[RFC,v2,3/5] ethdev: copy ethdev 'burst' API into separate structure

Message ID 20210922140953.19388-4-konstantin.ananyev@intel.com (mailing list archive)
State Superseded, archived
Delegated to: Ferruh Yigit
Headers
Series hide eth dev related structures |

Checks

Context Check Description
ci/checkpatch warning coding style issues

Commit Message

Ananyev, Konstantin Sept. 22, 2021, 2:09 p.m. UTC
  Copy public function pointers (rx_pkt_burst(), etc.) and related
pointers to internal data from rte_eth_dev structure into a separate flat
array. We can keep it public to still use inline functions for 'fast' calls
(like rte_eth_rx_burst(), etc.) to avoid/minimize slowdown.
The intention is to make rte_eth_dev and related structures internal.
That should allow future possible changes to core eth_dev strcutures
to be transaprent to the user and help to avoid ABI/API breakages.

Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
---
 lib/ethdev/ethdev_private.c  | 53 ++++++++++++++++++++++++++++++++++++
 lib/ethdev/ethdev_private.h  |  7 +++++
 lib/ethdev/rte_ethdev.c      | 17 ++++++++++++
 lib/ethdev/rte_ethdev_core.h | 45 ++++++++++++++++++++++++++++++
 4 files changed, 122 insertions(+)
  

