On Tue, Mar 04, 2025 at 02:21:27PM -0500, Steven Rostedt wrote:
On Mon, 24 Feb 2025 19:55:11 -0800 Boqun Feng boqun.feng@gmail.com wrote:
From: Ankur Arora ankur.a.arora@oracle.com
To reduce RCU noise for nohz_full configurations, osnoise depends on cond_resched() providing quiescent states for PREEMPT_RCU=n configurations. For PREEMPT_RCU=y configurations -- where cond_resched() is a stub -- we do this by directly calling rcu_momentary_eqs().
With (PREEMPT_LAZY=y, PREEMPT_DYNAMIC=n), however, we have a configuration with (PREEMPTION=y, PREEMPT_RCU=n) where neither of the above can help.
Handle that by providing an explicit quiescent state here for all configurations.
As mentioned above this is not needed for non-stubbed cond_resched(), but, providing a quiescent state here just pulls in one that a future cond_resched() would provide, so doesn't cause any extra work for this configuration.
Cc: Paul E. McKenney paulmck@kernel.org Cc: Daniel Bristot de Oliveira bristot@kernel.org Cc: Steven Rostedt rostedt@goodmis.org
Acked-by: Steven Rostedt (Google) rostedt@goodmis.org
Applied, thanks!
Regards, Boqun
-- Steve
Suggested-by: Paul E. McKenney paulmck@kernel.org Acked-by: Daniel Bristot de Oliveira bristot@kernel.org Signed-off-by: Ankur Arora ankur.a.arora@oracle.com Reviewed-by: Frederic Weisbecker frederic@kernel.org Signed-off-by: Paul E. McKenney paulmck@kernel.org Signed-off-by: Boqun Feng boqun.feng@gmail.com