openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

tcp: add helper for counter tweaking due mid-wq change 

We need full-scale adjustment to fix a TCP miscount in the next
patch, so just move it into a helper and call for that from the
other places.

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 2009-04-01 23:15:17 +00:00 committed by David S. Miller
parent 0de8ca597d
commit 797108d134
2 changed files with 34 additions and 47 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
include/net/tcp.h
View File

@ -616,21 +616,6 @@ static inline int tcp_skb_mss(const struct sk_buff *skb)
return skb_shinfo(skb)->gso_size;
}
static inline void tcp_dec_pcount_approx_int(__u32 *count, const int decr)
{
if (*count) {
*count -= decr;
if ((int)*count < 0)
*count = 0;
}
}
static inline void tcp_dec_pcount_approx(__u32 *count,
const struct sk_buff *skb)
{
tcp_dec_pcount_approx_int(count, tcp_skb_pcount(skb));
}
/* Events passed to congestion control interface */
enum tcp_ca_event {
CA_EVENT_TX_START, /* first transmit when no packets in flight */

66
net/ipv4/tcp_output.c
View File

@ -754,6 +754,36 @@ static void tcp_adjust_fackets_out(struct sock *sk, struct sk_buff *skb,
tp->fackets_out -= decr;
}
/* Pcount in the middle of the write queue got changed, we need to do various
* tweaks to fix counters
*/
static void tcp_adjust_pcount(struct sock *sk, struct sk_buff *skb, int decr)
{
struct tcp_sock *tp = tcp_sk(sk);
tp->packets_out -= decr;
if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)
tp->sacked_out -= decr;
if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS)
tp->retrans_out -= decr;
if (TCP_SKB_CB(skb)->sacked & TCPCB_LOST)
tp->lost_out -= decr;
/* Reno case is special. Sigh... */
if (tcp_is_reno(tp) && decr > 0)
tp->sacked_out -= min_t(u32, tp->sacked_out, decr);
tcp_adjust_fackets_out(sk, skb, decr);
if (tp->lost_skb_hint &&
before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(tp->lost_skb_hint)->seq) &&
(tcp_is_fack(tp) || TCP_SKB_CB(skb)->sacked))
tp->lost_cnt_hint -= decr;
tcp_verify_left_out(tp);
}
/* Function to create two new TCP segments. Shrinks the given segment
* to the specified size and appends a new segment with the rest of the
* packet to the list. This won't be called frequently, I hope.
@ -836,28 +866,8 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
int diff = old_factor - tcp_skb_pcount(skb) -
tcp_skb_pcount(buff);
tp->packets_out -= diff;
if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)
tp->sacked_out -= diff;
if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS)
tp->retrans_out -= diff;
if (TCP_SKB_CB(skb)->sacked & TCPCB_LOST)
tp->lost_out -= diff;
/* Adjust Reno SACK estimate. */
if (tcp_is_reno(tp) && diff > 0) {
tcp_dec_pcount_approx_int(&tp->sacked_out, diff);
tcp_verify_left_out(tp);
}
tcp_adjust_fackets_out(sk, skb, diff);
if (tp->lost_skb_hint &&
before(TCP_SKB_CB(skb)->seq,
TCP_SKB_CB(tp->lost_skb_hint)->seq) &&
(tcp_is_fack(tp) || TCP_SKB_CB(skb)->sacked))
tp->lost_cnt_hint -= diff;
if (diff)
tcp_adjust_pcount(sk, skb, diff);
}
/* Link BUFF into the send queue. */
@ -1768,22 +1778,14 @@ static void tcp_collapse_retrans(struct sock *sk, struct sk_buff *skb)
* packet counting does not break.
*/
TCP_SKB_CB(skb)->sacked |= TCP_SKB_CB(next_skb)->sacked & TCPCB_EVER_RETRANS;
if (TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_RETRANS)
tp->retrans_out -= tcp_skb_pcount(next_skb);
if (TCP_SKB_CB(next_skb)->sacked & TCPCB_LOST)
tp->lost_out -= tcp_skb_pcount(next_skb);
/* Reno case is special. Sigh... */
if (tcp_is_reno(tp) && tp->sacked_out)
tcp_dec_pcount_approx(&tp->sacked_out, next_skb);
tcp_adjust_fackets_out(sk, next_skb, tcp_skb_pcount(next_skb));
tp->packets_out -= tcp_skb_pcount(next_skb);
/* changed transmit queue under us so clear hints */
tcp_clear_retrans_hints_partial(tp);
if (next_skb == tp->retransmit_skb_hint)
tp->retransmit_skb_hint = skb;
tcp_adjust_pcount(sk, next_skb, tcp_skb_pcount(next_skb));
sk_wmem_free_skb(sk, next_skb);
}