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Date:   Wed, 17 May 2023 15:20:00 -0700
From:   Peilin Ye <yepeilin.cs@gmail.com>
To:     Vlad Buslov <vladbu@nvidia.com>
Cc:     Jakub Kicinski <kuba@kernel.org>, Jiri Pirko <jiri@resnulli.us>,
        Daniel Borkmann <daniel@iogearbox.net>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        Cong Wang <xiyou.wangcong@gmail.com>,
        Peilin Ye <peilin.ye@bytedance.com>,
        John Fastabend <john.fastabend@gmail.com>,
        Pedro Tammela <pctammela@mojatatu.com>,
        Hillf Danton <hdanton@sina.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, Cong Wang <cong.wang@bytedance.com>
Subject: Re: [PATCH net 6/6] net/sched: qdisc_destroy() old ingress and
 clsact Qdiscs before grafting
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On Wed, May 17, 2023 at 11:48:05AM -0700, Jakub Kicinski wrote:
> On Wed, 17 May 2023 11:49:10 +0300 Vlad Buslov wrote:
> > I wonder if somehow leveraging existing tc_modify_qdisc() 'replay'
> > functionality instead of returning error to the user would be a better
> > approach? Currently the function is replayed when qdisc_create() returns
> > EAGAIN. It should be trivial to do the same for qdisc_graft() result.
>
> Sounds better than returning -EBUSY to the user and expecting them
> to retry, yes.

Thanks for the suggestion, Vlad!  I'll try this in tc_modify_qdisc() and
tc_get_qdisc() (for Qdisc deletion) in v2.

Thanks,
Peilin Ye