* [PATCH net 1/4] rxrpc: Fix generation of serial numbers to skip zero
2024-02-02 15:19 [PATCH net 0/4] rxrpc: Miscellaneous fixes David Howells
@ 2024-02-02 15:19 ` David Howells
2024-02-02 15:19 ` [PATCH net 2/4] rxrpc: Fix delayed ACKs to not set the reference serial number David Howells
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: David Howells @ 2024-02-02 15:19 UTC (permalink / raw)
To: netdev
Cc: David Howells, Marc Dionne, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni, linux-afs, linux-kernel
In the Rx protocol, every packet generated is marked with a per-connection
monotonically increasing serial number. This number can be referenced in
an ACK packet generated in response to an incoming packet - thereby
allowing the sender to use this for RTT determination, amongst other
things.
However, if the reference field in the ACK is zero, it doesn't refer to any
incoming packet (it could be a ping to find out if a packet got lost, for
example) - so we shouldn't generate zero serial numbers.
Fix the generation of serial numbers to retry if it comes up with a zero.
Furthermore, since the serial numbers are only ever allocated within the
I/O thread this connection is bound to, there's no need for atomics so
remove that too.
Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
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
---
net/rxrpc/ar-internal.h | 16 +++++++++++++++-
net/rxrpc/conn_event.c | 2 +-
net/rxrpc/output.c | 8 ++++----
net/rxrpc/proc.c | 2 +-
net/rxrpc/rxkad.c | 4 ++--
5 files changed, 23 insertions(+), 9 deletions(-)
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index dbeb75c29857..31b0dd8c9b2d 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -510,7 +510,7 @@ struct rxrpc_connection {
enum rxrpc_call_completion completion; /* Completion condition */
s32 abort_code; /* Abort code of connection abort */
int debug_id; /* debug ID for printks */
- atomic_t serial; /* packet serial number counter */
+ rxrpc_serial_t tx_serial; /* Outgoing packet serial number counter */
unsigned int hi_serial; /* highest serial number received */
u32 service_id; /* Service ID, possibly upgraded */
u32 security_level; /* Security level selected */
@@ -822,6 +822,20 @@ static inline bool rxrpc_sending_to_client(const struct rxrpc_txbuf *txb)
#include <trace/events/rxrpc.h>
+/*
+ * Allocate the next serial number on a connection. 0 must be skipped.
+ */
+static inline rxrpc_serial_t rxrpc_get_next_serial(struct rxrpc_connection *conn)
+{
+ rxrpc_serial_t serial;
+
+ serial = conn->tx_serial;
+ if (serial == 0)
+ serial = 1;
+ conn->tx_serial = serial + 1;
+ return serial;
+}
+
/*
* af_rxrpc.c
*/
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 95f4bc206b3d..ec5eae60ab0c 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -117,7 +117,7 @@ void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
iov[2].iov_base = &ack_info;
iov[2].iov_len = sizeof(ack_info);
- serial = atomic_inc_return(&conn->serial);
+ serial = rxrpc_get_next_serial(conn);
pkt.whdr.epoch = htonl(conn->proto.epoch);
pkt.whdr.cid = htonl(conn->proto.cid | channel);
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index a0906145e829..4a292f860ae3 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -216,7 +216,7 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
iov[0].iov_len = sizeof(txb->wire) + sizeof(txb->ack) + n;
len = iov[0].iov_len;
- serial = atomic_inc_return(&conn->serial);
+ serial = rxrpc_get_next_serial(conn);
txb->wire.serial = htonl(serial);
trace_rxrpc_tx_ack(call->debug_id, serial,
ntohl(txb->ack.firstPacket),
@@ -302,7 +302,7 @@ int rxrpc_send_abort_packet(struct rxrpc_call *call)
iov[0].iov_base = &pkt;
iov[0].iov_len = sizeof(pkt);
- serial = atomic_inc_return(&conn->serial);
+ serial = rxrpc_get_next_serial(conn);
pkt.whdr.serial = htonl(serial);
iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, sizeof(pkt));
@@ -334,7 +334,7 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
_enter("%x,{%d}", txb->seq, txb->len);
/* Each transmission of a Tx packet needs a new serial number */
- serial = atomic_inc_return(&conn->serial);
+ serial = rxrpc_get_next_serial(conn);
txb->wire.serial = htonl(serial);
