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Date: Thu, 12 Apr 2018 10:13:23 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Joe Perches <joe@perches.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Ingo Molnar <mingo@kernel.org>, Len Brown <len.brown@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] checkpatch: Add a --strict test for structs with bool
 member definitions
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On Wed, Apr 11, 2018 at 11:42:20PM -0700, Joe Perches wrote:
> I personally do not find a significant issue with
> uncontrolled sizes of bool in kernel structs as
> all of the kernel structs are transitory and not
> written out to storage.

People that care about cache locality, false sharing and other such
things really care about structure layout.

Growing a structure into another cacheline can be a significant
performance hit -- cache misses hurt.