Re: [PATCH v7 01/15] sched/core: uclamp: Add CPU's clamp buckets refcounting

From: Peter Zijlstra
Date: Wed Mar 13 2019 - 13:22:45 EST


On Wed, Mar 13, 2019 at 04:12:29PM +0000, Patrick Bellasi wrote:
> Yes, the for looks better, but perhaps like that:
>
> unsigned int bucket_id = UCLAMP_BUCKETS;
>
> /*
> * Both min and max clamps are MAX aggregated, thus the topmost
> * bucket with some tasks defines the rq's clamp value.
> */
> for (; bucket_id >= 0; --bucket_id) {

GCC will be clever and figure that unsigned will never be smaller than 0
and turn the above into an infinite loop or something daft.

That is; use 'int', not 'unsigned int' for bucket_id.