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Date: Fri, 15 Dec 2023 14:50:59 -0800
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>, Boqun Feng <boqun.feng@gmail.com>, Daniel Borkmann
 <daniel@iogearbox.net>, Eric Dumazet <edumazet@google.com>, Frederic
 Weisbecker <frederic@kernel.org>, Ingo Molnar <mingo@redhat.com>, Paolo
 Abeni <pabeni@redhat.com>, Peter Zijlstra <peterz@infradead.org>, Thomas
 Gleixner <tglx@linutronix.de>, Waiman Long <longman@redhat.com>, Will
 Deacon <will@kernel.org>
Subject: Re: [PATCH net-next 00/24] locking: Introduce nested-BH locking.
Message-ID: <20231215145059.3b42ee35@kernel.org>
In-Reply-To: <20231215171020.687342-1-bigeasy@linutronix.de>
References: <20231215171020.687342-1-bigeasy@linutronix.de>
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On Fri, 15 Dec 2023 18:07:19 +0100 Sebastian Andrzej Siewior wrote:
> The proposed way out is to introduce explicit per-CPU locks for
> resources which are protected by local_bh_disable() and use those only
> on PREEMPT_RT so there is no additional overhead for !PREEMPT_RT builds.

As I said at LPC, complicating drivers with odd locking constructs
is a no go for me.