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[TCP]: cleanup tcp_{in,out}put.c style 

These were manually selected from indent's results which as is
are too noisy to be of any use without human reason. In addition,
some extra newlines between function and its comment were removed
too.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ilpo Järvinen 2007-12-31 14:57:14 -08:00 committed by David S. Miller
parent 058dc3342b
commit 056834d9f6
2 changed files with 300 additions and 282 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

436
net/ipv4/tcp_input.c
View File

File diff suppressed because it is too large Load Diff

146
net/ipv4/tcp_output.c
View File

@ -221,14 +221,14 @@ void tcp_select_initial_window(int __space, __u32 mss,
* following RFC2414. Senders, not following this RFC,
* will be satisfied with 2.
*/
if (mss > (1<<*rcv_wscale)) {
if (mss > (1 << *rcv_wscale)) {
int init_cwnd = 4;
if (mss > 1460*3)
if (mss > 1460 * 3)
init_cwnd = 2;
else if (mss > 1460)
init_cwnd = 3;
if (*rcv_wnd > init_cwnd*mss)
*rcv_wnd = init_cwnd*mss;
if (*rcv_wnd > init_cwnd * mss)
*rcv_wnd = init_cwnd * mss;
}
/* Set the clamp no higher than max representable value */
@ -278,11 +278,10 @@ static u16 tcp_select_window(struct sock *sk)
return new_win;
}
static inline void TCP_ECN_send_synack(struct tcp_sock *tp,
struct sk_buff *skb)
static inline void TCP_ECN_send_synack(struct tcp_sock *tp, struct sk_buff *skb)
{
TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_CWR;
if (!(tp->ecn_flags&TCP_ECN_OK))
if (!(tp->ecn_flags & TCP_ECN_OK))
TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_ECE;
}
@ -292,7 +291,7 @@ static inline void TCP_ECN_send_syn(struct sock *sk, struct sk_buff *skb)
tp->ecn_flags = 0;
if (sysctl_tcp_ecn) {
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE|TCPCB_FLAG_CWR;
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE | TCPCB_FLAG_CWR;
tp->ecn_flags = TCP_ECN_OK;
}
}
@ -314,7 +313,7 @@ static inline void TCP_ECN_send(struct sock *sk, struct sk_buff *skb,
if (skb->len != tcp_header_len &&
!before(TCP_SKB_CB(skb)->seq, tp->snd_nxt)) {
INET_ECN_xmit(sk);
if (tp->ecn_flags&TCP_ECN_QUEUE_CWR) {
if (tp->ecn_flags & TCP_ECN_QUEUE_CWR) {
tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR;
tcp_hdr(skb)->cwr = 1;
skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
@ -431,7 +430,7 @@ static void tcp_syn_build_options(__be32 *ptr, int mss, int ts, int sack,
(TCPOPT_NOP << 16) |
(TCPOPT_MD5SIG << 8) |
TCPOLEN_MD5SIG);
*md5_hash = (__u8 *) ptr;
*md5_hash = (__u8 *)ptr;
}
#endif
}
@ -447,7 +446,8 @@ static void tcp_syn_build_options(__be32 *ptr, int mss, int ts, int sack,
* We are working here with either a clone of the original
* SKB, or a fresh unique copy made by the retransmit engine.
*/
static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, gfp_t gfp_mask)
static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
gfp_t gfp_mask)
{
const struct inet_connection_sock *icsk = inet_csk(sk);
struct inet_sock *inet;
@ -551,8 +551,8 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
th->urg_ptr = 0;
if (unlikely(tp->urg_mode &&
between(tp->snd_up, tcb->seq+1, tcb->seq+0xFFFF))) {
th->urg_ptr = htons(tp->snd_up-tcb->seq);
between(tp->snd_up, tcb->seq + 1, tcb->seq + 0xFFFF))) {
th->urg_ptr = htons(tp->snd_up - tcb->seq);
th->urg = 1;
}
@ -616,7 +616,6 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
#undef SYSCTL_FLAG_SACK
}
/* This routine just queue's the buffer
*
* NOTE: probe0 timer is not checked, do not forget tcp_push_pending_frames,
@ -634,7 +633,8 @@ static void tcp_queue_skb(struct sock *sk, struct sk_buff *skb)
sk_mem_charge(sk, skb->truesize);
}
static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned int mss_now)
static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb,
unsigned int mss_now)
{
if (skb->len <= mss_now || !sk_can_gso(sk)) {
/* Avoid the costly divide in the normal
@ -670,7 +670,8 @@ static void tcp_adjust_fackets_out(struct sock *sk, struct sk_buff *skb,
* packet to the list. This won't be called frequently, I hope.
