X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=urcu-call-rcu-impl.h;h=0a47d969a4e8d3f50438fc69bbede379e6715c50;hb=60af049d5e1d17e7ffdfd139bb486bd969c6a76c;hp=c822646e03834bbf26224feae2a71bcdfb5bf8e1;hpb=3670fef2faef63803d62a08f2aa4f089f3858b50;p=userspace-rcu.git

diff --git a/urcu-call-rcu-impl.h b/urcu-call-rcu-impl.h
index c822646..0a47d96 100644
--- a/urcu-call-rcu-impl.h
+++ b/urcu-call-rcu-impl.h
@@ -88,6 +88,11 @@ static struct call_rcu_data *default_call_rcu_data;
 static struct call_rcu_data **per_cpu_call_rcu_data;
 static long maxcpus;
 
+static void maxcpus_reset(void)
+{
+	maxcpus = 0;
+}
+
 /* Allocate the array if it has not already been allocated. */
 
 static void alloc_cpu_call_rcu_data(void)
@@ -123,6 +128,10 @@ static void alloc_cpu_call_rcu_data(void)
 static struct call_rcu_data **per_cpu_call_rcu_data = NULL;
 static const long maxcpus = -1;
 
+static void maxcpus_reset(void)
+{
+}
+
 static void alloc_cpu_call_rcu_data(void)
 {
 }
@@ -396,11 +405,19 @@ int set_cpu_call_rcu_data(int cpu, struct call_rcu_data *crdp)
 		errno = EINVAL;
 		return -EINVAL;
 	}
+
 	if (per_cpu_call_rcu_data == NULL) {
 		call_rcu_unlock(&call_rcu_mutex);
 		errno = ENOMEM;
 		return -ENOMEM;
 	}
+
+	if (per_cpu_call_rcu_data[cpu] != NULL && crdp != NULL) {
+		call_rcu_unlock(&call_rcu_mutex);
+		errno = EEXIST;
+		return -EEXIST;
+	}
+
 	per_cpu_call_rcu_data[cpu] = crdp;
 	call_rcu_unlock(&call_rcu_mutex);
 	return 0;
@@ -514,8 +531,13 @@ int create_all_cpu_call_rcu_data(unsigned long flags)
 		}
 		call_rcu_unlock(&call_rcu_mutex);
 		if ((ret = set_cpu_call_rcu_data(i, crdp)) != 0) {
-			/* FIXME: Leaks crdp for now. */
-			return ret; /* Can happen on race. */
+			call_rcu_data_free(crdp);
+
+			/* it has been created by other thread */
+			if (ret == -EEXIST)
+				continue;
+
+			return ret;
 		}
 	}
 	return 0;
@@ -596,6 +618,8 @@ void call_rcu_data_free(struct call_rcu_data *crdp)
 		_CMM_STORE_SHARED(crdp->cbs.head, NULL);
 		cbs_tail = (struct cds_wfq_node **)
 			uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
+		/* Create default call rcu data if need be */
+		(void) get_default_call_rcu_data();
 		cbs_endprev = (struct cds_wfq_node **)
 			uatomic_xchg(&default_call_rcu_data, cbs_tail);
 		*cbs_endprev = cbs;
@@ -604,7 +628,10 @@ void call_rcu_data_free(struct call_rcu_data *crdp)
 		wake_call_rcu_thread(default_call_rcu_data);
 	}
 
+	call_rcu_lock(&call_rcu_mutex);
 	cds_list_del(&crdp->list);
+	call_rcu_unlock(&call_rcu_mutex);
+
 	free(crdp);
 }
 
@@ -659,6 +686,10 @@ void call_rcu_after_fork_child(void)
 	/* Release the mutex. */
 	call_rcu_unlock(&call_rcu_mutex);
 
+	/* Do nothing when call_rcu() has not been used */
+	if (cds_list_empty(&call_rcu_data_list))
+		return;
+
 	/*
 	 * Allocate a new default call_rcu_data structure in order
 	 * to get a working call_rcu thread to go with it.
@@ -666,6 +697,12 @@ void call_rcu_after_fork_child(void)
 	default_call_rcu_data = NULL;
 	(void)get_default_call_rcu_data();
 
+	/* Cleanup call_rcu_data pointers before use */
+	maxcpus_reset();
+	free(per_cpu_call_rcu_data);
+	per_cpu_call_rcu_data = NULL;
+	thread_call_rcu_data = NULL;
+
 	/* Dispose of all of the rest of the call_rcu_data structures. */
 	cds_list_for_each_entry_safe(crdp, next, &call_rcu_data_list, list) {
 		if (crdp == default_call_rcu_data)