Re: [PATCH v3] drm/i915: Explicitly cast divisor and use div_u64()

[Andi Shyti]

Hi Thorsten,

> diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
> index 025a79fe5920..6ff905d2b78f 100644
> --- a/drivers/gpu/drm/i915/i915_perf.c
> +++ b/drivers/gpu/drm/i915/i915_perf.c
> @@ -4063,17 +4063,13 @@ static int read_properties_unlocked(struct i915_perf *perf,
>  			oa_period = oa_exponent_to_ns(perf, value);
>  
>  			/* This check is primarily to ensure that oa_period <=
> -			 * UINT32_MAX (before passing to do_div which only
> +			 * UINT32_MAX (before passing it to div_u64 which only
>  			 * accepts a u32 denominator), but we can also skip
>  			 * checking anything < 1Hz which implicitly can't be
>  			 * limited via an integer oa_max_sample_rate.
>  			 */
> -			if (oa_period <= NSEC_PER_SEC) {
> -				u64 tmp = NSEC_PER_SEC;
> -				do_div(tmp, oa_period);
> -				oa_freq_hz = tmp;
> -			} else
> -				oa_freq_hz = 0;
> +			oa_freq_hz = oa_period > NSEC_PER_SEC ? 0 :
> +				div_u64(NSEC_PER_SEC, (u32)oa_period);

Thanks for the follow up!

Reviewed-by: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx>

Andi