayType *) &empty_array);
}
#endif
elog(NOTICE, "LockOwners: locktable lookup failed, no lock");
return ((ArrayType *) &empty_array);
}
LOCK_PRINT("LockOwners: found", lock, 0);
Assert((lock->nHolding > 0) && (lock->nActive > 0));
Assert(lock->nActive <= lock->nHolding);
lock_offset = MAKE_OFFSET(lock);
/* Construct a 1-dimensional array */
ndims = 1;
hdrlen = ARR_OVERHEAD(ndims);
lbounds[0] = 0;
hbounds[0] = lock->nActive;
size = hdrlen + sizeof(int) * hbounds[0];
array = (ArrayType *) palloc(size);
MemSet(array, 0, size);
memmove((char *) array, (char *) &size, sizeof(int));
memmove((char *) ARR_NDIM_PTR(array), (char *) &ndims, sizeof(int));
memmove((char *) ARR_DIMS(array), (char *) hbounds, ndims * sizeof(int));
memmove((char *) ARR_LBOUND(array), (char *) lbounds, ndims * sizeof(int));
SET_LO_FLAG(false, array);
data_ptr = (int *) ARR_DATA_PTR(array);
xidTable = lockMethodTable->xidHash;
hash_seq(NULL);
nitems = 0;
while ((xidLook = (XIDLookupEnt *)hash_seq(xidTable)) &&
(xidLook != (XIDLookupEnt *)TRUE)) {
if (count++ > 1000) {
elog(NOTICE,"LockOwners: possible loop, giving up");
break;
}
if (xidLook->tag.pid == 0) {
XID_PRINT("LockOwners: no pid", xidLook);
continue;
}
if (!xidLook->tag.lock) {
XID_PRINT("LockOwners: NULL LOCK", xidLook);
continue;
}
if (xidLook->tag.lock != lock_offset) {
XID_PRINT("LockOwners: different lock", xidLook);
continue;
}
if (LOCK_LOCKMETHOD(*lock) != lockmethod) {
XID_PRINT("LockOwners: other table", xidLook);
continue;
}
if (xidLook->nHolding <= 0) {
XID_PRINT("LockOwners: not holding", xidLook);
continue;
}
if (nitems >= hbounds[0]) {
elog(NOTICE,"LockOwners: array size exceeded");
break;
}
/*
* Check that the holding process is still alive by sending
* him an unused (ignored) signal. If the kill fails the
* process is not alive.
*/
if ((xidLook->tag.pid != MyProcPid) \
&& (kill(xidLook->tag.pid, SIGCHLD)) != 0)
{
/* Return a negative pid to signal that process is dead */
data_ptr[nitems++] = - (xidLook->tag.pid);
XID_PRINT("LockOwners: not alive", xidLook);
/* XXX - TODO: remove this entry and update lock stats */
continue;
}
/* Found a process holding the lock */
XID_PRINT("LockOwners: holding", xidLook);
data_ptr[nitems++] = xidLook->tag.pid;
}
SpinRelease(masterLock);
/* Adjust the actual size of the array */
hbounds[0] = nitems;
size = hdrlen + sizeof(int) * hbounds[0];
memmove((char *) array, (char *) &size, sizeof(int));
memmove((char *) ARR_DIMS(array), (char *) hbounds, ndims * sizeof(int));
return (array);
}
#ifdef DEADLOCK_DEBUG
/*
* Dump all locks. Must have already acquired the masterLock.
* Dump all locks in the proc->lockQueue. Must have already acquired
* the masterLock.
*/
void
DumpLocks()
......@@ -1577,9 +1885,8 @@ DumpLocks()
SPINLOCK masterLock;
int numLockModes;
LOCK *lock;
count;
int lockmethod = 1;
int count = 0;
int lockmethod = DEFAULT_LOCKMETHOD;
LOCKMETHODTABLE *lockMethodTable;
ShmemPIDLookup(MyProcPid, &location);
......@@ -1604,11 +1911,18 @@ DumpLocks()
SHMQueueFirst(lockQueue, (Pointer *) &xidLook, &xidLook->queue);
end = MAKE_OFFSET(lockQueue);
LOCK_DUMP("DumpLocks", MyProc->waitLock, 0);
XID_PRINT("DumpLocks", xidLook);
if (MyProc->waitLock) {
LOCK_PRINT_AUX("DumpLocks: waiting on", MyProc->waitLock, 0);
}
for (count = 0;;)
for (;;)
{
if (count++ > 2000)
{
elog(NOTICE, "DumpLocks: xid loop detected, giving up");
break;
}
/* ---------------------------
* XXX Here we assume the shared memory queue is circular and
* that we know its internal structure. Should have some sort of
......@@ -1618,19 +1932,68 @@ DumpLocks()
done = (xidLook->queue.next == end);
lock = (LOCK *) MAKE_PTR(xidLook->tag.lock);
LOCK_DUMP("DumpLocks", lock, 0);
if (count++ > 2000)
{
elog(NOTICE, "DumpLocks: xid loop detected, giving up");
break;
}
XID_PRINT_AUX("DumpLocks", xidLook);
LOCK_PRINT_AUX("DumpLocks", lock, 0);
if (done)
break;
SHMQueueFirst(&xidLook->queue, (Pointer *) &tmp, &tmp->queue);
xidLook = tmp;
}
}
/*
* Dump all postgres locks. Must have already acquired the masterLock.
