Significant cleanups in SysV IPC handling (shared mem and semaphores).

IPC key assignment will now work correctly even when multiple postmasters
are using same logical port number (which is possible given -k switch).
There is only one shared-mem segment per postmaster now, not 3.
Rip out broken code for non-TAS case in bufmgr and xlog, substitute a
complete S_LOCK emulation using semaphores in spin.c.  TAS and non-TAS
logic is now exactly the same.
When deadlock is detected, "Deadlock detected" is now the elog(ERROR)
message, rather than a NOTICE that comes out before an unhelpful ERROR.

1 files changed, 3 insertions, 40 deletions

diff --git a/src/backend/storage/buffer/buf_init.c b/src/backend/storage/buffer/buf_init.c
index 3c40009422d..0fda21972f6 100644
--- a/src/backend/storage/buffer/buf_init.c
+++ b/src/backend/storage/buffer/buf_init.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.37 2000/10/23 04:10:06 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.38 2000/11/28 23:27:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -56,13 +56,6 @@ int			Num_Descriptors;
 BufferDesc *BufferDescriptors;
 BufferBlock BufferBlocks;
 
-#ifndef HAS_TEST_AND_SET
-long	   *NWaitIOBackendP;
-
-#endif
-
-extern IpcSemaphoreId WaitIOSemId;
-
 long	   *PrivateRefCount;	/* also used in freelist.c */
 bits8	   *BufferLocks;		/* flag bits showing locks I have set */
 BufferTag  *BufferTagLastDirtied;		/* tag buffer had when last
@@ -139,7 +132,7 @@ long int	LocalBufferFlushCount;
  * amount of available memory.
  */
 void
-InitBufferPool(IPCKey key)
+InitBufferPool(void)
 {
 	bool		foundBufs,
 				foundDescs;
@@ -170,18 +163,6 @@ InitBufferPool(IPCKey key)
 		ShmemInitStruct("Buffer Blocks",
 						NBuffers * BLCKSZ, &foundBufs);
 
-#ifndef HAS_TEST_AND_SET
-	{
-		bool		foundNWaitIO;
-
-		NWaitIOBackendP = (long *) ShmemInitStruct("#Backends Waiting IO",
-												   sizeof(long),
-												   &foundNWaitIO);
-		if (!foundNWaitIO)
-			*NWaitIOBackendP = 0;
-	}
-#endif
-
 	if (foundDescs || foundBufs)
 	{
 
@@ -214,10 +195,8 @@ InitBufferPool(IPCKey key)
 			buf->flags = (BM_DELETED | BM_FREE | BM_VALID);
 			buf->refcount = 0;
 			buf->buf_id = i;
-#ifdef HAS_TEST_AND_SET
 			S_INIT_LOCK(&(buf->io_in_progress_lock));
 			S_INIT_LOCK(&(buf->cntx_lock));
-#endif
 		}
 
 		/* close the circular queue */
@@ -231,22 +210,6 @@ InitBufferPool(IPCKey key)
 
 	SpinRelease(BufMgrLock);
 
-#ifndef HAS_TEST_AND_SET
-	{
-		extern IpcSemaphoreId WaitIOSemId;
-		extern IpcSemaphoreId WaitCLSemId;
-
-		WaitIOSemId = IpcSemaphoreCreate(IPCKeyGetWaitIOSemaphoreKey(key),
-										 1, IPCProtection, 0, 1);
-		if (WaitIOSemId < 0)
-			elog(FATAL, "InitBufferPool: IpcSemaphoreCreate(WaitIOSemId) failed");
-		WaitCLSemId = IpcSemaphoreCreate(IPCKeyGetWaitCLSemaphoreKey(key),
-										 1, IPCProtection,
-									   IpcSemaphoreDefaultStartValue, 1);
-		if (WaitCLSemId < 0)
-			elog(FATAL, "InitBufferPool: IpcSemaphoreCreate(WaitCLSemId) failed");
-	}
-#endif
 	PrivateRefCount = (long *) calloc(NBuffers, sizeof(long));
 	BufferLocks = (bits8 *) calloc(NBuffers, sizeof(bits8));
 	BufferTagLastDirtied = (BufferTag *) calloc(NBuffers, sizeof(BufferTag));
@@ -262,7 +225,7 @@ InitBufferPool(IPCKey key)
  * ----------------------------------------------------
  */
 int
-BufferShmemSize()
+BufferShmemSize(void)
 {
 	int			size = 0;