[PATCH net-next v3 02/21] rxrpc: Convert rxrpc_txbuf::flags into a mask and don't use atomics

David Howells
2024-03-06T00:07:09Z

Convert the transmission buffer flags into a mask and use | and & rather
than bitops functions (atomic ops are not required as only the I/O thread
can manipulate them once submitted for transmission).

The bottom byte can then correspond directly to the Rx protocol header
flags.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: netdev@vger.kernel.org
---
include/trace/events/rxrpc.h | 12 +++++-------
net/rxrpc/ar-internal.h | 8 ++++----
net/rxrpc/call_event.c | 8 ++++----
net/rxrpc/input.c | 2 +-
net/rxrpc/output.c | 27 +++++++++++++--------------
net/rxrpc/sendmsg.c | 10 ++++------
net/rxrpc/txbuf.c | 4 ++--
7 files changed, 33 insertions(+), 38 deletions(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 9add56980485..33888f688325 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -1084,9 +1084,9 @@ TRACE_EVENT(rxrpc_tx_packet,

TRACE_EVENT(rxrpc_tx_data,
TP_PROTO(struct rxrpc_call *call, rxrpc_seq_t seq,
- rxrpc_serial_t serial, u8 flags, bool retrans, bool lose),
+ rxrpc_serial_t serial, unsigned int flags, bool lose),

- TP_ARGS(call, seq, serial, flags, retrans, lose),
+ TP_ARGS(call, seq, serial, flags, lose),

TP_STRUCT__entry(
__field(unsigned int, call)
@@ -1094,8 +1094,7 @@ TRACE_EVENT(rxrpc_tx_data,
__field(rxrpc_serial_t, serial)
__field(u32, cid)
__field(u32, call_id)
- __field(u8, flags)
- __field(bool, retrans)
+ __field(u16, flags)
__field(bool, lose)
),

@@ -1106,7 +1105,6 @@ TRACE_EVENT(rxrpc_tx_data,
__entry->seq = seq;
__entry->serial = serial;
__entry->flags = flags;
- __entry->retrans = retrans;
__entry->lose = lose;
),

@@ -1116,8 +1114,8 @@ TRACE_EVENT(rxrpc_tx_data,
__entry->call_id,
__entry->serial,
__entry->seq,
- __entry->flags,
- __entry->retrans ? " *RETRANS*" : "",
+ __entry->flags & RXRPC_TXBUF_WIRE_FLAGS,
+ __entry->flags & RXRPC_TXBUF_RESENT ? " *RETRANS*" : "",
__entry->lose ? " *LOSE*" : "")
);

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index f76125755810..54d1dc97cb0f 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -800,9 +800,9 @@ struct rxrpc_txbuf {
unsigned int len; /* Amount of data in buffer */
unsigned int space; /* Remaining data space */
unsigned int offset; /* Offset of fill point */
- unsigned long flags;
-#define RXRPC_TXBUF_LAST 0 /* Set if last packet in Tx phase */
-#define RXRPC_TXBUF_RESENT 1 /* Set if has been resent */
+ unsigned int flags;
+#define RXRPC_TXBUF_WIRE_FLAGS 0xff /* The wire protocol flags */
+#define RXRPC_TXBUF_RESENT 0x100 /* Set if has been resent */
u8 /*enum rxrpc_propose_ack_trace*/ ack_why; /* If ack, why */
struct {
/* The packet for encrypting and DMA'ing. We align it such
@@ -822,7 +822,7 @@ struct rxrpc_txbuf {

static inline bool rxrpc_sending_to_server(const struct rxrpc_txbuf *txb)
{
- return txb->wire.flags & RXRPC_CLIENT_INITIATED;
+ return txb->flags & RXRPC_CLIENT_INITIATED;
}

static inline bool rxrpc_sending_to_client(const struct rxrpc_txbuf *txb)
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index a4c309976719..77eacbfc5d45 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -84,7 +84,7 @@ void rxrpc_send_ACK(struct rxrpc_call *call, u8 ack_reason,
txb->ack_why = why;
txb->wire.seq = 0;
txb->wire.type = RXRPC_PACKET_TYPE_ACK;
- txb->wire.flags |= RXRPC_SLOW_START_OK;
+ txb->flags |= RXRPC_SLOW_START_OK;
txb->ack.bufferSpace = 0;
txb->ack.maxSkew = 0;
txb->ack.firstPacket = 0;
@@ -167,7 +167,7 @@ void rxrpc_resend(struct rxrpc_call *call, struct sk_buff *ack_skb)

