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authorDavid S. Miller <davem@davemloft.net>2019-08-09 11:27:17 -0700
committerDavid S. Miller <davem@davemloft.net>2019-08-09 11:27:17 -0700
commit7bac762d8da39ae215171bfa93c6662894ce17dc (patch)
tree68a882926d1b201fedac56de7244320b8b86729a
parent8c25d0887a8bd0e1ca2074ac0c6dff173787a83b (diff)
parente8c3af6bb33a9e4b56920ee00aef92eb5e4cf485 (diff)
Merge tag 'rxrpc-fixes-20190809' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
David Howells says: ==================== Here's a couple of fixes for rxrpc: (1) Fix refcounting of the local endpoint. (2) Don't calculate or report packet skew information. This has been obsolete since AFS 3.1 and so is a waste of resources. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--net/rxrpc/af_rxrpc.c6
-rw-r--r--net/rxrpc/ar-internal.h8
-rw-r--r--net/rxrpc/call_event.c15
-rw-r--r--net/rxrpc/input.c59
-rw-r--r--net/rxrpc/local_object.c86
-rw-r--r--net/rxrpc/output.c3
-rw-r--r--net/rxrpc/recvmsg.c6
7 files changed, 100 insertions, 83 deletions
diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index d09eaf153544..0dbbfd1b6487 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -193,7 +193,7 @@ static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len)
service_in_use:
write_unlock(&local->services_lock);
- rxrpc_put_local(local);
+ rxrpc_unuse_local(local);
ret = -EADDRINUSE;
error_unlock:
release_sock(&rx->sk);
@@ -402,7 +402,7 @@ EXPORT_SYMBOL(rxrpc_kernel_check_life);
*/
void rxrpc_kernel_probe_life(struct socket *sock, struct rxrpc_call *call)
{
- rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, false,
+ rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, true, false,
rxrpc_propose_ack_ping_for_check_life);
rxrpc_send_ack_packet(call, true, NULL);
}
@@ -901,7 +901,7 @@ static int rxrpc_release_sock(struct sock *sk)
rxrpc_queue_work(&rxnet->service_conn_reaper);
rxrpc_queue_work(&rxnet->client_conn_reaper);
- rxrpc_put_local(rx->local);
+ rxrpc_unuse_local(rx->local);
rx->local = NULL;
key_put(rx->key);
rx->key = NULL;
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 822f45386e31..145335611af6 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -254,7 +254,8 @@ struct rxrpc_security {
*/
struct rxrpc_local {
struct rcu_head rcu;
- atomic_t usage;
+ atomic_t active_users; /* Number of users of the local endpoint */
+ atomic_t usage; /* Number of references to the structure */
struct rxrpc_net *rxnet; /* The network ns in which this resides */
struct list_head link;
struct socket *socket; /* my UDP socket */
@@ -649,7 +650,6 @@ struct rxrpc_call {
/* receive-phase ACK management */
u8 ackr_reason; /* reason to ACK */
- u16 ackr_skew; /* skew on packet being ACK'd */
rxrpc_serial_t ackr_serial; /* serial of packet being ACK'd */
rxrpc_serial_t ackr_first_seq; /* first sequence number received */
rxrpc_seq_t ackr_prev_seq; /* previous sequence number received */
@@ -743,7 +743,7 @@ int rxrpc_reject_call(struct rxrpc_sock *);
/*
* call_event.c
*/
-void rxrpc_propose_ACK(struct rxrpc_call *, u8, u16, u32, bool, bool,
+void rxrpc_propose_ACK(struct rxrpc_call *, u8, u32, bool, bool,
enum rxrpc_propose_ack_trace);
void rxrpc_process_call(struct work_struct *);
@@ -1002,6 +1002,8 @@ struct rxrpc_local *rxrpc_lookup_local(struct net *, const struct sockaddr_rxrpc
struct rxrpc_local *rxrpc_get_local(struct rxrpc_local *);
struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *);
void rxrpc_put_local(struct rxrpc_local *);
+struct rxrpc_local *rxrpc_use_local(struct rxrpc_local *);
+void rxrpc_unuse_local(struct rxrpc_local *);
