From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bruce Richardson <bruce.richardson@intel.com>
Subject: Re: [PATCH v3 1/3] ring: read tail using atomic load
Date: Mon, 8 Oct 2018 15:43:49 +0100
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Cc: Jerin Jacob <jerin.jacob@caviumnetworks.com>,
 "dev@dpdk.org" <dev@dpdk.org>,
 Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>,
 "Ananyev, Konstantin" <konstantin.ananyev@intel.com>,
 "Gavin Hu (Arm Technology China)" <Gavin.Hu@arm.com>,
 Steve Capper <Steve.Capper@arm.com>, nd <nd@arm.com>,
 "stable@dpdk.org" <stable@dpdk.org>
To: Ola Liljedahl <Ola.Liljedahl@arm.com>
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On Mon, Oct 08, 2018 at 09:22:05AM +0000, Ola Liljedahl wrote:
<snip> 
> "* multi-producer safe lock-free ring buffer enqueue"
> The comment is also wrong. This design is not lock-free, how could it be when there is spinning
> (waiting) for other threads in the code? If a thread must wait for other threads, then by definition
> the design is blocking.
>
My understanding is that the code is lock-free but not wait-free, though
I'm not an expert in this area.

/Bruce