diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 450b8f345814..e51a84f349d8 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -1152,7 +1152,8 @@ TRACE_EVENT(rxrpc_receive,
 		    __field(enum rxrpc_receive_trace,	why)
 		    __field(rxrpc_serial_t,		serial)
 		    __field(rxrpc_seq_t,		seq)
-		    __field(u64,			window)
+		    __field(rxrpc_seq_t,		window)
+		    __field(rxrpc_seq_t,		wtop)
 			     ),
 
 	    TP_fast_assign(
@@ -1160,7 +1161,8 @@ TRACE_EVENT(rxrpc_receive,
 		    __entry->why = why;
 		    __entry->serial = serial;
 		    __entry->seq = seq;
-		    __entry->window = atomic64_read(&call->ackr_window);
+		    __entry->window = call->ackr_window;
+		    __entry->wtop = call->ackr_wtop;
 			   ),
 
 	    TP_printk("c=%08x %s r=%08x q=%08x w=%08x-%08x",
@@ -1168,8 +1170,8 @@ TRACE_EVENT(rxrpc_receive,
 		      __print_symbolic(__entry->why, rxrpc_receive_traces),
 		      __entry->serial,
 		      __entry->seq,
-		      lower_32_bits(__entry->window),
-		      upper_32_bits(__entry->window))
+		      __entry->window,
+		      __entry->wtop)
 	    );
 
 TRACE_EVENT(rxrpc_recvmsg,
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index bfae4a87626f..2ca99688f7f0 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -692,8 +692,9 @@ struct rxrpc_call {
 	/* Receive-phase ACK management (ACKs we send). */
 	u8			ackr_reason;	/* reason to ACK */
 	rxrpc_serial_t		ackr_serial;	/* serial of packet being ACK'd */
-	atomic64_t		ackr_window;	/* Base (in LSW) and top (in MSW) of SACK window */
-	atomic_t		ackr_nr_unacked; /* Number of unacked packets */
+	rxrpc_seq_t		ackr_window;	/* Base of SACK window */
+	rxrpc_seq_t		ackr_wtop;	/* Base of SACK window */
+	unsigned int		ackr_nr_unacked; /* Number of unacked packets */
 	atomic_t		ackr_nr_consumed; /* Number of packets needing hard ACK */
 	struct {
 #define RXRPC_SACK_SIZE 256
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index cf9799be4286..e363f21a2014 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -498,7 +498,7 @@ bool rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb)
 		rxrpc_send_ACK(call, RXRPC_ACK_IDLE, 0,
 			       rxrpc_propose_ack_rx_idle);
 
-	if (atomic_read(&call->ackr_nr_unacked) > 2) {
+	if (call->ackr_nr_unacked > 2) {
 		if (call->peer->rtt_count < 3)
 			rxrpc_send_ACK(call, RXRPC_ACK_PING, 0,
 				       rxrpc_propose_ack_ping_for_rtt);
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 0012589f2aad..6eaffb0d8fdc 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -167,7 +167,8 @@ struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
 	call->tx_total_len = -1;
 	call->next_rx_timo = 20 * HZ;
 	call->next_req_timo = 1 * HZ;
-	atomic64_set(&call->ackr_window, 0x100000001ULL);
+	call->ackr_window = 1;
+	call->ackr_wtop = 1;
 
 	memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 367927a99881..7e65c7d5bff0 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -338,7 +338,8 @@ static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial)
 static void rxrpc_input_update_ack_window(struct rxrpc_call *call,
 					  rxrpc_seq_t window, rxrpc_seq_t wtop)
 {
-	atomic64_set_release(&call->ackr_window, ((u64)wtop) << 32 | window);
+	call->ackr_window = window;
+	call->ackr_wtop = wtop;
 }
 
 /*
@@ -367,9 +368,8 @@ static void rxrpc_input_data_one(struct rxrpc_call *call, struct sk_buff *skb,
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 	struct sk_buff *oos;
 	rxrpc_serial_t serial = sp->hdr.serial;
-	u64 win = atomic64_read(&call->ackr_window);
-	rxrpc_seq_t window = lower_32_bits(win);
-	rxrpc_seq_t wtop = upper_32_bits(win);
+	rxrpc_seq_t window = call->ackr_window;
+	rxrpc_seq_t wtop = call->ackr_wtop;
 	rxrpc_seq_t wlimit = window + call->rx_winsize - 1;
 	rxrpc_seq_t seq = sp->hdr.seq;
 	bool last = sp->hdr.flags & RXRPC_LAST_PACKET;
@@ -419,7 +419,7 @@ static void rxrpc_input_data_one(struct rxrpc_call *call, struct sk_buff *skb,
 		else if (!skb_queue_empty(&call->rx_oos_queue))
 			ack_reason = RXRPC_ACK_DELAY;
 		else
-			atomic_inc_return(&call->ackr_nr_unacked);
+			call->ackr_nr_unacked++;
 
 		window++;
 		if (after(window, wtop))
@@ -567,8 +567,8 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
 	rxrpc_serial_t serial = sp->hdr.serial;
 	rxrpc_seq_t seq0 = sp->hdr.seq;
 
