[DCCP]: Introduce tx buffering

This adds transmit buffering to DCCP.

I have tested with CCID2/3 and with loss and rate limiting.

Signed off by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ian McDonald 2006-08-26 19:16:45 -07:00 committed by David S. Miller
parent 2a0109a707
commit 97e5848dd3
4 changed files with 72 additions and 36 deletions

View file

@ -438,6 +438,7 @@ struct dccp_ackvec;
* @dccps_role - Role of this sock, one of %dccp_role
* @dccps_ndp_count - number of Non Data Packets since last data packet
* @dccps_hc_rx_ackvec - rx half connection ack vector
* @dccps_xmit_timer - timer for when CCID is not ready to send
*/
struct dccp_sock {
/* inet_connection_sock has to be the first member of dccp_sock */
@ -470,6 +471,7 @@ struct dccp_sock {
enum dccp_role dccps_role:2;
__u8 dccps_hc_rx_insert_options:1;
__u8 dccps_hc_tx_insert_options:1;
struct timer_list dccps_xmit_timer;
};
static inline struct dccp_sock *dccp_sk(const struct sock *sk)

View file

@ -130,7 +130,7 @@ extern void dccp_send_delayed_ack(struct sock *sk);
extern void dccp_send_sync(struct sock *sk, const u64 seq,
const enum dccp_pkt_type pkt_type);
extern int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo);
extern void dccp_write_xmit(struct sock *sk, int block);
extern void dccp_write_space(struct sock *sk);
extern void dccp_init_xmit_timers(struct sock *sk);

View file

@ -198,7 +198,7 @@ static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb,
while (1) {
prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
if (sk->sk_err)
goto do_error;
if (!*timeo)
goto do_nonblock;
@ -234,37 +234,72 @@ do_interrupted:
goto out;
}
int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo)
static void dccp_write_xmit_timer(unsigned long data) {
struct sock *sk = (struct sock *)data;
struct dccp_sock *dp = dccp_sk(sk);
bh_lock_sock(sk);
if (sock_owned_by_user(sk))
sk_reset_timer(sk, &dp->dccps_xmit_timer, jiffies+1);
else
dccp_write_xmit(sk, 0);
bh_unlock_sock(sk);
sock_put(sk);
}
void dccp_write_xmit(struct sock *sk, int block)
{
const struct dccp_sock *dp = dccp_sk(sk);
int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb,
struct dccp_sock *dp = dccp_sk(sk);
struct sk_buff *skb;
long timeo = 30000; /* If a packet is taking longer than 2 secs
we have other issues */
while ((skb = skb_peek(&sk->sk_write_queue))) {
int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb,
skb->len);
if (err > 0)
err = dccp_wait_for_ccid(sk, skb, timeo);
if (err > 0) {
if (!block) {
sk_reset_timer(sk, &dp->dccps_xmit_timer,
msecs_to_jiffies(err)+jiffies);
break;
} else
err = dccp_wait_for_ccid(sk, skb, &timeo);
if (err) {
printk(KERN_CRIT "%s:err at dccp_wait_for_ccid"
" %d\n", __FUNCTION__, err);
dump_stack();
}
}
if (err == 0) {
struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
const int len = skb->len;
skb_dequeue(&sk->sk_write_queue);
if (err == 0) {
struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
const int len = skb->len;
if (sk->sk_state == DCCP_PARTOPEN) {
/* See 8.1.5. Handshake Completion */
inet_csk_schedule_ack(sk);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
if (sk->sk_state == DCCP_PARTOPEN) {
/* See 8.1.5. Handshake Completion */
inet_csk_schedule_ack(sk);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
inet_csk(sk)->icsk_rto,
DCCP_RTO_MAX);
dcb->dccpd_type = DCCP_PKT_DATAACK;
} else if (dccp_ack_pending(sk))
dcb->dccpd_type = DCCP_PKT_DATAACK;
else
dcb->dccpd_type = DCCP_PKT_DATA;
dcb->dccpd_type = DCCP_PKT_DATAACK;
} else if (dccp_ack_pending(sk))
dcb->dccpd_type = DCCP_PKT_DATAACK;
else
dcb->dccpd_type = DCCP_PKT_DATA;
err = dccp_transmit_skb(sk, skb);
ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, 0, len);
} else
kfree_skb(skb);
return err;
err = dccp_transmit_skb(sk, skb);
ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, 0, len);
if (err) {
printk(KERN_CRIT "%s:err from "
"ccid_hc_tx_packet_sent %d\n",
__FUNCTION__, err);
dump_stack();
}
} else
kfree(skb);
}
}
int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
@ -426,6 +461,9 @@ static inline void dccp_connect_init(struct sock *sk)
dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss));
icsk->icsk_retransmits = 0;
init_timer(&dp->dccps_xmit_timer);
dp->dccps_xmit_timer.data = (unsigned long)sk;
dp->dccps_xmit_timer.function = dccp_write_xmit_timer;
}
int dccp_connect(struct sock *sk)
@ -560,8 +598,10 @@ void dccp_send_close(struct sock *sk, const int active)
DCCP_PKT_CLOSE : DCCP_PKT_CLOSEREQ;
if (active) {
dccp_write_xmit(sk, 1);
dccp_skb_entail(sk, skb);
dccp_transmit_skb(sk, skb_clone(skb, prio));
/* FIXME do we need a retransmit timer here? */
} else
dccp_transmit_skb(sk, skb);
}

View file

@ -662,17 +662,8 @@ int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
if (rc != 0)
goto out_discard;
rc = dccp_write_xmit(sk, skb, &timeo);
/*
* XXX we don't use sk_write_queue, so just discard the packet.
* Current plan however is to _use_ sk_write_queue with
* an algorith similar to tcp_sendmsg, where the main difference
* is that in DCCP we have to respect packet boundaries, so
* no coalescing of skbs.
*
* This bug was _quickly_ found & fixed by just looking at an OSTRA
* generated callgraph 8) -acme
*/
skb_queue_tail(&sk->sk_write_queue, skb);
dccp_write_xmit(sk,0);
out_release:
release_sock(sk);
return rc ? : len;
@ -846,6 +837,7 @@ static int dccp_close_state(struct sock *sk)
void dccp_close(struct sock *sk, long timeout)
{
struct dccp_sock *dp = dccp_sk(sk);
struct sk_buff *skb;
int state;
@ -862,6 +854,8 @@ void dccp_close(struct sock *sk, long timeout)
goto adjudge_to_death;
}
sk_stop_timer(sk, &dp->dccps_xmit_timer);
/*
* We need to flush the recv. buffs. We do this only on the
* descriptor close, not protocol-sourced closes, because the