* Remember, these are still headerless SKBs at this point.
*/
int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss_now)
int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
unsigned int mss_now)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *buff;
@ -708,13 +709,14 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss
/* PSH and FIN should only be set in the second packet. */
flags = TCP_SKB_CB(skb)->flags;
TCP_SKB_CB(skb)->flags = flags & ~(TCPCB_FLAG_FIN|TCPCB_FLAG_PSH);
TCP_SKB_CB(skb)->flags = flags & ~(TCPCB_FLAG_FIN | TCPCB_FLAG_PSH);
TCP_SKB_CB(buff)->flags = flags;
TCP_SKB_CB(buff)->sacked = TCP_SKB_CB(skb)->sacked;
if (!skb_shinfo(skb)->nr_frags && skb->ip_summed != CHECKSUM_PARTIAL) {
/* Copy and checksum data tail into the new buffer. */
buff->csum = csum_partial_copy_nocheck(skb->data + len, skb_put(buff, nsize),
buff->csum = csum_partial_copy_nocheck(skb->data + len,
skb_put(buff, nsize),
nsize, 0);
skb_trim(skb, len);
@ -781,7 +783,7 @@ static void __pskb_trim_head(struct sk_buff *skb, int len)
eat = len;
k = 0;
for (i=0; i<skb_shinfo(skb)->nr_frags; i++) {
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
if (skb_shinfo(skb)->frags[i].size <= eat) {
put_page(skb_shinfo(skb)->frags[i].page);
eat -= skb_shinfo(skb)->frags[i].size;
@ -804,8 +806,7 @@ static void __pskb_trim_head(struct sk_buff *skb, int len)
int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len)
{
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
return -ENOMEM;
/* If len == headlen, we avoid __skb_pull to preserve alignment. */
@ -909,7 +910,6 @@ void tcp_mtup_init(struct sock *sk)
NOTE2. inet_csk(sk)->icsk_pmtu_cookie and tp->mss_cache
are READ ONLY outside this function. --ANK (980731)
*/
unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu)
{
struct tcp_sock *tp = tcp_sk(sk);
@ -922,8 +922,8 @@ unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu)
mss_now = tcp_mtu_to_mss(sk, pmtu);
/* Bound mss with half of window */
if (tp->max_window && mss_now > (tp->max_window>>1))
mss_now = max((tp->max_window>>1), 68U - tp->tcp_header_len);
if (tp->max_window && mss_now > (tp->max_window >> 1))
mss_now = max((tp->max_window >> 1), 68U - tp->tcp_header_len);
/* And store cached results */
icsk->icsk_pmtu_cookie = pmtu;
@ -977,8 +977,7 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed)
inet_csk(sk)->icsk_ext_hdr_len -
tp->tcp_header_len);
if (tp->max_window &&
(xmit_size_goal > (tp->max_window >> 1)))
if (tp->max_window && (xmit_size_goal > (tp->max_window >> 1)))
xmit_size_goal = max((tp->max_window >> 1),
68U - tp->tcp_header_len);
@ -990,7 +989,6 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed)
}
/* Congestion window validation. (RFC2861) */
static void tcp_cwnd_validate(struct sock *sk)
{
struct tcp_sock *tp = tcp_sk(sk);
@ -1017,8 +1015,7 @@ static void tcp_cwnd_validate(struct sock *sk)
* per input skb which could be mostly avoided here (if desired).
*/
static unsigned int tcp_mss_split_point(struct sock *sk, struct sk_buff *skb,
unsigned int mss_now,
unsigned int cwnd)
unsigned int mss_now, unsigned int cwnd)
{
struct tcp_sock *tp = tcp_sk(sk);
u32 needed, window, cwnd_len;
@ -1039,7 +1036,8 @@ static unsigned int tcp_mss_split_point(struct sock *sk, struct sk_buff *skb,
/* Can at least one segment of SKB be sent right now, according to the
* congestion window rules? If so, return how many segments are allowed.
