[PATCH net-next 12/13] rxrpc: Trace rxrpc_bundle refcount

From: David Howells
Date: Wed Nov 23 2022 - 05:24:18 EST


Add a tracepoint for the rxrpc_bundle refcounting.

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

include/trace/events/rxrpc.h | 34 ++++++++++++++++++++++++++++++++++
net/rxrpc/ar-internal.h | 4 ++--
net/rxrpc/conn_client.c | 27 ++++++++++++++++-----------
net/rxrpc/conn_object.c | 2 +-
net/rxrpc/conn_service.c | 3 ++-
5 files changed, 55 insertions(+), 15 deletions(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 34151d17e7b6..8af077c2927a 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -81,6 +81,15 @@
EM(rxrpc_peer_put_input_error, "PUT inpt-err") \
E_(rxrpc_peer_put_keepalive, "PUT keepaliv")

+#define rxrpc_bundle_traces \
+ EM(rxrpc_bundle_free, "FREE ") \
+ EM(rxrpc_bundle_get_client_call, "GET clt-call") \
+ EM(rxrpc_bundle_get_client_conn, "GET clt-conn") \
+ EM(rxrpc_bundle_get_service_conn, "GET svc-conn") \
+ EM(rxrpc_bundle_put_conn, "PUT conn ") \
+ EM(rxrpc_bundle_put_discard, "PUT discard ") \
+ E_(rxrpc_bundle_new, "NEW ")
+
#define rxrpc_conn_traces \
EM(rxrpc_conn_free, "FREE ") \
EM(rxrpc_conn_get_activate_call, "GET act-call") \
@@ -362,6 +371,7 @@
#define EM(a, b) a,
#define E_(a, b) a

+enum rxrpc_bundle_trace { rxrpc_bundle_traces } __mode(byte);
enum rxrpc_call_trace { rxrpc_call_traces } __mode(byte);
enum rxrpc_client_trace { rxrpc_client_traces } __mode(byte);
enum rxrpc_congest_change { rxrpc_congest_changes } __mode(byte);
@@ -391,6 +401,7 @@ enum rxrpc_txqueue_trace { rxrpc_txqueue_traces } __mode(byte);
#define EM(a, b) TRACE_DEFINE_ENUM(a);
#define E_(a, b) TRACE_DEFINE_ENUM(a);

+rxrpc_bundle_traces;
rxrpc_call_traces;
rxrpc_client_traces;
rxrpc_congest_changes;
@@ -468,6 +479,29 @@ TRACE_EVENT(rxrpc_peer,
__entry->ref)
);

+TRACE_EVENT(rxrpc_bundle,
+ TP_PROTO(unsigned int bundle_debug_id, int ref, enum rxrpc_bundle_trace why),
+
+ TP_ARGS(bundle_debug_id, ref, why),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, bundle )
+ __field(int, ref )
+ __field(int, why )
+ ),
+
+ TP_fast_assign(
+ __entry->bundle = bundle_debug_id;
+ __entry->ref = ref;
+ __entry->why = why;
+ ),
+
+ TP_printk("CB=%08x %s r=%d",
+ __entry->bundle,
+ __print_symbolic(__entry->why, rxrpc_bundle_traces),
+ __entry->ref)
+ );
+
TRACE_EVENT(rxrpc_conn,
TP_PROTO(unsigned int conn_debug_id, int ref, enum rxrpc_conn_trace why),

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 82eb09b961a0..c588c0e81f63 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -875,8 +875,8 @@ extern unsigned long rxrpc_conn_idle_client_fast_expiry;
extern struct idr rxrpc_client_conn_ids;

void rxrpc_destroy_client_conn_ids(void);
-struct rxrpc_bundle *rxrpc_get_bundle(struct rxrpc_bundle *);
-void rxrpc_put_bundle(struct rxrpc_bundle *);
+struct rxrpc_bundle *rxrpc_get_bundle(struct rxrpc_bundle *, enum rxrpc_bundle_trace);
+void rxrpc_put_bundle(struct rxrpc_bundle *, enum rxrpc_bundle_trace);
int rxrpc_connect_call(struct rxrpc_sock *, struct rxrpc_call *,
struct rxrpc_conn_parameters *, struct sockaddr_rxrpc *,
gfp_t);
diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c
index 4352e777aa2a..34ff6fa85c32 100644
--- a/net/rxrpc/conn_client.c
+++ b/net/rxrpc/conn_client.c
@@ -133,31 +133,36 @@ static struct rxrpc_bundle *rxrpc_alloc_bundle(struct rxrpc_conn_parameters *cp,
atomic_set(&bundle->active, 1);
spin_lock_init(&bundle->channel_lock);
INIT_LIST_HEAD(&bundle->waiting_calls);
+ trace_rxrpc_bundle(bundle->debug_id, 1, rxrpc_bundle_new);
}
return bundle;
}

