Date:   Thu, 16 Mar 2023 02:28:53 +0000
From:   Joel Fernandes <joel@joelfernandes.org>
To:     Frederic Weisbecker <frederic@kernel.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: <20230316022853.GA110573@google.com>
References: <20230315194349.10798-1-joel@joelfernandes.org>
 <20230315194349.10798-4-joel@joelfernandes.org>
 <ZBJSd9tJ8RU7er1o@localhost.localdomain>
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On Thu, Mar 16, 2023 at 12:19:19AM +0100, Frederic Weisbecker wrote:
> 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>

Thanks!

 - Joel