rxrpc: Fix conn expiry timers

Fix the rxrpc connection expiry timers so that connections for closed
AF_RXRPC sockets get deleted in a more timely fashion, freeing up the
transport UDP port much more quickly.

 (1) Replace the delayed work items with work items plus timers so that
     timer_reduce() can be used to shorten them and so that the timer
     doesn't requeue the work item if the net namespace is dead.

 (2) Don't use queue_delayed_work() as that won't alter the timeout if the
     timer is already running.

 (3) Don't rearm the timers if the network namespace is dead.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 19 insertions, 11 deletions

diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c
index 785dfdb9fef1..7f74ca3059f8 100644
--- a/net/rxrpc/conn_client.c
+++ b/net/rxrpc/conn_client.c
@@ -691,7 +691,7 @@ int rxrpc_connect_call(struct rxrpc_call *call,
 
 	_enter("{%d,%lx},", call->debug_id, call->user_call_ID);
 
-	rxrpc_discard_expired_client_conns(&rxnet->client_conn_reaper.work);
+	rxrpc_discard_expired_client_conns(&rxnet->client_conn_reaper);
 	rxrpc_cull_active_client_conns(rxnet);
 
 	ret = rxrpc_get_client_conn(call, cp, srx, gfp);
@@ -757,6 +757,18 @@ void rxrpc_expose_client_call(struct rxrpc_call *call)
 }
 
 /*
+ * Set the reap timer.
+ */
+static void rxrpc_set_client_reap_timer(struct rxrpc_net *rxnet)
+{
+	unsigned long now = jiffies;
+	unsigned long reap_at = now + rxrpc_conn_idle_client_expiry;
+
+	if (rxnet->live)
+		timer_reduce(&rxnet->client_conn_reap_timer, reap_at);
+}
+
+/*
  * Disconnect a client call.
  */
 void rxrpc_disconnect_client_call(struct rxrpc_call *call)
@@ -896,9 +908,7 @@ idle_connection:
 		list_move_tail(&conn->cache_link, &rxnet->idle_client_conns);
 		if (rxnet->idle_client_conns.next == &conn->cache_link &&
 		    !rxnet->kill_all_client_conns)
-			queue_delayed_work(rxrpc_workqueue,
-					   &rxnet->client_conn_reaper,
-					   rxrpc_conn_idle_client_expiry);
+			rxrpc_set_client_reap_timer(rxnet);
 	} else {
 		trace_rxrpc_client(conn, channel, rxrpc_client_to_inactive);
 		conn->cache_state = RXRPC_CONN_CLIENT_INACTIVE;
@@ -1036,8 +1046,7 @@ void rxrpc_discard_expired_client_conns(struct work_struct *work)
 {
 	struct rxrpc_connection *conn;
 	struct rxrpc_net *rxnet =
-		container_of(to_delayed_work(work),
-			     struct rxrpc_net, client_conn_reaper);
+		container_of(work, struct rxrpc_net, client_conn_reaper);
 	unsigned long expiry, conn_expires_at, now;
 	unsigned int nr_conns;
 	bool did_discard = false;
@@ -1116,9 +1125,8 @@ not_yet_expired:
 	 */
 	_debug("not yet");
 	if (!rxnet->kill_all_client_conns)
-		queue_delayed_work(rxrpc_workqueue,
-				   &rxnet->client_conn_reaper,
-				   conn_expires_at - now);
+		timer_reduce(&rxnet->client_conn_reap_timer,
+			     conn_expires_at);
 
 out:
 	spin_unlock(&rxnet->client_conn_cache_lock);
@@ -1138,9 +1146,9 @@ void rxrpc_destroy_all_client_connections(struct rxrpc_net *rxnet)
 	rxnet->kill_all_client_conns = true;
 	spin_unlock(&rxnet->client_conn_cache_lock);
 
-	cancel_delayed_work(&rxnet->client_conn_reaper);
+	del_timer_sync(&rxnet->client_conn_reap_timer);
 
-	if (!queue_delayed_work(rxrpc_workqueue, &rxnet->client_conn_reaper, 0))
+	if (!rxrpc_queue_work(&rxnet->client_conn_reaper))
 		_debug("destroy: queue failed");
 
 	_leave("");