Re: 2.6.28-rc4-mmotm1110 - you gotta be kidding me...

[Andrew Morton]

On Mon, 10 Nov 2008 21:55:37 -0500 Valdis.Kletnieks@xxxxxx wrote:

> Somebody's been hitting the phunky pharmaceuticals in the last 4 days,
> because this ball-of-joy snuck into linux-next.patch sometime between
> -mmotm1106 and --mmotm1110.
> 
> Seen in a 'make silentallconfig'
> 
>   Single-depth WCHAN output (SCHED_NO_NO_OMIT_FRAME_POINTER) [Y/n/?] (NEW) ?
> 
>   Calculate simpler /proc/<PID>/wchan values. If this option
>   is disabled then wchan values will recurse back to the
>   caller function. This provides more accurate wchan values,
>   at the expense of slightly more scheduling overhead.

I got lost here.

>   If in doubt, say "Y".
> 
> So if I say 'y', is that a request to disable it, or enable it?  And
> what exactly do I get if I vote *against* 'more accurate wchan values'?
> Do I get everybody having the same wchan pointing somewhere in the
> scheduler code, because that's where __builtin_return_address() points?
> 
> And please - a triple negative in the Kconfig variable name?  This has
> gotta be a winner for poor taste in variable naming...
> 

Even if that is all sorted out, how the heck is anyone to decide
whether or not they need this thing?

Also, if we really really are so wishy-washy indecisive that we need to
make the function optional, it should if at all possible be made
runtime-configurable, not compile-time.

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