RTO connection timeout: coding style fixes and comments

This patch affects the retransmits_timed_out() function.

Changes:
1) Variables have more meaningful names
2) retransmits_timed_out() has an introductionary comment.
3) Small coding style changes.

Signed-off-by: Damian Lukowski <damian@tvk.rwth-aachen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Damian Lukowski 2009-09-01 10:24:00 +00:00 committed by David S. Miller
parent 72c6068328
commit 5152fc7de3

View File

@ -1252,22 +1252,27 @@ static inline struct sk_buff *tcp_write_queue_prev(struct sock *sk, struct sk_bu
#define tcp_for_write_queue_from_safe(skb, tmp, sk) \
skb_queue_walk_from_safe(&(sk)->sk_write_queue, skb, tmp)
/* This function calculates a "timeout" which is equivalent to the timeout of a
* TCP connection after "boundary" unsucessful, exponentially backed-off
* retransmissions with an initial RTO of TCP_RTO_MIN.
*/
static inline bool retransmits_timed_out(const struct sock *sk,
unsigned int boundary)
{
int limit, K;
unsigned int timeout, linear_backoff_thresh;
if (!inet_csk(sk)->icsk_retransmits)
return false;
K = ilog2(TCP_RTO_MAX/TCP_RTO_MIN);
linear_backoff_thresh = ilog2(TCP_RTO_MAX/TCP_RTO_MIN);
if (boundary <= K)
limit = ((2 << boundary) - 1) * TCP_RTO_MIN;
if (boundary <= linear_backoff_thresh)
timeout = ((2 << boundary) - 1) * TCP_RTO_MIN;
else
limit = ((2 << K) - 1) * TCP_RTO_MIN +
(boundary - K) * TCP_RTO_MAX;
timeout = ((2 << linear_backoff_thresh) - 1) * TCP_RTO_MIN +
(boundary - linear_backoff_thresh) * TCP_RTO_MAX;
return (tcp_time_stamp - tcp_sk(sk)->retrans_stamp) >= limit;
return (tcp_time_stamp - tcp_sk(sk)->retrans_stamp) >= timeout;
}
static inline struct sk_buff *tcp_send_head(struct sock *sk)