Re: [PATCH] net/sched: drr: reseed active class deficit after quantum changes

[Jakub Kicinski]

On Tue,  9 Jun 2026 00:36:18 +0000 Samuel Moelius wrote:
> Subject: [PATCH] net/sched: drr: reseed active class deficit after quantum changes

If the change is not for a serious bug it needs to be generated against
net-next. This was generated against Linus's tree I guess and doesn't
apply to -next.

> Changing the quantum of an active DRR class leaves the old deficit in
> place.  The next scheduling round can therefore use credit accumulated
> under a different quantum.
> 
> This can be observed by making a class active, changing its quantum, and
> then dequeuing with the old deficit still present.
> 
> When an active class quantum changes, reseed its deficit from the new
> quantum so the changed class weight is reflected immediately.

TBH the current implementation is how I would expect DRR to work.
quantum is the "refill" value, it should not reset the state of 
the current round? It wouldn't in an ASIC.
-- 
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