From mboxrd@z Thu Jan  1 00:00:00 1970
From: rostedt@goodmis.org (Steven Rostedt)
Date: Thu, 12 Nov 2015 09:47:39 -0500
Subject: [PATCH] sched/rt: hide push_irq_work_func declaration
In-Reply-To: <3810009.VdDTV0h1Qp@wuerfel>
References: <3810009.VdDTV0h1Qp@wuerfel>
Message-ID: <20151112094739.0168e191@gandalf.local.home>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Thu, 12 Nov 2015 15:22:22 +0100
Arnd Bergmann <arnd@arndb.de> wrote:

> The push_irq_work_func() function is conditionally defined only
> when both CONFIG_SMP and HAVE_RT_PUSH_IPI are defined, but the
> forward declaration remains visibile without HAVE_RT_PUSH_IPI,
> causing a gcc warning in ARM64 allnoconfig:
> 
> kernel/sched/rt.c:68:13: warning: 'push_irq_work_func' declared 'static' but never defined [-Wunused-function]
> 
> This changes the code to use the same condition for both the
> declaration and the function definition, which gets rid of the
> warning.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Fixes: b6366f048e0c ("sched/rt: Use IPI to trigger RT task push migration instead of pulling")
> ---
> Found on arm64 allnoconfig
> 
> diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
> index e3cc16312046..ce7b36d6f477 100644
> --- a/kernel/sched/rt.c
> +++ b/kernel/sched/rt.c
> @@ -64,7 +64,7 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
>  	raw_spin_unlock(&rt_b->rt_runtime_lock);
>  }
>  
> -#ifdef CONFIG_SMP
> +#if IS_ENABLED(CONFIG_SMP) && defined(HAVE_RT_PUSH_IPI)

Why IS_ENABLED() and not defined()?

#if defined(CONFIG_SMP) && defined(HAVE_RT_PUSH_IPI)

I thought IS_ENABLED() is used for C code, like:

	if (IS_ENABLED(CONFIG_SMP)) {
		[...]
	}

-- Steve

>  static void push_irq_work_func(struct irq_work *work);
>  #endif
>