diff options
| author |   Gerrit Renker <gerrit@erg.abdn.ac.uk> | 2007-11-20 18:01:59 -0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2008-01-28 14:54:42 -0800 |
| commit | a5358fdc9c52e44d79dcd144375e089e166508d7 (patch) | |
| tree | ddd84d7a6115700ff93f24d367d59c8ad03a9adc /net/dccp/ccids/ccid3.c | |
| parent | [CCID3]: Ignore trivial amounts of elapsed time (diff) | |
| download | linux-dev-a5358fdc9c52e44d79dcd144375e089e166508d7.tar.xz linux-dev-a5358fdc9c52e44d79dcd144375e089e166508d7.zip | |
[CCID3]: Accurately determine idle & application-limited periods
This fixes/updates the handling of idle and application-limited periods in CCID3,
which currently is broken: there is no detection as to how long a sender has been
idle - there is only one flag which is toggled in between function calls.
Being obsolete now, the `idle' flag is removed.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/dccp/ccids/ccid3.c')
| -rw-r--r-- | net/dccp/ccids/ccid3.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index c025236ce49b..94a322863844 100644 --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c @@ -119,6 +119,13 @@ static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx) } +static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hctx, ktime_t now) +{ + u32 delta = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count); + + return delta / hctx->ccid3hctx_rtt; +} + /** * ccid3_hc_tx_update_x - Update allowed sending rate X * @stamp: most recent time if available - can be left NULL. @@ -139,10 +146,11 @@ static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp) /* * Handle IDLE periods: do not reduce below RFC3390 initial sending rate - * when idling [RFC 4342, 5.1]. See also draft-ietf-dccp-rfc3448bis. + * when idling [RFC 4342, 5.1]. Definition of idling is from rfc3448bis: + * a sender is idle if it has not sent anything over a 2-RTT-period. * For consistency with X and X_recv, min_rate is also scaled by 2^6. */ - if (unlikely(hctx->ccid3hctx_idle)) { + if (ccid3_hc_tx_idle_rtt(hctx, now) >= 2) { min_rate = rfc3390_initial_rate(sk); min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv); } @@ -228,8 +236,6 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data) ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk, ccid3_tx_state_name(hctx->ccid3hctx_state)); - hctx->ccid3hctx_idle = 1; - switch (hctx->ccid3hctx_state) { case TFRC_SSTATE_NO_FBACK: /* RFC 3448, 4.4: Halve send rate directly */ @@ -372,7 +378,6 @@ static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) /* prepare to send now (add options etc.) */ dp->dccps_hc_tx_insert_options = 1; DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; - hctx->ccid3hctx_idle = 0; /* set the nominal send time for the next following packet */ hctx->ccid3hctx_t_nom = ktime_add_us(hctx->ccid3hctx_t_nom, @@ -531,9 +536,6 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, jiffies + usecs_to_jiffies(t_nfb)); - - /* set idle flag */ - hctx->ccid3hctx_idle = 1; break; case TFRC_SSTATE_NO_SENT: /* fall through */ case TFRC_SSTATE_TERM: /* ignore feedback when closing */ |