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

[Ingo Molnar <mingo@elte.hu>]

* Christoph Hellwig <hch@infradead.org> wrote:

> On Tue, Dec 13, 2005 at 08:54:41AM +0100, Ingo Molnar wrote:
> > - i did not touch the 'struct semaphore' namespace, but introduced a
> >   'struct compat_semaphore'.
> 
> Because it's totally braindead.  Your compat_semaphore is a real 
> semaphore and your semaphore is a mutex.  So name them as such.

well, i had the choice between a 30K patch, a 300K patch and a 3000K 
patch. I went for the 30K patch ;-)

> > - i introduced a 'type-sensitive' macro wrapper that switches down() 
> >   (and the other APIs) to either to the assembly variant (if the 
> >   variable's type is struct compat_semaphore), or switches it to the new 
> >   generic mutex (if the type is struct semaphore), at build-time. There 
> >   is no runtime overhead due to this build-time-switching.
> 
> And this one is probably is a great help to win the obsfucated C 
> contests, but otherwise just harmfull.

i never found it to be harmful in any way, and we've now got a year of 
experience with them. Could you elaborate?

	Ingo
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