Re: [PATCH 1/19] MUTEX: Introduce simple mutex implementation

Oliver Neukum
2005-12-13T13:23:46Z

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