From: Andi Kleen <ak@suse.de>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Subject: Re: sched_clock() uses are broken
Date: Sun, 7 May 2006 18:03:28 +0200
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Cc: Russell King <rmk+lkml@arm.linux.org.uk>, Mike Galbraith <efault@gmx.de>,
       Christopher Friesen <cfriesen@nortel.com>, linux-kernel@vger.kernel.org
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On Sunday 07 May 2006 16:04, Nick Piggin wrote:
> Russell King wrote:
> 
> > Also, any comments on update_cpu_clock() and current_sched_time() both
> > appearing to be buggy, or am I barking up the wrong tree with those?
> 
> Can't remember off the top of my head who put those in, sorry.
> 
> Aside from the fact that they appear to be fundamentally buggy anyway
> because we don't require exact ns intervals from sched_clock() at the
> best of times, I think your wrapping fix for them looks correct.

I must say I always hated them because adding code to the context
switch for such an obscure POSIX bu^w"feature" is just a bad idea.
Maybe it would be best to remove it again instead of adding the 
scaling needed to make it actually work

(since we got along with such a broken implementation for so long I 
would guess that nobody uses these timers anyways) 

-Andi

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