[PATCH net-next 11/35] rxrpc: trace: Don't use __builtin_return_address for rxrpc_conn tracing

From: David Howells
Date: Wed Nov 30 2022 - 11:58:08 EST

In rxrpc tracing, use enums to generate lists of points of interest rather
than __builtin_return_address() for the rxrpc_conn tracepoint

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
cc: linux-afs@xxxxxxxxxxxxxxxxxxx
---

include/trace/events/rxrpc.h | 58 +++++++++++++++++++++++++++---------------
net/rxrpc/ar-internal.h | 21 +++++++++------
net/rxrpc/call_accept.c | 9 ++-----
net/rxrpc/call_object.c | 2 +
net/rxrpc/conn_client.c | 28 ++++++++++----------
net/rxrpc/conn_event.c | 4 +--
net/rxrpc/conn_object.c | 40 +++++++++++++++--------------
net/rxrpc/conn_service.c | 4 +--
net/rxrpc/input.c | 2 +
9 files changed, 92 insertions(+), 76 deletions(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 1c74143a51c1..e09568a8c173 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -82,14 +82,34 @@
E_(rxrpc_peer_put_keepalive, "PUT keepaliv")

#define rxrpc_conn_traces \
- EM(rxrpc_conn_got, "GOT") \
- EM(rxrpc_conn_new_client, "NWc") \
- EM(rxrpc_conn_new_service, "NWs") \
- EM(rxrpc_conn_put_client, "PTc") \
- EM(rxrpc_conn_put_service, "PTs") \
- EM(rxrpc_conn_queued, "QUE") \
- EM(rxrpc_conn_reap_service, "RPs") \
- E_(rxrpc_conn_seen, "SEE")
+ EM(rxrpc_conn_free, "FREE ") \
+ EM(rxrpc_conn_get_activate_call, "GET act-call") \
+ EM(rxrpc_conn_get_call_input, "GET inp-call") \
+ EM(rxrpc_conn_get_conn_input, "GET inp-conn") \
+ EM(rxrpc_conn_get_idle, "GET idle ") \
+ EM(rxrpc_conn_get_poke, "GET poke ") \
+ EM(rxrpc_conn_get_service_conn, "GET svc-conn") \
+ EM(rxrpc_conn_new_client, "NEW client ") \
+ EM(rxrpc_conn_new_service, "NEW service ") \
+ EM(rxrpc_conn_put_already_queued, "PUT alreadyq") \
+ EM(rxrpc_conn_put_call, "PUT call ") \
+ EM(rxrpc_conn_put_call_input, "PUT inp-call") \
+ EM(rxrpc_conn_put_conn_input, "PUT inp-conn") \
+ EM(rxrpc_conn_put_discard, "PUT discard ") \
+ EM(rxrpc_conn_put_discard_idle, "PUT disc-idl") \
+ EM(rxrpc_conn_put_local_dead, "PUT loc-dead") \
+ EM(rxrpc_conn_put_noreuse, "PUT noreuse ") \
+ EM(rxrpc_conn_put_poke, "PUT poke ") \
+ EM(rxrpc_conn_put_unbundle, "PUT unbundle") \
+ EM(rxrpc_conn_put_unidle, "PUT unidle ") \
+ EM(rxrpc_conn_put_work, "PUT work ") \
+ EM(rxrpc_conn_queue_challenge, "GQ chall ") \
+ EM(rxrpc_conn_queue_retry_work, "GQ retry-wk") \
+ EM(rxrpc_conn_queue_rx_work, "GQ rx-work ") \
+ EM(rxrpc_conn_queue_timer, "GQ timer ") \
+ EM(rxrpc_conn_see_new_service_conn, "SEE new-svc ") \
+ EM(rxrpc_conn_see_reap_service, "SEE reap-svc") \
+ E_(rxrpc_conn_see_work, "SEE work ")

#define rxrpc_client_traces \
EM(rxrpc_client_activate_chans, "Activa") \
@@ -430,30 +450,26 @@ TRACE_EVENT(rxrpc_peer,
);

TRACE_EVENT(rxrpc_conn,
- TP_PROTO(unsigned int conn_debug_id, enum rxrpc_conn_trace op,
- int usage, const void *where),
+ TP_PROTO(unsigned int conn_debug_id, int ref, enum rxrpc_conn_trace why),

