[dpdk-dev,v2] ethdev: Rename RX/TX enable queue field for queue start and stop

  Update comments for the field start_rx_per_q for better readability.
Rename the field name to rx_enable_queue for better readability too.
Accordingly Update its reference in sample vhost.

Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
---
 examples/vhost/main.c             |  4 ++--
 lib/librte_ether/rte_ethdev.h     | 16 ++++++++++++++--
 lib/librte_pmd_ixgbe/ixgbe_rxtx.c |  8 ++++----
 lib/librte_pmd_ixgbe/ixgbe_rxtx.h |  4 ++--
 4 files changed, 22 insertions(+), 10 deletions(-)
  

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Ouyang Changchun
> Sent: Wednesday, July 23, 2014 12:48 PM
> To: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH v2] ethdev: Rename RX/TX enable queue field
> for queue start and stop
> 
> Update comments for the field start_rx_per_q for better readability.
> Rename the field name to rx_enable_queue for better readability too.
> Accordingly Update its reference in sample vhost.
> 
> Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>


Acked-by Chen Jing (Mark) <jing.d.chen@intel.com>

> ---
>  examples/vhost/main.c             |  4 ++--
>  lib/librte_ether/rte_ethdev.h     | 16 ++++++++++++++--
>  lib/librte_pmd_ixgbe/ixgbe_rxtx.c |  8 ++++----
>  lib/librte_pmd_ixgbe/ixgbe_rxtx.h |  4 ++--
>  4 files changed, 22 insertions(+), 10 deletions(-)
> 
> diff --git a/examples/vhost/main.c b/examples/vhost/main.c
> index 193aa25..2eea431 100644
> --- a/examples/vhost/main.c
> +++ b/examples/vhost/main.c
> @@ -2984,9 +2984,9 @@ MAIN(int argc, char *argv[])
>  		char pool_name[RTE_MEMPOOL_NAMESIZE];
>  		char ring_name[RTE_MEMPOOL_NAMESIZE];
> 
> -		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
> +		rx_conf_default.rx_enable_queue = (uint8_t)zero_copy;
>  		rx_conf_default.rx_drop_en = 0;
> -		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
> +		tx_conf_default.tx_enable_queue = (uint8_t)zero_copy;
>  		nb_mbuf = num_rx_descriptor
>  			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
>  			+ num_switching_cores * MAX_PKT_BURST;
> diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
> index 50df654..ba439f6 100644
> --- a/lib/librte_ether/rte_ethdev.h
> +++ b/lib/librte_ether/rte_ethdev.h
> @@ -604,7 +604,16 @@ struct rte_eth_rxconf {
>  	struct rte_eth_thresh rx_thresh; /**< RX ring threshold registers. */
>  	uint16_t rx_free_thresh; /**< Drives the freeing of RX descriptors.
> */
>  	uint8_t rx_drop_en; /**< Drop packets if no descriptors are available.
> */
> -	uint8_t start_rx_per_q; /**< start rx per queue. */
> +	/**< If rx_enable_queue is true, rte_eth_dev_rx_queue_start
> should be
> +		invocated to start RX for one queue after rte_eth_dev_start
> is
> +		invocated, and rte_eth_dev_rx_queue_start instead of
> +		rte_eth_dev_start is responsible for allocating mbuf from
> +		mempool and setup the DMA physical address. It is useful in
> +		such scenario: buffer address is not available at the point of
> +		rte_eth_dev_start's invocating but available later, e.g. in
> +		VHOST zero copy case, the buffer address used to setup
> DMA
> +		address is available only after one VM(guest) startup. */
> +	uint8_t rx_enable_queue;
>  };
> 
>  #define ETH_TXQ_FLAGS_NOMULTSEGS 0x0001 /**< nb_segs=1 for all
> mbufs */
> @@ -625,7 +634,10 @@ struct rte_eth_txconf {
>  	uint16_t tx_rs_thresh; /**< Drives the setting of RS bit on TXDs. */
>  	uint16_t tx_free_thresh; /**< Drives the freeing of TX buffers. */
>  	uint32_t txq_flags; /**< Set flags for the Tx queue */
> -	uint8_t start_tx_per_q; /**< start tx per queue. */
> +	/**< If tx_enable_queue is true, rte_eth_dev_tx_queue_start must
> be
> +		invocated to start TX for one queue after rte_eth_dev_start
> is
> +		invocated. Refer to start_rx_per_q for the use case. */
> +	uint8_t tx_enable_queue;
>  };
> 
>  /**
> diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
> b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
> index dfc2076..2872fad 100644
> --- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
> +++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
> @@ -1846,7 +1846,7 @@ ixgbe_dev_tx_queue_setup(struct rte_eth_dev
> *dev,
>  	txq->port_id = dev->data->port_id;
>  	txq->txq_flags = tx_conf->txq_flags;
>  	txq->ops = &def_txq_ops;
> -	txq->start_tx_per_q = tx_conf->start_tx_per_q;
> +	txq->tx_enable_queue = tx_conf->tx_enable_queue;
> 
>  	/*
>  	 * Modification to set VFTDT for virtual function if vf is detected
> @@ -2091,7 +2091,7 @@ ixgbe_dev_rx_queue_setup(struct rte_eth_dev
> *dev,
>  	rxq->crc_len = (uint8_t) ((dev->data-
> >dev_conf.rxmode.hw_strip_crc) ?
>  							0 : ETHER_CRC_LEN);
>  	rxq->drop_en = rx_conf->rx_drop_en;
> -	rxq->start_rx_per_q = rx_conf->start_rx_per_q;
> +	rxq->rx_enable_queue = rx_conf->rx_enable_queue;
> 
>  	/*
>  	 * Allocate RX ring hardware descriptors. A memzone large enough to
> @@ -3652,13 +3652,13 @@ ixgbe_dev_rxtx_start(struct rte_eth_dev *dev)
> 
>  	for (i = 0; i < dev->data->nb_tx_queues; i++) {
>  		txq = dev->data->tx_queues[i];
> -		if (!txq->start_tx_per_q)
> +		if (!txq->tx_enable_queue)
>  			ixgbe_dev_tx_queue_start(dev, i);
>  	}
> 
>  	for (i = 0; i < dev->data->nb_rx_queues; i++) {
>  		rxq = dev->data->rx_queues[i];
> -		if (!rxq->start_rx_per_q)
> +		if (!rxq->rx_enable_queue)
>  			ixgbe_dev_rx_queue_start(dev, i);
>  	}
> 
> diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
> b/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
> index 64c0695..d6d856e 100644
> --- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
> +++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
> @@ -135,7 +135,7 @@ struct igb_rx_queue {
>  	uint8_t             port_id;  /**< Device port identifier. */
>  	uint8_t             crc_len;  /**< 0 if CRC stripped, 4 otherwise. */
>  	uint8_t             drop_en;  /**< If not 0, set SRRCTL.Drop_En. */
> -	uint8_t             start_rx_per_q;
> +	uint8_t             rx_enable_queue;
>  #ifdef RTE_LIBRTE_IXGBE_RX_ALLOW_BULK_ALLOC
>  	/** need to alloc dummy mbuf, for wraparound when scanning hw
> ring */
>  	struct rte_mbuf fake_mbuf;
> @@ -200,7 +200,7 @@ struct igb_tx_queue {
>  	/** Hardware context0 history. */
>  	struct ixgbe_advctx_info ctx_cache[IXGBE_CTX_NUM];
>  	struct ixgbe_txq_ops *ops;          /**< txq ops */
> -	uint8_t             start_tx_per_q;
> +	uint8_t             tx_enable_queue;
>  };
> 
>  struct ixgbe_txq_ops {
> --
> 1.8.4.2
  

