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Date:   Sun, 2 Oct 2022 17:57:25 +0200
From:   Frederic Weisbecker <frederic@kernel.org>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     rcu@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel-team@fb.com, rostedt@goodmis.org,
        Randy Dunlap <rdunlap@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        John Ogness <john.ogness@linutronix.de>,
        Petr Mladek <pmladek@suse.com>
Subject: Re: [PATCH RFC v2 rcu 2/8] srcu: Create an srcu_read_lock_nmisafe()
 and srcu_read_unlock_nmisafe()
Message-ID: <20221002155725.GC292620@lothringen>
References: <20220929180714.GA2874192@paulmck-ThinkPad-P17-Gen-1>
 <20220929180731.2875722-2-paulmck@kernel.org>
 <20221002155516.GB292620@lothringen>
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On Sun, Oct 02, 2022 at 05:55:16PM +0200, Frederic Weisbecker wrote:
> On Thu, Sep 29, 2022 at 11:07:25AM -0700, Paul E. McKenney wrote:
> > @@ -1090,7 +1121,7 @@ static unsigned long srcu_gp_start_if_needed(struct srcu_struct *ssp,
> >  	int ss_state;
> >  
> >  	check_init_srcu_struct(ssp);
> > -	idx = srcu_read_lock(ssp);
> > +	idx = __srcu_read_lock_nmisafe(ssp);
> 
> Why do we need to force the atomic based version here (even if
> CONFIG_NEED_SRCU_NMI_SAFE=y)?

...even if CONFIG_NEED_SRCU_NMI_SAFE=n that is...