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Date:   Wed, 4 Oct 2023 15:46:09 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc:     linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Wander Lairson Costa <hawk@kernel.org>
Subject: Re: [PATCH net-next 0/2] net: Use SMP threads for backlog NAPI (or
 optional).
Message-ID: <20231004154609.6007f1a0@kernel.org>
In-Reply-To: <20230929162121.1822900-1-bigeasy@linutronix.de>
References: <20230929162121.1822900-1-bigeasy@linutronix.de>
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On Fri, 29 Sep 2023 18:20:18 +0200 Sebastian Andrzej Siewior wrote:
>    - Patch #2 has been removed. Removing the warning is still an option.
> 
>    - There are two patches in the series:
>      - Patch #1 always creates backlog threads
>      - Patch #2 creates the backlog threads if requested at boot time,
>        mandatory on PREEMPT_RT.
>      So it is either or and I wanted to show how both look like.
> 
>    - The kernel test robot reported a performance regression with
>      loopback (stress-ng --udp X --udp-ops Y) against the RFC version.
>      The regression is now avoided by using local-NAPI if backlog
>      processing is requested on the local CPU.

Not what we asked for, and it doesn't apply.