void rxrpc_queue_local(struct rxrpc_local *);
void rxrpc_destroy_all_locals(struct rxrpc_net *);
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index bc2adeb3acb9..c767679bfa5d 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -43,8 +43,7 @@ static void rxrpc_propose_ping(struct rxrpc_call *call,
* propose an ACK be sent
*/
static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
- u16 skew, u32 serial, bool immediate,
- bool background,
+ u32 serial, bool immediate, bool background,
enum rxrpc_propose_ack_trace why)
{
enum rxrpc_propose_ack_outcome outcome = rxrpc_propose_ack_use;
@@ -69,14 +68,12 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
if (RXRPC_ACK_UPDATEABLE & (1 << ack_reason)) {
outcome = rxrpc_propose_ack_update;
call->ackr_serial = serial;
- call->ackr_skew = skew;
}
if (!immediate)
goto trace;
} else if (prior > rxrpc_ack_priority[call->ackr_reason]) {
call->ackr_reason = ack_reason;
call->ackr_serial = serial;
- call->ackr_skew = skew;
} else {
outcome = rxrpc_propose_ack_subsume;
}
@@ -137,11 +134,11 @@ trace:
* propose an ACK be sent, locking the call structure
*/
void rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason,
- u16 skew, u32 serial, bool immediate, bool background,
+ u32 serial, bool immediate, bool background,
enum rxrpc_propose_ack_trace why)
{
spin_lock_bh(&call->lock);
- __rxrpc_propose_ACK(call, ack_reason, skew, serial,
+ __rxrpc_propose_ACK(call, ack_reason, serial,
immediate, background, why);
spin_unlock_bh(&call->lock);
}
@@ -239,7 +236,7 @@ static void rxrpc_resend(struct rxrpc_call *call, unsigned long now_j)
ack_ts = ktime_sub(now, call->acks_latest_ts);
if (ktime_to_ns(ack_ts) < call->peer->rtt)
goto out;
- rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, false,
+ rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, true, false,
rxrpc_propose_ack_ping_for_lost_ack);
rxrpc_send_ack_packet(call, true, NULL);
goto out;
@@ -372,7 +369,7 @@ recheck_state:
if (time_after_eq(now, t)) {
trace_rxrpc_timer(call, rxrpc_timer_exp_keepalive, now);
cmpxchg(&call->keepalive_at, t, now + MAX_JIFFY_OFFSET);
- rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, true,
+ rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, true, true,
rxrpc_propose_ack_ping_for_keepalive);
set_bit(RXRPC_CALL_EV_PING, &call->events);
}
@@ -407,7 +404,7 @@ recheck_state:
send_ack = NULL;
if (test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events)) {
call->acks_lost_top = call->tx_top;
- rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, false,
+ rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, true, false,
rxrpc_propose_ack_ping_for_lost_ack);
send_ack = &call->acks_lost_ping;
}
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 5bd6f1546e5c..dd47d465d1d3 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -196,15 +196,14 @@ send_extra_data:
* Ping the other end to fill our RTT cache and to retrieve the rwind
* and MTU parameters.
*/
-static void rxrpc_send_ping(struct rxrpc_call *call, struct sk_buff *skb,
- int skew)
+static void rxrpc_send_ping(struct rxrpc_call *call, struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
ktime_t now = skb->tstamp;
if (call->peer->rtt_usage < 3 ||
ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), now))
- rxrpc_propose_ACK(call, RXRPC_ACK_PING, skew, sp->hdr.serial,
+ rxrpc_propose_ACK(call, RXRPC_ACK_PING, sp->hdr.serial,
true, true,
rxrpc_propose_ack_ping_for_params);
}
@@ -419,8 +418,7 @@ static void rxrpc_input_dup_data(struct rxrpc_call *call, rxrpc_seq_t seq,
/*
* Process a DATA packet, adding the packet to the Rx ring.
