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Rename BindingTable to ShmemIndex.

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This commit is contained in:
Bruce Momjian
1998-06-27 15:47:48 +00:00
parent 7487a82667
commit 54aabaa800
8 changed files with 130 additions and 130 deletions
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10
src/backend/storage/buffer/buf_init.c
View File

@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.17 1998/01/07 21:04:46 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.18 1998/06/27 15:47:43 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -277,14 +277,14 @@ BufferShmemSize()
nbuckets = 1 << (int) my_log2((NBuffers - 1) / DEF_FFACTOR + 1);
nsegs = 1 << (int) my_log2((nbuckets - 1) / DEF_SEGSIZE + 1);
/* size of shmem binding table */
size += MAXALIGN(my_log2(BTABLE_SIZE) * sizeof(void *)); /* HTAB->dir */
/* size of shmem index table */
size += MAXALIGN(my_log2(SHMEM_INDEX_SIZE) * sizeof(void *)); /* HTAB->dir */
size += MAXALIGN(sizeof(HHDR)); /* HTAB->hctl */
size += MAXALIGN(DEF_SEGSIZE * sizeof(SEGMENT));
size += BUCKET_ALLOC_INCR *
(MAXALIGN(sizeof(BUCKET_INDEX)) +
MAXALIGN(BTABLE_KEYSIZE) +
MAXALIGN(BTABLE_DATASIZE));
MAXALIGN(SHMEM_INDEX_KEYSIZE) +
MAXALIGN(SHMEM_INDEX_DATASIZE));
/* size of buffer descriptors */
size += MAXALIGN((NBuffers + 1) * sizeof(BufferDesc));

4
src/backend/storage/ipc/ipci.c
View File

@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/ipci.c,v 1.14 1998/06/27 04:53:35 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/ipci.c,v 1.15 1998/06/27 15:47:44 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -83,7 +83,7 @@ CreateSharedMemoryAndSemaphores(IPCKey key)
IPCKeyGetBufferMemoryKey(key), size);
}
ShmemCreate(IPCKeyGetBufferMemoryKey(key), size);
ShmemBindingTableReset();
ShmemIndexReset();
InitShmem(key, size);
InitBufferPool(key);

