Commit 1159d4b4 authored by David Howells's avatar David Howells
Browse files

rxrpc: Add a tracepoint to track rxrpc_peer refcounting 



Add a tracepoint to track reference counting on the rxrpc_peer struct.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
parent 31f5f9a1

include/trace/events/rxrpc.h

+42 −0
Original line number Diff line number Diff line
@@ -50,6 +50,14 @@ enum rxrpc_local_trace { 
	rxrpc_local_queued,

};



enum rxrpc_peer_trace {

	rxrpc_peer_got,

	rxrpc_peer_new,

	rxrpc_peer_processing,

	rxrpc_peer_put,

	rxrpc_peer_queued_error,

};



enum rxrpc_conn_trace {

	rxrpc_conn_got,

	rxrpc_conn_new_client,
@@ -230,6 +238,13 @@ enum rxrpc_congest_change { 
	EM(rxrpc_local_put,			"PUT") \

	E_(rxrpc_local_queued,			"QUE")



#define rxrpc_peer_traces \

	EM(rxrpc_peer_got,			"GOT") \

	EM(rxrpc_peer_new,			"NEW") \

	EM(rxrpc_peer_processing,		"PRO") \

	EM(rxrpc_peer_put,			"PUT") \

	E_(rxrpc_peer_queued_error,		"QER")



#define rxrpc_conn_traces \

	EM(rxrpc_conn_got,			"GOT") \

	EM(rxrpc_conn_new_client,		"NWc") \
@@ -482,6 +497,33 @@ TRACE_EVENT(rxrpc_local, 
		      __entry->where)

	    );



TRACE_EVENT(rxrpc_peer,

	    TP_PROTO(struct rxrpc_peer *peer, enum rxrpc_peer_trace op,

		     int usage, const void *where),



	    TP_ARGS(peer, op, usage, where),



	    TP_STRUCT__entry(

		    __field(unsigned int,	peer		)

		    __field(int,		op		)

		    __field(int,		usage		)

		    __field(const void *,	where		)

			     ),



	    TP_fast_assign(

		    __entry->peer = peer->debug_id;

		    __entry->op = op;

		    __entry->usage = usage;

		    __entry->where = where;

			   ),



	    TP_printk("P=%08x %s u=%d sp=%pSR",

		      __entry->peer,

		      __print_symbolic(__entry->op, rxrpc_peer_traces),

		      __entry->usage,

		      __entry->where)

	    );



TRACE_EVENT(rxrpc_conn,

	    TP_PROTO(struct rxrpc_connection *conn, enum rxrpc_conn_trace op,

		     int usage, const void *where),

net/rxrpc/ar-internal.h

+4 −19
Original line number Diff line number Diff line
@@ -1041,25 +1041,10 @@ struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *, 
struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *, gfp_t);

struct rxrpc_peer *rxrpc_lookup_incoming_peer(struct rxrpc_local *,

					      struct rxrpc_peer *);



static inline struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *peer)

{

	atomic_inc(&peer->usage);

	return peer;

}



static inline

struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *peer)

{

	return atomic_inc_not_zero(&peer->usage) ? peer : NULL;

}



extern void __rxrpc_put_peer(struct rxrpc_peer *peer);

static inline void rxrpc_put_peer(struct rxrpc_peer *peer)

{

	if (peer && atomic_dec_and_test(&peer->usage))

		__rxrpc_put_peer(peer);

}

struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *);

struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *);

void rxrpc_put_peer(struct rxrpc_peer *);

void __rxrpc_queue_peer_error(struct rxrpc_peer *);



/*

 * proc.c

net/rxrpc/peer_event.c

+1 −1
Original line number Diff line number Diff line
@@ -192,7 +192,7 @@ void rxrpc_error_report(struct sock *sk) 
	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);



	/* The ref we obtained is passed off to the work item */

	rxrpc_queue_work(&peer->error_distributor);

	__rxrpc_queue_peer_error(peer);

	_leave("");

}

net/rxrpc/peer_object.c

+63 −2
Original line number Diff line number Diff line
@@ -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.