From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [RFC v2] tcp: Export TCP Delayed ACK parameters to user
Date: Fri, 28 Oct 2011 18:31:07 -0400 (EDT)
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=46rom: Daniel Baluta <dbaluta@ixiacom.com>
Date: Sat, 29 Oct 2011 00:35:24 +0300

> On Sat, Oct 29, 2011 at 12:19 AM, David Miller <davem@davemloft.net> =
wrote:
>> From: Daniel Baluta <dbaluta@ixiacom.com>
>> Date: Sat, 29 Oct 2011 00:14:03 +0300
>>
>>> +static inline int tcp_delack_thresh(const struct sock *sk)
>>> +{
>>> + =A0 =A0 return inet_csk(sk)->icsk_ack.rcv_mss * sysctl_tcp_delack=
_segs;
>>> +}
>>> +
>>
>> Please turn this into a shift or something, you're adding a multiply
>> into a core code path.
>=20
> Is there any generic API to do this? Default case is not
> affected since tcp_delack_segs is 1.

I'm saying make the tunable a shift count instead of something to
multiply against.