rxrpc: Allocate ACK records at proposal and queue for transmission

Allocate rxrpc_txbuf records for ACKs and put onto a queue for the
transmitter thread to dispatch.

Signed-off-by: David Howells <[email protected]>
cc: Marc Dionne <[email protected]>
cc: [email protected]

Author: dhowells

include/trace/events/rxrpc.h

@@ -34,7 +34,8 @@
 	EM(rxrpc_local_new,			"NEW") \
 	EM(rxrpc_local_processing,		"PRO") \
 	EM(rxrpc_local_put,			"PUT") \
-	E_(rxrpc_local_queued,			"QUE")
+	EM(rxrpc_local_queued,			"QUE") \
+	E_(rxrpc_local_tx_ack,			"TAK")
 
 #define rxrpc_peer_traces \
 	EM(rxrpc_peer_got,			"GOT") \
@@ -258,7 +259,9 @@
 	EM(rxrpc_txbuf_free,			"FREE       ")	\
 	EM(rxrpc_txbuf_get_trans,		"GET TRANS  ")	\
 	EM(rxrpc_txbuf_get_retrans,		"GET RETRANS")	\
+	EM(rxrpc_txbuf_put_ack_tx,		"PUT ACK TX ")	\
 	EM(rxrpc_txbuf_put_cleaned,		"PUT CLEANED")	\
+	EM(rxrpc_txbuf_put_nomem,		"PUT NOMEM  ")	\
 	EM(rxrpc_txbuf_put_rotated,		"PUT ROTATED")	\
 	EM(rxrpc_txbuf_put_send_aborted,	"PUT SEND-X ")	\
 	EM(rxrpc_txbuf_see_send_more,		"SEE SEND+  ")	\
@@ -1095,19 +1098,16 @@ TRACE_EVENT(rxrpc_rx_lose,
 
 TRACE_EVENT(rxrpc_propose_ack,
 	    TP_PROTO(struct rxrpc_call *call, enum rxrpc_propose_ack_trace why,
-		     u8 ack_reason, rxrpc_serial_t serial, bool immediate,
-		     bool background, enum rxrpc_propose_ack_outcome outcome),
+		     u8 ack_reason, rxrpc_serial_t serial,
+		     enum rxrpc_propose_ack_outcome outcome),
 
-	    TP_ARGS(call, why, ack_reason, serial, immediate, background,
-		    outcome),
+	    TP_ARGS(call, why, ack_reason, serial, outcome),
 
 	    TP_STRUCT__entry(
 		    __field(unsigned int,			call		)
 		    __field(enum rxrpc_propose_ack_trace,	why		)
 		    __field(rxrpc_serial_t,			serial		)
 		    __field(u8,					ack_reason	)
-		    __field(bool,				immediate	)
-		    __field(bool,				background	)
 		    __field(enum rxrpc_propose_ack_outcome,	outcome		)
 			     ),
 
@@ -1116,21 +1116,44 @@ TRACE_EVENT(rxrpc_propose_ack,
 		    __entry->why	= why;
 		    __entry->serial	= serial;
 		    __entry->ack_reason	= ack_reason;
-		    __entry->immediate	= immediate;
-		    __entry->background	= background;
 		    __entry->outcome	= outcome;
 			   ),
 
-	    TP_printk("c=%08x %s %s r=%08x i=%u b=%u%s",
+	    TP_printk("c=%08x %s %s r=%08x%s",
 		      __entry->call,
 		      __print_symbolic(__entry->why, rxrpc_propose_ack_traces),
 		      __print_symbolic(__entry->ack_reason, rxrpc_ack_names),
 		      __entry->serial,
-		      __entry->immediate,
-		      __entry->background,
 		      __print_symbolic(__entry->outcome, rxrpc_propose_ack_outcomes))
 	    );
 
+TRACE_EVENT(rxrpc_send_ack,
+	    TP_PROTO(struct rxrpc_call *call, enum rxrpc_propose_ack_trace why,
+		     u8 ack_reason, rxrpc_serial_t serial),
+
+	    TP_ARGS(call, why, ack_reason, serial),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,			call		)
+		    __field(enum rxrpc_propose_ack_trace,	why		)
+		    __field(rxrpc_serial_t,			serial		)
+		    __field(u8,					ack_reason	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->call	= call->debug_id;
+		    __entry->why	= why;
+		    __entry->serial	= serial;
+		    __entry->ack_reason	= ack_reason;
+			   ),
+
+	    TP_printk("c=%08x %s %s r=%08x",
+		      __entry->call,
+		      __print_symbolic(__entry->why, rxrpc_propose_ack_traces),
+		      __print_symbolic(__entry->ack_reason, rxrpc_ack_names),
+		      __entry->serial)
+	    );
+
 TRACE_EVENT(rxrpc_retransmit,
 	    TP_PROTO(struct rxrpc_call *call, rxrpc_seq_t seq, u8 annotation,
 		     s64 expiry),