if (test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) &&
@@ -558,7 +558,7 @@ void rxrpc_send_conn_abort(struct rxrpc_connection *conn)
len = iov[0].iov_len + iov[1].iov_len;
- serial = atomic_inc_return(&conn->serial);
+ serial = rxrpc_get_next_serial(conn);
whdr.serial = htonl(serial);
iov_iter_kvec(&msg.msg_iter, WRITE, iov, 2, len);
diff --git a/net/rxrpc/proc.c b/net/rxrpc/proc.c
index 6c86cbb98d1d..26dc2f26d92d 100644
--- a/net/rxrpc/proc.c
+++ b/net/rxrpc/proc.c
@@ -181,7 +181,7 @@ static int rxrpc_connection_seq_show(struct seq_file *seq, void *v)
atomic_read(&conn->active),
state,
key_serial(conn->key),
- atomic_read(&conn->serial),
+ conn->tx_serial,
conn->hi_serial,
conn->channels[0].call_id,
conn->channels[1].call_id,
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index b52dedcebce0..6b32d61d4cdc 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -664,7 +664,7 @@ static int rxkad_issue_challenge(struct rxrpc_connection *conn)
len = iov[0].iov_len + iov[1].iov_len;
- serial = atomic_inc_return(&conn->serial);
+ serial = rxrpc_get_next_serial(conn);
whdr.serial = htonl(serial);
ret = kernel_sendmsg(conn->local->socket, &msg, iov, 2, len);
@@ -721,7 +721,7 @@ static int rxkad_send_response(struct rxrpc_connection *conn,
len = iov[0].iov_len + iov[1].iov_len + iov[2].iov_len;
- serial = atomic_inc_return(&conn->serial);
+ serial = rxrpc_get_next_serial(conn);
whdr.serial = htonl(serial);
rxrpc_local_dont_fragment(conn->local, false);
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH net 2/4] rxrpc: Fix delayed ACKs to not set the reference serial number
2024-02-02 15:19 [PATCH net 0/4] rxrpc: Miscellaneous fixes David Howells
2024-02-02 15:19 ` [PATCH net 1/4] rxrpc: Fix generation of serial numbers to skip zero David Howells
@ 2024-02-02 15:19 ` David Howells
2024-02-02 15:19 ` [PATCH net 3/4] rxrpc: Fix response to PING RESPONSE ACKs to a dead call David Howells
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: David Howells @ 2024-02-02 15:19 UTC (permalink / raw)
To: netdev
Cc: David Howells, Marc Dionne, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni, linux-afs, linux-kernel
Fix the construction of delayed ACKs to not set the reference serial number
as they can't be used as an RTT reference.
Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
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
---
net/rxrpc/ar-internal.h | 1 -
net/rxrpc/call_event.c | 6 +-----
2 files changed, 1 insertion(+), 6 deletions(-)
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 31b0dd8c9b2d..b4ab26c3718a 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -696,7 +696,6 @@ struct rxrpc_call {
/* Receive-phase ACK management (ACKs we send). */
u8 ackr_reason; /* reason to ACK */
u16 ackr_sack_base; /* Starting slot in SACK table ring */
- rxrpc_serial_t ackr_serial; /* serial of packet being ACK'd */
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 */
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index e363f21a2014..c61efe08695d 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -43,8 +43,6 @@ void rxrpc_propose_delay_ACK(struct rxrpc_call *call, rxrpc_serial_t serial,
unsigned long expiry = rxrpc_soft_ack_delay;
unsigned long now = jiffies, ack_at;
- call->ackr_serial = serial;
-
if (rxrpc_soft_ack_delay < expiry)
expiry = rxrpc_soft_ack_delay;
if (call->peer->srtt_us != 0)
@@ -373,7 +371,6 @@ static void rxrpc_send_initial_ping(struct rxrpc_call *call)
bool rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb)
{
unsigned long now, next, t;
- rxrpc_serial_t ackr_serial;
bool resend = false, expired = false;
s32 abort_code;
@@ -423,8 +420,7 @@ bool rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb)
if (time_after_eq(now, t)) {
trace_rxrpc_timer(call, rxrpc_timer_exp_ack, now);
cmpxchg(&call->delay_ack_at, t, now + MAX_JIFFY_OFFSET);
- ackr_serial = xchg(&call->ackr_serial, 0);
- rxrpc_send_ACK(call, RXRPC_ACK_DELAY, ackr_serial,
+ rxrpc_send_ACK(call, RXRPC_ACK_DELAY, 0,
rxrpc_propose_ack_ping_for_lost_ack);
}
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH net 4/4] rxrpc: Fix counting of new acks and nacks
2024-02-02 15:19 [PATCH net 0/4] rxrpc: Miscellaneous fixes David Howells
` (2 preceding siblings ...)
