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Subject: Re: [PATCH RFC tip/core/rcu 11/11] rcu: move TREE_RCU from softirq
 to kthread
From: Peter Zijlstra <peterz@infradead.org>
To: Christoph Lameter <cl@linux.com>
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On Wed, 2011-02-23 at 13:19 -0600, Christoph Lameter wrote:

> this_cpu_inc is already percpu atomic. On x86 it is an instruction that
> cannot be interrupted nor preempted while in progress.

On x86, yes, but is this true for all architectures? I guess the
fallback is implemented with local_irq_disable() which might be good
enough for some but not for NMI usage.
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