Re: [RFC V2 5/6] blk-ioprio: make ioprio pluggable and modular

[Bart Van Assche]

On 2/15/22 18:09, Wang Jianchao wrote:
> On 2022/2/16 5:26 上午, Bart Van Assche wrote:
> > On 2/15/22 04:37, Wang Jianchao (Kuaishou) wrote:
> > > diff --git a/block/Makefile b/block/Makefile
> > > index f38eaa612929..f6a3995af285 100644
> > > --- a/block/Makefile
> > > +++ b/block/Makefile
> > > @@ -17,7 +17,8 @@ obj-$(CONFIG_BLK_DEV_BSGLIB)    += bsg-lib.o
> > >    obj-$(CONFIG_BLK_CGROUP)    += blk-cgroup.o
> > >    obj-$(CONFIG_BLK_CGROUP_RWSTAT)    += blk-cgroup-rwstat.o
> > >    obj-$(CONFIG_BLK_DEV_THROTTLING)    += blk-throttle.o
> > > -obj-$(CONFIG_BLK_CGROUP_IOPRIO)    += blk-ioprio.o
> > > +io-prio-y             := blk-ioprio.o
> > > +obj-$(CONFIG_BLK_CGROUP_IOPRIO)    += io-prio.o
> > >    obj-$(CONFIG_BLK_CGROUP_IOLATENCY)    += blk-iolatency.o
> > >    obj-$(CONFIG_BLK_CGROUP_IOCOST)    += blk-iocost.o
> > >    obj-$(CONFIG_MQ_IOSCHED_DEADLINE)    += mq-deadline.o
> >
> > Is the above change really necessary?
>
> Except for making maintaining easier on a running system, removing a
> rqos policy module with cgroup supporting can release a blk-cgroup
> policy slots. As BLKCG_MAX_POLS, the max slots number is fixed now.

It seems like my question was not clear? What I meant is that I think 
that the above changes are not necessary to build blk-ioprio as a kernel 
module.

Thanks,

Bart.