[TCP]: Describe tcp_init_cwnd() thoroughly in a comment.

People often get tripped up by this function and think that
it does not implemented the prescribed algorithms from
RFC2414 and RFC3390, even though it does.

So add a comment to head off such misunderstandings in the
future.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2007-08-24 22:21:50 -07:00
parent a96fb49be3
commit 26722873a4
1 changed files with 9 additions and 1 deletions

View File

@ -755,7 +755,15 @@ void tcp_update_metrics(struct sock *sk)
}
}
/* Numbers are taken from RFC2414. */
/* Numbers are taken from RFC3390.
*
* John Heffner states:
*
* The RFC specifies a window of no more than 4380 bytes
* unless 2*MSS > 4380. Reading the pseudocode in the RFC
* is a bit misleading because they use a clamp at 4380 bytes
* rather than use a multiplier in the relevant range.
*/
__u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst)
{
__u32 cwnd = (dst ? dst_metric(dst, RTAX_INITCWND) : 0);