rxrpc: Only transmit one ACK per jumbo packet received

[ Upstream commit 012b7206918dcc5a4dcf1432b3e643114c95957e ]

Only generate one ACK packet for all the subpackets in a jumbo packet.  If
we would like to generate more than one ACK, we prioritise them base on
their reason code, in the order, highest first:

   OutOfSeq > NoSpace > ExceedsWin > Duplicate > Requested > Delay > Idle

For the first four, we reference the lowest offending subpacket; for the
last three, the highest.

This reduces the number of ACKs we end up transmitting to one per UDP
packet transmitted to reduce network loading and packet parsing.

Fixes: 5d7edbc923 ("rxrpc: Get rid of the Rx ring")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Reviewed-by: Jeffrey Altman <jaltman@auristor.com <mailto:jaltman@auristor.com>>
Link: https://lore.kernel.org/r/20240503150749.1001323-3-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
David Howells 2024-05-03 16:07:40 +01:00 committed by Greg Kroah-Hartman
parent fa6dbe25e2
commit 1721afe2ad
1 changed files with 35 additions and 11 deletions

View File

@ -9,6 +9,17 @@
#include "ar-internal.h" #include "ar-internal.h"
/* Override priority when generating ACKs for received DATA */
static const u8 rxrpc_ack_priority[RXRPC_ACK__INVALID] = {
[RXRPC_ACK_IDLE] = 1,
[RXRPC_ACK_DELAY] = 2,
[RXRPC_ACK_REQUESTED] = 3,
[RXRPC_ACK_DUPLICATE] = 4,
[RXRPC_ACK_EXCEEDS_WINDOW] = 5,
[RXRPC_ACK_NOSPACE] = 6,
[RXRPC_ACK_OUT_OF_SEQUENCE] = 7,
};
static void rxrpc_proto_abort(struct rxrpc_call *call, rxrpc_seq_t seq, static void rxrpc_proto_abort(struct rxrpc_call *call, rxrpc_seq_t seq,
enum rxrpc_abort_reason why) enum rxrpc_abort_reason why)
{ {
@ -366,7 +377,7 @@ static void rxrpc_input_queue_data(struct rxrpc_call *call, struct sk_buff *skb,
* Process a DATA packet. * Process a DATA packet.
*/ */
static void rxrpc_input_data_one(struct rxrpc_call *call, struct sk_buff *skb, static void rxrpc_input_data_one(struct rxrpc_call *call, struct sk_buff *skb,
bool *_notify) bool *_notify, rxrpc_serial_t *_ack_serial, int *_ack_reason)
{ {
struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
struct sk_buff *oos; struct sk_buff *oos;
@ -419,8 +430,6 @@ static void rxrpc_input_data_one(struct rxrpc_call *call, struct sk_buff *skb,
/* Send an immediate ACK if we fill in a hole */ /* Send an immediate ACK if we fill in a hole */
else if (!skb_queue_empty(&call->rx_oos_queue)) else if (!skb_queue_empty(&call->rx_oos_queue))
ack_reason = RXRPC_ACK_DELAY; ack_reason = RXRPC_ACK_DELAY;
else
call->ackr_nr_unacked++;
window++; window++;
if (after(window, wtop)) { if (after(window, wtop)) {
@ -498,12 +507,16 @@ static void rxrpc_input_data_one(struct rxrpc_call *call, struct sk_buff *skb,
} }
send_ack: send_ack:
if (ack_reason >= 0) if (ack_reason >= 0) {
rxrpc_send_ACK(call, ack_reason, serial, if (rxrpc_ack_priority[ack_reason] > rxrpc_ack_priority[*_ack_reason]) {
rxrpc_propose_ack_input_data); *_ack_serial = serial;
else *_ack_reason = ack_reason;
rxrpc_propose_delay_ACK(call, serial, } else if (rxrpc_ack_priority[ack_reason] == rxrpc_ack_priority[*_ack_reason] &&
rxrpc_propose_ack_input_data); ack_reason == RXRPC_ACK_REQUESTED) {
*_ack_serial = serial;
*_ack_reason = ack_reason;
}
}
} }
/* /*
@ -514,9 +527,11 @@ static bool rxrpc_input_split_jumbo(struct rxrpc_call *call, struct sk_buff *skb
struct rxrpc_jumbo_header jhdr; struct rxrpc_jumbo_header jhdr;
struct rxrpc_skb_priv *sp = rxrpc_skb(skb), *jsp; struct rxrpc_skb_priv *sp = rxrpc_skb(skb), *jsp;
struct sk_buff *jskb; struct sk_buff *jskb;
rxrpc_serial_t ack_serial = 0;
unsigned int offset = sizeof(struct rxrpc_wire_header); unsigned int offset = sizeof(struct rxrpc_wire_header);
unsigned int len = skb->len - offset; unsigned int len = skb->len - offset;
bool notify = false; bool notify = false;
int ack_reason = 0;
while (sp->hdr.flags & RXRPC_JUMBO_PACKET) { while (sp->hdr.flags & RXRPC_JUMBO_PACKET) {
if (len < RXRPC_JUMBO_SUBPKTLEN) if (len < RXRPC_JUMBO_SUBPKTLEN)
@ -536,7 +551,7 @@ static bool rxrpc_input_split_jumbo(struct rxrpc_call *call, struct sk_buff *skb
jsp = rxrpc_skb(jskb); jsp = rxrpc_skb(jskb);
jsp->offset = offset; jsp->offset = offset;
jsp->len = RXRPC_JUMBO_DATALEN; jsp->len = RXRPC_JUMBO_DATALEN;
rxrpc_input_data_one(call, jskb, &notify); rxrpc_input_data_one(call, jskb, &notify, &ack_serial, &ack_reason);
rxrpc_free_skb(jskb, rxrpc_skb_put_jumbo_subpacket); rxrpc_free_skb(jskb, rxrpc_skb_put_jumbo_subpacket);
sp->hdr.flags = jhdr.flags; sp->hdr.flags = jhdr.flags;
@ -549,7 +564,16 @@ static bool rxrpc_input_split_jumbo(struct rxrpc_call *call, struct sk_buff *skb
sp->offset = offset; sp->offset = offset;
sp->len = len; sp->len = len;
rxrpc_input_data_one(call, skb, &notify); rxrpc_input_data_one(call, skb, &notify, &ack_serial, &ack_reason);
if (ack_reason > 0) {
rxrpc_send_ACK(call, ack_reason, ack_serial,
rxrpc_propose_ack_input_data);
} else {
call->ackr_nr_unacked++;
rxrpc_propose_delay_ACK(call, sp->hdr.serial,
rxrpc_propose_ack_input_data);
}
if (notify) { if (notify) {
trace_rxrpc_notify_socket(call->debug_id, sp->hdr.serial); trace_rxrpc_notify_socket(call->debug_id, sp->hdr.serial);
rxrpc_notify_socket(call); rxrpc_notify_socket(call);