Re: [PATCH] scheduler: fix x86 regression in native_sched_clock

[Ingo Molnar <mingo@elte.hu>]

* Mark Lord <lkml@rtr.ca> wrote:

> Ingo Molnar wrote:
>> ...
>> thanks. I do get the impression that most of this can/should wait until 
>> 2.6.25. The patches look quite dangerous.
> ..
>
> I confess to not really trying hard to understand everything in this 
> thread, but the implication seems to be that this bug might affect 
> udelay() and possibly jiffies ?

no, it cannot affect jiffies. (jiffies was a red herring all along)

udelay() cannot be affected either - sched_clock() has no effect on 
udelay(). _But_, when there are TSC problems then tsc based udelay() 
suffers too so the phenomenons may _seem_ related.

> If so, then fixing it has to be a *must* for 2.6.24, as otherwise 
> we'll get all sorts of one-in-while odd driver bugs.. like maybe these 
> two for starters:
>
> [Bug 9492] 2.6.24:  false double-clicks from USB mouse
> [Bug 9489] 20000+ wake-ups/second in 2.6.24

iirc these high rate wakeups happened on 2.6.22 too.

	Ingo
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