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Date:   Tue, 9 May 2023 13:07:22 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     LKML <linux-kernel@vger.kernel.org>, x86@kernel.org,
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Subject: Re: [patch v3 18/36] [patch V2 18/38] cpu/hotplug: Add CPU state
 tracking and synchronization
Message-ID: <20230509110722.GZ83892@hirez.programming.kicks-ass.net>
References: <20230508181633.089804905@linutronix.de>
 <20230508185218.240871842@linutronix.de>
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On Mon, May 08, 2023 at 09:43:55PM +0200, Thomas Gleixner wrote:

> +static inline void cpuhp_ap_update_sync_state(enum cpuhp_sync_state state)
> +{
> +	atomic_t *st = this_cpu_ptr(&cpuhp_state.ap_sync_state);
> +	int sync = atomic_read(st);
> +
> +	while (!atomic_try_cmpxchg(st, &sync, state));
> +}

Why isn't:

	atomic_set(st, state);

any good?