rxrpc: Add a tracepoint to track rxrpc_peer refcounting
Add a tracepoint to track reference counting on the rxrpc_peer struct.
Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/net/rxrpc/peer_object.c b/net/rxrpc/peer_object.c
index 94a6dbf..a4a750a 100644
--- a/net/rxrpc/peer_object.c
+++ b/net/rxrpc/peer_object.c
@@ -386,9 +386,54 @@ struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *local,
}
/*
- * Discard a ref on a remote peer record.
+ * Get a ref on a peer record.
*/
-void __rxrpc_put_peer(struct rxrpc_peer *peer)
+struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *peer)
+{
+ const void *here = __builtin_return_address(0);
+ int n;
+
+ n = atomic_inc_return(&peer->usage);
+ trace_rxrpc_peer(peer, rxrpc_peer_got, n, here);
+ return peer;
+}
+
+/*
+ * Get a ref on a peer record unless its usage has already reached 0.
+ */
+struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *peer)
+{
+ const void *here = __builtin_return_address(0);
+
+ if (peer) {
+ int n = __atomic_add_unless(&peer->usage, 1, 0);
+ if (n > 0)
+ trace_rxrpc_peer(peer, rxrpc_peer_got, n + 1, here);
+ else
+ peer = NULL;
+ }
+ return peer;
+}
+
+/*
+ * Queue a peer record. This passes the caller's ref to the workqueue.
+ */
+void __rxrpc_queue_peer_error(struct rxrpc_peer *peer)
+{
+ const void *here = __builtin_return_address(0);
+ int n;
+
+ n = atomic_read(&peer->usage);
+ if (rxrpc_queue_work(&peer->error_distributor))
+ trace_rxrpc_peer(peer, rxrpc_peer_queued_error, n, here);
+ else
+ rxrpc_put_peer(peer);
+}
+
+/*
+ * Discard a peer record.
+ */
+static void __rxrpc_put_peer(struct rxrpc_peer *peer)
{
struct rxrpc_net *rxnet = peer->local->rxnet;
@@ -402,6 +447,22 @@ void __rxrpc_put_peer(struct rxrpc_peer *peer)
kfree_rcu(peer, rcu);
}
+/*
+ * Drop a ref on a peer record.
+ */
+void rxrpc_put_peer(struct rxrpc_peer *peer)
+{
+ const void *here = __builtin_return_address(0);
+ int n;
+
+ if (peer) {
+ n = atomic_dec_return(&peer->usage);
+ trace_rxrpc_peer(peer, rxrpc_peer_put, n, here);
+ if (n == 0)
+ __rxrpc_put_peer(peer);
+ }
+}
+
/**
* rxrpc_kernel_get_peer - Get the peer address of a call
* @sock: The socket on which the call is in progress.