From 92c2e09d19bef9dd10d2e85a663925124d6e00e4 Mon Sep 17 00:00:00 2001
From: Rainer Gerhards <rgerhards@adiscon.com>
Date: Fri, 26 Sep 2008 18:40:28 +0200
Subject: some more threading cleanup

- removed newly-introduced potential deadlock in debug system
- removed unnecessary pthread_cond_signal
- a bit general cleanup
---
 runtime/debug.c | 15 +++++++++++++--
 runtime/queue.c |  8 ++------
 2 files changed, 15 insertions(+), 8 deletions(-)

(limited to 'runtime')

diff --git a/runtime/debug.c b/runtime/debug.c
index 15e9201b..b0bf76ea 100644
--- a/runtime/debug.c
+++ b/runtime/debug.c
@@ -772,6 +772,17 @@ dbgprint(obj_t *pObj, char *pszMsg, size_t lenMsg)
 	char pszWriteBuf[1024];
 	size_t lenWriteBuf;
 	struct timespec t;
+	uchar *pszObjName = NULL;
+
+	/* we must get the object name before we lock the mutex, because the object
+	 * potentially calls back into us. If we locked the mutex, we would deadlock
+	 * ourselfs. On the other hand, the GetName call needs not to be protected, as
+	 * this thread has a valid reference. If such an object is deleted by another
+	 * thread, we are in much more trouble than just for dbgprint(). -- rgerhards, 2008-09-26
+	 */
+	if(pObj != NULL) {
+		pszObjName = obj.GetName(pObj);
+	}
 
 	pthread_mutex_lock(&mutdbgprint);
 	pthread_cleanup_push(dbgMutexCancelCleanupHdlr, &mutdbgprint);
@@ -810,8 +821,8 @@ dbgprint(obj_t *pObj, char *pszMsg, size_t lenMsg)
 		if(stddbg != -1) write(stddbg, pszWriteBuf, lenWriteBuf);
 		if(altdbg != -1) write(altdbg, pszWriteBuf, lenWriteBuf);
 		/* print object name header if we have an object */
-		if(pObj != NULL) {
-			lenWriteBuf = snprintf(pszWriteBuf, sizeof(pszWriteBuf), "%s: ", obj.GetName(pObj));
+		if(pszObjName != NULL) {
+			lenWriteBuf = snprintf(pszWriteBuf, sizeof(pszWriteBuf), "%s: ", pszObjName);
 			if(stddbg != -1) write(stddbg, pszWriteBuf, lenWriteBuf);
 			if(altdbg != -1) write(altdbg, pszWriteBuf, lenWriteBuf);
 		}
diff --git a/runtime/queue.c b/runtime/queue.c
index c0a37019..3fae4aa7 100644
--- a/runtime/queue.c
+++ b/runtime/queue.c
@@ -2092,7 +2092,6 @@ queueEnqObj(queue_t *pThis, flowControl_t flowCtlType, void *pUsr)
 {
 	DEFiRet;
 	int iCancelStateSave;
-	int i;
 	struct timespec t;
 
 	ISOBJ_TYPE_assert(pThis, queue);
@@ -2172,13 +2171,10 @@ queueEnqObj(queue_t *pThis, flowControl_t flowCtlType, void *pUsr)
 finalize_it:
 	if(pThis->qType != QUEUETYPE_DIRECT) {
 		/* make sure at least one worker is running. */
-		if(pThis->qType != QUEUETYPE_DIRECT) {
-			queueAdviseMaxWorkers(pThis);
-		}
+		queueAdviseMaxWorkers(pThis);
+		dbgoprint((obj_t*) pThis, "EnqueueMsg advised worker start\n");
 		/* and release the mutex */
-		i = pthread_cond_signal(&pThis->notEmpty);
 		d_pthread_mutex_unlock(pThis->mut);
-		dbgoprint((obj_t*) pThis, "EnqueueMsg signaled condition (%d)\n", i);
 		pthread_setcancelstate(iCancelStateSave, NULL);
 	}
 
-- 
cgit