From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bruce Richardson <bruce.richardson@intel.com>
Subject: Re: [PATCH v2] net/i40e: fix Rx instability with vector
 mode
Date: Fri, 26 Oct 2018 12:11:37 +0100
Message-ID: <20181026111136.GD14620@bricha3-MOBL.ger.corp.intel.com>
References: <1540453252-128654-1-git-send-email-beilei.xing@intel.com>
 <1540535607-115720-1-git-send-email-beilei.xing@intel.com>
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Cc: qi.z.zhang@intel.com, dev@dpdk.org, stable@dpdk.org
To: Beilei Xing <beilei.xing@intel.com>
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On Fri, Oct 26, 2018 at 02:33:27PM +0800, Beilei Xing wrote:
> Previously, there is instability during vector Rx if descriptor
> number is not power of 2, e.g. process hang and some Rx packets
> are unexpectedly empty. That's because vector Rx mode assumes Rx
> descriptor number is power of 2 when doing bit mask.
> This patch allows vector mode only when the number of Rx descriptor
> is power of 2.
> 
> Fixes: 8e109464c022 ("i40e: allow vector Rx and Tx usage")
> Fixes: a3c83a2527e1 ("net/i40e: enable runtime queue setup")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Beilei Xing <beilei.xing@intel.com>
> ---
> 
Do we not limit our descriptor ring sizes to powers of two anyway? Is there
a real need for non-power-of-2 ring sizes?