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Date: Thu, 27 Oct 2016 18:12:20 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Remy Horton <remy.horton@intel.com>
Message-ID: <20161027181220.752e90ea@xeon-e3>
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Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] [RFC PATCH v2 2/3] lib: add bitrate statistics
 library
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On Fri, 28 Oct 2016 09:04:30 +0800
Remy Horton <remy.horton@intel.com> wrote:

> +
> +struct rte_stats_bitrate_s {
> +	uint64_t last_ibytes;
> +	uint64_t last_obytes;
> +	uint64_t peak_ibits;
> +	uint64_t peak_obits;
> +	uint64_t ewma_ibits;
> +	uint64_t ewma_obits;
> +};
> +

Reader/write access of 64 bit values is not safe on 32 bit platforms.
I think you need to add a generation counter (see Linux kernel syncp)
to handle 32 bit architecture. If done correctly, it would be a nop
on 64 bit platforms.