2024-02-02 15:19 ` [PATCH net 3/4] rxrpc: Fix response to PING RESPONSE ACKs to a dead call David Howells
@ 2024-02-02 15:19 ` David Howells
2024-02-05 12:40 ` [PATCH net 0/4] rxrpc: Miscellaneous fixes patchwork-bot+netdevbpf
4 siblings, 0 replies; 6+ messages in thread
From: David Howells @ 2024-02-02 15:19 UTC (permalink / raw)
To: netdev
Cc: David Howells, Marc Dionne, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni, linux-afs, linux-kernel
Fix the counting of new acks and nacks when parsing a packet - something
that is used in congestion control.
As the code stands, it merely notes if there are any nacks whereas what we
really should do is compare the previous SACK table to the new one,
assuming we get two successive ACK packets with nacks in them. However, we
really don't want to do that if we can avoid it as the tables might not
correspond directly as one may be shifted from the other - something that
will only get harder to deal with once extended ACK tables come into full
use (with a capacity of up to 8192).
Instead, count the number of nacks shifted out of the old SACK, the number
of nacks retained in the portion still active and the number of new acks
and nacks in the new table then calculate what we need.
Note this ends up a bit of an estimate as the Rx protocol allows acks to be
withdrawn by the receiver and packets requested to be retransmitted.
Fixes: d57a3a151660 ("rxrpc: Save last ACK's SACK table rather than marking txbufs")
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 | 8 ++-
net/rxrpc/ar-internal.h | 20 ++++--
net/rxrpc/call_event.c | 6 +-
net/rxrpc/call_object.c | 1 +
net/rxrpc/input.c | 115 +++++++++++++++++++++++++++++------
5 files changed, 122 insertions(+), 28 deletions(-)
diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 4c1ef7b3705c..87b8de9b6c1c 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -128,6 +128,7 @@
EM(rxrpc_skb_eaten_by_unshare_nomem, "ETN unshar-nm") \
EM(rxrpc_skb_get_conn_secured, "GET conn-secd") \
EM(rxrpc_skb_get_conn_work, "GET conn-work") \
+ EM(rxrpc_skb_get_last_nack, "GET last-nack") \
EM(rxrpc_skb_get_local_work, "GET locl-work") \
EM(rxrpc_skb_get_reject_work, "GET rej-work ") \
EM(rxrpc_skb_get_to_recvmsg, "GET to-recv ") \
@@ -141,6 +142,7 @@
EM(rxrpc_skb_put_error_report, "PUT error-rep") \
EM(rxrpc_skb_put_input, "PUT input ") \
EM(rxrpc_skb_put_jumbo_subpacket, "PUT jumbo-sub") \
+ EM(rxrpc_skb_put_last_nack, "PUT last-nack") \
EM(rxrpc_skb_put_purge, "PUT purge ") \
EM(rxrpc_skb_put_rotate, "PUT rotate ") \
EM(rxrpc_skb_put_unknown, "PUT unknown ") \
@@ -1552,7 +1554,7 @@ TRACE_EVENT(rxrpc_congest,
memcpy(&__entry->sum, summary, sizeof(__entry->sum));
),
- TP_printk("c=%08x r=%08x %s q=%08x %s cw=%u ss=%u nA=%u,%u+%u r=%u b=%u u=%u d=%u l=%x%s%s%s",
