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Date: Mon, 27 Jul 2015 18:30:05 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: linux-kernel@vger.kernel.org, mingo@kernel.org
Cc: jasonbaron0@gmail.com, bp@alien8.de, luto@amacapital.net,
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Subject: Re: [RFC][PATCH 5/7] jump_label: Rework update logic
Message-ID: <20150727163005.GP18673@twins.programming.kicks-ass.net>
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On Mon, Jul 27, 2015 at 12:47:14PM +0200, Peter Zijlstra wrote:
> @@ -68,13 +63,8 @@ void static_key_slow_inc(struct static_k
>  		return;
>  
>  	jump_label_lock();
> +	if (atomic_inc_and_test(&key->enabled))

atomic_inc_return() == 1, works _much_ better.

> +		jump_label_update(key);
>  	jump_label_unlock();
>  }