188
src/backend/storage/ipc/shmem.c
View File

@@ -7,14 +7,14 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/shmem.c,v 1.24 1998/06/27 14:06:41 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/shmem.c,v 1.25 1998/06/27 15:47:44 momjian Exp $
*
*-------------------------------------------------------------------------
*/
/*
* POSTGRES processes share one or more regions of shared memory.
* The shared memory is created by a postmaster and is "attached to"
* by each of the backends. The routines in this file are used for
* The shared memory is created by a postmaster and is inherited
* by each backends via fork(). The routines in this file are used for
* allocating and binding to shared memory data structures.
*
* NOTES:
@@ -30,16 +30,16 @@
* it (assigned in the module that declares it).
*
* (b) During initialization, each module looks for its
* shared data structures in a hash table called the "Binding Table".
* shared data structures in a hash table called the "Shmem Index".
* If the data structure is not present, the caller can allocate
* a new one and initialize it. If the data structure is present,
* the caller "attaches" to the structure by initializing a pointer
* in the local address space.
* The binding table has two purposes: first, it gives us
* The shmem index has two purposes: first, it gives us
* a simple model of how the world looks when a backend process
* initializes. If something is present in the binding table,
* initializes. If something is present in the shmem index,
* it is initialized. If it is not, it is uninitialized. Second,
* the binding table allows us to allocate shared memory on demand
* the shmem index allows us to allocate shared memory on demand
* instead of trying to preallocate structures and hard-wire the
* sizes and locations in header files. If you are using a lot
* of shared memory in a lot of different places (and changing
@@ -54,7 +54,7 @@
* unnecessary.
*
* See InitSem() in sem.c for an example of how to use the
* binding table.
* shmem index.
*
*/
#include <stdio.h>
@@ -76,28 +76,28 @@ static unsigned long ShmemSize = 0; /* current size (and default) */
SPINLOCK ShmemLock; /* lock for shared memory allocation */
SPINLOCK BindingLock; /* lock for binding table access */
SPINLOCK ShmemIndexLock; /* lock for shmem index access */
static unsigned long *ShmemFreeStart = NULL; /* pointer to the OFFSET
* of first free shared
* memory */
static unsigned long *ShmemBindingTableOffset = NULL; /* start of the binding
static unsigned long *ShmemIndexOffset = NULL; /* start of the shmem index
* table (for bootstrap) */
static int ShmemBootstrap = FALSE; /* flag becomes true when shared
* mem is created by POSTMASTER */
static HTAB *BindingTable = NULL;
static HTAB *ShmemIndex = NULL;
/* ---------------------
* ShmemBindingTableReset() - Resets the binding table to NULL....
* ShmemIndexReset() - Resets the shmem index to NULL....
* useful when the postmaster destroys existing shared memory
* and creates all new segments after a backend crash.
* ----------------------
*/
void
ShmemBindingTableReset(void)
ShmemIndexReset(void)
{
BindingTable = (HTAB *) NULL;
ShmemIndex = (HTAB *) NULL;
}
/*
@@ -147,7 +147,7 @@ InitShmem(unsigned int key, unsigned int size)
HASHCTL info;
int hash_flags;
BindingEnt *result,
ShmemIndexEnt *result,
item;
bool found;
IpcMemoryId shmid;
@@ -178,15 +178,15 @@ InitShmem(unsigned int key, unsigned int size)
/* First long in shared memory is the count of available space */
