Re: Give a functional include/asm-sh/futex.h

[Paul M. <le...@li...>]

On Mon, Jun 18, 2007 at 10:11:47AM +0900, Kaz Kojima wrote:
> Paul Mundt <le...@li...> wrote:
> > Hmm.. this all looks terribly generic, if glibc requires the generic
> > implementation to be extended, perhaps this change should be made against
> > asm-generic/futex.h instead?
> 
> Perhaps if local_irq_* are removed, as I can't find any use of
> them in asm-generic/*.h.  It seems to me that the situation is
> quite similar to atomic.h.  So asm-sh/futex.h which includes
> asm-sh/futex-irq.h and asm-sh/futex-llsc.h selectively might
> be a way to go, though I have no strong opinion.
> 
Yes, but I'm rather concerned about the size, perhaps we should
and move it out-of-line and inline the op handlers?

If we just have a set of atomic_futex_op_xxx() ops that correspond to
each FUTEX_OP_xxx that are inlined in futex.h (FR-V seems to do this
already, in arch/frv/kernel/futex.c), futex_atomic_op_inuser() can be
brought out-of-line without any trouble, and we can bury all of the
local_irq_xxx() mess in the futex op itself.

Also, is futex_atomic_cmpxchg_inatomic() required, or should this simply
be a -ENOSYS if we don't have ll/sc methods? It seems like kernel/futex.c
handles the -ENOSYS case ok, and other platforms do return this way.