*/
static inline unsigned int tcp_cwnd_test(struct tcp_sock *tp, struct sk_buff *skb)
static inline unsigned int tcp_cwnd_test(struct tcp_sock *tp,
struct sk_buff *skb)
{
u32 in_flight, cwnd;
@ -1059,13 +1057,12 @@ static inline unsigned int tcp_cwnd_test(struct tcp_sock *tp, struct sk_buff *sk
/* This must be invoked the first time we consider transmitting
* SKB onto the wire.
*/
static int tcp_init_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned int mss_now)
static int tcp_init_tso_segs(struct sock *sk, struct sk_buff *skb,
unsigned int mss_now)
{
int tso_segs = tcp_skb_pcount(skb);
if (!tso_segs ||
(tso_segs > 1 &&
tcp_skb_mss(skb) != mss_now)) {
if (!tso_segs || (tso_segs > 1 && tcp_skb_mss(skb) != mss_now)) {
tcp_set_skb_tso_segs(sk, skb, mss_now);
tso_segs = tcp_skb_pcount(skb);
}
@ -1085,16 +1082,13 @@ static inline int tcp_minshall_check(const struct tcp_sock *tp)
* 4. Or TCP_CORK is not set, and all sent packets are ACKed.
* With Minshall's modification: all sent small packets are ACKed.
*/
static inline int tcp_nagle_check(const struct tcp_sock *tp,
const struct sk_buff *skb,
unsigned mss_now, int nonagle)
{
return (skb->len < mss_now &&
((nonagle&TCP_NAGLE_CORK) ||
(!nonagle &&
tp->packets_out &&
tcp_minshall_check(tp))));
((nonagle & TCP_NAGLE_CORK) ||
(!nonagle && tp->packets_out && tcp_minshall_check(tp))));
}
/* Return non-zero if the Nagle test allows this packet to be
@ -1126,7 +1120,8 @@ static inline int tcp_nagle_test(struct tcp_sock *tp, struct sk_buff *skb,
}
/* Does at least the first segment of SKB fit into the send window? */
static inline int tcp_snd_wnd_test(struct tcp_sock *tp, struct sk_buff *skb, unsigned int cur_mss)
static inline int tcp_snd_wnd_test(struct tcp_sock *tp, struct sk_buff *skb,
unsigned int cur_mss)
{
u32 end_seq = TCP_SKB_CB(skb)->end_seq;
@ -1152,8 +1147,7 @@ static unsigned int tcp_snd_test(struct sock *sk, struct sk_buff *skb,
return 0;
cwnd_quota = tcp_cwnd_test(tp, skb);
if (cwnd_quota &&
!tcp_snd_wnd_test(tp, skb, cur_mss))
if (cwnd_quota && !tcp_snd_wnd_test(tp, skb, cur_mss))
cwnd_quota = 0;
return cwnd_quota;
@ -1177,7 +1171,8 @@ int tcp_may_send_now(struct sock *sk)
* know that all the data is in scatter-gather pages, and that the
* packet has never been sent out before (and thus is not cloned).
*/
static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len, unsigned int mss_now)
static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
unsigned int mss_now)
{
struct sk_buff *buff;
int nlen = skb->len - len;
@ -1203,7 +1198,7 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
/* PSH and FIN should only be set in the second packet. */
flags = TCP_SKB_CB(skb)->flags;
TCP_SKB_CB(skb)->flags = flags & ~(TCPCB_FLAG_FIN|TCPCB_FLAG_PSH);
TCP_SKB_CB(skb)->flags = flags & ~(TCPCB_FLAG_FIN | TCPCB_FLAG_PSH);
TCP_SKB_CB(buff)->flags = flags;
/* This packet was never sent out yet, so no SACK bits. */
@ -1247,8 +1242,7 @@ static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
in_flight = tcp_packets_in_flight(tp);
BUG_ON(tcp_skb_pcount(skb) <= 1 ||
(tp->snd_cwnd <= in_flight));
BUG_ON(tcp_skb_pcount(skb) <= 1 || (tp->snd_cwnd <= in_flight));
send_win = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
@ -1281,7 +1275,7 @@ static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
}
/* Ok, it looks like it is advisable to defer. */
tp->tso_deferred = 1 | (jiffies<<1);
tp->tso_deferred = 1 | (jiffies << 1);
return 1;
@ -1293,7 +1287,8 @@ static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
/* Create a new MTU probe if we are ready.
