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Date:   Fri, 8 Apr 2022 17:42:45 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Kalesh Singh <kaleshsingh@google.com>
Cc:     paulmck@kernel.org, Joel Fernandes <joel@joelfernandes.org>,
        Suren Baghdasaryan <surenb@google.com>,
        kernel-team <kernel-team@android.com>, Tejun Heo <tj@kernel.org>,
        Tim Murray <timmurray@google.com>, Wei Wang <wvw@google.com>,
        Kyle Lin <kylelin@google.com>,
        Chunwei Lu <chunweilu@google.com>,
        Lulu Wang <luluw@google.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Neeraj Upadhyay <quic_neeraju@quicinc.com>,
        Josh Triplett <josh@joshtriplett.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        rcu <rcu@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] EXP rcu: Move expedited grace period (GP) work to RT
 kthread_worker
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On Fri, 8 Apr 2022 10:53:53 -0700
Kalesh Singh <kaleshsingh@google.com> wrote:

> If PREEMT_RT systems don’t disable expedited grace periods, we can
> remove default off for those. Steve?

Yep, commit 36221e109eb20 ("rcu: Enable rcu_normal_after_boot
unconditionally for RT") is still there.

OK, that explains it. I missed that change, so I didn't see the relation to
PREEMPT_RT. It wasn't described in the change log nor was there any
comment in the kconfig to say why it was special. Perhaps that should be
added for those that don't know all this tribal knowledge ;-)

-- Steve