[DCCP] ccid3: Consolidate timer resets

This patch concerns updating the value of the nofeedback timer when no feedback
has been received so far.

Since in this case the value of R is still undefined according to [RFC 3448,
4.2], we can not perform step (3) of [RFC 3448, 4.3].  A clarification is
provided in [RFC 4342, sec. 5], which states that in these cases the nofeedback
timer (still) expires "after two seconds".

Many thanks to Ian McDonald for pointing this out and providing the
clarification.

The patch
  * implements [RFC 4342, sec. 5] with regard to the above case
  * consolidates handling timer restart by
	- adding an appropriate jump label and
	- initialising the timeout value

Acked-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 2006-11-27 20:29:27 -02:00 committed by David S. Miller
parent b798a9ede2
commit 48e03eee71
2 changed files with 10 additions and 10 deletions

View file

@ -154,16 +154,14 @@ static void ccid3_hc_tx_update_x(struct sock *sk)
static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
{
struct sock *sk = (struct sock *)data;
unsigned long next_tmout = 0;
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
unsigned long next_tmout = USEC_PER_SEC / 5;
bh_lock_sock(sk);
if (sock_owned_by_user(sk)) {
/* Try again later. */
/* XXX: set some sensible MIB */
sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
jiffies + HZ / 5);
goto out;
goto restart_timer;
}
ccid3_pr_debug("%s, sk=%p, state=%s\n", dccp_role(sk), sk,
@ -183,9 +181,9 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
dccp_role(sk), sk,
ccid3_tx_state_name(hctx->ccid3hctx_state),
hctx->ccid3hctx_x);
next_tmout = max_t(u32, 2 * usecs_div(hctx->ccid3hctx_s,
hctx->ccid3hctx_x),
TFRC_INITIAL_TIMEOUT);
/* 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;
/*
* FIXME - not sure above calculation is correct. See section
* 5 of CCID3 11 should adjust tx_t_ipi and double that to
@ -239,9 +237,11 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
goto out;
}
sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
jiffies + max_t(u32, 1, usecs_to_jiffies(next_tmout)));
hctx->ccid3hctx_idle = 1;
restart_timer:
sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
jiffies + usecs_to_jiffies(next_tmout));
out:
bh_unlock_sock(sk);
sock_put(sk);

View file

@ -46,7 +46,7 @@
#define TFRC_STD_PACKET_SIZE 256
#define TFRC_MAX_PACKET_SIZE 65535
/* Two seconds as per CCID3 spec */
/* Two seconds as per RFC 3448 4.2 */
#define TFRC_INITIAL_TIMEOUT (2 * USEC_PER_SEC)
/* In usecs - half the scheduling granularity as per RFC3448 4.6 */