[RFC PATCH v3 15/15] powerpc/kernel: Do not inconditionally save non volatile registers on system call

[Nicholas Piggin]

Christophe Leroy's on April 7, 2020 4:16 am:
> +	ret = syscall_exit_prepare_end(ret, regs, ti_flags);
> +	if (unlikely(ret & 0x80000000)) {
> +		ret &= ~0x80000000;

We could just add our own set of defines for these, there's no real
reason to use _TIF_RESTOREALL as I had.

Thanks,
Nick