Re: [PATCH 1/4 v3] cgroup: use separate rstat api for bpf programs

[Yosry Ahmed <yosry.ahmed@linux.dev>]

On Tue, Mar 25, 2025 at 11:03:26AM -0700, JP Kobryn wrote:
> On 3/24/25 10:47 AM, Michal Koutný wrote:
> > On Wed, Mar 19, 2025 at 03:21:47PM -0700, JP Kobryn <inwardvessel@gmail.com> wrote:
> > > The rstat updated/flush API functions are exported as kfuncs so bpf
> > > programs can make the same calls that in-kernel code can. Split these API
> > > functions into separate in-kernel and bpf versions. Function signatures
> > > remain unchanged. The kfuncs are named with the prefix "bpf_". This
> > > non-functional change allows for future commits which will modify the
> > > signature of the in-kernel API without impacting bpf call sites. The
> > > implementations of the kfuncs serve as adapters to the in-kernel API.
> > 
> > This made me look up
> > https://docs.kernel.org/bpf/kfuncs.html#bpf-kfunc-lifecycle-expectations
> > 
> > The series reworks existing kfuncs anyway, is it necessary to have the
> > bpf_ versions? The semantics is changed too from base+all subsystems
> > flush to only base flush (bpf_rstat_flush()).
> 
> This patch was done based on some conversation in v2 around what to do
> with the kfuncs (bottom of [0]). It's true the kfunc API deviates from
> flush-specific-subsystem approach. Dropping this patch is fine by me and
> I assume it would be ok with Yosry (based on comments at end of [0]),
> but I'll wait and see if he has any input.

Yeah I am okay with dropping this as well.

> 
> [0] https://lore.kernel.org/all/Z8IIxUdRpqxZyIHO@google.com/