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Date: Tue, 24 Jun 2014 16:07:16 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Bruce Richardson <bruce.richardson@intel.com>
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Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] [RFC PATCH DRAFT 1/2] ethdev: add buffered single
 pkt TX function to API
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On Tue, 24 Jun 2014 23:32:15 +0100
Bruce Richardson <bruce.richardson@intel.com> wrote:

> Many sample apps include internal buffering for single-packet-at-a-time
> operation. Since this is such a common paradigm, this functionality is
> better suited to being inside the core ethdev API.
> The new APIs include three functions:
> * rte_eth_tx_buffer - buffer up a single packet for future transmission
> * rte_eth_tx_buffer_flush - flush any unsent buffered packets
> * rte_eth_tx_buffer_set_err_callback - set up a callback to be called in
>   case transmitting a buffered burst fails. By default, we just free the
>   unsent packets

This must be per-queue to be MP safe.

Internally, we do something similar but it proved to be fastest to
user per-cpu data in some cases.