*/
void
DumpAllLocks()
{
SHMEM_OFFSET location;
PROC *proc;
XIDLookupEnt *xidLook = NULL;
LOCK *lock;
int pid;
int count = 0;
int lockmethod = DEFAULT_LOCKMETHOD;
LOCKMETHODTABLE *lockMethodTable;
HTAB *xidTable;
pid = getpid();
ShmemPIDLookup(pid,&location);
if (location == INVALID_OFFSET)
return;
proc = (PROC *) MAKE_PTR(location);
if (proc != MyProc)
return;
Assert(lockmethod < NumLockMethods);
lockMethodTable = LockMethodTable[lockmethod];
if (!lockMethodTable)
return;
xidTable = lockMethodTable->xidHash;
if (MyProc->waitLock) {
LOCK_PRINT_AUX("DumpAllLocks: waiting on", MyProc->waitLock,0);
}
hash_seq(NULL);
while ((xidLook = (XIDLookupEnt *)hash_seq(xidTable)) &&
(xidLook != (XIDLookupEnt *)TRUE)) {
XID_PRINT_AUX("DumpAllLocks", xidLook);
if (xidLook->tag.lock) {
lock = (LOCK *) MAKE_PTR(xidLook->tag.lock);
LOCK_PRINT_AUX("DumpAllLocks", lock, 0);
} else {
elog(DEBUG, "DumpAllLocks: xidLook->tag.lock = NULL");
}
if (count++ > 2000) {
elog(NOTICE,"DumpAllLocks: possible loop, giving up");
break;
}
}
}
#endif
src/backend/storage/lmgr/multi.c
View file @ 7dbcf31b
......@@ -12,7 +12,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/Attic/multi.c,v 1.22 1998/08/19 02:02:44 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/Attic/multi.c,v 1.23 1998/08/25 21:20:28 scrappy Exp $
*
* NOTES:
* (1) The lock.c module assumes that the caller here is doing
......@@ -29,12 +29,10 @@
#include "utils/rel.h"
#include "miscadmin.h" /* MyDatabaseId */
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);
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);
#ifdef LowLevelLocking
......@@ -130,6 +128,7 @@ static int MultiPrios[] = {
* lock table is ONE lock table, not three.
*/
LOCKMETHOD MultiTableId = (LOCKMETHOD) NULL;
LOCKMETHOD LongTermTableId = (LOCKMETHOD) NULL;
#ifdef NOT_USED
LOCKMETHOD ShortTermTableId = (LOCKMETHOD) NULL;
#endif
......@@ -150,12 +149,25 @@ InitMultiLevelLocks()
/* -----------------------
* No short term lock table for now. -Jeff 15 July 1991
*
* ShortTermTableId = LockTableRename(lockmethod);
* 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;
}
......
src/backend/storage/lmgr/proc.c
View file @ 7dbcf31b
......@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.40 1998/07/27 19:38:15 vadim Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.41 1998/08/25 21:20:29 scrappy Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -46,7 +46,7 @@
* This is so that we can support more backends. (system-wide semaphore
* sets run out pretty fast.) -ay 4/95
*
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.40 1998/07/27 19:38:15 vadim Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.41 1998/08/25 21:20:29 scrappy Exp $
*/
#include <sys/time.h>
#include <unistd.h>
......@@ -75,10 +75,13 @@
#include "storage/shmem.h"
#include "storage/spin.h"
#include "storage/proc.h"
#include "utils/trace.h"
static void HandleDeadLock(int sig);
static PROC *ProcWakeup(PROC *proc, int errType);
#define DeadlockCheckTimer pg_options[OPT_DEADLOCKTIMEOUT]
/* --------------------
* Spin lock for manipulating the shared process data structure:
* ProcGlobal.... Adding an extra spin lock seemed like the smallest
......@@ -247,10 +250,7 @@ InitProcess(IPCKey key)
*/
SpinRelease(ProcStructLock);
MyProc->pid = 0;
#if 0
MyProc->pid = MyProcPid;
#endif
MyProc->xid = InvalidTransactionId;
#ifdef LowLevelLocking
MyProc->xmin = InvalidTransactionId;
......@@ -361,10 +361,13 @@ ProcKill(int exitStatus, int pid)
* ---------------
*/
ProcReleaseSpins(proc);
LockReleaseAll(1, &proc->lockQueue);
LockReleaseAll(DEFAULT_LOCKMETHOD, &proc->lockQueue);
#ifdef USER_LOCKS
LockReleaseAll(0, &proc->lockQueue);
/*
* Assume we have a second lock table.
