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Date:   Wed, 6 Dec 2023 21:10:22 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Ankur Arora <ankur.a.arora@oracle.com>
Cc:     paulmck@kernel.org, Thomas Gleixner <tglx@linutronix.de>,
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Subject: Re: [RFC PATCH 48/86] rcu: handle quiescent states for
 PREEMPT_RCU=n
Message-ID: <20231206211022.710ada02@gandalf.local.home>
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On Wed, 06 Dec 2023 17:31:30 -0800
Ankur Arora <ankur.a.arora@oracle.com> wrote:

> ---
> diff --git a/include/linux/preempt.h b/include/linux/preempt.h
> index 9aa6358a1a16..d8139cda8814 100644
> --- a/include/linux/preempt.h
> +++ b/include/linux/preempt.h
> @@ -226,9 +226,11 @@ do { \
>  #ifdef CONFIG_PREEMPTION
>  #define preempt_enable() \
>  do { \
>  	barrier(); \
>  	if (unlikely(preempt_count_dec_and_test())) \
>  		__preempt_schedule(); \
> +	else if (unlikely(raw_cpu_read(rcu_data.rcu_urgent_qs))) \

Shouldn't this still have the:

	else if (!IS_ENABLED(CONFIG_PREEMPT_RCU) && \

That is, is it needed when PREEMPT_RCU is set?

-- Steve


> +		rcu_all_qs_check();
>  } while (0)
> 
>  #define preempt_enable_notrace() \