From: Oliver Neukum <oliver@neukum.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH 1/19] MUTEX: Introduce simple mutex implementation
Date: Tue, 13 Dec 2005 14:24:08 +0100
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Am Dienstag, 13. Dezember 2005 14:09 schrieb Alan Cox:
> On Maw, 2005-12-13 at 13:47 +0100, Oliver Neukum wrote:
> > > spinlock to do the cmpxchg. This means that there wont be one single 
> > > global spinlock to emulate cmpxchg, but the mutex's own spinlock can be 
> > > used for it.
> > 
> > Can't you use the pointer as a hash input?
> 
> Some platforms already do this for certain sets of operations like
> atomic_t. The downside however is that you no longer control the lock
> contention or cache line bouncing. It becomes a question of luck rather
> than science as to how well it scales.

On the other hand you don't control cache eviction either, do you?

	Regards
		Oliver
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