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Date:   Sun, 26 Mar 2023 21:53:22 +0200
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>,
        Boqun Feng <boqun.feng@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Zqiang <qiang1.zhang@intel.com>, Mark Brown <broonie@kernel.org>,
        rcu@vger.kernel.org
Subject: Re: [PATCH v2 11/13] rcu-tasks: Report stalls during
 synchronize_srcu() in rcu_tasks_postscan()
Message-ID: <ZCCish6dAkiOOZ1Q@localhost.localdomain>
References: <20230325173316.3118674-1-joel@joelfernandes.org>
 <20230325173316.3118674-12-joel@joelfernandes.org>
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Le Sat, Mar 25, 2023 at 05:33:14PM +0000, Joel Fernandes (Google) a ?crit :
> From: Neeraj Upadhyay <quic_neeraju@quicinc.com>
> 
> The call to synchronize_srcu() from rcu_tasks_postscan() can be stalled
> by a task getting stuck in do_exit() between that function's calls to
> exit_tasks_rcu_start() and exit_tasks_rcu_finish().   To ease diagnosis
> of this situation, print a stall warning message every rcu_task_stall_info
> period when rcu_tasks_postscan() is stalled.
> 
> [ paulmck: Adjust to handle CONFIG_SMP=n. ]
> 
> Reported-by: Mark Brown <broonie@kernel.org>
> Link: https://lore.kernel.org/rcu/20230111212736.GA1062057@paulmck-ThinkPad-P17-Gen-1/
> Signed-off-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>

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