Re: [PATCH bpf-next v11 2/2] selftests/bpf: Add memcg async reclaim test

[Shakeel Butt <shakeel.butt@linux.dev>]

On Tue, Sep 15, 2026 at 08:29:36PM +0800, Hui Zhu wrote:
> From: Hui Zhu <zhuhui@kylinos.cn>
> 
> Add a test for BPF-driven async proactive reclaim: a BPF program
> watches the refault stats of a memory-pressured cgroup and, once they
> grow, reclaims another cgroup from a bpf_wq callback through
> bpf_proactive_reclaim(). Reclaim is verified through the reclaim_calls
> and reclaimed_bytes counters; the workload timings are only logged, as
> they are a benchmark rather than a pass/fail criterion. Setting
> TEST_MEMCG_ASYNC_RECLAIM_BENCH=1 adds a baseline run without the BPF
> program.
> 
> A second test covers a dying target: bpf_cgroup_from_id() keeps
> returning a cgroup until its last reference is dropped, so the program
> checks the css flags and skips reclaim once the target is offlined or
> dying, and the test removes the target while reclaim is in flight and
> verifies that reclaim stops. Each attempt reports its outcome through
> a ringbuf, so the test waits for events rather than polling counters.
> 
> Signed-off-by: Hui Zhu <zhuhui@kylinos.cn>

Comments from bpf-bots seems serious. Let's address those and then I think we
are good with this series.