[DCCP] ccid3: Set NoFeedback Timeout according to RFC 3448

This corrects the setting of the nofeedback timer with regard to RFC
3448 - previously it was not set to max(4*R, 2*s/X) as specified. Using
the maximum of 1 second as upper bound (as it was done before) can have
detrimental effects, especially if R is small.

Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This commit is contained in:
Gerrit Renker 2006-11-28 18:34:34 -02:00 committed by David S. Miller
parent 4384260443
commit 2a1fda6f6c
1 changed files with 10 additions and 12 deletions

View File

@ -163,7 +163,7 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
{
struct sock *sk = (struct sock *)data;
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
unsigned long next_tmout = USEC_PER_SEC / 5;
unsigned long t_nfb = USEC_PER_SEC / 5;
bh_lock_sock(sk);
if (sock_owned_by_user(sk)) {
@ -191,7 +191,7 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
hctx->ccid3hctx_x);
/* The value of R is still undefined and so we can not recompute
* the timout value. Keep initial value as per [RFC 4342, 5]. */
next_tmout = TFRC_INITIAL_TIMEOUT;
t_nfb = TFRC_INITIAL_TIMEOUT;
ccid3_update_send_time(hctx);
break;
case TFRC_SSTATE_FBACK:
@ -228,10 +228,9 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
}
/*
* Schedule no feedback timer to expire in
* max(4 * t_RTO, 2 * s/X) = max(4 * t_RTO, 2 * t_ipi)
* XXX This is non-standard, RFC 3448, 4.3 uses 4 * R
* max(4 * R, 2 * s/X) = max(4 * R, 2 * t_ipi)
*/
next_tmout = max(hctx->ccid3hctx_t_rto, 2*hctx->ccid3hctx_t_ipi);
t_nfb = max(4 * hctx->ccid3hctx_rtt, 2 * hctx->ccid3hctx_t_ipi);
break;
case TFRC_SSTATE_NO_SENT:
DCCP_BUG("Illegal %s state NO_SENT, sk=%p", dccp_role(sk), sk);
@ -244,7 +243,7 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
restart_timer:
sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
jiffies + usecs_to_jiffies(next_tmout));
jiffies + usecs_to_jiffies(t_nfb));
out:
bh_unlock_sock(sk);
sock_put(sk);
@ -396,7 +395,7 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
struct ccid3_options_received *opt_recv;
struct dccp_tx_hist_entry *packet;
struct timeval now;
unsigned long next_tmout;
unsigned long t_nfb;
u32 t_elapsed;
u32 pinv;
u32 x_recv;
@ -498,18 +497,17 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
USEC_PER_SEC );
/*
* Schedule no feedback timer to expire in
* max(4 * t_RTO, 2 * s/X) = max(4 * t_RTO, 2 * t_ipi)
* XXX This is non-standard, RFC 3448, 4.3 uses 4 * R
* max(4 * R, 2 * s/X) = max(4 * R, 2 * t_ipi)
*/
next_tmout = max(hctx->ccid3hctx_t_rto, 2*hctx->ccid3hctx_t_ipi);
t_nfb = max(4 * hctx->ccid3hctx_rtt, 2 * hctx->ccid3hctx_t_ipi);
ccid3_pr_debug("%s, sk=%p, Scheduled no feedback timer to "
"expire in %lu jiffies (%luus)\n",
dccp_role(sk), sk,
usecs_to_jiffies(next_tmout), next_tmout);
usecs_to_jiffies(t_nfb), t_nfb);
sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
jiffies + usecs_to_jiffies(next_tmout));
jiffies + usecs_to_jiffies(t_nfb));
/* set idle flag */
hctx->ccid3hctx_idle = 1;