Comments

Wang, Haiyue Sept. 23, 2021, 5:58 a.m. UTC | #1
> -----Original Message-----
> From: Ananyev, Konstantin <konstantin.ananyev@intel.com>
> Sent: Wednesday, September 22, 2021 22:10
> To: dev@dpdk.org
> Cc: Li, Xiaoyun <xiaoyun.li@intel.com>; anoobj@marvell.com; jerinj@marvell.com;
> ndabilpuram@marvell.com; adwivedi@marvell.com; shepard.siegel@atomicrules.com;
> ed.czeck@atomicrules.com; john.miller@atomicrules.com; irusskikh@marvell.com;
> ajit.khaparde@broadcom.com; somnath.kotur@broadcom.com; rahul.lakkireddy@chelsio.com;
> hemant.agrawal@nxp.com; sachin.saxena@oss.nxp.com; Wang, Haiyue <haiyue.wang@intel.com>; Daley, John
> <johndale@cisco.com>; hyonkim@cisco.com; Zhang, Qi Z <qi.z.zhang@intel.com>; Wang, Xiao W
> <xiao.w.wang@intel.com>; humin29@huawei.com; yisen.zhuang@huawei.com; oulijun@huawei.com; Xing, Beilei
> <beilei.xing@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>; Yang, Qiming <qiming.yang@intel.com>;
> matan@nvidia.com; viacheslavo@nvidia.com; sthemmin@microsoft.com; longli@microsoft.com;
> heinrich.kuhn@corigine.com; kirankumark@marvell.com; andrew.rybchenko@oktetlabs.ru;
> mczekaj@marvell.com; jiawenwu@trustnetic.com; jianwang@trustnetic.com; maxime.coquelin@redhat.com; Xia,
> Chenbo <chenbo.xia@intel.com>; thomas@monjalon.net; Yigit, Ferruh <ferruh.yigit@intel.com>;
> mdr@ashroe.eu; Jayatheerthan, Jay <jay.jayatheerthan@intel.com>; Ananyev, Konstantin
> <konstantin.ananyev@intel.com>
> Subject: [RFC v2 3/5] ethdev: copy ethdev 'burst' API into separate structure
> 
> Copy public function pointers (rx_pkt_burst(), etc.) and related
> pointers to internal data from rte_eth_dev structure into a separate flat
> array. We can keep it public to still use inline functions for 'fast' calls
> (like rte_eth_rx_burst(), etc.) to avoid/minimize slowdown.
> The intention is to make rte_eth_dev and related structures internal.
> That should allow future possible changes to core eth_dev strcutures
> to be transaprent to the user and help to avoid ABI/API breakages.
> 
> Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> ---
>  lib/ethdev/ethdev_private.c  | 53 ++++++++++++++++++++++++++++++++++++
>  lib/ethdev/ethdev_private.h  |  7 +++++
>  lib/ethdev/rte_ethdev.c      | 17 ++++++++++++
>  lib/ethdev/rte_ethdev_core.h | 45 ++++++++++++++++++++++++++++++
>  4 files changed, 122 insertions(+)
> 
> diff --git a/lib/ethdev/ethdev_private.c b/lib/ethdev/ethdev_private.c
> index 012cf73ca2..a1683da77b 100644
> --- a/lib/ethdev/ethdev_private.c
> +++ b/lib/ethdev/ethdev_private.c
> @@ -174,3 +174,56 @@ rte_eth_devargs_parse_representor_ports(char *str, void *data)
>  		RTE_LOG(ERR, EAL, "wrong representor format: %s\n", str);
>  	return str == NULL ? -1 : 0;
>  }
> +
> +static uint16_t
> +dummy_eth_rx_burst(__rte_unused void *rxq,
> +		__rte_unused struct rte_mbuf **rx_pkts,
> +		__rte_unused uint16_t nb_pkts)
> +{
> +	RTE_ETHDEV_LOG(ERR, "rx_pkt_burst for unconfigured port\n");
> +	rte_errno = ENOTSUP;
> +	return 0;
> +}
> +
> +static uint16_t
> +dummy_eth_tx_burst(__rte_unused void *txq,
> +		__rte_unused struct rte_mbuf **tx_pkts,
> +		__rte_unused uint16_t nb_pkts)
> +{
> +	RTE_ETHDEV_LOG(ERR, "tx_pkt_burst for unconfigured port\n");
> +	rte_errno = ENOTSUP;
> +	return 0;
> +}
> +
> +void
> +eth_dev_burst_api_reset(struct rte_eth_burst_api *rba)
> +{
> +	static void *dummy_data[RTE_MAX_QUEUES_PER_PORT];
> +	static const struct rte_eth_burst_api dummy_api = {
> +		.rx_pkt_burst = dummy_eth_rx_burst,
> +		.tx_pkt_burst = dummy_eth_tx_burst,
> +		.rxq = {.data = dummy_data, .clbk = dummy_data,},
> +		.txq = {.data = dummy_data, .clbk = dummy_data,},
> +	};
> +
> +	*rba = dummy_api;
> +}
> +
> +void
> +eth_dev_burst_api_setup(struct rte_eth_burst_api *rba,
> +		const struct rte_eth_dev *dev)
> +{
> +	rba->rx_pkt_burst = dev->rx_pkt_burst;
> +	rba->tx_pkt_burst = dev->tx_pkt_burst;
> +	rba->tx_pkt_prepare = dev->tx_pkt_prepare;
> +	rba->rx_queue_count = dev->rx_queue_count;
> +	rba->rx_descriptor_status = dev->rx_descriptor_status;
> +	rba->tx_descriptor_status = dev->tx_descriptor_status;
> +
> +	rba->rxq.data = dev->data->rx_queues;
> +	rba->rxq.clbk = (void **)(uintptr_t)dev->post_rx_burst_cbs;
> +
> +	rba->txq.data = dev->data->tx_queues;
> +	rba->txq.clbk = (void **)(uintptr_t)dev->pre_tx_burst_cbs;
> +}
> +
> diff --git a/lib/ethdev/ethdev_private.h b/lib/ethdev/ethdev_private.h
> index 9bb0879538..54921f4860 100644
> --- a/lib/ethdev/ethdev_private.h
> +++ b/lib/ethdev/ethdev_private.h
> @@ -30,6 +30,13 @@ eth_find_device(const struct rte_eth_dev *_start, rte_eth_cmp_t cmp,
>  /* Parse devargs value for representor parameter. */
>  int rte_eth_devargs_parse_representor_ports(char *str, void *data);
> 
> +/* reset eth 'burst' API to dummy values */
> +void eth_dev_burst_api_reset(struct rte_eth_burst_api *rba);
> +
> +/* setup eth 'burst' API to ethdev values */
> +void eth_dev_burst_api_setup(struct rte_eth_burst_api *rba,
> +		const struct rte_eth_dev *dev);
> +
>  #ifdef __cplusplus
>  }
>  #endif
> diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
> index 424bc260fa..5904bb7bae 100644
> --- a/lib/ethdev/rte_ethdev.c
> +++ b/lib/ethdev/rte_ethdev.c
> @@ -44,6 +44,9 @@
>  static const char *MZ_RTE_ETH_DEV_DATA = "rte_eth_dev_data";
>  struct rte_eth_dev rte_eth_devices[RTE_MAX_ETHPORTS];
> 
> +/* public 'fast/burst' API */
> +struct rte_eth_burst_api rte_eth_burst_api[RTE_MAX_ETHPORTS];
> +
>  /* spinlock for eth device callbacks */
>  static rte_spinlock_t eth_dev_cb_lock = RTE_SPINLOCK_INITIALIZER;
> 
> @@ -1788,6 +1791,9 @@ rte_eth_dev_start(uint16_t port_id)
>  		(*dev->dev_ops->link_update)(dev, 0);
>  	}
> 
> +	/* expose selection of PMD rx/tx function */
> +	eth_dev_burst_api_setup(rte_eth_burst_api + port_id, dev);
> +
>  	rte_ethdev_trace_start(port_id);
>  	return 0;
>  }
> @@ -1810,6 +1816,9 @@ rte_eth_dev_stop(uint16_t port_id)
>  		return 0;
>  	}
> 
> +	/* point rx/tx functions to dummy ones */
> +	eth_dev_burst_api_reset(rte_eth_burst_api + port_id);
> +
>  	dev->data->dev_started = 0;
>  	ret = (*dev->dev_ops->dev_stop)(dev);
>  	rte_ethdev_trace_stop(port_id, ret);
> @@ -4568,6 +4577,14 @@ rte_eth_mirror_rule_reset(uint16_t port_id, uint8_t rule_id)
>  	return eth_err(port_id, (*dev->dev_ops->mirror_rule_reset)(dev, rule_id));
>  }
> 
> +RTE_INIT(eth_dev_init_burst_api)
> +{
> +	uint32_t i;
> +
> +	for (i = 0; i != RTE_DIM(rte_eth_burst_api); i++)
> +		eth_dev_burst_api_reset(rte_eth_burst_api + i);
> +}
> +
>  RTE_INIT(eth_dev_init_cb_lists)
>  {
>  	uint16_t i;
> diff --git a/lib/ethdev/rte_ethdev_core.h b/lib/ethdev/rte_ethdev_core.h
> index 00f27c643a..da6de5de43 100644
> --- a/lib/ethdev/rte_ethdev_core.h
> +++ b/lib/ethdev/rte_ethdev_core.h
> @@ -53,6 +53,51 @@ typedef int (*eth_rx_descriptor_status_t)(void *rxq, uint16_t offset);
>  typedef int (*eth_tx_descriptor_status_t)(void *txq, uint16_t offset);
>  /**< @internal Check the status of a Tx descriptor */
> 
> +/**
> + * @internal
> + * Structure used to hold opaque pointernals to internal ethdev RX/TXi
> + * queues data.
> + * The main purpose to expose these pointers at all - allow compiler
> + * to fetch this data for 'fast' ethdev inline functions in advance.
> + */
> +struct rte_ethdev_qdata {
> +	void **data;
> +	/**< points to array of internal queue data pointers */
> +	void **clbk;
> +	/**< points to array of queue callback data pointers */
> +};
> +
> +/**
> + * @internal
> + * 'fast' ethdev funcions and related data are hold in a flat array.
> + * one entry per ethdev.
> + */
> +struct rte_eth_burst_api {

