From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id D30CDA0C41; Sat, 9 Oct 2021 14:05:28 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 6374C40042; Sat, 9 Oct 2021 14:05:28 +0200 (CEST) Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by mails.dpdk.org (Postfix) with ESMTP id 8D7F740040 for ; Sat, 9 Oct 2021 14:05:25 +0200 (CEST) Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.57]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4HRNyX56ZvzQj66; Sat, 9 Oct 2021 20:04:20 +0800 (CST) Received: from dggpeml500024.china.huawei.com (7.185.36.10) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Sat, 9 Oct 2021 20:05:20 +0800 Received: from [127.0.0.1] (10.67.100.224) by dggpeml500024.china.huawei.com (7.185.36.10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Sat, 9 Oct 2021 20:05:20 +0800 To: Konstantin Ananyev , CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , References: <20211004135603.20593-1-konstantin.ananyev@intel.com> <20211007112750.25526-1-konstantin.ananyev@intel.com> <20211007112750.25526-5-konstantin.ananyev@intel.com> From: fengchengwen Message-ID: <4c57bb9d-21d6-0722-92b8-987283bb8fe6@huawei.com> Date: Sat, 9 Oct 2021 20:05:19 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <20211007112750.25526-5-konstantin.ananyev@intel.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.100.224] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpeml500024.china.huawei.com (7.185.36.10) X-CFilter-Loop: Reflected Subject: Re: [dpdk-dev] [PATCH v5 4/7] ethdev: copy fast-path API into separate structure X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 2021/10/7 19:27, Konstantin Ananyev wrote: > Copy public function pointers (rx_pkt_burst(), etc.) and related > pointers to internal data from rte_eth_dev structure into a > separate flat array. That array will remain in a public header. > The intention here is to make rte_eth_dev and related structures internal. > That should allow future possible changes to core eth_dev structures > to be transparent to the user and help to avoid ABI/API breakages. > The plan is to keep minimal part of data from rte_eth_dev public, > so we still can use inline functions for fast-path calls > (like rte_eth_rx_burst(), etc.) to avoid/minimize slowdown. > The whole idea beyond this new schema: > 1. PMDs keep to setup fast-path function pointers and related data > inside rte_eth_dev struct in the same way they did it before. > 2. Inside rte_eth_dev_start() and inside rte_eth_dev_probing_finish() > (for secondary process) we call eth_dev_fp_ops_setup, which > copies these function and data pointers into rte_eth_fp_ops[port_id]. > 3. Inside rte_eth_dev_stop() and inside rte_eth_dev_release_port() > we call eth_dev_fp_ops_reset(), which resets rte_eth_fp_ops[port_id] > into some dummy values. > 4. fast-path ethdev API (rte_eth_rx_burst(), etc.) will use that new > flat array to call PMD specific functions. > That approach should allow us to make rte_eth_devices[] private > without introducing regression and help to avoid changes in drivers code. > > Signed-off-by: Konstantin Ananyev > --- > lib/ethdev/ethdev_private.c | 52 ++++++++++++++++++++++++++++++++++ > lib/ethdev/ethdev_private.h | 7 +++++ > lib/ethdev/rte_ethdev.c | 27 ++++++++++++++++++ > lib/ethdev/rte_ethdev_core.h | 55 ++++++++++++++++++++++++++++++++++++ > 4 files changed, 141 insertions(+) > > diff --git a/lib/ethdev/ethdev_private.c b/lib/ethdev/ethdev_private.c > index 012cf73ca2..3eeda6e9f9 100644 > --- a/lib/ethdev/ethdev_private.c > +++ b/lib/ethdev/ethdev_private.c > @@ -174,3 +174,55 @@ 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_fp_ops_reset(struct rte_eth_fp_ops *fpo) The port_id parameter is preferable, this will hide rte_eth_fp_ops as much as possible. > +{ > + static void *dummy_data[RTE_MAX_QUEUES_PER_PORT]; > + static const struct rte_eth_fp_ops dummy_ops = { > + .