From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: [PATCH] ethdev: add field for device data per process
Date: Thu, 4 Oct 2018 12:31:34 +0100
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References: <1538047596-23954-1-git-send-email-alejandro.lucero@netronome.com>
 <256449070.EJcjglVyyx@xps>
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Cc: dev@dpdk.org, rasland@mellanox.com
To: Thomas Monjalon <thomas@monjalon.net>,
 Alejandro Lucero <alejandro.lucero@netronome.com>, arybchenko@solarflare.com
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On 10/3/2018 9:44 PM, Thomas Monjalon wrote:
> + Cc more people
> 
> 27/09/2018 13:26, Alejandro Lucero:
>> Primary and secondary processes share a per-device private data. With
>> current design it is not possible to have data per-device per-process.
>> This is required for handling properly the CPP interface inside the NFP
>> PMD with multiprocess support.
>>
>> There is also at least another PMD driver, tap, with similar
>> requirements for per-process device data.
> 
> Yes, it is required to fix tap PMD for multi-process usage.
> 
> I am in favor of accepting this change in 18.11.

+1

> 
> [...]
>> @@ -539,7 +539,13 @@ struct rte_eth_dev {
>>  	eth_rx_burst_t rx_pkt_burst; /**< Pointer to PMD receive function. */
>>  	eth_tx_burst_t tx_pkt_burst; /**< Pointer to PMD transmit function. */
>>  	eth_tx_prep_t tx_pkt_prepare; /**< Pointer to PMD transmit prepare function. */
>> -	struct rte_eth_dev_data *data;  /**< Pointer to device data */
>> +	/**
>> +	 * Next two fields are per-device data but *data is shared between
> 
> All fields in rte_eth_dev are per-device.
> 
>> +	 * primary and secondary processes and *process_private is per-process
>> +	 * private.
>> +	 */
>> +	struct rte_eth_dev_data *data;  /**< Pointer to device data. */
>> +	void *process_private; /**< Pointer to per-process device data. */
> 
> We could explain here that this memory is allocated by the PMD.
> 
>