*/
-static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb,
- u16 skew)
+static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
enum rxrpc_call_state state;
@@ -600,11 +598,11 @@ skip:
ack:
if (ack)
- rxrpc_propose_ACK(call, ack, skew, ack_serial,
+ rxrpc_propose_ACK(call, ack, ack_serial,
immediate_ack, true,
rxrpc_propose_ack_input_data);
else
- rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, skew, serial,
+ rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, serial,
false, true,
rxrpc_propose_ack_input_data);
@@ -822,8 +820,7 @@ static void rxrpc_input_soft_acks(struct rxrpc_call *call, u8 *acks,
* soft-ACK means that the packet may be discarded and retransmission
* requested. A phase is complete when all packets are hard-ACK'd.
*/
-static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb,
- u16 skew)
+static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
{
struct rxrpc_ack_summary summary = { 0 };
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
@@ -867,11 +864,11 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb,
if (buf.ack.reason == RXRPC_ACK_PING) {
_proto("Rx ACK %%%u PING Request", sp->hdr.serial);
rxrpc_propose_ACK(call, RXRPC_ACK_PING_RESPONSE,
- skew, sp->hdr.serial, true, true,
+ sp->hdr.serial, true, true,
rxrpc_propose_ack_respond_to_ping);
} else if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED,
- skew, sp->hdr.serial, true, true,
+ sp->hdr.serial, true, true,
rxrpc_propose_ack_respond_to_ack);
}
@@ -948,7 +945,7 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb,
RXRPC_TX_ANNO_LAST &&
summary.nr_acks == call->tx_top - hard_ack &&
rxrpc_is_client_call(call))
- rxrpc_propose_ACK(call, RXRPC_ACK_PING, skew, sp->hdr.serial,
+ rxrpc_propose_ACK(call, RXRPC_ACK_PING, sp->hdr.serial,
false, true,
rxrpc_propose_ack_ping_for_lost_reply);
@@ -1004,7 +1001,7 @@ static void rxrpc_input_abort(struct rxrpc_call *call, struct sk_buff *skb)
* Process an incoming call packet.
*/
static void rxrpc_input_call_packet(struct rxrpc_call *call,
- struct sk_buff *skb, u16 skew)
+ struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
unsigned long timo;
@@ -1023,11 +1020,11 @@ static void rxrpc_input_call_packet(struct rxrpc_call *call,
switch (sp->hdr.type) {
case RXRPC_PACKET_TYPE_DATA:
- rxrpc_input_data(call, skb, skew);
+ rxrpc_input_data(call, skb);
break;
case RXRPC_PACKET_TYPE_ACK:
- rxrpc_input_ack(call, skb, skew);
+ rxrpc_input_ack(call, skb);
break;
case RXRPC_PACKET_TYPE_BUSY:
@@ -1108,8 +1105,12 @@ static void rxrpc_post_packet_to_local(struct rxrpc_local *local,
{
_enter("%p,%p", local, skb);
- skb_queue_tail(&local->event_queue, skb);
- rxrpc_queue_local(local);
+ if (rxrpc_get_local_maybe(local)) {
+ skb_queue_tail(&local->event_queue, skb);
+ rxrpc_queue_local(local);
+ } else {
+ rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ }
}
/*
@@ -1119,8 +1120,12 @@ static void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb)
{
CHECK_SLAB_OKAY(&local->usage);
- skb_queue_tail(&local->reject_queue, skb);
- rxrpc_queue_local(local);
+ if (rxrpc_get_local_maybe(local)) {
+ skb_queue_tail(&local->reject_queue, skb);
+ rxrpc_queue_local(local);
+ } else {
+ rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ }
}
/*
@@ -1173,7 +1178,6 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
struct rxrpc_peer *peer = NULL;
struct rxrpc_sock *rx = NULL;
unsigned int channel;
- int skew = 0;
_enter("%p", udp_sk);
