On Sat, Jan 27, 2001 at 08:28:05AM +0100, Maciej W. Rozycki wrote:
> > Afaik the only user of MIPS_ATOMIC_SET ever running on Linux/MIPS is the
> > Linuxthreads code you wrote, so no. Aside of that the semantics of this
> > syscall were defined by older MIPS operating systems such as Risc/OS and
> > I think we should follow their example.
>
> I still haven't seen a definite spec for the call.
Sorry, the specs is code and docs I have access to here inside SGI and which
I cannot pass on ...
> Since you suggest the Linuxthreads code is the only user of the code
> (also remember the _test_and_set library function as specified by the ABI),
> we might abandon MIPS_ATOMIC_SET and write a _test_and_set syscall
> instead. No compatibility issues would be involved and the definition is
> clear in the ABI (the library function would become a simple wrapper).
We have an IRIX 5 emulation and if I remember right for IRIX 5
MIPS_ATOMIC_SET is still supported, so we need to also. So I fear we'll
have to keep sysmips. Which still doesn't mean we should come up with
something better.
> I'm still uncertain if wasting a syscall number is that great idea, but
> we would be free from any compatibility problems. And yes, I still think
> an ll/sc emulation could be done independently anyway.
Ralf
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