Date: Sat, 15 Mar 2008 05:18:24 +0100 (CET)
From: Roman Zippel <zippel@linux-m68k.org>
To: john stultz <johnstul@us.ibm.com>
cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org
Subject: Re: [PATCH 7/8] Remove current_tick_length()
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Hi,

On Fri, 14 Mar 2008, john stultz wrote:

> > Why would someone do something silly like this?
> 
> Its not a huge deal, but we've seen globally scoped timekeeping
> variables misused either accidentally or intentionally. Awhile back ppc
> was corrupting time_offset by using it for a timezone offset value. 
> 
> So I think its a valid maintainability issue.

ppc used to do a whole lot more than that, so I don't think that counts as 
a valid example.
tick_length is overwritten at every timer and modifying it would have 
barely any effect compared to other values which are already exported.

> > > Is there any additional rational for this change?
> > 
> > Useless bloat?
> 
> I agree its a trade off. But do you have performance numbers to make the
> maintainability trade off worth it? (I admit, it is used in the
> timer_interrupt, so it may very well be worth it, but we might want to
> check first).

It depends on the architecture, but it's effects regularly executed code 
and every byte counts.

bye, Roman
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