Re: [RFC] unify semaphore implementations

Trond Myklebust
2005-04-29T00:42:38Z

to den 28.04.2005 Klokka 23:40 (+0100) skreiv Russell King:
> On Thu, Apr 28, 2005 at 02:29:26PM -0400, Benjamin LaHaise wrote:
> > Please review the following series of patches for unifying the
> > semaphore implementation across all architectures (not posted as
> > they're about 350K), as they have only been tested on x86-64. The
> > code generated is functionally identical to the earlier i386
> > variant, but since gcc has no way of taking condition codes as
> > results, there are two additional instructions inserted from the
> > use of generic atomic operations. All told the >6000 lines of code
> > deleted makes for a much easier job for subsequent patches changing
> > semaphore functionality. Cheers,
>
> I'm not sure why we're doing this, apart from a desire to unify stuff.

It started from a desire to extend the existing implementations to
support new features such as asynchronous notification. Currently that
sort of thing is impossible unless your developer-super-powers include
the ability to herd 24 different subsystem maintainers into working
together on a solution.

In other words, the main drive is the desire to make it maintainable.

Cheers,
Trond
--
Trond Myklebust <trond.myklebust@fys.uio.no>