* Returns 0 if we should wait to probe (no cwnd available),
* 1 if a probe was sent,
* -1 otherwise */
* -1 otherwise
*/
static int tcp_mtu_probe(struct sock *sk)
{
struct tcp_sock *tp = tcp_sk(sk);
@ -1318,7 +1313,7 @@ static int tcp_mtu_probe(struct sock *sk)
/* Very simple search strategy: just double the MSS. */
mss_now = tcp_current_mss(sk, 0);
probe_size = 2*tp->mss_cache;
probe_size = 2 * tp->mss_cache;
size_needed = probe_size + (tp->reordering + 1) * tp->mss_cache;
if (probe_size > tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_high)) {
/* TODO: set timer for probe_converge_event */
@ -1366,7 +1361,8 @@ static int tcp_mtu_probe(struct sock *sk)
skb_copy_bits(skb, 0, skb_put(nskb, copy), copy);
else
nskb->csum = skb_copy_and_csum_bits(skb, 0,
skb_put(nskb, copy), copy, nskb->csum);
skb_put(nskb, copy),
copy, nskb->csum);
if (skb->len <= copy) {
/* We've eaten all the data from this skb.
@ -1380,7 +1376,8 @@ static int tcp_mtu_probe(struct sock *sk)
if (!skb_shinfo(skb)->nr_frags) {
skb_pull(skb, copy);
if (skb->ip_summed != CHECKSUM_PARTIAL)
skb->csum = csum_partial(skb->data, skb->len, 0);
skb->csum = csum_partial(skb->data,
skb->len, 0);
} else {
__pskb_trim_head(skb, copy);
tcp_set_skb_tso_segs(sk, skb, mss_now);
@ -1400,7 +1397,7 @@ static int tcp_mtu_probe(struct sock *sk)
TCP_SKB_CB(nskb)->when = tcp_time_stamp;
if (!tcp_transmit_skb(sk, nskb, 1, GFP_ATOMIC)) {
/* Decrement cwnd here because we are sending
* effectively two packets. */
* effectively two packets. */
tp->snd_cwnd--;
tcp_event_new_data_sent(sk, nskb);
@ -1414,7 +1411,6 @@ static int tcp_mtu_probe(struct sock *sk)
return -1;
}
/* This routine writes packets to the network. It advances the
* send_head. This happens as incoming acks open up the remote
* window for us.
@ -1626,7 +1622,8 @@ u32 __tcp_select_window(struct sock *sk)
icsk->icsk_ack.quick = 0;
if (tcp_memory_pressure)
tp->rcv_ssthresh = min(tp->rcv_ssthresh, 4U*tp->advmss);
tp->rcv_ssthresh = min(tp->rcv_ssthresh,
4U * tp->advmss);
if (free_space < mss)
return 0;
@ -1659,7 +1656,7 @@ u32 __tcp_select_window(struct sock *sk)
* is too small.
