Date: Thu, 15 Apr 2010 10:14:17 -0400 From: John Baldwin <jhb@freebsd.org> To: freebsd-hackers@freebsd.org Cc: Lawrence Stewart <lstewart@freebsd.org>, tuexen@freebsd.org, rrs@freebsd.org Subject: Re: A cookie for anyone who can solve this C/macro problem... Message-ID: <201004151014.17405.jhb@freebsd.org> In-Reply-To: <4BC711DA.4080207@freebsd.org> References: <4BC711DA.4080207@freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thursday 15 April 2010 9:17:14 am Lawrence Stewart wrote:
> void
> newreno_ack_received(struct cc_var *ccv)
> {
> u_int cw = CCV_DO(ccv, snd_cwnd);
> ...
> CCVC(ccv, snd_cwnd = blah);
> }
>
> Of course, this falls apart if you try do this for example:
>
> CCVC(ccv, snd_cwnd = min(blah, bleh));
>
>
> So... I'm sure there are some good ideas out there and would really
> appreciate hearing about them.
If you want to go this route, you could use separate _SET and _GET macros ala
PCPU_*(). Then you would end up with something like:
u_int cw = CCV_GET(ccv, snd_cwnd);
CCV_SET(ccv, snd_cwnd, min(blah, bleh));
--
John Baldwin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201004151014.17405.jhb>