linux-kernel - Re: RCU-Task[-Trace] VS EQS (was Re: [PATCH v3 13/25] context_tracking, rcu: Rename rcu_dynticks_task*() into rcu

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240805090122.GH37996@noisy.programming.kicks-ass.net>
Date: Mon, 5 Aug 2024 11:01:22 +0200
From: Peter Zijlstra <peterz@...radead.org>
To: "Paul E. McKenney" <paulmck@...nel.org>
Cc: Frederic Weisbecker <frederic@...nel.org>,
	Valentin Schneider <vschneid@...hat.com>, rcu@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Neeraj Upadhyay <quic_neeraju@...cinc.com>,
	Joel Fernandes <joel@...lfernandes.org>,
	Josh Triplett <josh@...htriplett.org>,
	Boqun Feng <boqun.feng@...il.com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
	Lai Jiangshan <jiangshanlai@...il.com>,
	Zqiang <qiang.zhang1211@...il.com>
Subject: Re: RCU-Task[-Trace] VS EQS (was Re: [PATCH v3 13/25]
 context_tracking, rcu: Rename rcu_dynticks_task*() into rcu_task*())

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.