From f07373ead455a396e15a431bc08d8ce1dac6f1cf Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 22 Sep 2016 00:29:32 +0100 Subject: [PATCH] rxrpc: Add re-sent Tx annotation Add a Tx-phase annotation for packet buffers to indicate that a buffer has already been retransmitted. This will be used by future congestion management. Re-retransmissions of a packet don't affect the congestion window managment in the same way as initial retransmissions. Signed-off-by: David Howells --- net/rxrpc/ar-internal.h | 2 ++ net/rxrpc/call_event.c | 28 +++++++++++++++++++--------- net/rxrpc/input.c | 14 +++++++++++--- 3 files changed, 32 insertions(+), 12 deletions(-) diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index f021df4..dcf54e3 100644 --- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -505,6 +505,8 @@ struct rxrpc_call { #define RXRPC_TX_ANNO_UNACK 1 #define RXRPC_TX_ANNO_NAK 2 #define RXRPC_TX_ANNO_RETRANS 3 +#define RXRPC_TX_ANNO_MASK 0x03 +#define RXRPC_TX_ANNO_RESENT 0x04 #define RXRPC_RX_ANNO_JUMBO 0x3f /* Jumbo subpacket number + 1 if not zero */ #define RXRPC_RX_ANNO_JLAST 0x40 /* Set if last element of a jumbo packet */ #define RXRPC_RX_ANNO_VERIFIED 0x80 /* Set if verified and decrypted */ diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c index 6247ce2..34ad967 100644 --- a/net/rxrpc/call_event.c +++ b/net/rxrpc/call_event.c @@ -144,7 +144,7 @@ static void rxrpc_resend(struct rxrpc_call *call) rxrpc_seq_t cursor, seq, top; unsigned long resend_at, now; int ix; - u8 annotation; + u8 annotation, anno_type; _enter("{%d,%d}", call->tx_hard_ack, call->tx_top); @@ -165,14 +165,16 @@ static void rxrpc_resend(struct rxrpc_call *call) for (seq = cursor + 1; before_eq(seq, top); seq++) { ix = seq & RXRPC_RXTX_BUFF_MASK; annotation = call->rxtx_annotations[ix]; - if (annotation == RXRPC_TX_ANNO_ACK) + anno_type = annotation & RXRPC_TX_ANNO_MASK; + annotation &= ~RXRPC_TX_ANNO_MASK; + if (anno_type == RXRPC_TX_ANNO_ACK) continue; skb = call->rxtx_buffer[ix]; rxrpc_see_skb(skb, rxrpc_skb_tx_seen); sp = rxrpc_skb(skb); - if (annotation == RXRPC_TX_ANNO_UNACK) { + if (anno_type == RXRPC_TX_ANNO_UNACK) { if (time_after(sp->resend_at, now)) { if (time_before(sp->resend_at, resend_at)) resend_at = sp->resend_at; @@ -181,7 +183,7 @@ static void rxrpc_resend(struct rxrpc_call *call) } /* Okay, we need to retransmit a packet. */ - call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS; + call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS | annotation; } call->resend_at = resend_at; @@ -194,7 +196,8 @@ static void rxrpc_resend(struct rxrpc_call *call) for (seq = cursor + 1; before_eq(seq, top); seq++) { ix = seq & RXRPC_RXTX_BUFF_MASK; annotation = call->rxtx_annotations[ix]; - if (annotation != RXRPC_TX_ANNO_RETRANS) + anno_type = annotation & RXRPC_TX_ANNO_MASK; + if (anno_type != RXRPC_TX_ANNO_RETRANS) continue; skb = call->rxtx_buffer[ix]; @@ -220,10 +223,17 @@ static void rxrpc_resend(struct rxrpc_call *call) * received and the packet might have been hard-ACK'd (in which * case it will no longer be in the buffer). */ - if (after(seq, call->tx_hard_ack) && - (call->rxtx_annotations[ix] == RXRPC_TX_ANNO_RETRANS || - call->rxtx_annotations[ix] == RXRPC_TX_ANNO_NAK)) - call->rxtx_annotations[ix] = RXRPC_TX_ANNO_UNACK; + if (after(seq, call->tx_hard_ack)) { + annotation = call->rxtx_annotations[ix]; + anno_type = annotation & RXRPC_TX_ANNO_MASK; + if (anno_type == RXRPC_TX_ANNO_RETRANS || + anno_type == RXRPC_TX_ANNO_NAK) { + annotation &= ~RXRPC_TX_ANNO_MASK; + annotation |= RXRPC_TX_ANNO_UNACK; + } + annotation |= RXRPC_TX_ANNO_RESENT; + call->rxtx_annotations[ix] = annotation; + } if (after(call->tx_hard_ack, seq)) seq = call->tx_hard_ack; diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c index 7ac1edf..aa261df 100644 --- a/net/rxrpc/input.c +++ b/net/rxrpc/input.c @@ -388,17 +388,25 @@ static void rxrpc_input_soft_acks(struct rxrpc_call *call, u8 *acks, { bool resend = false; int ix; + u8 annotation, anno_type; for (; nr_acks > 0; nr_acks--, seq++) { ix = seq & RXRPC_RXTX_BUFF_MASK; + annotation = call->rxtx_annotations[ix]; + anno_type = annotation & RXRPC_TX_ANNO_MASK; + annotation &= ~RXRPC_TX_ANNO_MASK; switch (*acks++) { case RXRPC_ACK_TYPE_ACK: - call->rxtx_annotations[ix] = RXRPC_TX_ANNO_ACK; + if (anno_type == RXRPC_TX_ANNO_ACK) + continue; + call->rxtx_annotations[ix] = + RXRPC_TX_ANNO_ACK | annotation; break; case RXRPC_ACK_TYPE_NACK: - if (call->rxtx_annotations[ix] == RXRPC_TX_ANNO_NAK) + if (anno_type == RXRPC_TX_ANNO_NAK) continue; - call->rxtx_annotations[ix] = RXRPC_TX_ANNO_NAK; + call->rxtx_annotations[ix] = + RXRPC_TX_ANNO_NAK | annotation; resend = true; break; default: -- 2.7.4