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

[Kaz K. <kk...@rr...>]

Paul Mundt <le...@li...> wrote:
> 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.

Looks not so different with atomic.h and I always prefer to follow
the x86 way :-)  But, anyway, either way looks ok.

> 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.

Former, I believe.  It looks that kernel simply ignore such platforms
in full futex support which is required by glibc.  In general, platforms
without ll/sc-like can't use nptl and aren't target of current glibc in
the first place.  SH is an exception in this regard by virtue of gUSA.

Regards,
	kaz