- TP_ARGS(conn_debug_id, op, usage, where),
+ TP_ARGS(conn_debug_id, ref, why),

TP_STRUCT__entry(
__field(unsigned int, conn )
- __field(int, op )
- __field(int, usage )
- __field(const void *, where )
+ __field(int, ref )
+ __field(int, why )
),

TP_fast_assign(
__entry->conn = conn_debug_id;
- __entry->op = op;
- __entry->usage = usage;
- __entry->where = where;
+ __entry->ref = ref;
+ __entry->why = why;
),

- TP_printk("C=%08x %s u=%d sp=%pSR",
+ TP_printk("C=%08x %s r=%d",
__entry->conn,
- __print_symbolic(__entry->op, rxrpc_conn_traces),
- __entry->usage,
- __entry->where)
+ __print_symbolic(__entry->why, rxrpc_conn_traces),
+ __entry->ref)
);

TRACE_EVENT(rxrpc_client,
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 6cb111e9761c..bc8281c410c5 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -882,7 +882,7 @@ int rxrpc_connect_call(struct rxrpc_sock *, struct rxrpc_call *,
gfp_t);
void rxrpc_expose_client_call(struct rxrpc_call *);
void rxrpc_disconnect_client_call(struct rxrpc_bundle *, struct rxrpc_call *);
-void rxrpc_put_client_conn(struct rxrpc_connection *);
+void rxrpc_put_client_conn(struct rxrpc_connection *, enum rxrpc_conn_trace);
void rxrpc_discard_expired_client_conns(struct work_struct *);
void rxrpc_destroy_all_client_connections(struct rxrpc_net *);
void rxrpc_clean_up_local_conns(struct rxrpc_local *);
@@ -906,11 +906,13 @@ struct rxrpc_connection *rxrpc_find_connection_rcu(struct rxrpc_local *,
void __rxrpc_disconnect_call(struct rxrpc_connection *, struct rxrpc_call *);
void rxrpc_disconnect_call(struct rxrpc_call *);
void rxrpc_kill_connection(struct rxrpc_connection *);
-bool rxrpc_queue_conn(struct rxrpc_connection *);
-void rxrpc_see_connection(struct rxrpc_connection *);
-struct rxrpc_connection *rxrpc_get_connection(struct rxrpc_connection *);
-struct rxrpc_connection *rxrpc_get_connection_maybe(struct rxrpc_connection *);
-void rxrpc_put_service_conn(struct rxrpc_connection *);
+bool rxrpc_queue_conn(struct rxrpc_connection *, enum rxrpc_conn_trace);
+void rxrpc_see_connection(struct rxrpc_connection *, enum rxrpc_conn_trace);
+struct rxrpc_connection *rxrpc_get_connection(struct rxrpc_connection *,
+ enum rxrpc_conn_trace);
+struct rxrpc_connection *rxrpc_get_connection_maybe(struct rxrpc_connection *,
+ enum rxrpc_conn_trace);
+void rxrpc_put_service_conn(struct rxrpc_connection *, enum rxrpc_conn_trace);
void rxrpc_service_connection_reaper(struct work_struct *);
void rxrpc_destroy_all_connections(struct rxrpc_net *);

@@ -924,15 +926,16 @@ static inline bool rxrpc_conn_is_service(const struct rxrpc_connection *conn)
return !rxrpc_conn_is_client(conn);
}

-static inline void rxrpc_put_connection(struct rxrpc_connection *conn)
+static inline void rxrpc_put_connection(struct rxrpc_connection *conn,
+ enum rxrpc_conn_trace why)
{
if (!conn)
return;

if (rxrpc_conn_is_client(conn))
- rxrpc_put_client_conn(conn);
+ rxrpc_put_client_conn(conn, why);
else
- rxrpc_put_service_conn(conn);
+ rxrpc_put_service_conn(conn, why);
}

static inline void rxrpc_reduce_conn_timer(struct rxrpc_connection *conn,
diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c
index f6bc3b07c3e5..04b52e28e0cc 100644
--- a/net/rxrpc/call_accept.c
+++ b/net/rxrpc/call_accept.c
@@ -91,9 +91,6 @@ static int rxrpc_service_prealloc_one(struct rxrpc_sock *rx,
b->conn_backlog[head] = conn;
smp_store_release(&b->conn_backlog_head,
(head + 1) & (size - 1));
-
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_new_service,
- refcount_read(&conn->ref), here);
}

