Re: [PATCH v2 1/2] block: add BPF kfuncs to read blkcg io.stat

Hi Tejun,

On Tue, Aug 18, 2026 at 07:21:37AM -1000, Tejun Heo wrote:
>Hello,
>
>On Mon, Aug 17, 2026 at 02:42:04PM -0700, Ziyang Men wrote:
>> +/**
>> + * bpf_blkcg_flush_stats - Flush a block cgroup's io statistics
>> + * @cgrp: cgroup to flush
>> + *
>> + * Propagate I/O statistics up the cgroup tree. Root statistics come from
>> + * block devices and include all cgroups' I/O.
>> + */
>> +__bpf_kfunc void bpf_blkcg_flush_stats(struct cgroup *cgrp)
>
>Either @css or @blkcg, probably the latter so that each operation doesn't
>have to verify subsys again. I'd make this and the cpu ppatches into a
>single series. Add blkcg cast there too.

Ok I will add the casts bpf_get_blkcg() and bpf_put_blkcg(), and remove the
check of css->ss in above functoins.

Next submission of this series will be together with the cpu one.

>
>Thanks.
>
>-- 
>tejun

Thanks for your review!

Best,
Ziyang