From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [TCP]: min_t/max_t confusion in tcp_select_initial_window()?
Date: Wed, 23 Dec 2009 13:15:26 -0800 (PST)
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=46rom: "Ilpo J=E4rvinen" <ilpo.jarvinen@helsinki.fi>
Date: Wed, 23 Dec 2009 21:45:57 +0200 (EET)

> On Tue, 22 Dec 2009, David Miller wrote:
>=20
>> From: Roel Kluin <roel.kluin@gmail.com>
>> Date: Wed, 23 Dec 2009 03:00:24 +0100
>>=20
>> > I could be confused, but in net/ipv4/tcp_output.c:217:
>> >=20
>> >                 space =3D max_t(u32, sysctl_tcp_rmem[2], sysctl_rm=
em_max);
>> >                 space =3D min_t(u32, space, *window_clamp);
>> > ------------------------^^^^^
 ...
>=20
> I don't understand how window_clamp line could be changed to max_t.
> ...I guess min in both would seem the most reasonable one?

Nope, the first one must be max.  Since I'm pretty sure we let the
dynamic RX buffer resizing exceed sysctl_rmem_max if necessary.

And that's what is controlled by sysctl_tcp_rmem[2]