/* Now it gets complicated, because calls get registered with the
@@ -309,10 +306,10 @@ static struct rxrpc_call *rxrpc_alloc_incoming_call(struct rxrpc_sock *rx,
(conn_tail + 1) & (RXRPC_BACKLOG_MAX - 1));
conn->local = rxrpc_get_local(local, rxrpc_local_get_prealloc_conn);
conn->peer = peer;
- rxrpc_see_connection(conn);
+ rxrpc_see_connection(conn, rxrpc_conn_see_new_service_conn);
rxrpc_new_incoming_connection(rx, conn, sec, skb);
} else {
- rxrpc_get_connection(conn);
+ rxrpc_get_connection(conn, rxrpc_conn_get_service_conn);
}

/* And now we can allocate and set up a new call */
@@ -402,7 +399,7 @@ struct rxrpc_call *rxrpc_new_incoming_call(struct rxrpc_local *local,
case RXRPC_CONN_SERVICE_UNSECURED:
conn->state = RXRPC_CONN_SERVICE_CHALLENGING;
set_bit(RXRPC_CONN_EV_CHALLENGE, &call->conn->events);
- rxrpc_queue_conn(call->conn);
+ rxrpc_queue_conn(call->conn, rxrpc_conn_queue_challenge);
break;

case RXRPC_CONN_SERVICE:
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 1b725afd6e2c..29ec4013aa0b 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -635,7 +635,7 @@ static void rxrpc_destroy_call(struct work_struct *work)

rxrpc_delete_call_timer(call);

- rxrpc_put_connection(call->conn);
+ rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
kmem_cache_free(rxrpc_call_jar, call);
if (atomic_dec_and_test(&rxnet->nr_calls))
diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c
index 9444da235a48..dcfec6a45255 100644
--- a/net/rxrpc/conn_client.c
+++ b/net/rxrpc/conn_client.c
@@ -211,9 +211,8 @@ rxrpc_alloc_client_connection(struct rxrpc_bundle *bundle, gfp_t gfp)
rxrpc_get_local(conn->local, rxrpc_local_get_client_conn);
key_get(conn->key);

- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_new_client,
- refcount_read(&conn->ref),
- __builtin_return_address(0));
+ trace_rxrpc_conn(conn->debug_id, refcount_read(&conn->ref),
+ rxrpc_conn_new_client);

atomic_inc(&rxnet->nr_client_conns);
trace_rxrpc_client(conn, -1, rxrpc_client_alloc);
@@ -467,10 +466,10 @@ static void rxrpc_add_conn_to_bundle(struct rxrpc_bundle *bundle, gfp_t gfp)
if (candidate) {
_debug("discard C=%x", candidate->debug_id);
trace_rxrpc_client(candidate, -1, rxrpc_client_duplicate);
- rxrpc_put_connection(candidate);
+ rxrpc_put_connection(candidate, rxrpc_conn_put_discard);
}

- rxrpc_put_connection(old);
+ rxrpc_put_connection(old, rxrpc_conn_put_noreuse);
_leave("");
}

@@ -544,7 +543,7 @@ static void rxrpc_activate_one_channel(struct rxrpc_connection *conn,
rxrpc_see_call(call);
list_del_init(&call->chan_wait_link);
call->peer = rxrpc_get_peer(conn->peer, rxrpc_peer_get_activate_call);
- call->conn = rxrpc_get_connection(conn);
+ call->conn = rxrpc_get_connection(conn, rxrpc_conn_get_activate_call);
call->cid = conn->proto.cid | channel;
call->call_id = call_id;
call->security = conn->security;
@@ -592,7 +591,7 @@ static void rxrpc_unidle_conn(struct rxrpc_bundle *bundle, struct rxrpc_connecti
}
spin_unlock(&rxnet->client_conn_cache_lock);
if (drop_ref)
- rxrpc_put_connection(conn);
+ rxrpc_put_connection(conn, rxrpc_conn_put_unidle);
}
}

@@ -896,7 +895,7 @@ void rxrpc_disconnect_client_call(struct rxrpc_bundle *bundle, struct rxrpc_call
trace_rxrpc_client(conn, channel, rxrpc_client_to_idle);
conn->idle_timestamp = jiffies;

