Re: [RFC V4 2/6] blk-wbt: make wbt pluggable

[Christoph Hellwig]

On Fri, Feb 18, 2022 at 11:41:11AM +0800, Wang Jianchao wrote:
> 
> 
> On 2022/2/17 4:50 下午, Christoph Hellwig wrote:
> >> +struct rq_qos *wbt_rq_qos(struct request_queue *q);
> >>  int wbt_init(struct request_queue *);
> > 
> > 
> > Please move the wb_lat sysfs attribute into blk-wbt.c as well, which
> > removes the need to expose these two functions.
> > 
> 
> Given this patchset:
> (1) Do we need to reserve the wb_lat sysfs when we turn off the wbt ?
> (2) Do we need to disable wbt automatically when switch io scheduler
>     to bfq ? Or just tell the user turn off the wbt by themselves ?

I don't think this needs any changes to what is done there today,
i.e. keep the sysfs attribute around.