ShmemFreeStart = (unsigned long *) ShmemBase;
/* next is a shmem pointer to the binding table */
ShmemBindingTableOffset = ShmemFreeStart + 1;
/* next is a shmem pointer to the shmem index */
ShmemIndexOffset = ShmemFreeStart + 1;
currFreeSpace +=
sizeof(ShmemFreeStart) + sizeof(ShmemBindingTableOffset);
sizeof(ShmemFreeStart) + sizeof(ShmemIndexOffset);
/*
* bootstrap initialize spin locks so we can start to use the
* allocator and binding table.
* allocator and shmem index.
*/
if (!InitSpinLocks(ShmemBootstrap, IPCKeyGetSpinLockSemaphoreKey(key)))
return (FALSE);
@@ -201,37 +201,37 @@ InitShmem(unsigned int key, unsigned int size)
/* if ShmemFreeStart is NULL, then the allocator won't work */
Assert(*ShmemFreeStart);
/* create OR attach to the shared memory binding table */
info.keysize = BTABLE_KEYSIZE;
info.datasize = BTABLE_DATASIZE;
/* create OR attach to the shared memory shmem index */
info.keysize = SHMEM_INDEX_KEYSIZE;
info.datasize = SHMEM_INDEX_DATASIZE;
hash_flags = (HASH_ELEM);
/* This will acquire the binding table lock, but not release it. */
BindingTable = ShmemInitHash("BindingTable",
BTABLE_SIZE, BTABLE_SIZE,
/* This will acquire the shmem index lock, but not release it. */
ShmemIndex = ShmemInitHash("ShmemIndex",
SHMEM_INDEX_SIZE, SHMEM_INDEX_SIZE,
&info, hash_flags);
if (!BindingTable)
if (!ShmemIndex)
{
elog(FATAL, "InitShmem: couldn't initialize Binding Table");
elog(FATAL, "InitShmem: couldn't initialize Shmem Index");
return (FALSE);
}
/*
* Now, check the binding table for an entry to the binding table. If
* Now, check the shmem index for an entry to the shmem index. If
* there is an entry there, someone else created the table. Otherwise,
* we did and we have to initialize it.
*/
MemSet(item.key, 0, BTABLE_KEYSIZE);
strncpy(item.key, "BindingTable", BTABLE_KEYSIZE);
MemSet(item.key, 0, SHMEM_INDEX_KEYSIZE);
strncpy(item.key, "ShmemIndex", SHMEM_INDEX_KEYSIZE);
result = (BindingEnt *)
hash_search(BindingTable, (char *) &item, HASH_ENTER, &found);
result = (ShmemIndexEnt *)
hash_search(ShmemIndex, (char *) &item, HASH_ENTER, &found);
if (!result)
{
elog(FATAL, "InitShmem: corrupted binding table");
elog(FATAL, "InitShmem: corrupted shmem index");
return (FALSE);
}
@@ -239,14 +239,14 @@ InitShmem(unsigned int key, unsigned int size)
{
/*
* bootstrapping shmem: we have to initialize the binding table
* bootstrapping shmem: we have to initialize the shmem index
* now.
*/
Assert(ShmemBootstrap);
result->location = MAKE_OFFSET(BindingTable->hctl);
*ShmemBindingTableOffset = result->location;
result->size = BTABLE_SIZE;
result->location = MAKE_OFFSET(ShmemIndex->hctl);
*ShmemIndexOffset = result->location;
result->size = SHMEM_INDEX_SIZE;
ShmemBootstrap = FALSE;
@@ -254,9 +254,9 @@ InitShmem(unsigned int key, unsigned int size)
else
Assert(!ShmemBootstrap);
/* now release the lock acquired in ShmemHashInit */
SpinRelease(BindingLock);
SpinRelease(ShmemIndexLock);
Assert(result->location == MAKE_OFFSET(BindingTable->hctl));
Assert(result->location == MAKE_OFFSET(ShmemIndex->hctl));
return (TRUE);
}
@@ -329,7 +329,7 @@ ShmemIsValid(unsigned long addr)
* for the structure before creating the structure itself.
*/
HTAB *
ShmemInitHash(char *name, /* table string name for binding */
ShmemInitHash(char *name, /* table string name for shmem index */
long init_size, /* initial size */
long max_size, /* max size of the table */
HASHCTL *infoP, /* info about key and bucket size */
@@ -348,12 +348,12 @@ ShmemInitHash(char *name, /* table string name for binding */
