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Date: Thu, 4 Sep 2014 17:40:20 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Catalin Iacob <iacobcatalin@gmail.com>, Dave Jones <davej@redhat.com>,
        Ingo Molnar <mingo@kernel.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [RFC PATCH 3/9] irq_work: Force raised irq work to run on irq
 work interrupt
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On Thu, Sep 04, 2014 at 03:33:40PM +0200, Frederic Weisbecker wrote:
> > Why not something like the below; then it becomes a compile time matter.
> 
> Problem is that some archs only have that information at runtime.
> See x86 for example which tests cpu_has_apic.

So the other archs can still benefit, no? Also, on x86 cpu features can
be used with asm_goto/jump_labels, your approach wrecks that too by
copying it into some static variable, see static_cpu_has().