if (list_empty(&txb->tx_link)) {
list_add_tail(&txb->tx_link, &retrans_queue);
- set_bit(RXRPC_TXBUF_RESENT, &txb->flags);
+ txb->flags |= RXRPC_TXBUF_RESENT;
}

trace_rxrpc_retransmit(call, txb->seq, txb->serial,
@@ -210,7 +210,7 @@ void rxrpc_resend(struct rxrpc_call *call, struct sk_buff *ack_skb)
unacked = true;
if (list_empty(&txb->tx_link)) {
list_add_tail(&txb->tx_link, &retrans_queue);
- set_bit(RXRPC_TXBUF_RESENT, &txb->flags);
+ txb->flags |= RXRPC_TXBUF_RESENT;
rxrpc_inc_stat(call->rxnet, stat_tx_data_retrans);
}
}
@@ -320,7 +320,7 @@ static void rxrpc_decant_prepared_tx(struct rxrpc_call *call)
call->tx_top = txb->seq;
list_add_tail(&txb->call_link, &call->tx_buffer);

- if (txb->wire.flags & RXRPC_LAST_PACKET)
+ if (txb->flags & RXRPC_LAST_PACKET)
rxrpc_close_tx_phase(call);

rxrpc_transmit_one(call, txb);
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 9691de00ade7..c435b50c33f4 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -212,7 +212,7 @@ static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
list_for_each_entry_rcu(txb, &call->tx_buffer, call_link, false) {
if (before_eq(txb->seq, call->acks_hard_ack))
continue;
- if (test_bit(RXRPC_TXBUF_LAST, &txb->flags)) {
+ if (txb->flags & RXRPC_LAST_PACKET) {
set_bit(RXRPC_CALL_TX_LAST, &call->flags);
rot_last = true;
}
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index bad96a983e12..8344ece5358a 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -205,7 +205,8 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
msg.msg_flags = 0;

if (txb->ack.reason == RXRPC_ACK_PING)
- txb->wire.flags |= RXRPC_REQUEST_ACK;
+ txb->flags |= RXRPC_REQUEST_ACK;
+ txb->wire.flags = txb->flags & RXRPC_TXBUF_WIRE_FLAGS;

n = rxrpc_fill_out_ack(conn, call, txb, &rwind);
if (n == 0)
@@ -239,7 +240,7 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
} else {
trace_rxrpc_tx_packet(call->debug_id, &txb->wire,
rxrpc_tx_point_call_ack);
- if (txb->wire.flags & RXRPC_REQUEST_ACK)
+ if (txb->flags & RXRPC_REQUEST_ACK)
call->peer->rtt_last_req = ktime_get_real();
}
rxrpc_tx_backoff(call, ret);
@@ -357,13 +358,13 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
* service call, lest OpenAFS incorrectly send us an ACK with some
* soft-ACKs in it and then never follow up with a proper hard ACK.
*/
- if (txb->wire.flags & RXRPC_REQUEST_ACK)
+ if (txb->flags & RXRPC_REQUEST_ACK)
why = rxrpc_reqack_already_on;
- else if (test_bit(RXRPC_TXBUF_LAST, &txb->flags) && rxrpc_sending_to_client(txb))
+ else if ((txb->flags & RXRPC_LAST_PACKET) && rxrpc_sending_to_client(txb))
why = rxrpc_reqack_no_srv_last;
else if (test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events))
why = rxrpc_reqack_ack_lost;
- else if (test_bit(RXRPC_TXBUF_RESENT, &txb->flags))
+ else if (txb->flags & RXRPC_TXBUF_RESENT)
why = rxrpc_reqack_retrans;
else if (call->cong_mode == RXRPC_CALL_SLOW_START && call->cong_cwnd <= 2)
why = rxrpc_reqack_slow_start;
@@ -379,7 +380,7 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
rxrpc_inc_stat(call->rxnet, stat_why_req_ack[why]);
trace_rxrpc_req_ack(call->debug_id, txb->seq, why);
if (why != rxrpc_reqack_no_srv_last)
- txb->wire.flags |= RXRPC_REQUEST_ACK;
+ txb->flags |= RXRPC_REQUEST_ACK;
dont_set_request_ack:

if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
@@ -387,15 +388,12 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
if ((lose++ & 7) == 7) {
ret = 0;
trace_rxrpc_tx_data(call, txb->seq, txb->serial,
- txb->wire.flags,
- test_bit(RXRPC_TXBUF_RESENT, &txb->flags),
- true);
+ txb->flags, true);
goto done;
}
}