-struct rxrpc_bundle *rxrpc_get_bundle(struct rxrpc_bundle *bundle)
+struct rxrpc_bundle *rxrpc_get_bundle(struct rxrpc_bundle *bundle,
+ enum rxrpc_bundle_trace why)
{
- refcount_inc(&bundle->ref);
+ int r;
+
+ __refcount_inc(&bundle->ref, &r);
+ trace_rxrpc_bundle(bundle->debug_id, r + 1, why);
return bundle;
}

static void rxrpc_free_bundle(struct rxrpc_bundle *bundle)
{
+ trace_rxrpc_bundle(bundle->debug_id, 1, rxrpc_bundle_free);
rxrpc_put_peer(bundle->peer, rxrpc_peer_put_bundle);
kfree(bundle);
}

-void rxrpc_put_bundle(struct rxrpc_bundle *bundle)
+void rxrpc_put_bundle(struct rxrpc_bundle *bundle, enum rxrpc_bundle_trace why)
{
- unsigned int d = bundle->debug_id;
+ unsigned int id = bundle->debug_id;
bool dead;
int r;

dead = __refcount_dec_and_test(&bundle->ref, &r);
-
- _debug("PUT B=%x %d", d, r - 1);
+ trace_rxrpc_bundle(id, r - 1, why);
if (dead)
rxrpc_free_bundle(bundle);
}
@@ -206,7 +211,7 @@ rxrpc_alloc_client_connection(struct rxrpc_bundle *bundle, gfp_t gfp)
list_add_tail(&conn->proc_link, &rxnet->conn_proc_list);
write_unlock(&rxnet->conn_lock);

- rxrpc_get_bundle(bundle);
+ rxrpc_get_bundle(bundle, rxrpc_bundle_get_client_conn);
rxrpc_get_peer(conn->peer, rxrpc_peer_get_client_conn);
rxrpc_get_local(conn->local, rxrpc_local_get_client_conn);
key_get(conn->key);
@@ -342,7 +347,7 @@ static struct rxrpc_bundle *rxrpc_look_up_bundle(struct rxrpc_conn_parameters *c
candidate->debug_id = atomic_inc_return(&rxrpc_bundle_id);
rb_link_node(&candidate->local_node, parent, pp);
rb_insert_color(&candidate->local_node, &local->client_bundles);
- rxrpc_get_bundle(candidate);
+ rxrpc_get_bundle(candidate, rxrpc_bundle_get_client_call);
spin_unlock(&local->client_bundles_lock);
_leave(" = %u [new]", candidate->debug_id);
return candidate;
@@ -350,7 +355,7 @@ static struct rxrpc_bundle *rxrpc_look_up_bundle(struct rxrpc_conn_parameters *c
found_bundle_free:
rxrpc_free_bundle(candidate);
found_bundle:
- rxrpc_get_bundle(bundle);
+ rxrpc_get_bundle(bundle, rxrpc_bundle_get_client_call);
atomic_inc(&bundle->active);
spin_unlock(&local->client_bundles_lock);
_leave(" = %u [found]", bundle->debug_id);
@@ -740,7 +745,7 @@ int rxrpc_connect_call(struct rxrpc_sock *rx,

out_put_bundle:
rxrpc_deactivate_bundle(bundle);
- rxrpc_put_bundle(bundle);
+ rxrpc_put_bundle(bundle, rxrpc_bundle_get_client_call);
out:
_leave(" = %d", ret);
return ret;
@@ -958,7 +963,7 @@ static void rxrpc_deactivate_bundle(struct rxrpc_bundle *bundle)

spin_unlock(&local->client_bundles_lock);
if (need_put)
- rxrpc_put_bundle(bundle);
+ rxrpc_put_bundle(bundle, rxrpc_bundle_put_discard);
}
}

diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
index bbace8d9953d..f7c271a740ed 100644
--- a/net/rxrpc/conn_object.c
+++ b/net/rxrpc/conn_object.c
@@ -363,7 +363,7 @@ static void rxrpc_destroy_connection(struct rcu_head *rcu)

conn->security->clear(conn);
key_put(conn->key);
- rxrpc_put_bundle(conn->bundle);
+ rxrpc_put_bundle(conn->bundle, rxrpc_bundle_put_conn);
rxrpc_put_peer(conn->peer, rxrpc_peer_put_conn);

if (atomic_dec_and_test(&conn->local->rxnet->nr_conns))
diff --git a/net/rxrpc/conn_service.c b/net/rxrpc/conn_service.c
index bf087213bd4d..2c44d67b43dc 100644
--- a/net/rxrpc/conn_service.c
+++ b/net/rxrpc/conn_service.c
@@ -133,7 +133,8 @@ struct rxrpc_connection *rxrpc_prealloc_service_connection(struct rxrpc_net *rxn
*/
conn->state = RXRPC_CONN_SERVICE_PREALLOC;
refcount_set(&conn->ref, 2);
- conn->bundle = rxrpc_get_bundle(&rxrpc_service_dummy_bundle);
+ conn->bundle = rxrpc_get_bundle(&rxrpc_service_dummy_bundle,
+ rxrpc_bundle_get_service_conn);

atomic_inc(&rxnet->nr_conns);
write_lock(&rxnet->conn_lock);