Hi Ouyang,

2014-07-23 12:48, Ouyang Changchun:
> Update comments for the field start_rx_per_q for better readability.
> Rename the field name to rx_enable_queue for better readability too.
> Accordingly Update its reference in sample vhost.

> -	uint8_t start_rx_per_q; /**< start rx per queue. */
> +	/**< If rx_enable_queue is true, rte_eth_dev_rx_queue_start should be
> +		invocated to start RX for one queue after rte_eth_dev_start is
> +		invocated, and rte_eth_dev_rx_queue_start instead of
> +		rte_eth_dev_start is responsible for allocating mbuf from
> +		mempool and setup the DMA physical address. It is useful in
> +		such scenario: buffer address is not available at the point of
> +		rte_eth_dev_start's invocating but available later, e.g. in
> +		VHOST zero copy case, the buffer address used to setup DMA
> +		address is available only after one VM(guest) startup. */
> +	uint8_t rx_enable_queue;
>  };

I have many comments here.

The doxygen comment /**< must be used only after the symbol you are
commenting:
	http://doxygen.org/manual/docblocks.html#memberdoc

The comment is too long.
The use case would be in the manual, not in doxygen.
The comment about rte_eth_dev_rx_queue_start would be in the doxygen
comment of rte_eth_dev_rx_queue_start.

