Re: [dpdk-dev] [PATCH v6 12/19] net/ngbe: add Rx queue setup and release

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

On 7/5/21 11:36 AM, Jiawen Wu wrote:
> On July 3, 2021 12:36 AM, Andrew Rybchenko wrote:
>> On 6/17/21 1:59 PM, Jiawen Wu wrote:
>>> Setup device Rx queue and release Rx queue.
>>>
>>> Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
>>> ---
>>>  drivers/net/ngbe/meson.build   |   1 +
>>>  drivers/net/ngbe/ngbe_ethdev.c |  37 +++-
>>> drivers/net/ngbe/ngbe_ethdev.h |  16 ++
>>>  drivers/net/ngbe/ngbe_rxtx.c   | 308 +++++++++++++++++++++++++++++++++
>>>  drivers/net/ngbe/ngbe_rxtx.h   |  96 ++++++++++
>>>  5 files changed, 457 insertions(+), 1 deletion(-)  create mode 100644
>>> drivers/net/ngbe/ngbe_rxtx.c  create mode 100644
>>> drivers/net/ngbe/ngbe_rxtx.h
>>>
>>> diff --git a/drivers/net/ngbe/meson.build
>>> b/drivers/net/ngbe/meson.build index 81173fa7f0..9e75b82f1c 100644
>>> --- a/drivers/net/ngbe/meson.build
>>> +++ b/drivers/net/ngbe/meson.build
>>> @@ -12,6 +12,7 @@ objs = [base_objs]
>>>
>>>  sources = files(
>>>  	'ngbe_ethdev.c',
>>> +	'ngbe_rxtx.c',
>>>  )
>>>
>>>  includes += include_directories('base') diff --git
>>> a/drivers/net/ngbe/ngbe_ethdev.c b/drivers/net/ngbe/ngbe_ethdev.c
>>> index c952023e8b..e73606c5f3 100644
>>> --- a/drivers/net/ngbe/ngbe_ethdev.c
>>> +++ b/drivers/net/ngbe/ngbe_ethdev.c
>>> @@ -12,6 +12,7 @@
>>>  #include "ngbe_logs.h"
>>>  #include "base/ngbe.h"
>>>  #include "ngbe_ethdev.h"
>>> +#include "ngbe_rxtx.h"
>>>
>>>  static int ngbe_dev_close(struct rte_eth_dev *dev);
>>>
>>> @@ -37,6 +38,12 @@ static const struct rte_pci_id pci_id_ngbe_map[] = {
>>>  	{ .vendor_id = 0, /* sentinel */ },
>>>  };
>>>
>>> +static const struct rte_eth_desc_lim rx_desc_lim = {
>>> +	.nb_max = NGBE_RING_DESC_MAX,
>>> +	.nb_min = NGBE_RING_DESC_MIN,
>>> +	.nb_align = NGBE_RXD_ALIGN,
>>> +};
>>> +
>>>  static const struct eth_dev_ops ngbe_eth_dev_ops;
>>>
>>>  static inline void
>>> @@ -241,12 +248,19 @@ static int
>>>  ngbe_dev_configure(struct rte_eth_dev *dev)  {
>>>  	struct ngbe_interrupt *intr = ngbe_dev_intr(dev);
>>> +	struct ngbe_adapter *adapter = ngbe_dev_adapter(dev);
>>>
>>>  	PMD_INIT_FUNC_TRACE();
>>>
>>>  	/* set flag to update link status after init */
>>>  	intr->flags |= NGBE_FLAG_NEED_LINK_UPDATE;
>>>
>>> +	/*
>>> +	 * Initialize to TRUE. If any of Rx queues doesn't meet the bulk
>>> +	 * allocation Rx preconditions we will reset it.