*/
LockReleaseAll(USER_LOCKMETHOD, &proc->lockQueue);
#endif
/* ----------------
......@@ -437,11 +440,12 @@ ProcQueueInit(PROC_QUEUE *queue)
* NOTES: The process queue is now a priority queue for locking.
*/
int
ProcSleep(PROC_QUEUE *waitQueue,
ProcSleep(PROC_QUEUE *waitQueue, /* lock->waitProcs */
SPINLOCK spinlock,
int token,
int token, /* lockmode */
int prio,
LOCK *lock)
LOCK *lock,
TransactionId xid) /* needed by user locks, see below */
{
int i;
PROC *proc;
......@@ -470,7 +474,6 @@ ProcSleep(PROC_QUEUE *waitQueue,
proc = (PROC *) MAKE_PTR(waitQueue->links.prev);
/* If we are a reader, and they are writers, skip past them */
for (i = 0; i < waitQueue->size && proc->prio > prio; i++)
proc = (PROC *) MAKE_PTR(proc->links.prev);
......@@ -482,12 +485,22 @@ ProcSleep(PROC_QUEUE *waitQueue,
MyProc->token = token;
MyProc->waitLock = lock;
#ifdef USER_LOCKS
/* -------------------
* Currently, we only need this for the ProcWakeup routines.
* This must be 0 for user lock, so we can't just use the value
* from GetCurrentTransactionId().
* -------------------
*/
TransactionIdStore(xid, &MyProc->xid);
#else
#ifndef LowLevelLocking
/* -------------------
* currently, we only need this for the ProcWakeup routines
* -------------------
*/
TransactionIdStore((TransactionId) GetCurrentTransactionId(), &MyProc->xid);
#endif
#endif
/* -------------------
......@@ -510,7 +523,8 @@ ProcSleep(PROC_QUEUE *waitQueue,
* --------------
*/
MemSet(&timeval, 0, sizeof(struct itimerval));
timeval.it_value.tv_sec = DEADLOCK_CHECK_TIMER;
timeval.it_value.tv_sec = \
(DeadlockCheckTimer ? DeadlockCheckTimer : DEADLOCK_CHECK_TIMER);
do
{
......@@ -525,7 +539,8 @@ ProcSleep(PROC_QUEUE *waitQueue,
* the semaphore implementation.
* --------------
*/
IpcSemaphoreLock(MyProc->sem.semId, MyProc->sem.semNum, IpcExclusiveLock);
IpcSemaphoreLock(MyProc->sem.semId, MyProc->sem.semNum,
IpcExclusiveLock);
} while (MyProc->errType == STATUS_NOT_FOUND); /* sleep after deadlock
* check */
......@@ -534,8 +549,6 @@ ProcSleep(PROC_QUEUE *waitQueue,
* ---------------
*/
timeval.it_value.tv_sec = 0;
if (setitimer(ITIMER_REAL, &timeval, &dummy))
elog(FATAL, "ProcSleep: Unable to diable timer for process wakeup");
......@@ -546,6 +559,11 @@ ProcSleep(PROC_QUEUE *waitQueue,
*/
SpinAcquire(spinlock);
#ifdef LOCK_MGR_DEBUG
/* Just to get meaningful debug messages from DumpLocks() */
MyProc->waitLock = (LOCK *)NULL;
#endif
return (MyProc->errType);
}
......@@ -589,17 +607,39 @@ ProcLockWakeup(PROC_QUEUE *queue, LOCKMETHOD lockmethod, LOCK *lock)
{
PROC *proc;
int count;
int trace_flag;
int last_locktype = -1;
int queue_size = queue->size;
Assert(queue->size >= 0);
if (!queue->size)
return (STATUS_NOT_FOUND);
proc = (PROC *) MAKE_PTR(queue->links.prev);
count = 0;
while ((LockResolveConflicts(lockmethod,
while ((queue_size--) && (proc))
{
/*
* This proc will conflict as the previous one did, don't even try.