'ops' is better ? Like "struct rte_eth_burst_ops". ;-)

> +
> +	/** first 64B line */
> +	eth_rx_burst_t rx_pkt_burst;
> +	/**< PMD receive function. */
> +	eth_tx_burst_t tx_pkt_burst;
> +	/**< PMD transmit function. */
> +	eth_tx_prep_t tx_pkt_prepare;
> +	/**< PMD transmit prepare function. */
> +	eth_rx_queue_count_t rx_queue_count;
> +	/**< Get the number of used RX descriptors. */
> +	eth_rx_descriptor_status_t rx_descriptor_status;
> +	/**< Check the status of a Rx descriptor. */
> +	eth_tx_descriptor_status_t tx_descriptor_status;
> +	/**< Check the status of a Tx descriptor. */
> +	uintptr_t reserved[2];
> +

How about 32 bit system ? Does it need something like :

__rte_cache_aligned for rxq to make sure 64B line?

> +	/** second 64B line */
> +	struct rte_ethdev_qdata rxq;
> +	struct rte_ethdev_qdata txq;
> +	uintptr_t reserved2[4];
> +
> +} __rte_cache_aligned;
> +
> +extern struct rte_eth_burst_api rte_eth_burst_api[RTE_MAX_ETHPORTS];
> +
> 
>  /**
>   * @internal
> --
> 2.26.3
  
