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Subject: Re: [PATCH 4/4] hotplug, powerpc, x86: Remove
 cpu_hotplug_driver_lock()
From: Toshi Kani <toshi.kani@hp.com>
To: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Date: Mon, 19 Aug 2013 09:23:22 -0600
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On Mon, 2013-08-19 at 10:20 -0500, Nathan Fontenot wrote:
> On 08/17/2013 02:46 PM, Toshi Kani wrote:
> > cpu_hotplug_driver_lock() serializes CPU online/offline operations
> > when ARCH_CPU_PROBE_RELEASE is set.  This lock interface is no longer
> > necessary with the following reason:
> > 
> >  - lock_device_hotplug() now protects CPU online/offline operations,
> >    including the probe & release interfaces enabled by
> >    ARCH_CPU_PROBE_RELEASE.  The use of cpu_hotplug_driver_lock() is
> >    redundant.
> >  - cpu_hotplug_driver_lock() is only valid when ARCH_CPU_PROBE_RELEASE
> >    is defined, which is misleading and is only enabled on powerpc.
> > 
> > This patch removes the cpu_hotplug_driver_lock() interface.  As
> > a result, ARCH_CPU_PROBE_RELEASE only enables / disables the cpu
> > probe & release interface as intended.  There is no functional change
> > in this patch.
> > 
> > Signed-off-by: Toshi Kani <toshi.kani@hp.com>
> 
> Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>

Thanks Nathan!
-Toshi