From 26aa8b09dbc2de1c7bdd97921a273511d585e043 Mon Sep 17 00:00:00 2001
From: Rainer Gerhards <rgerhards@adiscon.com>
Date: Mon, 31 Mar 2008 09:07:24 +0000
Subject: worked a bit on atomic memory operations to support problem-free
 threading     (only at non-intrusive places)

---
 ChangeLog |  4 ++++
 atomic.h  |  8 +++++++-
 debug.c   |  2 ++
 modules.c |  2 +-
 msg.c     | 19 +++++++++++++++----
 5 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index bfe7f406..d51ff510 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,10 @@ Version 3.12.6 (rgerhards), 2008-04-??
   supports multiple opens of the same module without any memory footprint.
 - removed --enable-mudflap, added --enable-valgrind ./configure setting
 - bugfix: tcp receiver could segfault due to uninitialized variable
+- docfix: queue doc had a wrong directive name that prevented max worker
+  threads to be correctly set
+- worked a bit on atomic memory operations to support problem-free
+  threading (only at non-intrusive places)
 ---------------------------------------------------------------------------
 Version 3.12.5 (rgerhards), 2008-03-28
 - changed default for "last message repeated n times", which is now
diff --git a/atomic.h b/atomic.h
index 28ed24e5..1883e030 100644
--- a/atomic.h
+++ b/atomic.h
@@ -6,6 +6,9 @@
  * because in the non-presence of them, we simply do it without atomicitiy.
  * Which, for word-aligned data types, usually (but only usually!) should work.
  *
+ * We are using the functions described in
+ * http:/gcc.gnu.org/onlinedocs/gcc/Atomic-Builtins.html
+ *
  * THESE MACROS MUST ONLY BE USED WITH WORD-SIZED DATA TYPES!
  *
  * Copyright 2008 Rainer Gerhards and Adiscon GmbH.
@@ -32,6 +35,9 @@
 #ifndef INCLUDED_ATOMIC_H
 #define INCLUDED_ATOMIC_H
 
-#define ATOMIC_INC(data) __sync_fetch_and_add(&data, 1);
+/* set the following to 1 if we have atomic operations (and #undef it otherwise) */
+#define DO_HAVE_ATOMICS 1
+#define ATOMIC_INC(data) ((void) __sync_fetch_and_add(&data, 1))
+#define ATOMIC_DEC_AND_FETCH(data) __sync_sub_and_fetch(&data, 1)
 
 #endif /* #ifndef INCLUDED_ATOMIC_H */
diff --git a/debug.c b/debug.c
index 350bb6fb..29c65cf1 100644
--- a/debug.c
+++ b/debug.c
@@ -660,7 +660,9 @@ static void dbgCallStackDestruct(void *arg)
 		free(pThrd->pszThrdName);
 	}
 
+ 	pthread_mutex_lock(&mutCallStack);
 	DLL_Del(CallStack, pThrd);
+ 	pthread_mutex_unlock(&mutCallStack);
 }
 
 
diff --git a/modules.c b/modules.c
index ad78e6e8..b6164f91 100644
--- a/modules.c
+++ b/modules.c
@@ -87,7 +87,7 @@ modUsrAdd(modInfo_t *pThis, char *pszUsr)
 	pThis->pModUsrRoot = pUsr;
 
 finalize_it:
-	ENDfunc
+	ENDfunc;
 }
 
 
diff --git a/msg.c b/msg.c
index 0dd8f416..76ea2f72 100644
--- a/msg.c
+++ b/msg.c
@@ -43,6 +43,7 @@
 #include "var.h"
 #include "datetime.h"
 #include "regexp.h"
+#include "atomic.h"
 
 /* static data */
 DEFobjStaticHelpers
@@ -241,9 +242,15 @@ finalize_it:
 
 
 BEGINobjDestruct(msg) /* be sure to specify the object type also in END and CODESTART macros! */
+	int currRefCount;
 CODESTARTobjDestruct(msg)
 	/* DEV Debugging only ! dbgprintf("msgDestruct\t0x%lx, Ref now: %d\n", (unsigned long)pM, pM->iRefCount - 1); */
-	if(--pThis->iRefCount == 0)
+#	ifdef DO_HAVE_ATOMICS
+		currRefCount = ATOMIC_DEC_AND_FETCH(pThis->iRefCount);
+#	else
+		currRefCount = --pThis->iRefCount;
+# 	endif
+	if(currRefCount == 0)
 	{
 		/* DEV Debugging Only! dbgprintf("msgDestruct\t0x%lx, RefCount now 0, doing DESTROY\n", (unsigned long)pThis); */
 		if(pThis->pszUxTradMsg != NULL)
@@ -438,9 +445,13 @@ finalize_it:
 msg_t *MsgAddRef(msg_t *pM)
 {
 	assert(pM != NULL);
-	MsgLock(pM);
-	pM->iRefCount++;
-	MsgUnlock(pM);
+#	ifdef DO_HAVE_ATOMICS
+		ATOMIC_INC(pM->iRefCount);
+#	else
+		MsgLock(pM);
+		pM->iRefCount++;
+		MsgUnlock(pM);
+#	endif
 	/* DEV debugging only! dbgprintf("MsgAddRef\t0x%x done, Ref now: %d\n", (int)pM, pM->iRefCount);*/
 	return(pM);
 }
-- 
cgit