: Simplify interface of dccp_sample_rtt
PATCH 3/6 : Simplify interface of dccp_sample_rtt
The third parameter of dccp_sample_rtt now becomes useless and is removed.
Also combined the subtraction of the timestamp echo and the elapsed time. This is safe, since (a) presence of timestamp echo is tested first and (b) elapsed time is either present and non-zero or it is not set and equals 0 due to the memset in dccp_parse_options.
To avoid measuring option-processing time, the timestamp for measuring the initial Request/Response RTT sample is taken directly when the function is called (the Linux implementation always adds a timestamp on the Request, so there is no loss in doing this).
--- net/dccp/ccids/ccid3.c | 6 +++--- net/dccp/dccp.h | 3 +-- net/dccp/input.c | 44 +++++++++++++++----------------------------- 3 files changed, 19 insertions(+), 34 deletions(-)
net/dccp/ccids/ccid3.c +3 -3
@@ -448,7 +448,7 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)* Calculate new round trip sample as per [RFC 3448, 4.3] by * R_sample = (now - t_recvdata) - t_elapsed */ - r_sample =dccp_sample_rtt (sk, now, &packet->dccphtx_tstamp); + r_sample =dccp_sample_rtt (sk,ktime_us_delta (now, packet->dccphtx_tstamp));/* * Update RTT estimate by
@@ -881,9 +881,9 @@ static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)case DCCP_PKT_DATAACK :if (opt_recv->dccpor_timestamp_echo =0 )break ; + r_sample =dccp_timestamp () - opt_recv->dccpor_timestamp_echo; rtt_prev = hcrx->ccid3hcrx_rtt; - now =ktime_get_real (); - r_sample =dccp_sample_rtt (sk, now,NULL ); + r_sample =dccp_sample_rtt (sk,10 * r_sample);if (hcrx->ccid3hcrx_state =TFRC_RSTATE_NO_DATA ) hcrx->ccid3hcrx_rtt = r_sample;
net/dccp/dccp.h +1 -2
@@ -297,8 +297,7 @@ extern int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr,extern int dccp_send_reset (struct sock *sk,enum dccp_reset_codes code);extern void dccp_send_close (struct sock *sk,const int active);extern int dccp_invalid_packet (struct sk_buff *skb); -extern u32 dccp_sample_rtt (struct sock *sk,ktime_t t_recv, -ktime_t *t_history); +extern u32 dccp_sample_rtt (struct sock *sk,long delta);static inline int dccp_bad_service_code (const struct sock *sk,const __be32 service)
net/dccp/input.c +15 -29
68 lines not on this page · raw message
Signature · 1 line
1.5.3.1
From: Arnaldo Carvalho de Melo <[email protected]>
Date: Sat, 22 Sep 2007 18:09:50 -0300
Quoted 7 lines
The third parameter of
dccp_sample_rttnow becomes useless and is removed.Also combined the subtraction of the timestamp echo and the elapsed time. This is safe, since (a) presence of timestamp echo is tested first and (b) elapsed time is either present and non-zero or it is not set and equals 0 due to the memset in
dccp_parse_options.
Quoted 8 lines
To avoid measuring option-processing time, the timestamp for measuring the initial Request/Response RTT sample is taken directly when the function is called (the Linux implementation always adds a timestamp on the Request, so there is no loss in doing this).
Signed-off-by Gerrit Renker <[email protected]>Signed-off-by Ian McDonald <[email protected]>Signed-off-by Arnaldo Carvalho de Melo <[email protected]>
Applied, thanks.