Re: [dpdk-dev] [PATCH 0/2] add support for buffered tx to ethdev

[Stephen Hemminger <stephen@networkplumber.org>]

On Fri, 15 Jan 2016 15:43:56 +0100
Tomasz Kulasek <tomaszx.kulasek@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 in the ethdev library are:
> * 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.
> 
> As well as these, an additional reference callback is provided, which
> frees the packets (as the default callback does), as well as updating a
> user-provided counter, so that the number of dropped packets can be
> tracked.
> 
> The internal buffering of packets for TX in sample apps is no longer
> needed, so this patchset also replaces this code with calls to the new
> rte_eth_tx_buffer* APIs in:

The pipeline code also has its own implementation of this.