Remove ShutdownBufferPoolAccess exit callback, and do the work in

ProcKill instead, where we still have a PGPROC with which to wait on
LWLocks.  This fixes 'can't wait without a PROC structure' failures
occasionally seen during backend shutdown (I'm surprised they weren't
more frequent, actually).  Add an Assert() to LWLockAcquire to help
catch any similar mistakes in future.  Fix failure to update MyProcPid
for standalone backends and pgstat processes.

src/backend/storage/lmgr/lwlock.c

@@ -15,7 +15,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lwlock.c,v 1.13 2002/09/04 20:31:26 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lwlock.c,v 1.14 2002/09/25 20:31:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -203,6 +203,13 @@ LWLockAcquire(LWLockId lockid, LWLockMode mode)
 
 	PRINT_LWDEBUG("LWLockAcquire", lockid, lock);
 
+	/*
+	 * We can't wait if we haven't got a PGPROC.  This should only occur
+	 * during bootstrap or shared memory initialization.  Put an Assert
+	 * here to catch unsafe coding practices.
+	 */
+	Assert(!(proc == NULL && IsUnderPostmaster));
+
 	/*
 	 * Lock out cancel/die interrupts until we exit the code section
 	 * protected by the LWLock.  This ensures that interrupts will not