summaryrefslogtreecommitdiff
path: root/net/rxrpc/local_object.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/rxrpc/local_object.c')
-rw-r--r--net/rxrpc/local_object.c103
1 files changed, 64 insertions, 39 deletions
diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
index b1c71bad510b..72a6e12a9304 100644
--- a/net/rxrpc/local_object.c
+++ b/net/rxrpc/local_object.c
@@ -79,6 +79,7 @@ static struct rxrpc_local *rxrpc_alloc_local(struct rxrpc_net *rxnet,
local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
if (local) {
atomic_set(&local->usage, 1);
+ atomic_set(&local->active_users, 1);
local->rxnet = rxnet;
INIT_LIST_HEAD(&local->link);
INIT_WORK(&local->processor, rxrpc_local_processor);
@@ -92,7 +93,7 @@ static struct rxrpc_local *rxrpc_alloc_local(struct rxrpc_net *rxnet,
local->debug_id = atomic_inc_return(&rxrpc_debug_id);
memcpy(&local->srx, srx, sizeof(*srx));
local->srx.srx_service = 0;
- trace_rxrpc_local(local, rxrpc_local_new, 1, NULL);
+ trace_rxrpc_local(local->debug_id, rxrpc_local_new, 1, NULL);
}
_leave(" = %p", local);
@@ -266,11 +267,8 @@ struct rxrpc_local *rxrpc_lookup_local(struct net *net,
* bind the transport socket may still fail if we're attempting
* to use a local address that the dying object is still using.
*/
- if (!rxrpc_get_local_maybe(local)) {
- cursor = cursor->next;
- list_del_init(&local->link);
+ if (!rxrpc_use_local(local))
break;
- }
age = "old";
goto found;
@@ -284,7 +282,10 @@ struct rxrpc_local *rxrpc_lookup_local(struct net *net,
if (ret < 0)
goto sock_error;
- list_add_tail(&local->link, cursor);
+ if (cursor != &rxnet->local_endpoints)
+ list_replace_init(cursor, &local->link);
+ else
+ list_add_tail(&local->link, cursor);
age = "new";
found:
@@ -320,7 +321,7 @@ struct rxrpc_local *rxrpc_get_local(struct rxrpc_local *local)
int n;
n = atomic_inc_return(&local->usage);
- trace_rxrpc_local(local, rxrpc_local_got, n, here);
+ trace_rxrpc_local(local->debug_id, rxrpc_local_got, n, here);
return local;
}
@@ -334,7 +335,8 @@ struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *local)
if (local) {
int n = atomic_fetch_add_unless(&local->usage, 1, 0);
if (n > 0)
- trace_rxrpc_local(local, rxrpc_local_got, n + 1, here);
+ trace_rxrpc_local(local->debug_id, rxrpc_local_got,
+ n + 1, here);
else
local = NULL;
}
@@ -342,24 +344,18 @@ struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *local)
}
/*
- * Queue a local endpoint.
+ * Queue a local endpoint and pass the caller's reference to the work item.
*/
void rxrpc_queue_local(struct rxrpc_local *local)
{
const void *here = __builtin_return_address(0);
+ unsigned int debug_id = local->debug_id;
+ int n = atomic_read(&local->usage);
if (rxrpc_queue_work(&local->processor))
- trace_rxrpc_local(local, rxrpc_local_queued,
- atomic_read(&local->usage), here);
-}
-
-/*
- * A local endpoint reached its end of life.
- */
-static void __rxrpc_put_local(struct rxrpc_local *local)
-{
- _enter("%d", local->debug_id);
- rxrpc_queue_work(&local->processor);
+ trace_rxrpc_local(debug_id, rxrpc_local_queued, n, here);
+ else
+ rxrpc_put_local(local);
}
/*
@@ -372,10 +368,47 @@ void rxrpc_put_local(struct rxrpc_local *local)
if (local) {
n = atomic_dec_return(&local->usage);
- trace_rxrpc_local(local, rxrpc_local_put, n, here);
+ trace_rxrpc_local(local->debug_id, rxrpc_local_put, n, here);
if (n == 0)
- __rxrpc_put_local(local);
+ call_rcu(&local->rcu, rxrpc_local_rcu);
+ }
+}
+
+/*
+ * Start using a local endpoint.
+ */
+struct rxrpc_local *rxrpc_use_local(struct rxrpc_local *local)
+{
+ unsigned int au;
+
+ local = rxrpc_get_local_maybe(local);
+ if (!local)
+ return NULL;
+
+ au = atomic_fetch_add_unless(&local->active_users, 1, 0);
+ if (au == 0) {
+ rxrpc_put_local(local);
+ return NULL;
+ }
+
+ return local;
+}
+
+/*
+ * Cease using a local endpoint. Once the number of active users reaches 0, we
+ * start the closure of the transport in the work processor.
+ */
+void rxrpc_unuse_local(struct rxrpc_local *local)
+{
+ unsigned int au;
+
+ if (local) {
+ au = atomic_dec_return(&local->active_users);
+ if (au == 0)
+ rxrpc_queue_local(local);
+ else
+ rxrpc_put_local(local);
}
}
@@ -393,16 +426,6 @@ static void rxrpc_local_destroyer(struct rxrpc_local *local)
_enter("%d", local->debug_id);
- /* We can get a race between an incoming call packet queueing the
- * processor again and the work processor starting the destruction
- * process which will shut down the UDP socket.
- */
- if (local->dead) {
- _leave(" [already dead]");
- return;
- }
- local->dead = true;
-
mutex_lock(&rxnet->local_mutex);
list_del_init(&local->link);
mutex_unlock(&rxnet->local_mutex);
@@ -422,13 +445,11 @@ static void rxrpc_local_destroyer(struct rxrpc_local *local)
*/
rxrpc_purge_queue(&local->reject_queue);
rxrpc_purge_queue(&local->event_queue);
-
- _debug("rcu local %d", local->debug_id);
- call_rcu(&local->rcu, rxrpc_local_rcu);
}
/*
- * Process events on an endpoint
+ * Process events on an endpoint. The work item carries a ref which
+ * we must release.
*/
static void rxrpc_local_processor(struct work_struct *work)
{
@@ -436,13 +457,15 @@ static void rxrpc_local_processor(struct work_struct *work)
container_of(work, struct rxrpc_local, processor);
bool again;
- trace_rxrpc_local(local, rxrpc_local_processing,
+ trace_rxrpc_local(local->debug_id, rxrpc_local_processing,
atomic_read(&local->usage), NULL);
do {
again = false;
- if (atomic_read(&local->usage) == 0)
- return rxrpc_local_destroyer(local);
+ if (atomic_read(&local->active_users) == 0) {
+ rxrpc_local_destroyer(local);
+ break;
+ }
if (!skb_queue_empty(&local->reject_queue)) {
rxrpc_reject_packets(local);
@@ -454,6 +477,8 @@ static void rxrpc_local_processor(struct work_struct *work)
again = true;
}
} while (again);
+
+ rxrpc_put_local(local);
}
/*