- trace_rxrpc_tx_data(call, txb->seq, txb->serial, txb->wire.flags,
- test_bit(RXRPC_TXBUF_RESENT, &txb->flags), false);
+ trace_rxrpc_tx_data(call, txb->seq, txb->serial, txb->flags, false);

/* Track what we've attempted to transmit at least once so that the
* retransmission algorithm doesn't try to resend what we haven't sent
@@ -411,8 +409,9 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
if (txb->len >= call->peer->maxdata)
goto send_fragmentable;

+ txb->wire.flags = txb->flags & RXRPC_TXBUF_WIRE_FLAGS;
txb->last_sent = ktime_get_real();
- if (txb->wire.flags & RXRPC_REQUEST_ACK)
+ if (txb->flags & RXRPC_REQUEST_ACK)
rtt_slot = rxrpc_begin_rtt_probe(call, txb->serial, rxrpc_rtt_tx_data);

/* send the packet by UDP
@@ -442,7 +441,7 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
done:
if (ret >= 0) {
call->tx_last_sent = txb->last_sent;
- if (txb->wire.flags & RXRPC_REQUEST_ACK) {
+ if (txb->flags & RXRPC_REQUEST_ACK) {
call->peer->rtt_last_req = txb->last_sent;
if (call->peer->rtt_count > 1) {
unsigned long nowj = jiffies, ack_lost_at;
@@ -486,7 +485,7 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
_debug("send fragment");

txb->last_sent = ktime_get_real();
- if (txb->wire.flags & RXRPC_REQUEST_ACK)
+ if (txb->flags & RXRPC_REQUEST_ACK)
rtt_slot = rxrpc_begin_rtt_probe(call, txb->serial, rxrpc_rtt_tx_data);

switch (conn->local->srx.transport.family) {
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 5677d5690a02..25c7c1d4f4c6 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -240,7 +240,7 @@ static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
rxrpc_notify_end_tx_t notify_end_tx)
{
rxrpc_seq_t seq = txb->seq;
- bool last = test_bit(RXRPC_TXBUF_LAST, &txb->flags), poke;
+ bool poke, last = txb->flags & RXRPC_LAST_PACKET;

rxrpc_inc_stat(call->rxnet, stat_tx_data);

@@ -394,13 +394,11 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
/* add the packet to the send queue if it's now full */
if (!txb->space ||
(msg_data_left(msg) == 0 && !more)) {
- if (msg_data_left(msg) == 0 && !more) {
- txb->wire.flags |= RXRPC_LAST_PACKET;
- __set_bit(RXRPC_TXBUF_LAST, &txb->flags);
- }
+ if (msg_data_left(msg) == 0 && !more)
+ txb->flags |= RXRPC_LAST_PACKET;
else if (call->tx_top - call->acks_hard_ack <
call->tx_winsize)
- txb->wire.flags |= RXRPC_MORE_PACKETS;
+ txb->flags |= RXRPC_MORE_PACKETS;

ret = call->security->secure_packet(call, txb);
if (ret < 0)
diff --git a/net/rxrpc/txbuf.c b/net/rxrpc/txbuf.c
index f2903c81cf5b..48d5a8f644e5 100644
--- a/net/rxrpc/txbuf.c
+++ b/net/rxrpc/txbuf.c
@@ -31,7 +31,7 @@ struct rxrpc_txbuf *rxrpc_alloc_txbuf(struct rxrpc_call *call, u8 packet_type,
txb->space = sizeof(txb->data);
txb->len = 0;
txb->offset = 0;
- txb->flags = 0;
+ txb->flags = call->conn->out_clientflag;
txb->ack_why = 0;
txb->seq = call->tx_prepared + 1;
txb->serial = 0;
@@ -40,7 +40,7 @@ struct rxrpc_txbuf *rxrpc_alloc_txbuf(struct rxrpc_call *call, u8 packet_type,
txb->wire.callNumber = htonl(call->call_id);
txb->wire.seq = htonl(txb->seq);
txb->wire.type = packet_type;
- txb->wire.flags = call->conn->out_clientflag;
+ txb->wire.flags = 0;
txb->wire.userStatus = 0;
txb->wire.securityIndex = call->security_ix;
txb->wire._rsvd = 0;