bugfix: problems with atomic operations emulation

replaced atomic operation emulation with new code. The previous code
seemed to have some issue and also limited concurrency severely. The
whole atomic operation emulation has been rewritten.

1 files changed, 17 insertions, 1 deletions

diff --git a/runtime/wtp.c b/runtime/wtp.c
index 271c6f0d..fff37c2f 100644
--- a/runtime/wtp.c
+++ b/runtime/wtp.c
@@ -97,6 +97,7 @@ BEGINobjConstruct(wtp) /* be sure to specify the object type also in END macro!
 	pThis->pfOnWorkerCancel = NotImplementedDummy;
 	pThis->pfOnWorkerStartup = NotImplementedDummy;
 	pThis->pfOnWorkerShutdown = NotImplementedDummy;
+	INIT_ATOMIC_HELPER_MUT(pThis->mutThrdStateChanged);
 ENDobjConstruct(wtp)
 
 
@@ -153,6 +154,7 @@ CODESTARTobjDestruct(wtp)
 	pthread_cond_destroy(&pThis->condThrdTrm);
 	pthread_mutex_destroy(&pThis->mut);
 	pthread_mutex_destroy(&pThis->mutThrdShutdwn);
+	DESTROY_ATOMIC_HELPER_MUT(pThis->mutThrdStateChanged);
 
 	free(pThis->pszDbgHdr);
 ENDobjDestruct(wtp)
@@ -186,6 +188,20 @@ wtpWakeupAllWrkr(wtp_t *pThis)
 }
 
 
+/* set the bThrdStateChanged in an atomic way. Note that
+ * val may only be 0 or 1.
+ */
+void
+wtpSetThrdStateChanged(wtp_t *pThis, int val)
+{
+	if(val == 0) {
+		ATOMIC_STORE_0_TO_INT(&pThis->bThrdStateChanged, pThis->mutThrdStateChanged);
+	} else {
+		ATOMIC_STORE_1_TO_INT(&pThis->bThrdStateChanged, pThis->mutThrdStateChanged);
+	}
+}
+
+
 /* check if we had any worker thread changes and, if so, act
  * on them. At a minimum, terminated threads are harvested (joined).
  * This function MUST NEVER block on the queue mutex!
@@ -216,7 +232,7 @@ wtpProcessThrdChanges(wtp_t *pThis)
 	 */
 	do {
 		/* reset the change marker */
-		ATOMIC_STORE_0_TO_INT(pThis->bThrdStateChanged);
+		wtpSetThrdStateChanged(pThis, 0);
 		/* go through all threads */
 		for(i = 0 ; i < pThis->iNumWorkerThreads ; ++i) {
 			wtiProcessThrdChanges(pThis->pWrkr[i], LOCK_MUTEX);