Date: Wed, 28 Aug 2013 20:54:15 +0100
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>, akpm@linuxfoundation.org,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>, linux-arch@vger.kernel.org,
        Steven Rostedt <srostedt@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: [gcv v3 27/35] arm: Replace __get_cpu_var uses
Message-ID: <20130828195415.GP6617@n2100.arm.linux.org.uk>
References: <20130828193457.140443630@linux.com> <00000140c67834c9-cc2bec76-2d70-48d1-a35b-6e2d5dedf22b-000000@email.amazonses.com>
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On Wed, Aug 28, 2013 at 07:48:23PM +0000, Christoph Lameter wrote:
> 3. Retrieve the content of the current processors instance of a per cpu variable.
> 
> 	DEFINE_PER_CPU(int, u);

Shouldn't this be 'y' ?

> 	int x = __get_cpu_var(y)
> 
>    Converts to
> 
> 	int x = __this_cpu_read(y);
> 
> 
> 4. Retrieve the content of a percpu struct
> 
> 	DEFINE_PER_CPU(struct mystruct, y);
> 	struct mystruct x = __get_cpu_var(y);
> 
>    Converts to
> 
> 	memcpy(this_cpu_ptr(&x), y, sizeof(x));

Are you sure this one's correct?  Isn't 'y' the per-cpu variable?
Even though I don't see any in this patch, it's probably a good thing to
get the patch description correct.

I think you need Will Deacon's ack for this, but I think he's away for
a while.
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