+ TP_printk("c=%08x r=%08x %s q=%08x %s cw=%u ss=%u nA=%u,%u+%u,%u b=%u u=%u d=%u l=%x%s%s%s",
__entry->call,
__entry->ack_serial,
__print_symbolic(__entry->sum.ack_reason, rxrpc_ack_names),
@@ -1560,9 +1562,9 @@ TRACE_EVENT(rxrpc_congest,
__print_symbolic(__entry->sum.mode, rxrpc_congest_modes),
__entry->sum.cwnd,
__entry->sum.ssthresh,
- __entry->sum.nr_acks, __entry->sum.saw_nacks,
+ __entry->sum.nr_acks, __entry->sum.nr_retained_nacks,
__entry->sum.nr_new_acks,
- __entry->sum.nr_rot_new_acks,
+ __entry->sum.nr_new_nacks,
__entry->top - __entry->hard_ack,
__entry->sum.cumulative_acks,
__entry->sum.dup_acks,
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index b4ab26c3718a..7818aae1be8e 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -199,11 +199,19 @@ struct rxrpc_host_header {
*/
struct rxrpc_skb_priv {
struct rxrpc_connection *conn; /* Connection referred to (poke packet) */
- u16 offset; /* Offset of data */
- u16 len; /* Length of data */
- u8 flags;
+ union {
+ struct {
+ u16 offset; /* Offset of data */
+ u16 len; /* Length of data */
+ u8 flags;
#define RXRPC_RX_VERIFIED 0x01
-
+ };
+ struct {
+ rxrpc_seq_t first_ack; /* First packet in acks table */
+ u8 nr_acks; /* Number of acks+nacks */
+ u8 nr_nacks; /* Number of nacks */
+ };
+ };
struct rxrpc_host_header hdr; /* RxRPC packet header from this packet */
};
@@ -692,6 +700,7 @@ struct rxrpc_call {
u8 cong_dup_acks; /* Count of ACKs showing missing packets */
u8 cong_cumul_acks; /* Cumulative ACK count */
ktime_t cong_tstamp; /* Last time cwnd was changed */
+ struct sk_buff *cong_last_nack; /* Last ACK with nacks received */
/* Receive-phase ACK management (ACKs we send). */
u8 ackr_reason; /* reason to ACK */
@@ -729,7 +738,8 @@ struct rxrpc_call {
struct rxrpc_ack_summary {
u16 nr_acks; /* Number of ACKs in packet */
u16 nr_new_acks; /* Number of new ACKs in packet */
- u16 nr_rot_new_acks; /* Number of rotated new ACKs */
+ u16 nr_new_nacks; /* Number of new nacks in packet */
+ u16 nr_retained_nacks; /* Number of nacks retained between ACKs */
u8 ack_reason;
bool saw_nacks; /* Saw NACKs in packet */
bool new_low_nack; /* T if new low NACK found */
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index c61efe08695d..0f78544d043b 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -112,6 +112,7 @@ static void rxrpc_congestion_timeout(struct rxrpc_call *call)
void rxrpc_resend(struct rxrpc_call *call, struct sk_buff *ack_skb)
{
struct rxrpc_ackpacket *ack = NULL;
+ struct rxrpc_skb_priv *sp;
struct rxrpc_txbuf *txb;
unsigned long resend_at;
rxrpc_seq_t transmitted = READ_ONCE(call->tx_transmitted);
@@ -139,14 +140,15 @@ void rxrpc_resend(struct rxrpc_call *call, struct sk_buff *ack_skb)
* explicitly NAK'd packets.
