diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index a972887b3f5d..d1213d503f30 100644 --- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -338,8 +338,17 @@ enum rxrpc_conn_flag { RXRPC_CONN_DONT_REUSE, /* Don't reuse this connection */ RXRPC_CONN_COUNTED, /* Counted by rxrpc_nr_client_conns */ RXRPC_CONN_PROBING_FOR_UPGRADE, /* Probing for service upgrade */ + RXRPC_CONN_FINAL_ACK_0, /* Need final ACK for channel 0 */ + RXRPC_CONN_FINAL_ACK_1, /* Need final ACK for channel 1 */ + RXRPC_CONN_FINAL_ACK_2, /* Need final ACK for channel 2 */ + RXRPC_CONN_FINAL_ACK_3, /* Need final ACK for channel 3 */ }; +#define RXRPC_CONN_FINAL_ACK_MASK ((1UL << RXRPC_CONN_FINAL_ACK_0) | \ + (1UL << RXRPC_CONN_FINAL_ACK_1) | \ + (1UL << RXRPC_CONN_FINAL_ACK_2) | \ + (1UL << RXRPC_CONN_FINAL_ACK_3)) + /* * Events that can be raised upon a connection. */ @@ -393,6 +402,7 @@ struct rxrpc_connection { #define RXRPC_ACTIVE_CHANS_MASK ((1 << RXRPC_MAXCALLS) - 1) struct list_head waiting_calls; /* Calls waiting for channels */ struct rxrpc_channel { + unsigned long final_ack_at; /* Time at which to issue final ACK */ struct rxrpc_call __rcu *call; /* Active call */ u32 call_id; /* ID of current call */ u32 call_counter; /* Call ID counter */ @@ -404,6 +414,7 @@ struct rxrpc_connection { }; } channels[RXRPC_MAXCALLS]; + struct timer_list timer; /* Conn event timer */ struct work_struct processor; /* connection event processor */ union { struct rb_node client_node; /* Node in local->client_conns */ @@ -861,6 +872,12 @@ static inline void rxrpc_put_connection(struct rxrpc_connection *conn) rxrpc_put_service_conn(conn); } +static inline void rxrpc_reduce_conn_timer(struct rxrpc_connection *conn, + unsigned long expire_at) +{ + timer_reduce(&conn->timer, expire_at); +} + /* * conn_service.c */ diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c index 5f9624bd311c..cfb997593da9 100644 --- a/net/rxrpc/conn_client.c +++ b/net/rxrpc/conn_client.c @@ -554,6 +554,11 @@ static void rxrpc_activate_one_channel(struct rxrpc_connection *conn, trace_rxrpc_client(conn, channel, rxrpc_client_chan_activate); + /* Cancel the final ACK on the previous call if it hasn't been sent yet + * as the DATA packet will implicitly ACK it. + */ + clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags); + write_lock_bh(&call->state_lock); if (!test_bit(RXRPC_CALL_TX_LASTQ, &call->flags)) call->state = RXRPC_CALL_CLIENT_SEND_REQUEST; @@ -813,6 +818,19 @@ void rxrpc_disconnect_client_call(struct rxrpc_call *call) goto out_2; } + /* Schedule the final ACK to be transmitted in a short while so that it + * can be skipped if we find a follow-on call. The first DATA packet + * of the follow on call will implicitly ACK this call. + */ + if (test_bit(RXRPC_CALL_EXPOSED, &call->flags)) { + unsigned long final_ack_at = jiffies + 2; + + WRITE_ONCE(chan->final_ack_at, final_ack_at); + smp_wmb(); /* vs rxrpc_process_delayed_final_acks() */ + set_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags); + rxrpc_reduce_conn_timer(conn, final_ack_at); + } + /* Things are more complex and we need the cache lock. We might be * able to simply idle the conn or it might now be lurking on the wait * list. It might even get moved back to the active list whilst we're diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c index 59a51a56e7c8..9e9a8db1bc9c 100644 --- a/net/rxrpc/conn_event.c +++ b/net/rxrpc/conn_event.c @@ -24,9 +24,10 @@ * Retransmit terminal ACK or ABORT of the previous call. */ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn, - struct sk_buff *skb) + struct sk_buff *skb, + unsigned int channel) { - struct rxrpc_skb_priv *sp = rxrpc_skb(skb); + struct rxrpc_skb_priv *sp = skb ? rxrpc_skb(skb) : NULL; struct rxrpc_channel *chan; struct msghdr msg; struct kvec iov; @@ -48,7 +49,7 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn, _enter("%d", conn->debug_id); - chan = &conn->channels[sp->hdr.cid & RXRPC_CHANNELMASK]; + chan = &conn->channels[channel]; /* If the last call got moved on whilst we were waiting to run, just * ignore this packet. @@ -56,7 +57,7 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn, call_id = READ_ONCE(chan->last_call); /* Sync with __rxrpc_disconnect_call() */ smp_rmb(); - if (call_id != sp->hdr.callNumber) + if (skb && call_id != sp->hdr.callNumber) return; msg.msg_name = &conn->params.peer->srx.transport; @@ -65,9 +66,9 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn, msg.msg_controllen = 0; msg.msg_flags = 0; - pkt.whdr.epoch = htonl(sp->hdr.epoch); - pkt.whdr.cid = htonl(sp->hdr.cid); - pkt.whdr.callNumber = htonl(sp->hdr.callNumber); + pkt.whdr.epoch = htonl(conn->proto.epoch); + pkt.whdr.cid = htonl(conn->proto.cid); + pkt.whdr.callNumber = htonl(call_id); pkt.whdr.seq = 0; pkt.whdr.type = chan->last_type; pkt.whdr.flags = conn->out_clientflag; @@ -87,11 +88,11 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn, mtu = conn->params.peer->if_mtu; mtu -= conn->params.peer->hdrsize; pkt.ack.bufferSpace = 0; - pkt.ack.maxSkew = htons(skb->priority); - pkt.ack.firstPacket = htonl(chan->last_seq); - pkt.ack.previousPacket = htonl(chan->last_seq - 1); - pkt.ack.serial = htonl(sp->hdr.serial); - pkt.ack.reason = RXRPC_ACK_DUPLICATE; + pkt.ack.maxSkew = htons(skb ? skb->priority : 0); + pkt.ack.firstPacket = htonl(chan->last_seq + 1); + pkt.ack.previousPacket = htonl(chan->last_seq); + pkt.ack.serial = htonl(skb ? sp->hdr.serial : 0); + pkt.ack.reason = skb ? RXRPC_ACK_DUPLICATE : RXRPC_ACK_IDLE; pkt.ack.nAcks = 0; pkt.info.rxMTU = htonl(rxrpc_rx_mtu); pkt.info.maxMTU = htonl(mtu); @@ -272,7 +273,8 @@ static int rxrpc_process_event(struct rxrpc_connection *conn, switch (sp->hdr.type) { case RXRPC_PACKET_TYPE_DATA: case RXRPC_PACKET_TYPE_ACK: - rxrpc_conn_retransmit_call(conn, skb); + rxrpc_conn_retransmit_call(conn, skb, + sp->hdr.cid & RXRPC_CHANNELMASK); return 0; case RXRPC_PACKET_TYPE_BUSY: @@ -378,6 +380,48 @@ static void rxrpc_secure_connection(struct rxrpc_connection *conn) _leave(" [aborted]"); } +/* + * Process delayed final ACKs that we haven't subsumed into a subsequent call. + */ +static void rxrpc_process_delayed_final_acks(struct rxrpc_connection *conn) +{ + unsigned long j = jiffies, next_j; + unsigned int channel; + bool set; + +again: + next_j = j + LONG_MAX; + set = false; + for (channel = 0; channel < RXRPC_MAXCALLS; channel++) { + struct rxrpc_channel *chan = &conn->channels[channel]; + unsigned long ack_at; + + if (!test_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags)) + continue; + + smp_rmb(); /* vs rxrpc_disconnect_client_call */ + ack_at = READ_ONCE(chan->final_ack_at); + + if (time_before(j, ack_at)) { + if (time_before(ack_at, next_j)) { + next_j = ack_at; + set = true; + } + continue; + } + + if (test_and_clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel, + &conn->flags)) + rxrpc_conn_retransmit_call(conn, NULL, channel); + } + + j = jiffies; + if (time_before_eq(next_j, j)) + goto again; + if (set) + rxrpc_reduce_conn_timer(conn, next_j); +} + /* * connection-level event processor */ @@ -394,6 +438,10 @@ void rxrpc_process_connection(struct work_struct *work) if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events)) rxrpc_secure_connection(conn); + /* Process delayed ACKs whose time has come. */ + if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK) + rxrpc_process_delayed_final_acks(conn); + /* go through the conn-level event packets, releasing the ref on this * connection that each one has when we've finished with it */ while ((skb = skb_dequeue(&conn->rx_queue))) { diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c index fe575798592f..a01a3791f06a 100644 --- a/net/rxrpc/conn_object.c +++ b/net/rxrpc/conn_object.c @@ -24,6 +24,14 @@ unsigned int rxrpc_connection_expiry = 10 * 60; static void rxrpc_destroy_connection(struct rcu_head *); +static void rxrpc_connection_timer(struct timer_list *timer) +{ + struct rxrpc_connection *conn = + container_of(timer, struct rxrpc_connection, timer); + + rxrpc_queue_conn(conn); +} + /* * allocate a new connection */ @@ -38,6 +46,7 @@ struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp) INIT_LIST_HEAD(&conn->cache_link); spin_lock_init(&conn->channel_lock); INIT_LIST_HEAD(&conn->waiting_calls); + timer_setup(&conn->timer, &rxrpc_connection_timer, 0); INIT_WORK(&conn->processor, &rxrpc_process_connection); INIT_LIST_HEAD(&conn->proc_link); INIT_LIST_HEAD(&conn->link); @@ -332,6 +341,7 @@ static void rxrpc_destroy_connection(struct rcu_head *rcu) _net("DESTROY CONN %d", conn->debug_id); + del_timer_sync(&conn->timer); rxrpc_purge_queue(&conn->rx_queue); conn->security->clear(conn); diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c index 8510a98b87e1..be0b9ae13893 100644 --- a/net/rxrpc/recvmsg.c +++ b/net/rxrpc/recvmsg.c @@ -144,11 +144,13 @@ static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial) trace_rxrpc_receive(call, rxrpc_receive_end, 0, call->rx_top); ASSERTCMP(call->rx_hard_ack, ==, call->rx_top); +#if 0 // TODO: May want to transmit final ACK under some circumstances anyway if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) { rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, serial, true, false, rxrpc_propose_ack_terminal_ack); rxrpc_send_ack_packet(call, false); } +#endif write_lock_bh(&call->state_lock);