Re: [PATCH v2 11/13] rcu-tasks: Report stalls during synchronize_srcu() in rcu_tasks_postscan()

[Frederic Weisbecker]

Le Sat, Mar 25, 2023 at 05:33:14PM +0000, Joel Fernandes (Google) a écrit :
> From: Neeraj Upadhyay <quic_neeraju@xxxxxxxxxxx>
> 
> 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@xxxxxxxxxx>
> Link: https://lore.kernel.org/rcu/20230111212736.GA1062057@paulmck-ThinkPad-P17-Gen-1/
> Signed-off-by: Neeraj Upadhyay <quic_neeraju@xxxxxxxxxxx>
> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>

Acked-by: Frederic Weisbecker <frederic@xxxxxxxxxx>