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[TCP]: Kill extra cwnd validate in __tcp_push_pending_frames(). 

The tcp_cwnd_validate() function should only be invoked
if we actually send some frames, yet __tcp_push_pending_frames()
will always invoke it.  tcp_write_xmit() does the call for us,
so the call here can simply be removed.

Also, tcp_write_xmit() can be marked static.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2005-07-05 15:18:51 -07:00
parent f44b527177
commit a762a98007
2 changed files with 52 additions and 53 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
include/net/tcp.h
View File

@ -848,7 +848,6 @@ extern __u32 cookie_v4_init_sequence(struct sock *sk, struct sk_buff *skb,
/* tcp_output.c */
extern int tcp_write_xmit(struct sock *, int nonagle);
extern void __tcp_data_snd_check(struct sock *sk, struct sk_buff *skb);
extern void __tcp_push_pending_frames(struct sock *sk, struct tcp_sock *tp,
unsigned cur_mss, int nonagle);
@ -868,6 +867,9 @@ extern void tcp_push_one(struct sock *, unsigned mss_now);
extern void tcp_send_ack(struct sock *sk);
extern void tcp_send_delayed_ack(struct sock *sk);
/* tcp_input.c */
extern void tcp_cwnd_application_limited(struct sock *sk);
/* tcp_timer.c */
extern void tcp_init_xmit_timers(struct sock *);
extern void tcp_clear_xmit_timers(struct sock *);
@ -1234,28 +1236,6 @@ static inline void tcp_sync_left_out(struct tcp_sock *tp)
tp->left_out = tp->sacked_out + tp->lost_out;
}
extern void tcp_cwnd_application_limited(struct sock *sk);
/* Congestion window validation. (RFC2861) */
static inline void tcp_cwnd_validate(struct sock *sk, struct tcp_sock *tp)
{
__u32 packets_out = tp->packets_out;
if (packets_out >= tp->snd_cwnd) {
/* Network is feed fully. */
tp->snd_cwnd_used = 0;
tp->snd_cwnd_stamp = tcp_time_stamp;
} else {
/* Network starves. */
if (tp->packets_out > tp->snd_cwnd_used)
tp->snd_cwnd_used = tp->packets_out;
if ((s32)(tcp_time_stamp - tp->snd_cwnd_stamp) >= tp->rto)
tcp_cwnd_application_limited(sk);
}
}
/* Set slow start threshould and cwnd not falling to slow start */
static inline void __tcp_enter_cwr(struct tcp_sock *tp)
{

79
net/ipv4/tcp_output.c
View File

@ -511,35 +511,6 @@ static inline int tcp_skb_is_last(const struct sock *sk,
return skb->next == (struct sk_buff *)&sk->sk_write_queue;
}
/* Push out any pending frames which were held back due to
* TCP_CORK or attempt at coalescing tiny packets.
* The socket must be locked by the caller.
*/
void __tcp_push_pending_frames(struct sock *sk, struct tcp_sock *tp,
unsigned cur_mss, int nonagle)
{
struct sk_buff *skb = sk->sk_send_head;
if (skb) {
if (!tcp_skb_is_last(sk, skb))
nonagle = TCP_NAGLE_PUSH;
if (!tcp_snd_test(sk, skb, cur_mss, nonagle) ||
tcp_write_xmit(sk, nonagle))
tcp_check_probe_timer(sk, tp);
}
tcp_cwnd_validate(sk, tp);
}
void __tcp_data_snd_check(struct sock *sk, struct sk_buff *skb)
{
struct tcp_sock *tp = tcp_sk(sk);
if (after(TCP_SKB_CB(skb)->end_seq, tp->snd_una + tp->snd_wnd) ||
tcp_packets_in_flight(tp) >= tp->snd_cwnd ||
tcp_write_xmit(sk, tp->nonagle))
tcp_check_probe_timer(sk, tp);
}
int tcp_may_send_now(struct sock *sk, struct tcp_sock *tp)
{
struct sk_buff *skb = sk->sk_send_head;
@ -841,6 +812,26 @@ unsigned int tcp_current_mss(struct sock *sk, int large)
return mss_now;
}
/* Congestion window validation. (RFC2861) */
static inline void tcp_cwnd_validate(struct sock *sk, struct tcp_sock *tp)
{
__u32 packets_out = tp->packets_out;
if (packets_out >= tp->snd_cwnd) {
/* Network is feed fully. */
tp->snd_cwnd_used = 0;
tp->snd_cwnd_stamp = tcp_time_stamp;
} else {
/* Network starves. */
if (tp->packets_out > tp->snd_cwnd_used)
tp->snd_cwnd_used = tp->packets_out;
if ((s32)(tcp_time_stamp - tp->snd_cwnd_stamp) >= tp->rto)
tcp_cwnd_application_limited(sk);
}
}
/* This routine writes packets to the network. It advances the
* send_head. This happens as incoming acks open up the remote
* window for us.
@ -848,7 +839,7 @@ unsigned int tcp_current_mss(struct sock *sk, int large)
* Returns 1, if no segments are in flight and we have queued segments, but
* cannot send anything now because of SWS or another problem.
*/
int tcp_write_xmit(struct sock *sk, int nonagle)
static int tcp_write_xmit(struct sock *sk, int nonagle)
{
struct tcp_sock *tp = tcp_sk(sk);
unsigned int mss_now;
@ -901,6 +892,34 @@ int tcp_write_xmit(struct sock *sk, int nonagle)
return 0;
}
/* Push out any pending frames which were held back due to
* TCP_CORK or attempt at coalescing tiny packets.
* The socket must be locked by the caller.
*/
void __tcp_push_pending_frames(struct sock *sk, struct tcp_sock *tp,
unsigned cur_mss, int nonagle)
{
struct sk_buff *skb = sk->sk_send_head;
if (skb) {
if (!tcp_skb_is_last(sk, skb))
nonagle = TCP_NAGLE_PUSH;
if (!tcp_snd_test(sk, skb, cur_mss, nonagle) ||
tcp_write_xmit(sk, nonagle))
tcp_check_probe_timer(sk, tp);
}
}
void __tcp_data_snd_check(struct sock *sk, struct sk_buff *skb)
{
struct tcp_sock *tp = tcp_sk(sk);
if (after(TCP_SKB_CB(skb)->end_seq, tp->snd_una + tp->snd_wnd) ||
tcp_packets_in_flight(tp) >= tp->snd_cwnd ||
tcp_write_xmit(sk, tp->nonagle))
tcp_check_probe_timer(sk, tp);
}
/* This function returns the amount that we can raise the
* usable window based on the following constraints
*