*/
if (proc->token == last_locktype)
{
continue;
}
/*
* This proc conflicts with locks held by others, ignored.
*/
if (LockResolveConflicts(lockmethod,
lock,
proc->token,
proc->xid) == STATUS_OK))
{
proc->xid,
(XIDLookupEnt *) NULL) != STATUS_OK)
{
last_locktype = proc->token;
continue;
}
/*
* there was a waiting process, grant it the lock before waking it
......@@ -608,24 +648,34 @@ ProcLockWakeup(PROC_QUEUE *queue, LOCKMETHOD lockmethod, LOCK *lock)
* time that the awoken process begins executing again.
*/
GrantLock(lock, proc->token);
queue->size--;
/*
* ProcWakeup removes proc from the lock waiting process queue and
* returns the next proc in chain.
*/
proc = ProcWakeup(proc, NO_ERROR);
count++;
if (!proc || queue->size == 0)
break;
queue->size--;
proc = ProcWakeup(proc, NO_ERROR);
}
Assert(queue->size >= 0);
if (count)
return (STATUS_OK);
else
else {
/* Something is still blocking us. May have deadlocked. */
trace_flag = (lock->tag.lockmethod == USER_LOCKMETHOD) ? \
TRACE_USERLOCKS : TRACE_LOCKS;
TPRINTF(trace_flag,
"ProcLockWakeup: lock(%x) can't wake up any process",
MAKE_OFFSET(lock));
#ifdef DEADLOCK_DEBUG
if (pg_options[trace_flag] >= 2)
DumpAllLocks();
#endif
return (STATUS_NOT_FOUND);
}
}
void
......@@ -685,7 +735,7 @@ HandleDeadLock(int sig)
}
#ifdef DEADLOCK_DEBUG
DumpLocks();
DumpAllLocks();
#endif
if (!DeadLockCheck(&(MyProc->lockQueue), MyProc->waitLock, true))
......@@ -711,7 +761,8 @@ HandleDeadLock(int sig)
* I was awoken by a signal, not by someone unlocking my semaphore.
* ------------------
*/
IpcSemaphoreUnlock(MyProc->sem.semId, MyProc->sem.semNum, IpcExclusiveLock);
IpcSemaphoreUnlock(MyProc->sem.semId, MyProc->sem.semNum,
IpcExclusiveLock);
/* -------------
* Set MyProc->errType to STATUS_ERROR so that we abort after
......
src/include/storage/lock.h
View file @ 7dbcf31b
......@@ -6,7 +6,7 @@
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: lock.h,v 1.16 1998/08/01 15:26:37 vadim Exp $
* $Id: lock.h,v 1.17 1998/08/25 21:20:31 scrappy Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -15,6 +15,8 @@
#include <storage/shmem.h>
#include <storage/itemptr.h>
#include <storage/sinvaladt.h>
#include <utils/array.h>
extern SPINLOCK LockMgrLock;
typedef int MASK;
......@@ -32,7 +34,7 @@ typedef int MASK;
* NLOCKENTS - The maximum number of lock entries in the lock table.
* ----------------------
*/
#define NBACKENDS 50
#define NBACKENDS MaxBackendId
#define NLOCKS_PER_XACT 40
#define NLOCKENTS NLOCKS_PER_XACT*NBACKENDS
......@@ -51,9 +53,14 @@ typedef int LOCKMETHOD;
* CreateSpinLocks() or the number of shared memory locations allocated
* for lock table spin locks in the case of machines with TAS instructions.
