: Revert use of MSS instead of s
PATCH 1/16 : Revert use of MSS instead of s
This updates the CCID3 code with regard to two instances of using MSS' in place of s':
1. The RFC3390-based initial rate: both rfc3448bis as well as the Faster Restart draft now consistently use `s' instead of MSS.
2. Now agrees with section 4.2 of rfc3448bis: "If the sender is ready to send data when it does not yet have a round trip sample, the value of X is set to s bytes per second, for segment size s [...]"
Signed-off-by Gerrit Renker <[email protected]>
Signed-off-by Ian McDonald <[email protected]>
--- net/dccp/ccids/ccid3.c | 21 ++++++++++++--------- 1 files changed, 12 insertions(+), 9 deletions(-)
net/dccp/ccids/ccid3.c +12 -9
@@ -83,18 +83,21 @@ static void ccid3_hc_tx_set_state(struct sock *sk, }/* -* Compute the initial sending rate X_init according to RFC 3390: -* w_init = min(4 * MSS, max(2 * MSS, 4380 bytes)) -* X_init = w_init / RTT +* Compute the initial sending rate X_init in the manner of RFC 3390: +* +* X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT +* +* Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis +* (rev-02) clarifies the use of RFC 3390 with regard to the above formula. * For consistency with other parts of the code, X_init is scaled by 2^6. */ static inline u64 rfc3390_initial_rate (struct sock *sk) { -const struct dccp_sock *dp =dccp_sk (sk); -const __u32 w_init =min (4 * dp->dccps_mss_cache, -max (2 * dp->dccps_mss_cache,4380U )); +const struct ccid3_hc_tx_sock *hctx =ccid3_hc_tx_sk (sk); +const __u32 w_init =min_t (__u32,4 * hctx->ccid3hctx_s, +max_t (__u32,2 * hctx->ccid3hctx_s,4380 )); -return scaled_div (w_init <<6 ,ccid3_hc_tx_sk (sk)->ccid3hctx_rtt); +return scaled_div (w_init <<6 , hctx->ccid3hctx_rtt); }/*
@@ -336,8 +339,8 @@ static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) hctx->ccid3hctx_x =rfc3390_initial_rate (sk); hctx->ccid3hctx_t_ld = now; }else { -/* Sender does not have RTT sample: X = MSS/second */ - hctx->ccid3hctx_x = dp->dccps_mss_cache; +/* Sender does not have RTT sample: X_pps = 1 pkt/sec */ + hctx->ccid3hctx_x = hctx->ccid3hctx_s; hctx->ccid3hctx_x <<=6 ; }ccid3_update_send_interval (hctx);
Signature · 1 line
1.5.2.2.238.g7cbf2f2-dirty