infoP->max_size = max_size;
hash_flags |= HASH_SHARED_MEM;
/* look it up in the binding table */
/* look it up in the shmem index */
location =
ShmemInitStruct(name, my_log2(max_size) + sizeof(HHDR), &found);
/*
* binding table is corrupted. Let someone else give the error
* shmem index is corrupted. Let someone else give the error
* message since they have more information
*/
if (location == NULL)
@@ -379,7 +379,7 @@ ShmemInitHash(char *name, /* table string name for binding */
* ShmemPIDLookup -- lookup process data structure using process id
*
* Returns: TRUE if no error. locationPtr is initialized if PID is
* found in the binding table.
* found in the shmem index.
*
* NOTES:
* only information about success or failure is the value of
@@ -388,23 +388,23 @@ ShmemInitHash(char *name, /* table string name for binding */
bool
ShmemPIDLookup(int pid, SHMEM_OFFSET *locationPtr)
{
BindingEnt *result,
ShmemIndexEnt *result,
item;
bool found;
Assert(BindingTable);
MemSet(item.key, 0, BTABLE_KEYSIZE);
Assert(ShmemIndex);
MemSet(item.key, 0, SHMEM_INDEX_KEYSIZE);
sprintf(item.key, "PID %d", pid);
SpinAcquire(BindingLock);
result = (BindingEnt *)
hash_search(BindingTable, (char *) &item, HASH_ENTER, &found);
SpinAcquire(ShmemIndexLock);
result = (ShmemIndexEnt *)
hash_search(ShmemIndex, (char *) &item, HASH_ENTER, &found);
if (!result)
{
SpinRelease(BindingLock);
elog(ERROR, "ShmemInitPID: BindingTable corrupted");
SpinRelease(ShmemIndexLock);
elog(ERROR, "ShmemInitPID: ShmemIndex corrupted");
return (FALSE);
}
@@ -414,39 +414,39 @@ ShmemPIDLookup(int pid, SHMEM_OFFSET *locationPtr)
else
result->location = *locationPtr;
SpinRelease(BindingLock);
SpinRelease(ShmemIndexLock);
return (TRUE);
}
/*
* ShmemPIDDestroy -- destroy binding table entry for process
* ShmemPIDDestroy -- destroy shmem index entry for process
* using process id
*
* Returns: offset of the process struct in shared memory or
* INVALID_OFFSET if not found.
*
* Side Effect: removes the entry from the binding table
* Side Effect: removes the entry from the shmem index
*/
SHMEM_OFFSET
ShmemPIDDestroy(int pid)
{
BindingEnt *result,
ShmemIndexEnt *result,
item;
bool found;
SHMEM_OFFSET location = 0;
Assert(BindingTable);
Assert(ShmemIndex);
MemSet(item.key, 0, BTABLE_KEYSIZE);
MemSet(item.key, 0, SHMEM_INDEX_KEYSIZE);
sprintf(item.key, "PID %d", pid);
SpinAcquire(BindingLock);
result = (BindingEnt *)
hash_search(BindingTable, (char *) &item, HASH_REMOVE, &found);
SpinAcquire(ShmemIndexLock);
result = (ShmemIndexEnt *)
hash_search(ShmemIndex, (char *) &item, HASH_REMOVE, &found);
if (found)
location = result->location;
SpinRelease(BindingLock);
SpinRelease(ShmemIndexLock);
if (!result)
{
@@ -473,33 +473,33 @@ ShmemPIDDestroy(int pid)
* table is returned.
*
* Returns: real pointer to the object. FoundPtr is TRUE if
* the object is already in the binding table (hence, already
* the object is already in the shmem index (hence, already
* initialized).
*/
long *
ShmemInitStruct(char *name, unsigned long size, bool *foundPtr)
{
BindingEnt *result,
ShmemIndexEnt *result,
item;
long *structPtr;
strncpy(item.key, name, BTABLE_KEYSIZE);
strncpy(item.key, name, SHMEM_INDEX_KEYSIZE);
item.location = BAD_LOCATION;
SpinAcquire(BindingLock);
SpinAcquire(ShmemIndexLock);
if (!BindingTable)
if (!ShmemIndex)
{
#ifdef USE_ASSERT_CHECKING
char *strname = "BindingTable";
char *strname = "ShmemIndex";
#endif
/*
* If the binding table doesnt exist, we fake it.
