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Date: Tue, 14 Jun 2016 22:07:34 +0800
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: Huawei Xie <huawei.xie@intel.com>
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Subject: Re: [dpdk-dev] [PATCH] vhost: remove internal lockless enqueue
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Firstly, it's V2. So, don't forget to add version number and link it to 
the previous version next time.

On Mon, Jun 13, 2016 at 07:52:12PM +0800, Huawei Xie wrote:
> All other DPDK PMDs doesn't support concurrent receiving or sending
> packets to the same queue. The upper application should deal with
> this, normally through queue and core bindings.
> 
> Due to historical reason, vhost internally supports concurrent lockless
> enqueuing packets to the same virtio queue through costly cmpset operation.
> This patch removes this internal lockless implementation and should improve
> performance a bit.
> 
> Luckily DPDK OVS doesn't rely on this behavior.
> 
> Signed-off-by: Huawei Xie <huawei.xie@intel.com>

Applied to dpdk-next-virtio, with the rebase on top of my vhost ABI/API
changes.

FYI, I also renamed the title a bit to "remove concurrent enqueue" as
Thomas mentioned in the last version, that it's confusing to say "remove
lockless" here, since we are actually removing the lock.

Thanks.

	--yliu