net/rxrpc/ar-internal.h

@@ -292,6 +292,8 @@ struct rxrpc_local {
 	struct hlist_node	link;
 	struct socket		*socket;	/* my UDP socket */
 	struct work_struct	processor;
+	struct list_head	ack_tx_queue;	/* List of ACKs that need sending */
+	spinlock_t		ack_tx_lock;	/* ACK list lock */
 	struct rxrpc_sock __rcu	*service;	/* Service(s) listening on this endpoint */
 	struct rw_semaphore	defrag_sem;	/* control re-enablement of IP DF bit */
 	struct sk_buff_head	reject_queue;	/* packets awaiting rejection */
@@ -520,10 +522,8 @@ enum rxrpc_call_flag {
  * Events that can be raised on a call.
  */
 enum rxrpc_call_event {
-	RXRPC_CALL_EV_ACK,		/* need to generate ACK */
 	RXRPC_CALL_EV_ABORT,		/* need to generate abort */
 	RXRPC_CALL_EV_RESEND,		/* Tx resend required */
-	RXRPC_CALL_EV_PING,		/* Ping send required */
 	RXRPC_CALL_EV_EXPIRED,		/* Expiry occurred */
 	RXRPC_CALL_EV_ACK_LOST,		/* ACK may be lost, send ping */
 };
@@ -782,13 +782,20 @@ struct rxrpc_txbuf {
 #define RXRPC_TXBUF_LAST	2		/* Set if last packet in Tx phase */
 #define RXRPC_TXBUF_RESENT	3		/* Set if has been resent */
 #define RXRPC_TXBUF_RETRANS	4		/* Set if should be retransmitted */
+	u8 /*enum rxrpc_propose_ack_trace*/ ack_why;	/* If ack, why */
 	struct {
 		/* The packet for encrypting and DMA'ing.  We align it such
 		 * that data[] aligns correctly for any crypto blocksize.
 		 */
 		u8		pad[64 - sizeof(struct rxrpc_wire_header)];
 		struct rxrpc_wire_header wire;	/* Network-ready header */
-		u8		data[RXRPC_JUMBO_DATALEN]; /* Data packet */
+		union {
+			u8	data[RXRPC_JUMBO_DATALEN]; /* Data packet */
+			struct {
+				struct rxrpc_ackpacket ack;
+				u8 acks[0];
+			};
+		};
 	} __aligned(64);
 };
 
@@ -824,8 +831,10 @@ int rxrpc_user_charge_accept(struct rxrpc_sock *, unsigned long);
 /*
  * call_event.c
  */
-void rxrpc_propose_ACK(struct rxrpc_call *, u8, u32, bool, bool,
-		       enum rxrpc_propose_ack_trace);
+void rxrpc_propose_ping(struct rxrpc_call *call, u32 serial,
+			enum rxrpc_propose_ack_trace why);
+void rxrpc_send_ACK(struct rxrpc_call *, u8, rxrpc_serial_t, enum rxrpc_propose_ack_trace);
+void rxrpc_propose_ACK(struct rxrpc_call *, u8, u32, enum rxrpc_propose_ack_trace);
 void rxrpc_process_call(struct work_struct *);
 
 void rxrpc_reduce_call_timer(struct rxrpc_call *call,
@@ -1030,7 +1039,7 @@ static inline struct rxrpc_net *rxrpc_net(struct net *net)
 /*
  * output.c
  */
-int rxrpc_send_ack_packet(struct rxrpc_call *, bool, rxrpc_serial_t *);
+void rxrpc_transmit_ack_packets(struct rxrpc_local *);
 int rxrpc_send_abort_packet(struct rxrpc_call *);
 int rxrpc_send_data_packet(struct rxrpc_call *, struct sk_buff *, bool);
 void rxrpc_reject_packets(struct rxrpc_local *);

net/rxrpc/call_accept.c

@@ -248,9 +248,8 @@ static void rxrpc_send_ping(struct rxrpc_call *call, struct sk_buff *skb)
 
 	if (call->peer->rtt_count < 3 ||
 	    ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), now))
-		rxrpc_propose_ACK(call, RXRPC_ACK_PING, sp->hdr.serial,
-				  true, true,
-				  rxrpc_propose_ack_ping_for_params);
+		rxrpc_send_ACK(call, RXRPC_ACK_PING, sp->hdr.serial,
+			       rxrpc_propose_ack_ping_for_params);
 }
 
 /*