Jerin Jacob Sept. 27, 2021, 6:01 p.m. UTC | #2
On Thu, Sep 23, 2021 at 11:28 AM Wang, Haiyue <haiyue.wang@intel.com> wrote:
>
> > -----Original Message-----
> > From: Ananyev, Konstantin <konstantin.ananyev@intel.com>
> > Sent: Wednesday, September 22, 2021 22:10
> > To: dev@dpdk.org
> > Cc: Li, Xiaoyun <xiaoyun.li@intel.com>; anoobj@marvell.com; jerinj@marvell.com;
> > ndabilpuram@marvell.com; adwivedi@marvell.com; shepard.siegel@atomicrules.com;
> > ed.czeck@atomicrules.com; john.miller@atomicrules.com; irusskikh@marvell.com;
> > ajit.khaparde@broadcom.com; somnath.kotur@broadcom.com; rahul.lakkireddy@chelsio.com;
> > hemant.agrawal@nxp.com; sachin.saxena@oss.nxp.com; Wang, Haiyue <haiyue.wang@intel.com>; Daley, John
> > <johndale@cisco.com>; hyonkim@cisco.com; Zhang, Qi Z <qi.z.zhang@intel.com>; Wang, Xiao W
> > <xiao.w.wang@intel.com>; humin29@huawei.com; yisen.zhuang@huawei.com; oulijun@huawei.com; Xing, Beilei
> > <beilei.xing@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>; Yang, Qiming <qiming.yang@intel.com>;
> > matan@nvidia.com; viacheslavo@nvidia.com; sthemmin@microsoft.com; longli@microsoft.com;
> > heinrich.kuhn@corigine.com; kirankumark@marvell.com; andrew.rybchenko@oktetlabs.ru;
> > mczekaj@marvell.com; jiawenwu@trustnetic.com; jianwang@trustnetic.com; maxime.coquelin@redhat.com; Xia,
> > Chenbo <chenbo.xia@intel.com>; thomas@monjalon.net; Yigit, Ferruh <ferruh.yigit@intel.com>;
> > mdr@ashroe.eu; Jayatheerthan, Jay <jay.jayatheerthan@intel.com>; Ananyev, Konstantin
> > <konstantin.ananyev@intel.com>
> > Subject: [RFC v2 3/5] ethdev: copy ethdev 'burst' API into separate structure
> >
> > Copy public function pointers (rx_pkt_burst(), etc.) and related
> > pointers to internal data from rte_eth_dev structure into a separate flat
> > array. We can keep it public to still use inline functions for 'fast' calls
> > (like rte_eth_rx_burst(), etc.) to avoid/minimize slowdown.
> > The intention is to make rte_eth_dev and related structures internal.
> > That should allow future possible changes to core eth_dev strcutures
> > to be transaprent to the user and help to avoid ABI/API breakages.
> >
> > Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> > ---
> >  lib/ethdev/ethdev_private.c  | 53 ++++++++++++++++++++++++++++++++++++
> >  lib/ethdev/ethdev_private.h  |  7 +++++
> >  lib/ethdev/rte_ethdev.c      | 17 ++++++++++++
> >  lib/ethdev/rte_ethdev_core.h | 45 ++++++++++++++++++++++++++++++
> >  4 files changed, 122 insertions(+)
> >
> > diff --git a/lib/ethdev/ethdev_private.c b/lib/ethdev/ethdev_private.c
> > index 012cf73ca2..a1683da77b 100644
> > --- a/lib/ethdev/ethdev_private.c
> > +++ b/lib/ethdev/ethdev_private.c
> > @@ -174,3 +174,56 @@ rte_eth_devargs_parse_representor_ports(char *str, void *data)
> >               RTE_LOG(ERR, EAL, "wrong representor format: %s\n", str);
> >       return str == NULL ? -1 : 0;
> >  }
> > +
> > +static uint16_t
> > +dummy_eth_rx_burst(__rte_unused void *rxq,
> > +             __rte_unused struct rte_mbuf **rx_pkts,
> > +             __rte_unused uint16_t nb_pkts)
> > +{
> > +     RTE_ETHDEV_LOG(ERR, "rx_pkt_burst for unconfigured port\n");
> > +     rte_errno = ENOTSUP;
> > +     return 0;
> > +}
> > +
> > +static uint16_t
> > +dummy_eth_tx_burst(__rte_unused void *txq,
> > +             __rte_unused struct rte_mbuf **tx_pkts,
> > +             __rte_unused uint16_t nb_pkts)
> > +{
> > +     RTE_ETHDEV_LOG(ERR, "tx_pkt_burst for unconfigured port\n");
> > +     rte_errno = ENOTSUP;
> > +     return 0;
> > +}
> > +
> > +void
> > +eth_dev_burst_api_reset(struct rte_eth_burst_api *rba)
> > +{
> > +     static void *dummy_data[RTE_MAX_QUEUES_PER_PORT];
> > +     static const struct rte_eth_burst_api dummy_api = {
> > +             .rx_pkt_burst = dummy_eth_rx_burst,
> > +             .tx_pkt_burst = dummy_eth_tx_burst,
> > +             .rxq = {.data = dummy_data, .clbk = dummy_data,},
> > +             .txq = {.data = dummy_data, .clbk = dummy_data,},
> > +     };
> > +
> > +     *rba = dummy_api;
> > +}
> > +
> > +void
> > +eth_dev_burst_api_setup(struct rte_eth_burst_api *rba,
> > +             const struct rte_eth_dev *dev)
> > +{
> > +     rba->rx_pkt_burst = dev->rx_pkt_burst;
> > +     rba->tx_pkt_burst = dev->tx_pkt_burst;
> > +     rba->tx_pkt_prepare = dev->tx_pkt_prepare;
> > +     rba->rx_queue_count = dev->rx_queue_count;
> > +     rba->rx_descriptor_status = dev->rx_descriptor_status;
> > +     rba->tx_descriptor_status = dev->tx_descriptor_status;
> > +
> > +     rba->rxq.data = dev->data->rx_queues;
> > +     rba->rxq.clbk = (void **)(uintptr_t)dev->post_rx_burst_cbs;
> > +
> > +     rba->txq.data = dev->data->tx_queues;
> > +     rba->txq.clbk = (void **)(uintptr_t)dev->pre_tx_burst_cbs;
> > +}
> > +
> > diff --git a/lib/ethdev/ethdev_private.h b/lib/ethdev/ethdev_private.h
> > index 9bb0879538..54921f4860 100644
> > --- a/lib/ethdev/ethdev_private.h
> > +++ b/lib/ethdev/ethdev_private.h
> > @@ -30,6 +30,13 @@ eth_find_device(const struct rte_eth_dev *_start, rte_eth_cmp_t cmp,
> >  /* Parse devargs value for representor parameter. */
> >  int rte_eth_devargs_parse_representor_ports(char *str, void *data);
> >
> > +/* reset eth 'burst' API to dummy values */
> > +void eth_dev_burst_api_reset(struct rte_eth_burst_api *rba);
> > +
> > +/* setup eth 'burst' API to ethdev values */
> > +void eth_dev_burst_api_setup(struct rte_eth_burst_api *rba,
> > +             const struct rte_eth_dev *dev);
> > +
> >  #ifdef __cplusplus
> >  }
> >  #endif
> > diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
> > index 424bc260fa..5904bb7bae 100644
> > --- a/lib/ethdev/rte_ethdev.c
> > +++ b/lib/ethdev/rte_ethdev.c
> > @@ -44,6 +44,9 @@
> >  static const char *MZ_RTE_ETH_DEV_DATA = "rte_eth_dev_data";
> >  struct rte_eth_dev rte_eth_devices[RTE_MAX_ETHPORTS];
> >
> > +/* public 'fast/burst' API */
> > +struct rte_eth_burst_api rte_eth_burst_api[RTE_MAX_ETHPORTS];
> > +
> >  /* spinlock for eth device callbacks */
> >  static rte_spinlock_t eth_dev_cb_lock = RTE_SPINLOCK_INITIALIZER;
> >
> > @@ -1788,6 +1791,9 @@ rte_eth_dev_start(uint16_t port_id)
> >               (*dev->dev_ops->link_update)(dev, 0);
> >       }
> >
> > +     /* expose selection of PMD rx/tx function */
> > +     eth_dev_burst_api_setup(rte_eth_burst_api + port_id, dev);
> > +
> >       rte_ethdev_trace_start(port_id);
> >       return 0;
> >  }
> > @@ -1810,6 +1816,9 @@ rte_eth_dev_stop(uint16_t port_id)
> >               return 0;
> >       }
> >
> > +     /* point rx/tx functions to dummy ones */
> > +     eth_dev_burst_api_reset(rte_eth_burst_api + port_id);
> > +
> >       dev->data->dev_started = 0;
> >       ret = (*dev->dev_ops->dev_stop)(dev);
> >       rte_ethdev_trace_stop(port_id, ret);
> > @@ -4568,6 +4577,14 @@ rte_eth_mirror_rule_reset(uint16_t port_id, uint8_t rule_id)
> >       return eth_err(port_id, (*dev->dev_ops->mirror_rule_reset)(dev, rule_id));
> >  }
> >
> > +RTE_INIT(eth_dev_init_burst_api)
> > +{
> > +     uint32_t i;
> > +
> > +     for (i = 0; i != RTE_DIM(rte_eth_burst_api); i++)
> > +             eth_dev_burst_api_reset(rte_eth_burst_api + i);
> > +}
> > +
> >  RTE_INIT(eth_dev_init_cb_lists)
> >  {
> >       uint16_t i;
> > diff --git a/lib/ethdev/rte_ethdev_core.h b/lib/ethdev/rte_ethdev_core.h
> > index 00f27c643a..da6de5de43 100644
> > --- a/lib/ethdev/rte_ethdev_core.h
> > +++ b/lib/ethdev/rte_ethdev_core.h
> > @@ -53,6 +53,51 @@ typedef int (*eth_rx_descriptor_status_t)(void *rxq, uint16_t offset);
> >  typedef int (*eth_tx_descriptor_status_t)(void *txq, uint16_t offset);
> >  /**< @internal Check the status of a Tx descriptor */
> >
> > +/**
> > + * @internal
> > + * Structure used to hold opaque pointernals to internal ethdev RX/TXi
> > + * queues data.
> > + * The main purpose to expose these pointers at all - allow compiler
> > + * to fetch this data for 'fast' ethdev inline functions in advance.
> > + */
> > +struct rte_ethdev_qdata {
> > +     void **data;
> > +     /**< points to array of internal queue data pointers */
> > +     void **clbk;
> > +     /**< points to array of queue callback data pointers */
> > +};
> > +
> > +/**
> > + * @internal
> > + * 'fast' ethdev funcions and related data are hold in a flat array.
> > + * one entry per ethdev.
> > + */
> > +struct rte_eth_burst_api {
>
> 'ops' is better ? Like "struct rte_eth_burst_ops". ;-)