* If the shmem index doesnt exist, we fake it.
*
* If we are creating the first binding table, then let shmemalloc()
* If we are creating the first shmem index, then let shmemalloc()
* allocate the space for a new HTAB. Otherwise, find the old one
* and return that. Notice that the BindingLock is held until the
* binding table has been completely initialized.
* and return that. Notice that the ShmemIndexLock is held until the
* shmem index has been completely initialized.
*/
Assert(!strcmp(name, strname));
if (ShmemBootstrap)
@@ -511,41 +511,41 @@ ShmemInitStruct(char *name, unsigned long size, bool *foundPtr)
}
else
{
Assert(ShmemBindingTableOffset);
Assert(ShmemIndexOffset);
*foundPtr = TRUE;
return ((long *) MAKE_PTR(*ShmemBindingTableOffset));
return ((long *) MAKE_PTR(*ShmemIndexOffset));
}
}
else
{
/* look it up in the binding table */
result = (BindingEnt *)
hash_search(BindingTable, (char *) &item, HASH_ENTER, foundPtr);
/* look it up in the shmem index */
result = (ShmemIndexEnt *)
hash_search(ShmemIndex, (char *) &item, HASH_ENTER, foundPtr);
}
if (!result)
{
SpinRelease(BindingLock);
SpinRelease(ShmemIndexLock);
elog(ERROR, "ShmemInitStruct: Binding Table corrupted");
elog(ERROR, "ShmemInitStruct: Shmem Index corrupted");
return (NULL);
}
else if (*foundPtr)
{
/*
* Structure is in the binding table so someone else has allocated
* Structure is in the shmem index so someone else has allocated
* it already. The size better be the same as the size we are
* trying to initialize to or there is a name conflict (or worse).
*/
if (result->size != size)
{
SpinRelease(BindingLock);
SpinRelease(ShmemIndexLock);
elog(NOTICE, "ShmemInitStruct: BindingTable entry size is wrong");
elog(NOTICE, "ShmemInitStruct: ShmemIndex entry size is wrong");
/* let caller print its message too */
return (NULL);
}
@@ -558,9 +558,9 @@ ShmemInitStruct(char *name, unsigned long size, bool *foundPtr)
if (!structPtr)
{
/* out of memory */
Assert(BindingTable);
hash_search(BindingTable, (char *) &item, HASH_REMOVE, foundPtr);
SpinRelease(BindingLock);
Assert(ShmemIndex);
hash_search(ShmemIndex, (char *) &item, HASH_REMOVE, foundPtr);
SpinRelease(ShmemIndexLock);
*foundPtr = FALSE;
elog(NOTICE, "ShmemInitStruct: cannot allocate '%s'",
@@ -572,7 +572,7 @@ ShmemInitStruct(char *name, unsigned long size, bool *foundPtr)
}
Assert(ShmemIsValid((unsigned long) structPtr));
SpinRelease(BindingLock);
SpinRelease(ShmemIndexLock);
return (structPtr);
}
@@ -586,19 +586,19 @@ ShmemInitStruct(char *name, unsigned long size, bool *foundPtr)
bool
TransactionIdIsInProgress(TransactionId xid)
{
BindingEnt *result;
ShmemIndexEnt *result;
PROC *proc;
Assert(BindingTable);
Assert(ShmemIndex);
SpinAcquire(BindingLock);
SpinAcquire(ShmemIndexLock);
hash_seq((HTAB *) NULL);
while ((result = (BindingEnt *) hash_seq(BindingTable)) != NULL)
while ((result = (ShmemIndexEnt *) hash_seq(ShmemIndex)) != NULL)
{
if (result == (BindingEnt *) TRUE)
if (result == (ShmemIndexEnt *) TRUE)
{
SpinRelease(BindingLock);
SpinRelease(ShmemIndexLock);
return (false);
}
if (result->location == INVALID_OFFSET ||
@@ -607,12 +607,12 @@ TransactionIdIsInProgress(TransactionId xid)
proc = (PROC *) MAKE_PTR(result->location);
if (proc->xid == xid)
{
SpinRelease(BindingLock);
SpinRelease(ShmemIndexLock);
return (true);
}
}
SpinRelease(BindingLock);
elog(ERROR, "TransactionIdIsInProgress: BindingTable corrupted");
SpinRelease(ShmemIndexLock);
elog(ERROR, "TransactionIdIsInProgress: ShmemIndex corrupted");
return (false);
}

