[PATCH v2 net 1/3] tcp: introduce tcp_rto_delta_us() helper for xmit timer fix
flat view
STALE3361d
REVIEWED: 1 (0M)
From: Neal Cardwell <ncardwell@google.com>
Date: 2017-08-03 13:20:13
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
Revision v2 of 2 in this series; 1 review trailer.
Revisions (2)
- v1 [diff vs current]
- v2 current
Pure refactor. This helper will be required in the xmit timer fix
later in the patch series. (Because the TLP logic will want to make
this calculation.)
Fixes: 6ba8a3b19e76 ("tcp: Tail loss probe (TLP)")
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <redacted>
Signed-off-by: Nandita Dukkipati <redacted>
Acked-by: Eric Dumazet <redacted>
---
include/net/tcp.h | 10 ++++++++++
net/ipv4/tcp_input.c | 5 +----
2 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 70483296157f..ada65e767b28 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h@@ -1916,6 +1916,16 @@ extern void tcp_rack_advance(struct tcp_sock *tp, u8 sacked, u32 end_seq, u64 xmit_time); extern void tcp_rack_reo_timeout(struct sock *sk); +/* At how many usecs into the future should the RTO fire? */ +static inline s64 tcp_rto_delta_us(const struct sock *sk) +{ + const struct sk_buff *skb = tcp_write_queue_head(sk); + u32 rto = inet_csk(sk)->icsk_rto; + u64 rto_time_stamp_us = skb->skb_mstamp + jiffies_to_usecs(rto); + + return rto_time_stamp_us - tcp_sk(sk)->tcp_mstamp; +} + /* * Save and compile IPv4 options, return a pointer to it */
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index dad026fcfd09..b9ba8d55d8b8 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c@@ -3004,10 +3004,7 @@ void tcp_rearm_rto(struct sock *sk) /* Offset the time elapsed after installing regular RTO */ if (icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { - struct sk_buff *skb = tcp_write_queue_head(sk); - u64 rto_time_stamp = skb->skb_mstamp + - jiffies_to_usecs(rto); - s64 delta_us = rto_time_stamp - tp->tcp_mstamp; + s64 delta_us = tcp_rto_delta_us(sk); /* delta_us may not be positive if the socket is locked * when the retrans timer fires and is rescheduled. */
--
2.14.0.rc1.383.gd1ce394fe2-goog