*/
#define MAX_LOCK_METHODS 2
#define MAX_LOCK_METHODS 3
#define INVALID_TABLEID 0
#define INVALID_TABLEID 0
#define INVALID_LOCKMETHOD INVALID_TABLEID
#define DEFAULT_LOCKMETHOD 1
#define USER_LOCKMETHOD 2
#define MIN_LOCKMETHOD DEFAULT_LOCKMETHOD
/*typedef struct LOCK LOCK; */
......@@ -63,9 +70,11 @@ typedef struct LTAG
Oid relId;
Oid dbId;
ItemPointerData tupleId;
uint16 lockmethod; /* needed by user locks */
} LOCKTAG;
#define TAGSIZE (sizeof(LOCKTAG))
#define LOCKTAG_LOCKMETHOD(locktag) ((locktag).lockmethod)
/* This is the control structure for a lock table. It
* lives in shared memory:
......@@ -143,8 +152,18 @@ typedef struct XIDTAG
SHMEM_OFFSET lock;
int pid;
TransactionId xid;
#ifdef USE_XIDTAG_LOCKMETHOD
uint16 lockmethod; /* for debug or consistency checking */
#endif
} XIDTAG;
#ifdef USE_XIDTAG_LOCKMETHOD
#define XIDTAG_LOCKMETHOD(xidtag) ((xidtag).lockmethod)
#else
#define XIDTAG_LOCKMETHOD(xidtag) \
(((LOCK*) MAKE_PTR((xidtag).lock))->tag.lockmethod)
#endif
typedef struct XIDLookupEnt
{
/* tag */
......@@ -157,6 +176,7 @@ typedef struct XIDLookupEnt
} XIDLookupEnt;
#define XID_TAGSIZE (sizeof(XIDTAG))
#define XIDENT_LOCKMETHOD(xident) (XIDTAG_LOCKMETHOD((xident).tag))
/* originally in procq.h */
typedef struct PROC_QUEUE
......@@ -191,14 +211,16 @@ typedef struct LOCK
int nActive;
} LOCK;
#define LockGetLock_nHolders(l) l->nHolders
#define LOCK_LOCKMETHOD(lock) (LOCKTAG_LOCKMETHOD((lock).tag))
#define LockGetLock_nHolders(l) l->nHolders
#ifdef NOT_USED
#define LockDecrWaitHolders(lock, lockmode) \
( \
lock->nHolding--, \
lock->holders[lockmode]-- \
)
#endif
#define LockLockTable() SpinAcquire(LockMgrLock);
#define UnlockLockTable() SpinRelease(LockMgrLock);
......@@ -209,23 +231,27 @@ extern SPINLOCK LockMgrLock;
*/
extern void InitLocks(void);
extern void LockDisable(int status);
extern LOCKMETHOD
LockMethodTableInit(char *tabName, MASK *conflictsP, int *prioP,
int numModes);
extern bool LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode);
extern int
LockResolveConflicts(LOCKMETHOD lockmethod, LOCK *lock, LOCKMODE lockmode,
TransactionId xid);
extern bool LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag, LOCKMODE lockmode);
extern LOCKMETHOD LockMethodTableInit(char *tabName, MASK *conflictsP,
int *prioP, int numModes);
extern LOCKMETHOD LockMethodTableRename(LOCKMETHOD lockmethod);
extern bool LockAcquire(LOCKMETHOD lockmethod, LOCKTAG *locktag,
LOCKMODE lockmode);
extern int LockResolveConflicts(LOCKMETHOD lockmethod, LOCK *lock,
LOCKMODE lockmode, TransactionId xid,
XIDLookupEnt *xidentP);
extern bool LockRelease(LOCKMETHOD lockmethod, LOCKTAG *locktag,
LOCKMODE lockmode);
extern void GrantLock(LOCK *lock, LOCKMODE lockmode);
extern bool LockReleaseAll(LOCKMETHOD lockmethod, SHM_QUEUE *lockQueue);
extern int LockShmemSize(void);
extern bool LockingDisabled(void);
extern bool DeadLockCheck(SHM_QUEUE *lockQueue, LOCK *findlock, bool skip_check);
extern bool DeadLockCheck(SHM_QUEUE *lockQueue, LOCK *findlock,
bool skip_check);
ArrayType* LockOwners(LOCKMETHOD lockmethod, LOCKTAG *locktag);
#ifdef DEADLOCK_DEBUG
extern void DumpLocks(void);
extern void DumpAllLocks(void);
#endif
#endif /* LOCK_H */
src/include/storage/proc.h
View file @ 7dbcf31b
......@@ -6,7 +6,7 @@
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: proc.h,v 1.13 1998/07/27 19:38:38 vadim Exp $
* $Id: proc.h,v 1.14 1998/08/25 21:20:32 scrappy Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -105,10 +105,10 @@ extern bool ProcRemove(int pid);
/* make static in storage/lmgr/proc.c -- jolly */
extern void ProcQueueInit(PROC_QUEUE *queue);
extern int
ProcSleep(PROC_QUEUE *queue, SPINLOCK spinlock, int token,
int prio, LOCK *lock);
extern int ProcLockWakeup(PROC_QUEUE *queue, LOCKMETHOD lockmethod, LOCK *lock);
extern int ProcSleep(PROC_QUEUE *queue, SPINLOCK spinlock, int token,
int prio, LOCK *lock, TransactionId xid);
extern int ProcLockWakeup(PROC_QUEUE *queue, LOCKMETHOD lockmethod,
LOCK *lock);
extern void ProcAddLock(SHM_QUEUE *elem);
extern void ProcReleaseSpins(PROC *proc);
extern void ProcFreeAllSemaphores(void);
......
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