>>> +	 */
>>> +	adapter->rx_bulk_alloc_allowed = true;
>>> +
>>>  	return 0;
>>>  }
>>>
>>> @@ -266,11 +280,30 @@ ngbe_dev_close(struct rte_eth_dev *dev)  static
>>> int  ngbe_dev_info_get(struct rte_eth_dev *dev, struct
>>> rte_eth_dev_info *dev_info)  {
>>> -	RTE_SET_USED(dev);
>>> +	struct ngbe_hw *hw = ngbe_dev_hw(dev);
>>> +
>>> +	dev_info->max_rx_queues = (uint16_t)hw->mac.max_rx_queues;
>>> +
>>> +	dev_info->default_rxconf = (struct rte_eth_rxconf) {
>>> +		.rx_thresh = {
>>> +			.pthresh = NGBE_DEFAULT_RX_PTHRESH,
>>> +			.hthresh = NGBE_DEFAULT_RX_HTHRESH,
>>> +			.wthresh = NGBE_DEFAULT_RX_WTHRESH,
>>> +		},
>>> +		.rx_free_thresh = NGBE_DEFAULT_RX_FREE_THRESH,
>>> +		.rx_drop_en = 0,
>>> +		.offloads = 0,
>>> +	};
>>> +
>>> +	dev_info->rx_desc_lim = rx_desc_lim;
>>>
>>>  	dev_info->speed_capa = ETH_LINK_SPEED_1G | ETH_LINK_SPEED_100M |
>>>  				ETH_LINK_SPEED_10M;
>>>
>>> +	/* Driver-preferred Rx/Tx parameters */
>>> +	dev_info->default_rxportconf.nb_queues = 1;
>>> +	dev_info->default_rxportconf.ring_size = 256;
>>> +
>>>  	return 0;
>>>  }
>>>
>>> @@ -570,6 +603,8 @@ static const struct eth_dev_ops ngbe_eth_dev_ops =
>> {
>>>  	.dev_configure              = ngbe_dev_configure,
>>>  	.dev_infos_get              = ngbe_dev_info_get,
>>>  	.link_update                = ngbe_dev_link_update,
>>> +	.rx_queue_setup             = ngbe_dev_rx_queue_setup,
>>> +	.rx_queue_release           = ngbe_dev_rx_queue_release,
>>>  };
>>>
>>>  RTE_PMD_REGISTER_PCI(net_ngbe, rte_ngbe_pmd); diff --git
>>> a/drivers/net/ngbe/ngbe_ethdev.h b/drivers/net/ngbe/ngbe_ethdev.h
>>> index b67508a3de..6580d288c8 100644
>>> --- a/drivers/net/ngbe/ngbe_ethdev.h
>>> +++ b/drivers/net/ngbe/ngbe_ethdev.h
>>> @@ -30,6 +30,7 @@ struct ngbe_interrupt {  struct ngbe_adapter {
>>>  	struct ngbe_hw             hw;
>>>  	struct ngbe_interrupt      intr;
>>> +	bool rx_bulk_alloc_allowed;
>>
>> Shouldn't it be aligned as well as above fields?
>>
>>>  };
>>>
>>>  static inline struct ngbe_adapter *
>>> @@ -58,6 +59,13 @@ ngbe_dev_intr(struct rte_eth_dev *dev)
>>>  	return intr;
>>>  }
>>>
>>> +void ngbe_dev_rx_queue_release(void *rxq);
>>> +
>>> +int  ngbe_dev_rx_queue_setup(struct rte_eth_dev *dev, uint16_t rx_queue_id,
>>> +		uint16_t nb_rx_desc, unsigned int socket_id,
>>> +		const struct rte_eth_rxconf *rx_conf,
>>> +		struct rte_mempool *mb_pool);
>>> +
>>>  int
>>>  ngbe_dev_link_update_share(struct rte_eth_dev *dev,
>>>  		int wait_to_complete);
>>> @@ -66,4 +74,12 @@ ngbe_dev_link_update_share(struct rte_eth_dev *dev,
>>>  #define NGBE_LINK_UP_CHECK_TIMEOUT   1000 /* ms */
>>>  #define NGBE_VMDQ_NUM_UC_MAC         4096 /* Maximum nb. of UC MAC addr. */
>>>
>>> +/*
>>> + *  Default values for Rx/Tx configuration  */ #define
>>> +NGBE_DEFAULT_RX_FREE_THRESH  32
>>> +#define NGBE_DEFAULT_RX_PTHRESH      8
>>> +#define NGBE_DEFAULT_RX_HTHRESH      8
>>> +#define NGBE_DEFAULT_RX_WTHRESH      0
>>> +
>>>  #endif /* _NGBE_ETHDEV_H_ */
>>> diff --git a/drivers/net/ngbe/ngbe_rxtx.c
>>> b/drivers/net/ngbe/ngbe_rxtx.c new file mode 100644 index
>>> 0000000000..df0b64dc01
>>> --- /dev/null
>>> +++ b/drivers/net/ngbe/ngbe_rxtx.c
>>> @@ -0,0 +1,308 @@
>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>> + * Copyright(c) 2018-2020 Beijing WangXun Technology Co., Ltd.
