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Date: Mon, 5 Aug 2024 11:01:22 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>,
	Valentin Schneider <vschneid@redhat.com>, rcu@vger.kernel.org,
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Subject: Re: RCU-Task[-Trace] VS EQS (was Re: [PATCH v3 13/25]
 context_tracking, rcu: Rename rcu_dynticks_task*() into rcu_task*())
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In-Reply-To: <6c915a8d-983a-4cbb-8d89-01e326a16876@paulmck-laptop>

On Fri, Aug 02, 2024 at 09:32:08PM -0700, Paul E. McKenney wrote:

> Huh.  One reason for the current smp_call_function_single() in
> cpuhp_report_idle_dead() was some ARM32 CPUs that shut down caching on
> their way out.  this made it impossible to use shared-variable-based
> CPU-dead notification.  I wonder if Arnd's deprecation schedule
> for ARM32-based platforms will allow us to go back to shared-memory
> notification, which might make this sort of thing easier.

All those idle paths should be doing ct_cpuidle_enter(), which includes
telling RCU the CPU is going idle, no?

I cleaned all that up a while back.