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Subject: Re: [PATCH] kernel/timer.c: using spin_lock_irqsave instead of
 spin_lock + local_irq_save, especially when CONFIG_LOCKDEP not defined
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Chen Gang <gang.chen@asianux.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Date: Thu, 20 Jun 2013 02:12:54 -0700
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On Thu, 2013-06-20 at 16:37 +0800, Chen Gang wrote:

>  	spin_lock_irqsave(&lock, flags);
> 
>  is not semantically the same as
> 
>  	local_irq_save(flags);
>  	spin_lock(&lock);
> 
> It depend on the spin_lock_irqsave() implementation, if the parameters
> has no relation ship with each other, semantically the same.

Of course all implementations must respect the blocks are
totally the same.

Arguing about this is plain silly.

If you found a buggy implementation, please fix it.