>>> + * Copyright(c) 2010-2017 Intel Corporation  */
>>> +
>>> +#include <sys/queue.h>
>>> +
>>> +#include <stdint.h>
>>> +#include <rte_ethdev.h>
>>> +#include <ethdev_driver.h>
>>> +#include <rte_malloc.h>
>>> +
>>> +#include "ngbe_logs.h"
>>> +#include "base/ngbe.h"
>>> +#include "ngbe_ethdev.h"
>>> +#include "ngbe_rxtx.h"
>>> +
>>> +/**
>>> + * ngbe_free_sc_cluster - free the not-yet-completed scattered
>>> +cluster
>>> + *
>>> + * The "next" pointer of the last segment of (not-yet-completed) RSC
>>> +clusters
>>> + * in the sw_sc_ring is not set to NULL but rather points to the next
>>> + * mbuf of this RSC aggregation (that has not been completed yet and
>>> +still
>>> + * resides on the HW ring). So, instead of calling for
>>> +rte_pktmbuf_free() we
>>> + * will just free first "nb_segs" segments of the cluster explicitly
>>> +by calling
>>> + * an rte_pktmbuf_free_seg().
>>> + *
>>> + * @m scattered cluster head
>>> + */
>>> +static void __rte_cold
>>> +ngbe_free_sc_cluster(struct rte_mbuf *m) {
>>> +	uint16_t i, nb_segs = m->nb_segs;
>>> +	struct rte_mbuf *next_seg;
>>> +
>>> +	for (i = 0; i < nb_segs; i++) {
>>> +		next_seg = m->next;
>>> +		rte_pktmbuf_free_seg(m);
>>> +		m = next_seg;
>>> +	}
>>> +}
>>> +
>>> +static void __rte_cold
>>> +ngbe_rx_queue_release_mbufs(struct ngbe_rx_queue *rxq) {
>>> +	unsigned int i;
>>> +
>>> +	if (rxq->sw_ring != NULL) {
>>> +		for (i = 0; i < rxq->nb_rx_desc; i++) {
>>> +			if (rxq->sw_ring[i].mbuf != NULL) {
>>> +				rte_pktmbuf_free_seg(rxq->sw_ring[i].mbuf);
>>> +				rxq->sw_ring[i].mbuf = NULL;
>>> +			}
>>> +		}
>>> +		if (rxq->rx_nb_avail) {
>>
>> Compare vs 0 explicitly. However, it looks like that the check is not required at
>> all. Body may be done unconditionally.
>>
>>> +			for (i = 0; i < rxq->rx_nb_avail; ++i) {
>>> +				struct rte_mbuf *mb;
>>> +
>>> +				mb = rxq->rx_stage[rxq->rx_next_avail + i];
>>> +				rte_pktmbuf_free_seg(mb);
>>> +			}
>>> +			rxq->rx_nb_avail = 0;
>>> +		}
>>> +	}
>>> +
>>> +	if (rxq->sw_sc_ring != NULL)
>>> +		for (i = 0; i < rxq->nb_rx_desc; i++)
>>> +			if (rxq->sw_sc_ring[i].fbuf) {
>>
>> Compare vs NULL
>>
>>> +				ngbe_free_sc_cluster(rxq->sw_sc_ring[i].fbuf);
>>> +				rxq->sw_sc_ring[i].fbuf = NULL;
>>> +			}
>>> +}
>>> +
>>> +static void __rte_cold
>>> +ngbe_rx_queue_release(struct ngbe_rx_queue *rxq) {
>>> +	if (rxq != NULL) {
>>> +		ngbe_rx_queue_release_mbufs(rxq);
>>> +		rte_free(rxq->sw_ring);
>>> +		rte_free(rxq->sw_sc_ring);
>>> +		rte_free(rxq);
>>> +	}
>>> +}
>>> +
>>> +void __rte_cold
>>> +ngbe_dev_rx_queue_release(void *rxq)
>>> +{
>>> +	ngbe_rx_queue_release(rxq);
>>> +}
>>> +
>>> +/*
>>> + * Check if Rx Burst Bulk Alloc function can be used.
