From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ben Warren <biggerbadderben@gmail.com>
Date: Thu, 25 Sep 2008 23:09:49 -0700
Subject: [U-Boot] Inefficient code in NetLoop() ?
In-Reply-To: <20080912195058.8625324926@gemini.denx.de>
References: <20080912195058.8625324926@gemini.denx.de>
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To: u-boot@lists.denx.de

Wolfgang Denk wrote:
> Dear Ben,
>
> I just ran over this piece of code in NetLoop() [see "net/net.c"]:
>
>  286 int
>  287 NetLoop(proto_t protocol)
>  288 {
>  ...
>  322         eth_halt();
>  323 #ifdef CONFIG_NET_MULTI
>  324         eth_set_current();
>  325 #endif
>  326         if (eth_init(bd) < 0) {
>  327                 eth_halt();
>  328                 return(-1);
>  329         }
>
> Am I reading this correctly that we  eth_halt()  and  eth_init()  the
> network interface for each and every call to NetLoop?
>
>   
Yes, it looks that way.  Ripe for gutting.
> This looks terribly inefficient to me - is there any rationale behind
> this?
>
>   
Probably, but it escapes me.  It most certainly predates my involvement 
in this project.
> Also, the eth_set_current() checking should IMHO be done  just  once,
> before  we  start  a  network  transfer,  or  when we actually switch
> interfaces, but not for each and every call to NetLoop() ?
>
>   
Maybe, but eth_set_current() is pretty lightweight.  NetLoop is only 
called when we start a network transfer, so this doesn't seem too 
egregious.  It could definitely stand to be refactored.
> Best regards,
>
> Wolfgang Denk
>
>   
regards,
Ben