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From:   Yafang Shao <laoar.shao@gmail.com>
Date:   Thu, 25 Jan 2018 23:56:18 +0800
Message-ID: <CALOAHbCpDjivn53-OM2RpOnmm2qFujw23ANnmvCGJvcpnP4DMA@mail.gmail.com>
Subject: Re: [PATCH bpf-next] cgroup: support attaching eBPF programs to
 net_prio cgroup
To:     Tejun Heo <tj@kernel.org>
Cc:     Roman Gushchin <guro@fb.com>, David Miller <davem@davemloft.net>,
        longman@redhat.com, lizefan@huawei.com,
        Johannes Weiner <hannes@cmpxchg.org>,
        Cgroups <cgroups@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Thu, Jan 25, 2018 at 11:50 PM, Tejun Heo <tj@kernel.org> wrote:
> On Thu, Jan 25, 2018 at 11:38:48PM +0800, Yafang Shao wrote:
>> If net_prio is used, we could also use eBPF programs to attach it,
>> because the net_prio cgroup could be got with prioidx in struct
>> sock_cgroup_data.
>> Hence it should not only be limited to cgroup2.
>
> I really don't wanna do this.  This comes with all sorts of reverse
> lookup and naming issues.  In addition, cgroup1 and 2 aren't mutually
> exclusive.  If the use case is on cgroup1 and wants to use cgroup bpf
> programs, just replicate the cgroup2 hierarchy for bpf.  Hierarchy
> replication across different controllers is how most use cgroup1 after
> all.  With recent versions of systemd which defaults to using cgroup2
> for process management, you get the replication for free too.
>

Hi Tejun,

I don't understand what do you mean Hierarchy replication.
Could you pls. show me some examples  ?


Thanks
Yafang