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To: Stephen Hemminger <stephen@networkplumber.org>,
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From: Declan Doherty <declan.doherty@intel.com>
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Date: Fri, 6 May 2016 11:32:19 +0100
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Subject: Re: [dpdk-dev] [PATCH 1/5] bonding: replace spinlock with
 read/write lock
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On 05/05/16 18:12, Stephen Hemminger wrote:
> On Thu,  5 May 2016 16:14:56 +0100
> Bernard Iremonger <bernard.iremonger@intel.com> wrote:
>
>> Fixes: a45b288ef21a ("bond: support link status polling")
>> Signed-off-by: Bernard Iremonger <bernard.iremonger@intel.com>
>
> You know an uncontested reader/writer lock is significantly slower
> than a spinlock.
>

As we can have multiple readers of the active slave list / primary 
slave, basically any tx/rx burst call needs to protect against a device 
being removed/closed during it's operation now that we support 
hotplugging, in the worst case this could mean we have 2(rx+tx) * queues 
possibly using the active slave list simultaneously, in that case I 
would have thought that a spinlock would have a much more significant 
affect on performance?