-	_enter("{%llx,%x},{%u,%x}",
-	       atomic64_read(&call->ackr_window), call->rx_highest_seq,
+	_enter("{%x,%x,%x},{%u,%x}",
+	       call->ackr_window, call->ackr_wtop, call->rx_highest_seq,
 	       skb->len, seq0);
 
 	if (__rxrpc_call_is_complete(call))
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 98b5d0db7761..b6bd5e6ccb4c 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -86,20 +86,18 @@ static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
 	unsigned int qsize;
 	rxrpc_seq_t window, wtop, wrap_point, ix, first;
 	int rsize;
-	u64 wtmp;
 	u32 mtu, jmax;
 	u8 *ackp = txb->acks;
 	u8 sack_buffer[sizeof(call->ackr_sack_table)] __aligned(8);
 
-	atomic_set(&call->ackr_nr_unacked, 0);
+	call->ackr_nr_unacked = 0;
 	atomic_set(&call->ackr_nr_consumed, 0);
 	rxrpc_inc_stat(call->rxnet, stat_tx_ack_fill);
 
 	/* Barrier against rxrpc_input_data(). */
 retry:
-	wtmp   = atomic64_read_acquire(&call->ackr_window);
-	window = lower_32_bits(wtmp);
-	wtop   = upper_32_bits(wtmp);
+	window = call->ackr_window;
+	wtop   = call->ackr_wtop;
 	txb->ack.firstPacket = htonl(window);
 	txb->ack.nAcks = 0;
 
@@ -111,9 +109,8 @@ static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
 		 */
 		memcpy(sack_buffer, call->ackr_sack_table, sizeof(sack_buffer));
 		wrap_point = window + RXRPC_SACK_SIZE - 1;
-		wtmp   = atomic64_read_acquire(&call->ackr_window);
-		window = lower_32_bits(wtmp);
-		wtop   = upper_32_bits(wtmp);
+		window = call->ackr_window;
+		wtop   = call->ackr_wtop;
 		if (after(wtop, wrap_point)) {
 			cond_resched();
 			goto retry;
diff --git a/net/rxrpc/proc.c b/net/rxrpc/proc.c
index 750158a085cd..682636d3b060 100644
--- a/net/rxrpc/proc.c
+++ b/net/rxrpc/proc.c
@@ -55,7 +55,6 @@ static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
 	unsigned long timeout = 0;
 	rxrpc_seq_t acks_hard_ack;
 	char lbuff[50], rbuff[50];
-	u64 wtmp;
 
 	if (v == &rxnet->calls) {
 		seq_puts(seq,
@@ -83,7 +82,6 @@ static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
 	}
 
 	acks_hard_ack = READ_ONCE(call->acks_hard_ack);
-	wtmp   = atomic64_read_acquire(&call->ackr_window);
 	seq_printf(seq,
 		   "UDP   %-47.47s %-47.47s %4x %08x %08x %s %3u"
 		   " %-8.8s %08x %08x %08x %02x %08x %02x %08x %02x %06lx\n",
@@ -98,7 +96,7 @@ static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
 		   call->abort_code,
 		   call->debug_id,
 		   acks_hard_ack, READ_ONCE(call->tx_top) - acks_hard_ack,
-		   lower_32_bits(wtmp), upper_32_bits(wtmp) - lower_32_bits(wtmp),
+		   call->ackr_window, call->ackr_wtop - call->ackr_window,
 		   call->rx_serial,
 		   call->cong_cwnd,
 		   timeout);
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index b7545fdc0401..50d263a6359d 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -95,7 +95,7 @@ static int rxrpc_recvmsg_term(struct rxrpc_call *call, struct msghdr *msg)
 	}
 
 	trace_rxrpc_recvdata(call, rxrpc_recvmsg_terminal,
-			     lower_32_bits(atomic64_read(&call->ackr_window)) - 1,
+			     call->ackr_window - 1,
 			     call->rx_pkt_offset, call->rx_pkt_len, ret);
 	return ret;
 }
@@ -175,13 +175,13 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
 	rx_pkt_len = call->rx_pkt_len;
 
 	if (rxrpc_call_has_failed(call)) {
-		seq = lower_32_bits(atomic64_read(&call->ackr_window)) - 1;
+		seq = call->ackr_window - 1;
 		ret = -EIO;
 		goto done;
 	}
 
 	if (test_bit(RXRPC_CALL_RECVMSG_READ_ALL, &call->flags)) {
-		seq = lower_32_bits(atomic64_read(&call->ackr_window)) - 1;
+		seq = call->ackr_window - 1;
 		ret = 1;
 		goto done;
 	}