*/
if (ack_skb) {
+ sp = rxrpc_skb(ack_skb);
ack = (void *)ack_skb->data + sizeof(struct rxrpc_wire_header);
- for (i = 0; i < ack->nAcks; i++) {
+ for (i = 0; i < sp->nr_acks; i++) {
rxrpc_seq_t seq;
if (ack->acks[i] & 1)
continue;
- seq = ntohl(ack->firstPacket) + i;
+ seq = sp->first_ack + i;
if (after(txb->seq, transmitted))
break;
if (after(txb->seq, seq))
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 0943e54370ba..9fc9a6c3f685 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -686,6 +686,7 @@ static void rxrpc_destroy_call(struct work_struct *work)
del_timer_sync(&call->timer);
+ rxrpc_free_skb(call->cong_last_nack, rxrpc_skb_put_last_nack);
rxrpc_cleanup_ring(call);
while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
struct rxrpc_txbuf, call_link))) {
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 92495e73b869..9691de00ade7 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -45,11 +45,9 @@ static void rxrpc_congestion_management(struct rxrpc_call *call,
}
cumulative_acks += summary->nr_new_acks;
- cumulative_acks += summary->nr_rot_new_acks;
if (cumulative_acks > 255)
cumulative_acks = 255;
- summary->mode = call->cong_mode;
summary->cwnd = call->cong_cwnd;
summary->ssthresh = call->cong_ssthresh;
summary->cumulative_acks = cumulative_acks;
@@ -151,6 +149,7 @@ static void rxrpc_congestion_management(struct rxrpc_call *call,
cwnd = RXRPC_TX_MAX_WINDOW;
call->cong_cwnd = cwnd;
call->cong_cumul_acks = cumulative_acks;
+ summary->mode = call->cong_mode;
trace_rxrpc_congest(call, summary, acked_serial, change);
if (resend)
rxrpc_resend(call, skb);
@@ -213,7 +212,6 @@ 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;
- summary->nr_rot_new_acks++;
if (test_bit(RXRPC_TXBUF_LAST, &txb->flags)) {
set_bit(RXRPC_CALL_TX_LAST, &call->flags);
rot_last = true;
@@ -254,6 +252,11 @@ static void rxrpc_end_tx_phase(struct rxrpc_call *call, bool reply_begun,
{
ASSERT(test_bit(RXRPC_CALL_TX_LAST, &call->flags));
+ if (unlikely(call->cong_last_nack)) {
+ rxrpc_free_skb(call->cong_last_nack, rxrpc_skb_put_last_nack);
+ call->cong_last_nack = NULL;
+ }
+
switch (__rxrpc_call_state(call)) {
case RXRPC_CALL_CLIENT_SEND_REQUEST:
case RXRPC_CALL_CLIENT_AWAIT_REPLY:
@@ -702,6 +705,43 @@ static void rxrpc_input_ackinfo(struct rxrpc_call *call, struct sk_buff *skb,
wake_up(&call->waitq);
}
+/*
+ * Determine how many nacks from the previous ACK have now been satisfied.
+ */
+static rxrpc_seq_t rxrpc_input_check_prev_ack(struct rxrpc_call *call,
+ struct rxrpc_ack_summary *summary,
+ rxrpc_seq_t seq)
+{
+ struct sk_buff *skb = call->cong_last_nack;
+ struct rxrpc_ackpacket ack;
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+ unsigned int i, new_acks = 0, retained_nacks = 0;
+ rxrpc_seq_t old_seq = sp->first_ack;
+ u8 *acks = skb->data + sizeof(struct rxrpc_wire_header) + sizeof(ack);
+
+ if (after_eq(seq, old_seq + sp->nr_acks)) {
+ summary->nr_new_acks += sp->nr_nacks;
+ summary->nr_new_acks += seq - (old_seq + sp->nr_acks);
+ summary->nr_retained_nacks = 0;
+ } else if (seq == old_seq) {
+ summary->nr_retained_nacks = sp->nr_nacks;
+ } else {
+ for (i = 0; i < sp->nr_acks; i++) {
+ if (acks[i] == RXRPC_ACK_TYPE_NACK) {
+ if (before(old_seq + i, seq))
+ new_acks++;
+ else
+ retained_nacks++;
+ }
+ }
+
+ summary->nr_new_acks += new_acks;
+ summary->nr_retained_nacks = retained_nacks;
+ }
+
+ return old_seq + sp->nr_acks;
+}
+
/*
* Process individual soft ACKs.
*
@@ -711,25 +751,51 @@ static void rxrpc_input_ackinfo(struct rxrpc_call *call, struct sk_buff *skb,
* the timer on the basis that the peer might just not have processed them at
* the time the ACK was sent.