Since all fastpath APIs are not in bust in nature. IMO, rte_eth_fp_ops
or so may be better.

>
> > +
> > +     /** first 64B line */
> > +     eth_rx_burst_t rx_pkt_burst;
> > +     /**< PMD receive function. */
> > +     eth_tx_burst_t tx_pkt_burst;
> > +     /**< PMD transmit function. */
> > +     eth_tx_prep_t tx_pkt_prepare;
> > +     /**< PMD transmit prepare function. */
> > +     eth_rx_queue_count_t rx_queue_count;
> > +     /**< Get the number of used RX descriptors. */
> > +     eth_rx_descriptor_status_t rx_descriptor_status;
> > +     /**< Check the status of a Rx descriptor. */
> > +     eth_tx_descriptor_status_t tx_descriptor_status;
> > +     /**< Check the status of a Tx descriptor. */
> > +     uintptr_t reserved[2];
> > +
>
> How about 32 bit system ? Does it need something like :
>
> __rte_cache_aligned for rxq to make sure 64B line?

__rte_cache_aligned_min for 128B CL systems.

>
> > +     /** second 64B line */
> > +     struct rte_ethdev_qdata rxq;
> > +     struct rte_ethdev_qdata txq;
> > +     uintptr_t reserved2[4];
> > +
> > +} __rte_cache_aligned;
> > +
> > +extern struct rte_eth_burst_api rte_eth_burst_api[RTE_MAX_ETHPORTS];
> > +
> >
> >  /**
> >   * @internal
> > --
> > 2.26.3
>
  