When this variable is set, it doesn't enable anything. It only disables
the queue when doing a global start. Its name should be rx_deferred_start.
All fields of this structure are about one queue, so the "queue" word is
not needed.

> -	uint8_t start_tx_per_q; /**< start tx per queue. */
> +	/**< If tx_enable_queue is true, rte_eth_dev_tx_queue_start must be
> +		invocated to start TX for one queue after rte_eth_dev_start is
> +		invocated. Refer to start_rx_per_q for the use case. */
> +	uint8_t tx_enable_queue;
>  };

You refer to the old name (start_rx_per_q).
By the way, a one line description (without referral) for both fields should
be enough. Something like "do not start with rte_eth_dev_start()".

> @@ -3652,13 +3652,13 @@ ixgbe_dev_rxtx_start(struct rte_eth_dev *dev)
>  
>  	for (i = 0; i < dev->data->nb_tx_queues; i++) {
>  		txq = dev->data->tx_queues[i];
> -		if (!txq->start_tx_per_q)
> +		if (!txq->tx_enable_queue)
>  			ixgbe_dev_tx_queue_start(dev, i);
>  	}

Here it's clear that this field is about disabling start.

Please rework this patch and update i40e accordingly.
Thanks
  

Hi Thomas,

Thanks very much for your comments!
I will rework this patch and also update for i40e.

Thanks and best regards,
Changchun


> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> Sent: Thursday, September 25, 2014 5:31 PM
> To: Ouyang, Changchun
> Cc: dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v2] ethdev: Rename RX/TX enable queue
> field for queue start and stop
> 
> Hi Ouyang,
> 
> 2014-07-23 12:48, Ouyang Changchun:
> > Update comments for the field start_rx_per_q for better readability.
> > Rename the field name to rx_enable_queue for better readability too.
> > Accordingly Update its reference in sample vhost.
> 
> > -	uint8_t start_rx_per_q; /**< start rx per queue. */
> > +	/**< If rx_enable_queue is true, rte_eth_dev_rx_queue_start
> should be
> > +		invocated to start RX for one queue after rte_eth_dev_start
> is
> > +		invocated, and rte_eth_dev_rx_queue_start instead of
> > +		rte_eth_dev_start is responsible for allocating mbuf from
> > +		mempool and setup the DMA physical address. It is useful in
> > +		such scenario: buffer address is not available at the point of
> > +		rte_eth_dev_start's invocating but available later, e.g. in
> > +		VHOST zero copy case, the buffer address used to setup
> DMA
> > +		address is available only after one VM(guest) startup. */
> > +	uint8_t rx_enable_queue;
> >  };
> 
> I have many comments here.
> 
> The doxygen comment /**< must be used only after the symbol you are
> commenting:
> 	http://doxygen.org/manual/docblocks.html#memberdoc
> 
> The comment is too long.
> The use case would be in the manual, not in doxygen.
> The comment about rte_eth_dev_rx_queue_start would be in the doxygen
> comment of rte_eth_dev_rx_queue_start.
> 
> When this variable is set, it doesn't enable anything. It only disables the
> queue when doing a global start. Its name should be rx_deferred_start.
> All fields of this structure are about one queue, so the "queue" word is not
> needed.
> 
> > -	uint8_t start_tx_per_q; /**< start tx per queue. */
> > +	/**< If tx_enable_queue is true, rte_eth_dev_tx_queue_start must
> be
> > +		invocated to start TX for one queue after rte_eth_dev_start
> is
> > +		invocated. Refer to start_rx_per_q for the use case. */
> > +	uint8_t tx_enable_queue;
> >  };
> 
> You refer to the old name (start_rx_per_q).
> By the way, a one line description (without referral) for both fields should be
> enough. Something like "do not start with rte_eth_dev_start()".
> 
> > @@ -3652,13 +3652,13 @@ ixgbe_dev_rxtx_start(struct rte_eth_dev *dev)
> >
> >  	for (i = 0; i < dev->data->nb_tx_queues; i++) {
> >  		txq = dev->data->tx_queues[i];
> > -		if (!txq->start_tx_per_q)
> > +		if (!txq->tx_enable_queue)
> >  			ixgbe_dev_tx_queue_start(dev, i);
> >  	}
> 
> Here it's clear that this field is about disabling start.
> 
> Please rework this patch and update i40e accordingly.
> Thanks
> --
> Thomas