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Date:   Wed, 2 Nov 2022 11:32:37 -0700
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Uladzislau Rezki <urezki@gmail.com>
Cc:     Joel Fernandes <joel@joelfernandes.org>, rcu@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC] rcu/kfree: Do not request RCU when not needed
Message-ID: <20221102183237.GO5600@paulmck-ThinkPad-P17-Gen-1>
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On Wed, Nov 02, 2022 at 06:30:24PM +0100, Uladzislau Rezki wrote:
> > 
> > to wait for a GP. Or if the poll_state_synchronize_rcu(oldstate)) != 0
> > queue_rcu_work().
> > 
> A small fix. If poll_state_synchronize_rcu(oldstate)) == 0 then
> queue_rcu_work() since a GP is still in progress.

Both get_state_synchronize_rcu() and poll_state_synchronize_rcu()
may be invoked from interrupt handlers.  And from NMI handlers,
for that matter.

							Thanx, Paul