From mboxrd@z Thu Jan  1 00:00:00 1970
From: Song Liu <songliubraving@fb.com>
Subject: Re: pegged softirq and NAPI race (?)
Date: Tue, 18 Sep 2018 21:55:58 +0000
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Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        Alexei Starovoitov <ast@fb.com>,
        netdev <netdev@vger.kernel.org>,
        Alexander Duyck <alexander.h.duyck@intel.com>,
        "michael.chan@broadcom.com" <michael.chan@broadcom.com>,
        Kernel Team <Kernel-team@fb.com>
To: Eric Dumazet <edumazet@google.com>
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> On Sep 18, 2018, at 2:46 PM, Eric Dumazet <edumazet@google.com> wrote:
>=20
> On Tue, Sep 18, 2018 at 2:41 PM Song Liu <songliubraving@fb.com> wrote:
>>=20
>>=20
>>=20
>>>=20
>> I would submit the patch if Eric prefer not to. :)
>=20
>=20
> Hmmm.... maybe the bug is really in ixgbe_netpoll()
>=20
> This whole ndo_poll_controller() stuff  is crazy.
>=20
> All sane implementations should only call napi_schedule()

Current implement is about identical to napi_schedule_irqoff(). Do=20
we really need napi_schedule() instead?

On the other hand, I think we should check napi_complete_done() in
ixgbe_poll() anyway.=20

Song