From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Mon, 30 Sep 2002 20:18:59 +0000 (+0000)
Subject: Back-patch fix for 'can't wait without a PROC structure' failures:
X-Git-Tag: REL7_2_3~5
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=c9e3806e57589570a746e875a69a95fe5149ba53;p=postgresql

Back-patch fix for 'can't wait without a PROC structure' failures:
remove separate ShutdownBufferPoolAccess exit callback, and do the
work in ProcKill instead, before we delete MyProc.
---

diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index f3b6f1f955..420f19499b 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootstrap.c,v 1.120.2.2 2002/09/30 19:55:08 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootstrap.c,v 1.120.2.3 2002/09/30 20:18:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -359,6 +359,9 @@ BootstrapMain(int argc, char *argv[])
 
 	BaseInit();
 
+	if (IsUnderPostmaster)
+		InitDummyProcess();		/* needed to get LWLocks */
+
 	/*
 	 * XLOG operations
 	 */
@@ -376,8 +379,6 @@ BootstrapMain(int argc, char *argv[])
 			break;
 
 		case BS_XLOG_CHECKPOINT:
-			if (IsUnderPostmaster)
-				InitDummyProcess();		/* needed to get LWLocks */
 			CreateDummyCaches();
 			CreateCheckPoint(false, false);
 			SetSavedRedoRecPtr(); /* pass redo ptr back to postmaster */
diff --git a/src/backend/storage/buffer/buf_init.c b/src/backend/storage/buffer/buf_init.c
index 37570e6b11..eca2548ab5 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 1.47 2001/11/05 17:46:27 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.47.2.1 2002/09/30 20:18:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -36,8 +36,6 @@
 #include "utils/memutils.h"
 
 
-static void ShutdownBufferPoolAccess(void);
-
 /*
  *	if BMTRACE is defined, we trace the last 200 buffer allocations and
  *	deallocations in a circular buffer in shared memory.
@@ -244,27 +242,6 @@ InitBufferPoolAccess(void)
 	 */
 	for (i = 0; i < NBuffers; i++)
 		BufferBlockPointers[i] = (Block) MAKE_PTR(BufferDescriptors[i].data);
-
-	/*
-	 * Now that buffer access is initialized, set up a callback to shut it
-	 * down again at backend exit.
-	 */
-	on_shmem_exit(ShutdownBufferPoolAccess, 0);
-}
-
-/*
- * Shut down buffer manager at backend exit.
- *
- * This is needed mainly to ensure that we don't leave any buffer reference
- * counts set during an error exit.
- */
-static void
-ShutdownBufferPoolAccess(void)
-{
-	/* Release any buffer context locks we are holding */
-	UnlockBuffers();
-	/* Release any buffer reference counts we are holding */
-	ResetBufferPool(false);
 }
 
 /* -----------------------------------------------------
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index 4f82016c59..c3e361c1d1 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/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 1.8 2002/01/07 16:33:00 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lwlock.c,v 1.8.2.1 2002/09/30 20:18:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -204,6 +204,13 @@ LWLockAcquire(LWLockId lockid, LWLockMode mode)
 
 	PRINT_LWDEBUG("LWLockAcquire", lockid, lock);
 
+	/*
+	 * We can't wait if we haven't got a PROC.  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
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index b1be68a881..7fcd7325f9 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.117 2001/12/28 18:16:43 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/lmgr/proc.c,v 1.117.2.1 2002/09/30 20:18:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -449,6 +449,10 @@ ProcKill(void)
 
 	/* Abort any buffer I/O in progress */
 	AbortBufferIO();
+	/* Release any buffer context locks we are holding */
+	UnlockBuffers();
+	/* Release any buffer reference counts we are holding */
+	ResetBufferPool(false);
 
 	/* Get off any wait queue I might be on */
 	LockWaitCancel();
@@ -492,6 +496,10 @@ DummyProcKill(void)
 
 	/* Abort any buffer I/O in progress */
 	AbortBufferIO();
+	/* Release any buffer context locks we are holding */
+	UnlockBuffers();
+	/* Release any buffer reference counts we are holding */
+	ResetBufferPool(false);
 
 	/* I can't be on regular lock queues, so needn't check */