Ananyev, Konstantin Sept. 28, 2021, 9:42 a.m. UTC | #3
> > >
> > > Copy public function pointers (rx_pkt_burst(), etc.) and related
> > > pointers to internal data from rte_eth_dev structure into a separate flat
> > > array. We can keep it public to still use inline functions for 'fast' calls
> > > (like rte_eth_rx_burst(), etc.) to avoid/minimize slowdown.
> > > The intention is to make rte_eth_dev and related structures internal.
> > > That should allow future possible changes to core eth_dev strcutures
> > > to be transaprent to the user and help to avoid ABI/API breakages.
> > >
> > > Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> > > ---
> > >  lib/ethdev/ethdev_private.c  | 53 ++++++++++++++++++++++++++++++++++++
> > >  lib/ethdev/ethdev_private.h  |  7 +++++
> > >  lib/ethdev/rte_ethdev.c      | 17 ++++++++++++
> > >  lib/ethdev/rte_ethdev_core.h | 45 ++++++++++++++++++++++++++++++
> > >  4 files changed, 122 insertions(+)
> > >
> > > diff --git a/lib/ethdev/ethdev_private.c b/lib/ethdev/ethdev_private.c
> > > index 012cf73ca2..a1683da77b 100644
> > > --- a/lib/ethdev/ethdev_private.c
> > > +++ b/lib/ethdev/ethdev_private.c
> > > @@ -174,3 +174,56 @@ rte_eth_devargs_parse_representor_ports(char *str, void *data)
> > >               RTE_LOG(ERR, EAL, "wrong representor format: %s\n", str);
> > >       return str == NULL ? -1 : 0;
> > >  }
> > > +
> > > +static uint16_t
> > > +dummy_eth_rx_burst(__rte_unused void *rxq,
> > > +             __rte_unused struct rte_mbuf **rx_pkts,
> > > +             __rte_unused uint16_t nb_pkts)
> > > +{
> > > +     RTE_ETHDEV_LOG(ERR, "rx_pkt_burst for unconfigured port\n");
> > > +     rte_errno = ENOTSUP;
> > > +     return 0;
> > > +}
> > > +
> > > +static uint16_t
> > > +dummy_eth_tx_burst(__rte_unused void *txq,
> > > +             __rte_unused struct rte_mbuf **tx_pkts,
> > > +             __rte_unused uint16_t nb_pkts)
> > > +{
> > > +     RTE_ETHDEV_LOG(ERR, "tx_pkt_burst for unconfigured port\n");
> > > +     rte_errno = ENOTSUP;
> > > +     return 0;
> > > +}
> > > +
> > > +void
> > > +eth_dev_burst_api_reset(struct rte_eth_burst_api *rba)
> > > +{
> > > +     static void *dummy_data[RTE_MAX_QUEUES_PER_PORT];
> > > +     static const struct rte_eth_burst_api dummy_api = {
> > > +             .rx_pkt_burst = dummy_eth_rx_burst,
> > > +             .tx_pkt_burst = dummy_eth_tx_burst,
> > > +             .rxq = {.data = dummy_data, .clbk = dummy_data,},
> > > +             .txq = {.data = dummy_data, .clbk = dummy_data,},
> > > +     };
> > > +
> > > +     *rba = dummy_api;
> > > +}
> > > +
> > > +void
> > > +eth_dev_burst_api_setup(struct rte_eth_burst_api *rba,
> > > +             const struct rte_eth_dev *dev)
> > > +{
> > > +     rba->rx_pkt_burst = dev->rx_pkt_burst;
> > > +     rba->tx_pkt_burst = dev->tx_pkt_burst;
> > > +     rba->tx_pkt_prepare = dev->tx_pkt_prepare;
> > > +     rba->rx_queue_count = dev->rx_queue_count;
> > > +     rba->rx_descriptor_status = dev->rx_descriptor_status;
> > > +     rba->tx_descriptor_status = dev->tx_descriptor_status;
> > > +
> > > +     rba->rxq.data = dev->data->rx_queues;
> > > +     rba->rxq.clbk = (void **)(uintptr_t)dev->post_rx_burst_cbs;
> > > +
> > > +     rba->txq.data = dev->data->tx_queues;
> > > +     rba->txq.clbk = (void **)(uintptr_t)dev->pre_tx_burst_cbs;
> > > +}
> > > +
> > > diff --git a/lib/ethdev/ethdev_private.h b/lib/ethdev/ethdev_private.h
> > > index 9bb0879538..54921f4860 100644
> > > --- a/lib/ethdev/ethdev_private.h
> > > +++ b/lib/ethdev/ethdev_private.h
> > > @@ -30,6 +30,13 @@ eth_find_device(const struct rte_eth_dev *_start, rte_eth_cmp_t cmp,
> > >  /* Parse devargs value for representor parameter. */
> > >  int rte_eth_devargs_parse_representor_ports(char *str, void *data);
> > >
> > > +/* reset eth 'burst' API to dummy values */
> > > +void eth_dev_burst_api_reset(struct rte_eth_burst_api *rba);
> > > +
> > > +/* setup eth 'burst' API to ethdev values */
> > > +void eth_dev_burst_api_setup(struct rte_eth_burst_api *rba,
> > > +             const struct rte_eth_dev *dev);
> > > +
> > >  #ifdef __cplusplus
> > >  }
> > >  #endif
> > > diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
> > > index 424bc260fa..5904bb7bae 100644
> > > --- a/lib/ethdev/rte_ethdev.c
> > > +++ b/lib/ethdev/rte_ethdev.c
> > > @@ -44,6 +44,9 @@
> > >  static const char *MZ_RTE_ETH_DEV_DATA = "rte_eth_dev_data";
> > >  struct rte_eth_dev rte_eth_devices[RTE_MAX_ETHPORTS];
> > >
> > > +/* public 'fast/burst' API */
> > > +struct rte_eth_burst_api rte_eth_burst_api[RTE_MAX_ETHPORTS];
> > > +
> > >  /* spinlock for eth device callbacks */
> > >  static rte_spinlock_t eth_dev_cb_lock = RTE_SPINLOCK_INITIALIZER;
> > >
> > > @@ -1788,6 +1791,9 @@ rte_eth_dev_start(uint16_t port_id)
> > >               (*dev->dev_ops->link_update)(dev, 0);
> > >       }
> > >
> > > +     /* expose selection of PMD rx/tx function */
> > > +     eth_dev_burst_api_setup(rte_eth_burst_api + port_id, dev);
> > > +
> > >       rte_ethdev_trace_start(port_id);
> > >       return 0;
> > >  }
> > > @@ -1810,6 +1816,9 @@ rte_eth_dev_stop(uint16_t port_id)
> > >               return 0;
> > >       }
> > >
> > > +     /* point rx/tx functions to dummy ones */
> > > +     eth_dev_burst_api_reset(rte_eth_burst_api + port_id);
> > > +
> > >       dev->data->dev_started = 0;
> > >       ret = (*dev->dev_ops->dev_stop)(dev);
> > >       rte_ethdev_trace_stop(port_id, ret);
> > > @@ -4568,6 +4577,14 @@ rte_eth_mirror_rule_reset(uint16_t port_id, uint8_t rule_id)
> > >       return eth_err(port_id, (*dev->dev_ops->mirror_rule_reset)(dev, rule_id));
> > >  }
> > >
> > > +RTE_INIT(eth_dev_init_burst_api)
> > > +{
> > > +     uint32_t i;
> > > +
> > > +     for (i = 0; i != RTE_DIM(rte_eth_burst_api); i++)
> > > +             eth_dev_burst_api_reset(rte_eth_burst_api + i);
> > > +}
> > > +
> > >  RTE_INIT(eth_dev_init_cb_lists)
> > >  {
> > >       uint16_t i;
> > > diff --git a/lib/ethdev/rte_ethdev_core.h b/lib/ethdev/rte_ethdev_core.h
> > > index 00f27c643a..da6de5de43 100644
> > > --- a/lib/ethdev/rte_ethdev_core.h
> > > +++ b/lib/ethdev/rte_ethdev_core.h
> > > @@ -53,6 +53,51 @@ typedef int (*eth_rx_descriptor_status_t)(void *rxq, uint16_t offset);
> > >  typedef int (*eth_tx_descriptor_status_t)(void *txq, uint16_t offset);
> > >  /**< @internal Check the status of a Tx descriptor */
> > >
> > > +/**
> > > + * @internal
> > > + * Structure used to hold opaque pointernals to internal ethdev RX/TXi
> > > + * queues data.
> > > + * The main purpose to expose these pointers at all - allow compiler
> > > + * to fetch this data for 'fast' ethdev inline functions in advance.
> > > + */
> > > +struct rte_ethdev_qdata {
> > > +     void **data;
> > > +     /**< points to array of internal queue data pointers */
> > > +     void **clbk;
> > > +     /**< points to array of queue callback data pointers */
> > > +};
> > > +
> > > +/**
> > > + * @internal
> > > + * 'fast' ethdev funcions and related data are hold in a flat array.
> > > + * one entry per ethdev.
> > > + */
> > > +struct rte_eth_burst_api {
> >
> > 'ops' is better ? Like "struct rte_eth_burst_ops". ;-)
> 
> Since all fastpath APIs are not in bust in nature. IMO, rte_eth_fp_ops
> or so may be better.

