2022-06-21 17:39:11

by Abhinav Kumar

[permalink] [raw]
Subject: Re: [PATCH] drm/msm: Use div64_ul instead of do_div



On 4/26/2022 6:21 AM, Wan Jiabing wrote:
> Fix following coccicheck warning:
> drivers/gpu/drm/msm/msm_gpu_devfreq.c:72:1-7: WARNING: do_div() does a 64-by-32 division, please consider using div64_ul instead.
>
> Use div64_ul instead of do_div to avoid a possible truncation.
>
> Signed-off-by: Wan Jiabing <[email protected]>
Reviewed-by: Abhinav Kumar <[email protected]>
> ---
> drivers/gpu/drm/msm/msm_gpu_devfreq.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/msm_gpu_devfreq.c b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
> index d2539ca78c29..c2ea978c8921 100644
> --- a/drivers/gpu/drm/msm/msm_gpu_devfreq.c
> +++ b/drivers/gpu/drm/msm/msm_gpu_devfreq.c
> @@ -69,7 +69,7 @@ static void get_raw_dev_status(struct msm_gpu *gpu,
> df->time = time;
>
> busy_time *= USEC_PER_SEC;
> - do_div(busy_time, sample_rate);
> + busy_time = div64_ul(busy_time, sample_rate);
> if (WARN_ON(busy_time > ~0LU))
> busy_time = ~0LU;
>