X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=urcu-call-rcu-impl.h;h=9beb58cbf59cfba7d8f82aae5e85fb8882db9e70;hb=bf33aaea06cbf8257cc49c38abca6d26c0c31c78;hp=69edd49f422dfdbe36524b64f7037ca66cec34fa;hpb=263e3cf98bd9b7e6b352e25b8007bd1b6df250b8;p=urcu.git

diff --git a/urcu-call-rcu-impl.h b/urcu-call-rcu-impl.h
index 69edd49..9beb58c 100644
--- a/urcu-call-rcu-impl.h
+++ b/urcu-call-rcu-impl.h
@@ -48,7 +48,7 @@ struct call_rcu_data {
 	unsigned long flags;
 	pthread_mutex_t mtx;
 	int futex;
-	unsigned long qlen;
+	unsigned long qlen; /* maintained for debugging. */
 	pthread_t tid;
 	int cpu_affinity;
 	struct cds_list_head list;
@@ -212,6 +212,11 @@ static void *call_rcu_thread(void *arg)
 
 	thread_call_rcu_data = crdp;
 	for (;;) {
+		if (!(crdp->flags & URCU_CALL_RCU_RT)) {
+			uatomic_dec(&crdp->futex);
+			/* Decrement futex before reading call_rcu list */
+			cmm_smp_mb();
+		}
 		if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
 			while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
 				poll(NULL, 0, 1);
@@ -235,15 +240,21 @@ static void *call_rcu_thread(void *arg)
 			} while (cbs != NULL);
 			uatomic_sub(&crdp->qlen, cbcount);
 		}
-		if (crdp->flags & URCU_CALL_RCU_STOP)
+		if (crdp->flags & URCU_CALL_RCU_STOP) {
+			if (!(crdp->flags & URCU_CALL_RCU_RT)) {
+				/*
+				 * Read call_rcu list before write futex.
+				 */
+				cmm_smp_mb();
+				uatomic_set(&crdp->futex, 0);
+			}
 			break;
-		if (crdp->flags & URCU_CALL_RCU_RT)
-			poll(NULL, 0, 10);
-		else {
+		}
+		if (!(crdp->flags & URCU_CALL_RCU_RT)) {
 			if (&crdp->cbs.head == _CMM_LOAD_SHARED(crdp->cbs.tail))
 				call_rcu_wait(crdp);
-			poll(NULL, 0, 10);
 		}
+		poll(NULL, 0, 10);
 	}
 	call_rcu_lock(&crdp->mtx);
 	crdp->flags |= URCU_CALL_RCU_STOPPED;