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Date: Wed, 18 Mar 2026 13:15:52 +0100
From: Frederic Weisbecker <frederic@kernel.org>
To: Joel Fernandes <joelagnelf@nvidia.com>
Cc: linux-kernel@vger.kernel.org, "Paul E. McKenney" <paulmck@kernel.org>,
	Neeraj Upadhyay <neeraj.upadhyay@kernel.org>,
	Josh Triplett <josh@joshtriplett.org>,
	Boqun Feng <boqun@kernel.org>, Uladzislau Rezki <urezki@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Lai Jiangshan <jiangshanlai@gmail.com>,
	Zqiang <qiang.zhang@linux.dev>, Jonathan Corbet <corbet@lwn.net>,
	Shuah Khan <skhan@linuxfoundation.org>, rcu@vger.kernel.org,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	linux-doc@vger.kernel.org
Subject: Re: [PATCH -next v1 10/16] rcu-tasks: Document that RCU Tasks Trace
 grace periods now imply RCU grace periods
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References: <20260317212217.1527644-1-joelagnelf@nvidia.com>
 <20260317212217.1527644-11-joelagnelf@nvidia.com>
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In-Reply-To: <abqGt2CQCfM4PeqK@localhost.localdomain>

Le Wed, Mar 18, 2026 at 12:04:23PM +0100, Frederic Weisbecker a écrit :
> Le Tue, Mar 17, 2026 at 05:22:11PM -0400, Joel Fernandes a écrit :
> > From: "Paul E. McKenney" <paulmck@kernel.org>
> > 
> > Now that RCU Tasks Trace is implemented in terms of SRCU-fast, the fact
> > that each SRCU-fast grace period implies at least two RCU grace periods
> 
> two or one?
> 
> AFAIU srcu_readers_active_idx_check() it's only one?

But as Paul just told me offline, we flip the idx so it's two. Sorry for the noise.

Thanks.

-- 
Frederic Weisbecker
SUSE Labs