*/
if (window <= free_space - mss || window > free_space)
window = (free_space/mss)*mss;
window = (free_space / mss) * mss;
else if (mss == full_space &&
free_space > window + (full_space >> 1))
window = free_space;
@ -1669,7 +1666,8 @@ u32 __tcp_select_window(struct sock *sk)
}
/* Attempt to collapse two adjacent SKB's during retransmission. */
static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int mss_now)
static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb,
int mss_now)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *next_skb = tcp_write_queue_next(sk, skb);
@ -1762,12 +1760,12 @@ void tcp_simple_retransmit(struct sock *sk)
if (skb == tcp_send_head(sk))
break;
if (skb->len > mss &&
!(TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_ACKED)) {
if (TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_RETRANS) {
!(TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)) {
if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) {
TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
tp->retrans_out -= tcp_skb_pcount(skb);
}
if (!(TCP_SKB_CB(skb)->sacked&TCPCB_LOST)) {
if (!(TCP_SKB_CB(skb)->sacked & TCPCB_LOST)) {
TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
tp->lost_out += tcp_skb_pcount(skb);
lost = 1;
@ -1846,8 +1844,10 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
(skb->len < (cur_mss >> 1)) &&
(tcp_write_queue_next(sk, skb) != tcp_send_head(sk)) &&
(!tcp_skb_is_last(sk, skb)) &&
(skb_shinfo(skb)->nr_frags == 0 && skb_shinfo(tcp_write_queue_next(sk, skb))->nr_frags == 0) &&
(tcp_skb_pcount(skb) == 1 && tcp_skb_pcount(tcp_write_queue_next(sk, skb)) == 1) &&
(skb_shinfo(skb)->nr_frags == 0 &&
skb_shinfo(tcp_write_queue_next(sk, skb))->nr_frags == 0) &&
(tcp_skb_pcount(skb) == 1 &&
tcp_skb_pcount(tcp_write_queue_next(sk, skb)) == 1) &&
(sysctl_tcp_retrans_collapse != 0))
tcp_retrans_try_collapse(sk, skb, cur_mss);
@ -1885,7 +1885,7 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
tp->total_retrans++;
#if FASTRETRANS_DEBUG > 0
if (TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_RETRANS) {
if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) {
if (net_ratelimit())
printk(KERN_DEBUG "retrans_out leaked.\n");
}
@ -1927,7 +1927,7 @@ void tcp_xmit_retransmit_queue(struct sock *sk)
if (tp->retransmit_skb_hint) {
skb = tp->retransmit_skb_hint;
packet_cnt = tp->retransmit_cnt_hint;
}else{
} else {
skb = tcp_write_queue_head(sk);
packet_cnt = 0;
}
@ -1954,7 +1954,7 @@ void tcp_xmit_retransmit_queue(struct sock *sk)
return;
if (sacked & TCPCB_LOST) {
if (!(sacked&(TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS))) {
if (!(sacked & (TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS))) {
if (tcp_retransmit_skb(sk, skb)) {
tp->retransmit_skb_hint = NULL;
return;
@ -2036,7 +2036,6 @@ void tcp_xmit_retransmit_queue(struct sock *sk)
}
}
/* Send a fin. The caller locks the socket for us. This cannot be
* allowed to fail queueing a FIN frame under any circumstances.
*/
@ -2122,14 +2121,14 @@ void tcp_send_active_reset(struct sock *sk, gfp_t priority)
*/
int tcp_send_synack(struct sock *sk)
{
struct sk_buff* skb;
struct sk_buff *skb;
skb = tcp_write_queue_head(sk);
if (skb == NULL || !(TCP_SKB_CB(skb)->flags&TCPCB_FLAG_SYN)) {
if (skb == NULL || !(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_SYN)) {
printk(KERN_DEBUG "tcp_send_synack: wrong queue state\n");
return -EFAULT;
}
if (!(TCP_SKB_CB(skb)->flags&TCPCB_FLAG_ACK)) {
if (!(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_ACK)) {
if (skb_cloned(skb)) {
struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
if (nskb == NULL)
@ -2153,8 +2152,8 @@ int tcp_send_synack(struct sock *sk)
/*
* Prepare a SYN-ACK.
*/
struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst,
struct request_sock *req)
struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
struct request_sock *req)
{
struct inet_request_sock *ireq = inet_rsk(req);
struct tcp_sock *tp = tcp_sk(sk);
@ -2372,9 +2371,10 @@ void tcp_send_delayed_ack(struct sock *sk)
if (ato > TCP_DELACK_MIN) {
const struct tcp_sock *tp = tcp_sk(sk);
int max_ato = HZ/2;
int max_ato = HZ / 2;
if (icsk->icsk_ack.pingpong || (icsk->icsk_ack.pending & ICSK_ACK_PUSHED))
if (icsk->icsk_ack.pingpong ||
(icsk->icsk_ack.pending & ICSK_ACK_PUSHED))
max_ato = TCP_DELACK_MAX;
/* Slow path, intersegment interval is "high". */
@ -2384,7 +2384,7 @@ void tcp_send_delayed_ack(struct sock *sk)
* directly.
*/
if (tp->srtt) {
int rtt = max(tp->srtt>>3, TCP_DELACK_MIN);
int rtt = max(tp->srtt >> 3, TCP_DELACK_MIN);
if (rtt < max_ato)
max_ato = rtt;