>>> + * Return
>>> + *        0: the preconditions are satisfied and the bulk allocation function
>>> + *           can be used.
>>> + *  -EINVAL: the preconditions are NOT satisfied and the default Rx burst
>>> + *           function must be used.
>>> + */
>>> +static inline int __rte_cold
>>> +check_rx_burst_bulk_alloc_preconditions(struct ngbe_rx_queue *rxq) {
>>> +	int ret = 0;
>>> +
>>> +	/*
>>> +	 * Make sure the following pre-conditions are satisfied:
>>> +	 *   rxq->rx_free_thresh >= RTE_PMD_NGBE_RX_MAX_BURST
>>> +	 *   rxq->rx_free_thresh < rxq->nb_rx_desc
>>> +	 *   (rxq->nb_rx_desc % rxq->rx_free_thresh) == 0
>>> +	 * Scattered packets are not supported.  This should be checked
>>> +	 * outside of this function.
>>> +	 */
>>> +	if (!(rxq->rx_free_thresh >= RTE_PMD_NGBE_RX_MAX_BURST)) {
>>
>> Isn't is simpler to read and understand:
>> rxq->rx_free_thresh < RTE_PMD_NGBE_RX_MAX_BURST
>>
>>> +		PMD_INIT_LOG(DEBUG, "Rx Burst Bulk Alloc Preconditions: "
>>> +			     "rxq->rx_free_thresh=%d, "
>>> +			     "RTE_PMD_NGBE_RX_MAX_BURST=%d",
>>
>> Do not split format string.
>>
>>> +			     rxq->rx_free_thresh, RTE_PMD_NGBE_RX_MAX_BURST);
>>> +		ret = -EINVAL;
>>> +	} else if (!(rxq->rx_free_thresh < rxq->nb_rx_desc)) {
>>
>> rxq->rx_free_thresh >= rxq->nb_rx_desc
>> is simpler to read
>>
>>> +		PMD_INIT_LOG(DEBUG, "Rx Burst Bulk Alloc Preconditions: "
>>> +			     "rxq->rx_free_thresh=%d, "
>>> +			     "rxq->nb_rx_desc=%d",
>>
>> Do not split format string.
>>
>>> +			     rxq->rx_free_thresh, rxq->nb_rx_desc);
>>> +		ret = -EINVAL;
>>> +	} else if (!((rxq->nb_rx_desc % rxq->rx_free_thresh) == 0)) {
>>
>> (rxq->nb_rx_desc % rxq->rx_free_thresh) != 0 is easier to read
>>
>>> +		PMD_INIT_LOG(DEBUG, "Rx Burst Bulk Alloc Preconditions: "
>>> +			     "rxq->nb_rx_desc=%d, "
>>> +			     "rxq->rx_free_thresh=%d",
>>> +			     rxq->nb_rx_desc, rxq->rx_free_thresh);
>>
>> Do not split format string
>>
>>> +		ret = -EINVAL;
>>> +	}
>>> +
>>> +	return ret;
>>> +}
>>> +
>>> +/* Reset dynamic ngbe_rx_queue fields back to defaults */ static void
>>> +__rte_cold ngbe_reset_rx_queue(struct ngbe_adapter *adapter, struct
>>> +ngbe_rx_queue *rxq) {
>>> +	static const struct ngbe_rx_desc zeroed_desc = {
>>> +						{{0}, {0} }, {{0}, {0} } };
>>> +	unsigned int i;
>>> +	uint16_t len = rxq->nb_rx_desc;
>>> +
>>> +	/*
>>> +	 * By default, the Rx queue setup function allocates enough memory for
>>> +	 * NGBE_RING_DESC_MAX.  The Rx Burst bulk allocation function requires
>>> +	 * extra memory at the end of the descriptor ring to be zero'd out.
