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Date: Fri, 27 Sep 2013 16:26:05 +0200
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH] checkpatch: Make the memory barrier test noisier
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To: Joe Perches <joe@perches.com>
Cc: Ingo Molnar <mingo@kernel.org>, Tim Chen <tim.c.chen@linux.intel.com>, Jason Low <jason.low2@hp.com>, Davidlohr Bueso <davidlohr@hp.com>, Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@linux-foundation.org>, Andrea Arcangeli <aarcange@redhat.com>, Alex Shi <alex.shi@linaro.org>, Andi Kleen <andi@firstfloor.org>, Michel Lespinasse <walken@google.com>, Davidlohr Bueso <davidlohr.bueso@hp.com>, Matthew R Wilcox <matthew.r.wilcox@intel.com>, Dave Hansen <dave.hansen@intel.com>, Rik van Riel <riel@redhat.com>, Peter Hurley <peter@hurleysoftware.com>, linux-kernel@vger.kernel.org, linux-mm <linux-mm@kvack.org>

On Fri, Sep 27, 2013 at 07:14:17AM -0700, Joe Perches wrote:
> Peter Zijlstra prefers that comments be required near uses
> of memory barriers.
> 
> Change the message level for memory barrier uses from a
> --strict test only to a normal WARN so it's always emitted.
> 
> This might produce false positives around insertions of
> memory barriers when a comment is outside the patch context
> block.

One would argue that in that case they're too far away in any case :-)

> And checkpatch is still stupid, it only looks for existence
> of any comment, not at the comment content.

Could we try and alleviate this by giving a slightly more verbose
warning?

Maybe something like:

 memory barrier without comment; please refer to the pairing barrier and
 describe the ordering requirements.

> Suggested-by: Peter Zijlstra <peterz@infradead.org>
> Signed-off-by: Joe Perches <joe@perches.com>

Acked-by: Peter Zijlstra <peterz@infradead.org>

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