@@ -1301,15 +1305,8 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
goto out;
}
- /* Note the serial number skew here */
- skew = (int)sp->hdr.serial - (int)conn->hi_serial;
- if (skew >= 0) {
- if (skew > 0)
- conn->hi_serial = sp->hdr.serial;
- } else {
- skew = -skew;
- skew = min(skew, 65535);
- }
+ if ((int)sp->hdr.serial - (int)conn->hi_serial > 0)
+ conn->hi_serial = sp->hdr.serial;
/* Call-bound packets are routed by connection channel. */
channel = sp->hdr.cid & RXRPC_CHANNELMASK;
@@ -1372,11 +1369,11 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
call = rxrpc_new_incoming_call(local, rx, skb);
if (!call)
goto reject_packet;
- rxrpc_send_ping(call, skb, skew);
+ rxrpc_send_ping(call, skb);
mutex_unlock(&call->user_mutex);
}
- rxrpc_input_call_packet(call, skb, skew);
+ rxrpc_input_call_packet(call, skb);
goto discard;
discard:
diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
index b1c71bad510b..9798159ee65f 100644
--- a/net/rxrpc/local_object.c
+++ b/net/rxrpc/local_object.c
@@ -79,6 +79,7 @@ static struct rxrpc_local *rxrpc_alloc_local(struct rxrpc_net *rxnet,
local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
if (local) {
atomic_set(&local->usage, 1);
+ atomic_set(&local->active_users, 1);
local->rxnet = rxnet;
INIT_LIST_HEAD(&local->link);
INIT_WORK(&local->processor, rxrpc_local_processor);
@@ -266,11 +267,8 @@ struct rxrpc_local *rxrpc_lookup_local(struct net *net,
* bind the transport socket may still fail if we're attempting
* to use a local address that the dying object is still using.
*/
- if (!rxrpc_get_local_maybe(local)) {
- cursor = cursor->next;
- list_del_init(&local->link);
+ if (!rxrpc_use_local(local))
break;
- }
age = "old";
goto found;
@@ -284,7 +282,10 @@ struct rxrpc_local *rxrpc_lookup_local(struct net *net,
if (ret < 0)
goto sock_error;
- list_add_tail(&local->link, cursor);
+ if (cursor != &rxnet->local_endpoints)
+ list_replace(cursor, &local->link);
+ else
+ list_add_tail(&local->link, cursor);
age = "new";
found:
@@ -342,7 +343,8 @@ struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *local)
}
/*
- * Queue a local endpoint.
+ * Queue a local endpoint unless it has become unreferenced and pass the
+ * caller's reference to the work item.
*/
void rxrpc_queue_local(struct rxrpc_local *local)
{
@@ -351,15 +353,8 @@ void rxrpc_queue_local(struct rxrpc_local *local)
if (rxrpc_queue_work(&local->processor))
trace_rxrpc_local(local, rxrpc_local_queued,
atomic_read(&local->usage), here);
-}
-
-/*
- * A local endpoint reached its end of life.
- */
-static void __rxrpc_put_local(struct rxrpc_local *local)
-{
- _enter("%d", local->debug_id);
- rxrpc_queue_work(&local->processor);
+ else
+ rxrpc_put_local(local);
}
/*
@@ -375,11 +370,46 @@ void rxrpc_put_local(struct rxrpc_local *local)
trace_rxrpc_local(local, rxrpc_local_put, n, here);
if (n == 0)
- __rxrpc_put_local(local);
+ call_rcu(&local->rcu, rxrpc_local_rcu);
}
}
/*
+ * Start using a local endpoint.
+ */
+struct rxrpc_local *rxrpc_use_local(struct rxrpc_local *local)
+{
+ unsigned int au;
+
+ local = rxrpc_get_local_maybe(local);
+ if (!local)
+ return NULL;
+
+ au = atomic_fetch_add_unless(&local->active_users, 1, 0);
+ if (au == 0) {
+ rxrpc_put_local(local);
+ return NULL;
+ }
+
+ return local;
+}
+
+/*
+ * Cease using a local endpoint. Once the number of active users reaches 0, we
+ * start the closure of the transport in the work processor.