I don't have any strong opinion about the name.
Whatever majority will decide is ok by me here.

> 
> >
> > > +
> > > +     /** first 64B line */
> > > +     eth_rx_burst_t rx_pkt_burst;
> > > +     /**< PMD receive function. */
> > > +     eth_tx_burst_t tx_pkt_burst;
> > > +     /**< PMD transmit function. */
> > > +     eth_tx_prep_t tx_pkt_prepare;
> > > +     /**< PMD transmit prepare function. */
> > > +     eth_rx_queue_count_t rx_queue_count;
> > > +     /**< Get the number of used RX descriptors. */
> > > +     eth_rx_descriptor_status_t rx_descriptor_status;
> > > +     /**< Check the status of a Rx descriptor. */
> > > +     eth_tx_descriptor_status_t tx_descriptor_status;
> > > +     /**< Check the status of a Tx descriptor. */
> > > +     uintptr_t reserved[2];
> > > +
> >
> > How about 32 bit system ? Does it need something like :

I don't think we need to anything special for 32-bit version here.
We have 16 pointers here in total right now,
on 32-bit systems it would fit into 64B anyway.

> >
> > __rte_cache_aligned for rxq to make sure 64B line?
> 
> __rte_cache_aligned_min for 128B CL systems.


> 
> >
> > > +     /** second 64B line */
> > > +     struct rte_ethdev_qdata rxq;
> > > +     struct rte_ethdev_qdata txq;
> > > +     uintptr_t reserved2[4];
> > > +
> > > +} __rte_cache_aligned;
> > > +
> > > +extern struct rte_eth_burst_api rte_eth_burst_api[RTE_MAX_ETHPORTS];
> > > +
> > >
> > >  /**
> > >   * @internal
> > > --
> > > 2.26.3
> >
  

Patch

diff --git a/lib/ethdev/ethdev_private.c b/lib/ethdev/ethdev_private.c
index 012cf73ca2..a1683da77b 100644
--- a/lib/ethdev/ethdev_private.c
+++ b/lib/ethdev/ethdev_private.c
@@ -174,3 +174,56 @@  rte_eth_devargs_parse_representor_ports(char *str, void *data)
 		RTE_LOG(ERR, EAL, "wrong representor format: %s\n", str);
 	return str == NULL ? -1 : 0;
 }
+
+static uint16_t
+dummy_eth_rx_burst(__rte_unused void *rxq,
+		__rte_unused struct rte_mbuf **rx_pkts,
+		__rte_unused uint16_t nb_pkts)
+{
+	RTE_ETHDEV_LOG(ERR, "rx_pkt_burst for unconfigured port\n");
+	rte_errno = ENOTSUP;
+	return 0;
+}
+
+static uint16_t
+dummy_eth_tx_burst(__rte_unused void *txq,
+		__rte_unused struct rte_mbuf **tx_pkts,
+		__rte_unused uint16_t nb_pkts)
+{
+	RTE_ETHDEV_LOG(ERR, "tx_pkt_burst for unconfigured port\n");
+	rte_errno = ENOTSUP;
+	return 0;
+}
+
+void
+eth_dev_burst_api_reset(struct rte_eth_burst_api *rba)
+{
+	static void *dummy_data[RTE_MAX_QUEUES_PER_PORT];
+	static const struct rte_eth_burst_api dummy_api = {
+		.rx_pkt_burst = dummy_eth_rx_burst,
+		.tx_pkt_burst = dummy_eth_tx_burst,
+		.rxq = {.data = dummy_data, .clbk = dummy_data,},
+		.txq = {.data = dummy_data, .clbk = dummy_data,},
+	};
+
+	*rba = dummy_api;
+}
+
+void
+eth_dev_burst_api_setup(struct rte_eth_burst_api *rba,
+		const struct rte_eth_dev *dev)
+{
+	rba->rx_pkt_burst = dev->rx_pkt_burst;
+	rba->tx_pkt_burst = dev->tx_pkt_burst;
+	rba->tx_pkt_prepare = dev->tx_pkt_prepare;
+	rba->rx_queue_count = dev->rx_queue_count;
+	rba->rx_descriptor_status = dev->rx_descriptor_status;
+	rba->tx_descriptor_status = dev->tx_descriptor_status;
+
+	rba->rxq.data = dev->data->rx_queues;
+	rba->rxq.clbk = (void **)(uintptr_t)dev->post_rx_burst_cbs;
+
+	rba->txq.data = dev->data->tx_queues;
+	rba->txq.clbk = (void **)(uintptr_t)dev->pre_tx_burst_cbs;
+}
+
diff --git a/lib/ethdev/ethdev_private.h b/lib/ethdev/ethdev_private.h
index 9bb0879538..54921f4860 100644
--- a/lib/ethdev/ethdev_private.h
+++ b/lib/ethdev/ethdev_private.h
@@ -30,6 +30,13 @@  eth_find_device(const struct rte_eth_dev *_start, rte_eth_cmp_t cmp,
 /* Parse devargs value for representor parameter. */
 int rte_eth_devargs_parse_representor_ports(char *str, void *data);
 