>>> +	 */
>>> +	if (adapter->rx_bulk_alloc_allowed)
>>> +		/* zero out extra memory */
>>> +		len += RTE_PMD_NGBE_RX_MAX_BURST;
>>> +
>>> +	/*
>>> +	 * Zero out HW ring memory. Zero out extra memory at the end of
>>> +	 * the H/W ring so look-ahead logic in Rx Burst bulk alloc function
>>> +	 * reads extra memory as zeros.
>>> +	 */
>>> +	for (i = 0; i < len; i++)
>>> +		rxq->rx_ring[i] = zeroed_desc;
>>> +
>>> +	/*
>>> +	 * initialize extra software ring entries. Space for these extra
>>> +	 * entries is always allocated
>>> +	 */
>>> +	memset(&rxq->fake_mbuf, 0x0, sizeof(rxq->fake_mbuf));
>>> +	for (i = rxq->nb_rx_desc; i < len; ++i)
>>> +		rxq->sw_ring[i].mbuf = &rxq->fake_mbuf;
>>> +
>>> +	rxq->rx_nb_avail = 0;
>>> +	rxq->rx_next_avail = 0;
>>> +	rxq->rx_free_trigger = (uint16_t)(rxq->rx_free_thresh - 1);
>>> +	rxq->rx_tail = 0;
>>> +	rxq->nb_rx_hold = 0;
>>> +	rxq->pkt_first_seg = NULL;
>>> +	rxq->pkt_last_seg = NULL;
>>> +}
>>> +
>>> +int __rte_cold
>>> +ngbe_dev_rx_queue_setup(struct rte_eth_dev *dev,
>>> +			 uint16_t queue_idx,
>>> +			 uint16_t nb_desc,
>>> +			 unsigned int socket_id,
>>> +			 const struct rte_eth_rxconf *rx_conf,
>>> +			 struct rte_mempool *mp)
>>> +{
>>> +	const struct rte_memzone *rz;
>>> +	struct ngbe_rx_queue *rxq;
>>> +	struct ngbe_hw     *hw;
>>> +	uint16_t len;
>>> +	struct ngbe_adapter *adapter = ngbe_dev_adapter(dev);
>>> +
>>> +	PMD_INIT_FUNC_TRACE();
>>> +	hw = ngbe_dev_hw(dev);
>>> +
>>> +	/*
>>> +	 * Validate number of receive descriptors.
>>> +	 * It must not exceed hardware maximum, and must be multiple
>>> +	 * of NGBE_ALIGN.
>>> +	 */
>>> +	if (nb_desc % NGBE_RXD_ALIGN != 0 ||
>>> +			nb_desc > NGBE_RING_DESC_MAX ||
>>> +			nb_desc < NGBE_RING_DESC_MIN) {
>>> +		return -EINVAL;
>>> +	}
>>
>> rte_eth_rx_queue_setup cares about it
>>
> 
> I don't quite understand.

ethdev does the check based dev_info provided by the driver:

if (nb_rx_desc > dev_info.rx_desc_lim.nb_max ||
    nb_rx_desc < dev_info.rx_desc_lim.nb_min ||
    nb_rx_desc % dev_info.rx_desc_lim.nb_align != 0) {
        RTE_ETHDEV_LOG(ERR,
            "Invalid value for nb_rx_desc(=%hu), should be: <= %hu, >=
%hu, and a product of %hu\n",
            nb_rx_desc, dev_info.rx_desc_lim.nb_max,
            dev_info.rx_desc_lim.nb_min,
            dev_info.rx_desc_lim.nb_align);
       return -EINVAL;
}