+ */
+void rxrpc_unuse_local(struct rxrpc_local *local)
+{
+ unsigned int au;
+
+ au = atomic_dec_return(&local->active_users);
+ if (au == 0)
+ rxrpc_queue_local(local);
+ else
+ rxrpc_put_local(local);
+}
+
+/*
* Destroy a local endpoint's socket and then hand the record to RCU to dispose
* of.
*
@@ -393,16 +423,6 @@ static void rxrpc_local_destroyer(struct rxrpc_local *local)
_enter("%d", local->debug_id);
- /* We can get a race between an incoming call packet queueing the
- * processor again and the work processor starting the destruction
- * process which will shut down the UDP socket.
- */
- if (local->dead) {
- _leave(" [already dead]");
- return;
- }
- local->dead = true;
-
mutex_lock(&rxnet->local_mutex);
list_del_init(&local->link);
mutex_unlock(&rxnet->local_mutex);
@@ -422,13 +442,11 @@ static void rxrpc_local_destroyer(struct rxrpc_local *local)
*/
rxrpc_purge_queue(&local->reject_queue);
rxrpc_purge_queue(&local->event_queue);
-
- _debug("rcu local %d", local->debug_id);
- call_rcu(&local->rcu, rxrpc_local_rcu);
}
/*
- * Process events on an endpoint
+ * Process events on an endpoint. The work item carries a ref which
+ * we must release.
*/
static void rxrpc_local_processor(struct work_struct *work)
{
@@ -441,8 +459,10 @@ static void rxrpc_local_processor(struct work_struct *work)
do {
again = false;
- if (atomic_read(&local->usage) == 0)
- return rxrpc_local_destroyer(local);
+ if (atomic_read(&local->active_users) == 0) {
+ rxrpc_local_destroyer(local);
+ break;
+ }
if (!skb_queue_empty(&local->reject_queue)) {
rxrpc_reject_packets(local);
@@ -454,6 +474,8 @@ static void rxrpc_local_processor(struct work_struct *work)
again = true;
}
} while (again);
+
+ rxrpc_put_local(local);
}
/*
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 948e3fe249ec..369e516c4bdf 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -87,7 +87,7 @@ static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
*_top = top;
pkt->ack.bufferSpace = htons(8);
- pkt->ack.maxSkew = htons(call->ackr_skew);
+ pkt->ack.maxSkew = htons(0);
pkt->ack.firstPacket = htonl(hard_ack + 1);
pkt->ack.previousPacket = htonl(call->ackr_prev_seq);
pkt->ack.serial = htonl(serial);
@@ -228,7 +228,6 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping,
if (ping)
clear_bit(RXRPC_CALL_PINGING, &call->flags);
rxrpc_propose_ACK(call, pkt->ack.reason,
- ntohs(pkt->ack.maxSkew),
ntohl(pkt->ack.serial),
false, true,
rxrpc_propose_ack_retry_tx);
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 5abf46cf9e6c..9a7e1bc9791d 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -141,7 +141,7 @@ static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial)
ASSERTCMP(call->rx_hard_ack, ==, call->rx_top);
if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) {
- rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, serial, false, true,
+ rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, serial, false, true,
rxrpc_propose_ack_terminal_ack);
//rxrpc_send_ack_packet(call, false, NULL);
}
@@ -159,7 +159,7 @@ static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial)
call->state = RXRPC_CALL_SERVER_ACK_REQUEST;
call->expect_req_by = jiffies + MAX_JIFFY_OFFSET;
write_unlock_bh(&call->state_lock);
- rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, false, true,
+ rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, serial, false, true,
rxrpc_propose_ack_processing_op);
break;
default:
@@ -212,7 +212,7 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
if (after_eq(hard_ack, call->ackr_consumed + 2) ||
after_eq(top, call->ackr_seen + 2) ||
(hard_ack == top && after(hard_ack, call->ackr_consumed)))
- rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial,
+ rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, serial,
true, true,
rxrpc_propose_ack_rotate_rx);
if (call->ackr_reason && call->ackr_reason != RXRPC_ACK_DELAY)