Date:   Thu, 16 Mar 2023 00:19:19 +0100
From:   Frederic Weisbecker <frederic@kernel.org>
To:     "Joel Fernandes (Google)" <joel@joelfernandes.org>
Cc:     linux-kernel@vger.kernel.org,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Neeraj Upadhyay <quic_neeraju@quicinc.com>,
        Josh Triplett <josh@joshtriplett.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Zqiang <qiang1.zhang@intel.com>, rcu@vger.kernel.org
Subject: Re: [PATCH 4/9] rcu: Register rcu-lazy shrinker only for
 CONFIG_RCU_LAZY=y kernels
Message-ID: <ZBJSd9tJ8RU7er1o@localhost.localdomain>
References: <20230315194349.10798-1-joel@joelfernandes.org>
 <20230315194349.10798-4-joel@joelfernandes.org>
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Le Wed, Mar 15, 2023 at 07:43:44PM +0000, Joel Fernandes (Google) a ?crit :
> From: Zqiang <qiang1.zhang@intel.com>
> 
> The lazy_rcu_shrink_count() shrinker function is registered even in
> kernels built with CONFIG_RCU_LAZY=n, in which case this function
> uselessly consumes cycles learning that no CPU has any lazy callbacks
> queued.
> 
> This commit therefore registers this shrinker function only in the kernels
> built with CONFIG_RCU_LAZY=y, where it might actually do something useful.
> 
> Signed-off-by: Zqiang <qiang1.zhang@intel.com>
> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>

Reviewed-by: Frederic Weisbecker <frederic@kernel.org>