+/* reset eth 'burst' API to dummy values */
+void eth_dev_burst_api_reset(struct rte_eth_burst_api *rba);
+
+/* setup eth 'burst' API to ethdev values */
+void eth_dev_burst_api_setup(struct rte_eth_burst_api *rba,
+		const struct rte_eth_dev *dev);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index 424bc260fa..5904bb7bae 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -44,6 +44,9 @@ 
 static const char *MZ_RTE_ETH_DEV_DATA = "rte_eth_dev_data";
 struct rte_eth_dev rte_eth_devices[RTE_MAX_ETHPORTS];
 
+/* public 'fast/burst' API */
+struct rte_eth_burst_api rte_eth_burst_api[RTE_MAX_ETHPORTS];
+
 /* spinlock for eth device callbacks */
 static rte_spinlock_t eth_dev_cb_lock = RTE_SPINLOCK_INITIALIZER;
 
@@ -1788,6 +1791,9 @@  rte_eth_dev_start(uint16_t port_id)
 		(*dev->dev_ops->link_update)(dev, 0);
 	}
 
+	/* expose selection of PMD rx/tx function */
+	eth_dev_burst_api_setup(rte_eth_burst_api + port_id, dev);
+
 	rte_ethdev_trace_start(port_id);
 	return 0;
 }
@@ -1810,6 +1816,9 @@  rte_eth_dev_stop(uint16_t port_id)
 		return 0;
 	}
 
+	/* point rx/tx functions to dummy ones */
+	eth_dev_burst_api_reset(rte_eth_burst_api + port_id);
+
 	dev->data->dev_started = 0;
 	ret = (*dev->dev_ops->dev_stop)(dev);
 	rte_ethdev_trace_stop(port_id, ret);
@@ -4568,6 +4577,14 @@  rte_eth_mirror_rule_reset(uint16_t port_id, uint8_t rule_id)
 	return eth_err(port_id, (*dev->dev_ops->mirror_rule_reset)(dev, rule_id));
 }
 
+RTE_INIT(eth_dev_init_burst_api)
+{
+	uint32_t i;
+
+	for (i = 0; i != RTE_DIM(rte_eth_burst_api); i++)
+		eth_dev_burst_api_reset(rte_eth_burst_api + i);
+}
+
 RTE_INIT(eth_dev_init_cb_lists)
 {
 	uint16_t i;
diff --git a/lib/ethdev/rte_ethdev_core.h b/lib/ethdev/rte_ethdev_core.h
index 00f27c643a..da6de5de43 100644
--- a/lib/ethdev/rte_ethdev_core.h
+++ b/lib/ethdev/rte_ethdev_core.h
@@ -53,6 +53,51 @@  typedef int (*eth_rx_descriptor_status_t)(void *rxq, uint16_t offset);
 typedef int (*eth_tx_descriptor_status_t)(void *txq, uint16_t offset);
 /**< @internal Check the status of a Tx descriptor */
 
+/**
+ * @internal
+ * Structure used to hold opaque pointernals to internal ethdev RX/TXi
+ * queues data.
+ * The main purpose to expose these pointers at all - allow compiler
+ * to fetch this data for 'fast' ethdev inline functions in advance.
+ */
+struct rte_ethdev_qdata {
+	void **data;
+	/**< points to array of internal queue data pointers */
+	void **clbk;
+	/**< points to array of queue callback data pointers */
+};
+
+/**
+ * @internal
+ * 'fast' ethdev funcions and related data are hold in a flat array.
+ * one entry per ethdev.
+ */
+struct rte_eth_burst_api {
+
+	/** first 64B line */
+	eth_rx_burst_t rx_pkt_burst;
+	/**< PMD receive function. */
+	eth_tx_burst_t tx_pkt_burst;
+	/**< PMD transmit function. */
+	eth_tx_prep_t tx_pkt_prepare;
+	/**< PMD transmit prepare function. */
+	eth_rx_queue_count_t rx_queue_count;
+	/**< Get the number of used RX descriptors. */
+	eth_rx_descriptor_status_t rx_descriptor_status;
+	/**< Check the status of a Rx descriptor. */
+	eth_tx_descriptor_status_t tx_descriptor_status;
+	/**< Check the status of a Tx descriptor. */
+	uintptr_t reserved[2];
+
+	/** second 64B line */
+	struct rte_ethdev_qdata rxq;
+	struct rte_ethdev_qdata txq;
+	uintptr_t reserved2[4];
+
+} __rte_cache_aligned;
+
+extern struct rte_eth_burst_api rte_eth_burst_api[RTE_MAX_ETHPORTS];
+
 
 /**
  * @internal