Date: Thu, 7 Jan 2010 11:05:21 -0600 (CST)
From: Christoph Lameter <cl@linux-foundation.org>
To: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
cc: Tejun Heo <tj@kernel.org>, linux-kernel@vger.kernel.org
Subject: Re: [RFC local_t removal V1 0/4] Remove local_t
In-Reply-To: <20100105224516.GA32584@Krystal>
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References: <20100105220417.400092933@quilx.com> <20100105222351.GA29675@Krystal> <alpine.DEB.2.00.1001051629550.9108@router.home> <20100105224516.GA32584@Krystal>
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On Tue, 5 Jan 2010, Mathieu Desnoyers wrote:

> > Volatile is discouraged as far as I can tell.
>
> If you want to ensure that a simple variable assignment or read
> (local_set, local_read) are not performed piecewise by the compiler
> which can cause odd effects when shared with interrupt handlers, this
> will however be necessary.

Piecewise? Assignment of scalars or a pointer is an atomic operation by
default. Lots of things will break if that is not true.
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