From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiri Pirko <jiri@resnulli.us>
Subject: Re: [RFC PATCH net-next v6 4/4] netvsc: refactor notifier/event
 handling code to use the bypass framework
Date: Wed, 11 Apr 2018 09:53:34 +0200
Message-ID: <20180411075334.GK2028@nanopsycho>
References: <1523386790-12396-1-git-send-email-sridhar.samudrala@intel.com>
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 <20180410142608.50f15b45@xeon-e3>
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Cc: Sridhar Samudrala <sridhar.samudrala@intel.com>, mst@redhat.com,
        davem@davemloft.net, netdev@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        virtio-dev@lists.oasis-open.org, jesse.brandeburg@intel.com,
        alexander.h.duyck@intel.com, kubakici@wp.pl, jasowang@redhat.com,
        loseweigh@gmail.com
To: Stephen Hemminger <stephen@networkplumber.org>
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Tue, Apr 10, 2018 at 11:26:08PM CEST, stephen@networkplumber.org wrote:
>On Tue, 10 Apr 2018 11:59:50 -0700
>Sridhar Samudrala <sridhar.samudrala@intel.com> wrote:
>
>> Use the registration/notification framework supported by the generic
>> bypass infrastructure.
>> 
>> Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
>> ---
>
>Thanks for doing this.  Your current version has couple show stopper
>issues.
>
>First, the slave device is instantly taking over the slave.
>This doesn't allow udev/systemd to do its device rename of the slave
>device. Netvsc uses a delayed work to workaround this.

Wait. Why the fact a device is enslaved has to affect the udev in any
way? If it does, smells like a bug in udev.


>
>Secondly, the select queue needs to call queue selection in VF.
>The bonding/teaming logic doesn't work well for UDP flows.
>Commit b3bf5666a510 ("hv_netvsc: defer queue selection to VF")
>fixed this performance problem.
>
>Lastly, more indirection is bad in current climate.
>
>I am not completely adverse to this but it needs to be fast, simple
>and completely transparent.