12
src/backend/storage/ipc/spin.c
View File

@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/Attic/spin.c,v 1.13 1998/06/23 16:04:46 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/Attic/spin.c,v 1.14 1998/06/27 15:47:45 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -53,7 +53,7 @@ bool
InitSpinLocks(int init, IPCKey key)
{
extern SPINLOCK ShmemLock;
extern SPINLOCK BindingLock;
extern SPINLOCK ShmemIndexLock;
extern SPINLOCK BufMgrLock;
extern SPINLOCK LockMgrLock;
extern SPINLOCK ProcStructLock;
@@ -66,7 +66,7 @@ InitSpinLocks(int init, IPCKey key)
/* These six spinlocks have fixed location is shmem */
ShmemLock = (SPINLOCK) SHMEMLOCKID;
BindingLock = (SPINLOCK) BINDINGLOCKID;
ShmemIndexLock = (SPINLOCK) SHMEMINDEXLOCKID;
BufMgrLock = (SPINLOCK) BUFMGRLOCKID;
LockMgrLock = (SPINLOCK) LOCKMGRLOCKID;
ProcStructLock = (SPINLOCK) PROCSTRUCTLOCKID;
@@ -265,7 +265,7 @@ AttachSpinLocks(IPCKey key)
* InitSpinLocks -- Spinlock bootstrapping
*
* We need several spinlocks for bootstrapping:
* BindingLock (for the shmem binding table) and
* ShmemIndexLock (for the shmem index table) and
* ShmemLock (for the shmem allocator), BufMgrLock (for buffer
* pool exclusive access), LockMgrLock (for the lock table), and
* ProcStructLock (a spin lock for the shared process structure).
@@ -277,7 +277,7 @@ bool
InitSpinLocks(int init, IPCKey key)
{
extern SPINLOCK ShmemLock;
extern SPINLOCK BindingLock;
extern SPINLOCK ShmemIndexLock;
extern SPINLOCK BufMgrLock;
extern SPINLOCK LockMgrLock;
extern SPINLOCK ProcStructLock;
@@ -305,7 +305,7 @@ InitSpinLocks(int init, IPCKey key)
/* These five (or six) spinlocks have fixed location is shmem */
ShmemLock = (SPINLOCK) SHMEMLOCKID;
BindingLock = (SPINLOCK) BINDINGLOCKID;
ShmemIndexLock = (SPINLOCK) SHMEMINDEXLOCKID;
BufMgrLock = (SPINLOCK) BUFMGRLOCKID;
LockMgrLock = (SPINLOCK) LOCKMGRLOCKID;
ProcStructLock = (SPINLOCK) PROCSTRUCTLOCKID;

8
src/backend/storage/lmgr/lock.c
View File

@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lock.c,v 1.29 1998/06/27 04:53:37 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lock.c,v 1.30 1998/06/27 15:47:46 momjian Exp $
*
* NOTES
* Outside modules can create a lock table and acquire/release
@@ -216,9 +216,9 @@ LockTypeInit(LOCKTAB *ltable,
* LockTableInit -- initialize a lock table structure
*
* Notes:
* (a) a lock table has four separate entries in the binding
* (a) a lock table has four separate entries in the shmem index
* table. This is because every shared hash table and spinlock
* has its name stored in the binding table at its creation. It
* has its name stored in the shmem index at its creation. It
* is wasteful, in this case, but not much space is involved.
*
*/
@@ -242,7 +242,7 @@ LockTableInit(char *tabName,
return (INVALID_TABLEID);
}
/* allocate a string for the binding table lookup */
/* allocate a string for the shmem index table lookup */
shmemName = (char *) palloc((unsigned) (strlen(tabName) + 32));
if (!shmemName)
{

8
src/backend/storage/lmgr/proc.c
View File

@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.37 1998/06/27 04:53:39 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.38 1998/06/27 15:47:46 momjian 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 1.37 1998/06/27 04:53:39 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.38 1998/06/27 15:47:46 momjian Exp $
*/
#include <sys/time.h>
#include <unistd.h>
@@ -184,7 +184,7 @@ InitProcess(IPCKey key)
{
/*
* have to allocate one. We can't use the normal binding table
* have to allocate one. We can't use the normal shmem index table
* mechanism because the proc structure is stored by PID instead
* of by a global name (need to look it up by PID when we cleanup
* dead processes).
@@ -261,7 +261,7 @@ InitProcess(IPCKey key)
MemSet(MyProc->sLocks, 0, MAX_SPINS * sizeof(*MyProc->sLocks));
/* -------------------------
* Install ourselves in the binding table. The name to
* Install ourselves in the shmem index table. The name to
* use is determined by the OS-assigned process id. That
* allows the cleanup process to find us after any untimely
* exit.