Re: [PATCH 110/110] lib/vdso: Improve do_hres() and update vdso data unconditionally

[Thomas Gleixner]

On Mon, 21 Oct 2019, Huacai Chen wrote:
> @@ -50,7 +50,7 @@ static int do_hres(const struct vdso_data *vd, clockid_t clk,
>  		cycles = __arch_get_hw_counter(vd->clock_mode);
>  		ns = vdso_ts->nsec;
>  		last = vd->cycle_last;
> -		if (unlikely((s64)cycles < 0))
> +		if (unlikely(cycles == U64_MAX))
>  			return -1;

That used to create worse code than the weird (s64) type cast which has the
same effect. Did you double check that there is no change?

Thanks,

	tglx