- rxrpc_get_connection(conn);
+ rxrpc_get_connection(conn, rxrpc_conn_get_idle);
spin_lock(&rxnet->client_conn_cache_lock);
list_move_tail(&conn->cache_link, &rxnet->idle_client_conns);
spin_unlock(&rxnet->client_conn_cache_lock);
@@ -938,7 +937,7 @@ static void rxrpc_unbundle_conn(struct rxrpc_connection *conn)

if (need_drop) {
rxrpc_deactivate_bundle(bundle);
- rxrpc_put_connection(conn);
+ rxrpc_put_connection(conn, rxrpc_conn_put_unbundle);
}
}

@@ -983,15 +982,15 @@ static void rxrpc_kill_client_conn(struct rxrpc_connection *conn)
/*
* Clean up a dead client connections.
*/
-void rxrpc_put_client_conn(struct rxrpc_connection *conn)
+void rxrpc_put_client_conn(struct rxrpc_connection *conn,
+ enum rxrpc_conn_trace why)
{
- const void *here = __builtin_return_address(0);
unsigned int debug_id = conn->debug_id;
bool dead;
int r;

dead = __refcount_dec_and_test(&conn->ref, &r);
- trace_rxrpc_conn(debug_id, rxrpc_conn_put_client, r - 1, here);
+ trace_rxrpc_conn(debug_id, r - 1, why);
if (dead)
rxrpc_kill_client_conn(conn);
}
@@ -1063,7 +1062,8 @@ void rxrpc_discard_expired_client_conns(struct work_struct *work)
spin_unlock(&rxnet->client_conn_cache_lock);

rxrpc_unbundle_conn(conn);
- rxrpc_put_connection(conn); /* Drop the ->cache_link ref */
+ /* Drop the ->cache_link ref */
+ rxrpc_put_connection(conn, rxrpc_conn_put_discard_idle);

nr_conns--;
goto next;
@@ -1134,7 +1134,7 @@ void rxrpc_clean_up_local_conns(struct rxrpc_local *local)
struct rxrpc_connection, cache_link);
list_del_init(&conn->cache_link);
rxrpc_unbundle_conn(conn);
- rxrpc_put_connection(conn);
+ rxrpc_put_connection(conn, rxrpc_conn_put_local_dead);
}

_leave(" [culled]");
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 225edaf019f1..817f895c77ca 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -472,14 +472,14 @@ void rxrpc_process_connection(struct work_struct *work)
struct rxrpc_connection *conn =
container_of(work, struct rxrpc_connection, processor);

- rxrpc_see_connection(conn);
+ rxrpc_see_connection(conn, rxrpc_conn_see_work);

if (__rxrpc_use_local(conn->local, rxrpc_local_use_conn_work)) {
rxrpc_do_process_connection(conn);
rxrpc_unuse_local(conn->local, rxrpc_local_unuse_conn_work);
}

- rxrpc_put_connection(conn);
+ rxrpc_put_connection(conn, rxrpc_conn_put_work);
_leave("");
return;
}
diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
index 554ee5dd3325..bbace8d9953d 100644
--- a/net/rxrpc/conn_object.c
+++ b/net/rxrpc/conn_object.c
@@ -26,7 +26,7 @@ static void rxrpc_connection_timer(struct timer_list *timer)
struct rxrpc_connection *conn =
container_of(timer, struct rxrpc_connection, timer);

- rxrpc_queue_conn(conn);
+ rxrpc_queue_conn(conn, rxrpc_conn_queue_timer);
}

/*
@@ -260,43 +260,42 @@ void rxrpc_kill_connection(struct rxrpc_connection *conn)
* Queue a connection's work processor, getting a ref to pass to the work
* queue.
*/
-bool rxrpc_queue_conn(struct rxrpc_connection *conn)
+bool rxrpc_queue_conn(struct rxrpc_connection *conn, enum rxrpc_conn_trace why)
{
- const void *here = __builtin_return_address(0);
int r;

if (!__refcount_inc_not_zero(&conn->ref, &r))
return false;
if (rxrpc_queue_work(&conn->processor))
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_queued, r + 1, here);
+ trace_rxrpc_conn(conn->debug_id, why, r + 1);
else
- rxrpc_put_connection(conn);
+ rxrpc_put_connection(conn, rxrpc_conn_put_already_queued);
return true;
}