*/
-static void rxrpc_input_soft_acks(struct rxrpc_call *call, u8 *acks,
- rxrpc_seq_t seq, int nr_acks,
- struct rxrpc_ack_summary *summary)
+static void rxrpc_input_soft_acks(struct rxrpc_call *call,
+ struct rxrpc_ack_summary *summary,
+ struct sk_buff *skb,
+ rxrpc_seq_t seq,
+ rxrpc_seq_t since)
{
- unsigned int i;
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+ unsigned int i, old_nacks = 0;
+ rxrpc_seq_t lowest_nak = seq + sp->nr_acks;
+ u8 *acks = skb->data + sizeof(struct rxrpc_wire_header) + sizeof(struct rxrpc_ackpacket);
- for (i = 0; i < nr_acks; i++) {
+ for (i = 0; i < sp->nr_acks; i++) {
if (acks[i] == RXRPC_ACK_TYPE_ACK) {
summary->nr_acks++;
- summary->nr_new_acks++;
+ if (after_eq(seq, since))
+ summary->nr_new_acks++;
} else {
- if (!summary->saw_nacks &&
- call->acks_lowest_nak != seq + i) {
- call->acks_lowest_nak = seq + i;
- summary->new_low_nack = true;
- }
summary->saw_nacks = true;
+ if (before(seq, since)) {
+ /* Overlap with previous ACK */
+ old_nacks++;
+ } else {
+ summary->nr_new_nacks++;
+ sp->nr_nacks++;
+ }
+
+ if (before(seq, lowest_nak))
+ lowest_nak = seq;
}
+ seq++;
+ }
+
+ if (lowest_nak != call->acks_lowest_nak) {
+ call->acks_lowest_nak = lowest_nak;
+ summary->new_low_nack = true;
}
+
+ /* We *can* have more nacks than we did - the peer is permitted to drop
+ * packets it has soft-acked and re-request them. Further, it is
+ * possible for the nack distribution to change whilst the number of
+ * nacks stays the same or goes down.
+ */
+ if (old_nacks < summary->nr_retained_nacks)
+ summary->nr_new_acks += summary->nr_retained_nacks - old_nacks;
+ summary->nr_retained_nacks = old_nacks;
}
/*
@@ -773,7 +839,7 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
struct rxrpc_ackinfo info;
rxrpc_serial_t ack_serial, acked_serial;
- rxrpc_seq_t first_soft_ack, hard_ack, prev_pkt;
+ rxrpc_seq_t first_soft_ack, hard_ack, prev_pkt, since;
int nr_acks, offset, ioffset;
_enter("");
@@ -789,6 +855,8 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
prev_pkt = ntohl(ack.previousPacket);
hard_ack = first_soft_ack - 1;
nr_acks = ack.nAcks;
+ sp->first_ack = first_soft_ack;
+ sp->nr_acks = nr_acks;
summary.ack_reason = (ack.reason < RXRPC_ACK__INVALID ?
ack.reason : RXRPC_ACK__INVALID);
@@ -858,6 +926,16 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
if (nr_acks > 0)
skb_condense(skb);
+ if (call->cong_last_nack) {
+ since = rxrpc_input_check_prev_ack(call, &summary, first_soft_ack);
+ rxrpc_free_skb(call->cong_last_nack, rxrpc_skb_put_last_nack);
+ call->cong_last_nack = NULL;
+ } else {
+ summary.nr_new_acks = first_soft_ack - call->acks_first_seq;
+ call->acks_lowest_nak = first_soft_ack + nr_acks;
+ since = first_soft_ack;
+ }
+
call->acks_latest_ts = skb->tstamp;
call->acks_first_seq = first_soft_ack;
call->acks_prev_seq = prev_pkt;
@@ -866,7 +944,7 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
case RXRPC_ACK_PING:
break;
default:
- if (after(acked_serial, call->acks_highest_serial))
+ if (acked_serial && after(acked_serial, call->acks_highest_serial))
call->acks_highest_serial = acked_serial;
break;
}
@@ -905,8 +983,9 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
if (nr_acks > 0) {
if (offset > (int)skb->len - nr_acks)
return rxrpc_proto_abort(call, 0, rxrpc_eproto_ackr_short_sack);
- rxrpc_input_soft_acks(call, skb->data + offset, first_soft_ack,
- nr_acks, &summary);
+ rxrpc_input_soft_acks(call, &summary, skb, first_soft_ack, since);
+ rxrpc_get_skb(skb, rxrpc_skb_get_last_nack);
+ call->cong_last_nack = skb;
}
if (test_bit(RXRPC_CALL_TX_LAST, &call->flags) &&
^ permalink raw reply related [flat|nested] 6+ messages in thread