/*
* Note the re-emergence of a connection.
*/
-void rxrpc_see_connection(struct rxrpc_connection *conn)
+void rxrpc_see_connection(struct rxrpc_connection *conn,
+ enum rxrpc_conn_trace why)
{
- const void *here = __builtin_return_address(0);
if (conn) {
- int n = refcount_read(&conn->ref);
+ int r = refcount_read(&conn->ref);

- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_seen, n, here);
+ trace_rxrpc_conn(conn->debug_id, r, why);
}
}

/*
* Get a ref on a connection.
*/
-struct rxrpc_connection *rxrpc_get_connection(struct rxrpc_connection *conn)
+struct rxrpc_connection *rxrpc_get_connection(struct rxrpc_connection *conn,
+ enum rxrpc_conn_trace why)
{
- const void *here = __builtin_return_address(0);
int r;

__refcount_inc(&conn->ref, &r);
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_got, r, here);
+ trace_rxrpc_conn(conn->debug_id, r + 1, why);
return conn;
}

@@ -304,14 +303,14 @@ struct rxrpc_connection *rxrpc_get_connection(struct rxrpc_connection *conn)
* Try to get a ref on a connection.
*/
struct rxrpc_connection *
-rxrpc_get_connection_maybe(struct rxrpc_connection *conn)
+rxrpc_get_connection_maybe(struct rxrpc_connection *conn,
+ enum rxrpc_conn_trace why)
{
- const void *here = __builtin_return_address(0);
int r;

if (conn) {
if (__refcount_inc_not_zero(&conn->ref, &r))
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_got, r + 1, here);
+ trace_rxrpc_conn(conn->debug_id, r + 1, why);
else
conn = NULL;
}
@@ -331,14 +330,14 @@ static void rxrpc_set_service_reap_timer(struct rxrpc_net *rxnet,
/*
* Release a service connection
*/
-void rxrpc_put_service_conn(struct rxrpc_connection *conn)
+void rxrpc_put_service_conn(struct rxrpc_connection *conn,
+ enum rxrpc_conn_trace why)
{
- const void *here = __builtin_return_address(0);
unsigned int debug_id = conn->debug_id;
int r;

__refcount_dec(&conn->ref, &r);
- trace_rxrpc_conn(debug_id, rxrpc_conn_put_service, r - 1, here);
+ trace_rxrpc_conn(debug_id, r - 1, why);
if (r - 1 == 1)
rxrpc_set_service_reap_timer(conn->local->rxnet,
jiffies + rxrpc_connection_expiry);
@@ -354,6 +353,9 @@ static void rxrpc_destroy_connection(struct rcu_head *rcu)

_enter("{%d,u=%d}", conn->debug_id, refcount_read(&conn->ref));

+ trace_rxrpc_conn(conn->debug_id, refcount_read(&conn->ref),
+ rxrpc_conn_free);
+
ASSERTCMP(refcount_read(&conn->ref), ==, 0);

del_timer_sync(&conn->timer);
@@ -419,7 +421,7 @@ void rxrpc_service_connection_reaper(struct work_struct *work)
*/
if (!refcount_dec_if_one(&conn->ref))
continue;
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_reap_service, 0, NULL);
+ rxrpc_see_connection(conn, rxrpc_conn_see_reap_service);

if (rxrpc_conn_is_client(conn))
BUG();
diff --git a/net/rxrpc/conn_service.c b/net/rxrpc/conn_service.c
index a3b91864ef21..bf087213bd4d 100644
--- a/net/rxrpc/conn_service.c
+++ b/net/rxrpc/conn_service.c
@@ -141,9 +141,7 @@ struct rxrpc_connection *rxrpc_prealloc_service_connection(struct rxrpc_net *rxn
list_add_tail(&conn->proc_link, &rxnet->conn_proc_list);
write_unlock(&rxnet->conn_lock);

- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_new_service,
- refcount_read(&conn->ref),
- __builtin_return_address(0));
+ rxrpc_see_connection(conn, rxrpc_conn_new_service);
}

return conn;
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index cecfd201d832..c8ff7489b412 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -1121,7 +1121,7 @@ static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
_enter("%p,%p", conn, skb);

skb_queue_tail(&conn->rx_queue, skb);
- rxrpc_queue_conn(conn);
+ rxrpc_queue_conn(conn, rxrpc_conn_queue_rx_work);
}

/*