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,}, > + }; > + > + *fpo = dummy_ops; > +} > + > +void > +eth_dev_fp_ops_setup(struct rte_eth_fp_ops *fpo, > + const struct rte_eth_dev *dev) Because fp_ops and eth_dev is a one-to-one correspondence. It's better only use port_id parameter. > +{ > + fpo->rx_pkt_burst = dev->rx_pkt_burst; > + fpo->tx_pkt_burst = dev->tx_pkt_burst; > + fpo->tx_pkt_prepare = dev->tx_pkt_prepare; > + fpo->rx_queue_count = dev->rx_queue_count; > + fpo->rx_descriptor_status = dev->rx_descriptor_status; > + fpo->tx_descriptor_status = dev->tx_descriptor_status; > + > + fpo->rxq.data = dev->data->rx_queues; > + fpo->rxq.clbk = (void **)(uintptr_t)dev->post_rx_burst_cbs; > + > + fpo->txq.data = dev->data->tx_queues; > + fpo->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 3724429577..5721be7bdc 100644 > --- a/lib/ethdev/ethdev_private.h > +++ b/lib/ethdev/ethdev_private.h > @@ -26,4 +26,11 @@ 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 fast-path API to dummy values */ > +void eth_dev_fp_ops_reset(struct rte_eth_fp_ops *fpo); > + > +/* setup eth fast-path API to ethdev values */ > +void eth_dev_fp_ops_setup(struct rte_eth_fp_ops *fpo, > + const struct rte_eth_dev *dev); Some drivers control the transmit/receive function during operation. E.g. for hns3 driver, when detect reset, primary process will set rx/tx burst to dummy, after process reset, primary process will set the correct rx/tx burst. During this process, the send and receive threads are still working, but the bursts they call are changed. So: 1. it is recommended that trace be deleted from the dummy function. 2. public the eth_dev_fp_ops_reset/setup interface for driver usage. > + > #endif /* _ETH_PRIVATE_H_ */ > diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c > index c8abda6dd7..9f7a0cbb8c 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-path API */ > +struct rte_eth_fp_ops rte_eth_fp_ops[RTE_MAX_ETHPORTS]; > + > /* spinlock for eth device callbacks */ > static rte_spinlock_t eth_dev_cb_lock = RTE_SPINLOCK_INITIALIZER; > > @@ -578,6 +581,8 @@ rte_eth_dev_release_port(struct rte_eth_dev *eth_dev) > rte_eth_dev_callback_process(eth_dev, > RTE_ETH_EVENT_DESTROY, NULL); > > + eth_dev_fp_ops_reset(rte_eth_fp_ops + eth_dev->data->port_id); > + > rte_spinlock_lock(ð_dev_shared_data->ownership_lock); > > eth_dev->state = RTE_ETH_DEV_UNUSED; > @@ -1787,6 +1792,9 @@ rte_eth_dev_start(uint16_t port_id) > (*dev->dev_ops->link_update)(dev, 0); > } > > + /* expose selection of PMD fast-path functions */ > + eth_dev_fp_ops_setup(rte_eth_fp_ops + port_id, dev); > + > rte_ethdev_trace_start(port_id); > return 0; > } > @@ -1809,6 +1817,9 @@ rte_eth_dev_stop(uint16_t port_id) > return 0; > } > > + /* point fast-path functions to dummy ones */ > + eth_dev_fp_ops_reset(rte_eth_fp_ops + port_id); > + > dev->data->dev_started = 0; > ret = (*dev->dev_ops->dev_stop)(dev); > rte_ethdev_trace_stop(port_id, ret); > @@ -4567,6 +4578,14 @@ 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_fp_ops) > +{ > + uint32_t i; > + > + for (i = 0; i != RTE_DIM(rte_eth_fp_ops); i++) > + eth_dev_fp_ops_reset(rte_eth_fp_ops + i); > +} > + > RTE_INIT(eth_dev_init_cb_lists) > { > uint16_t i; > @@ -4735,6 +4754,14 @@ rte_eth_dev_probing_finish(struct rte_eth_dev *dev) > if (dev == NULL) > return; > > + /* > + * for secondary process, at that point we expect device > + * to be already 'usable', so shared data and all function pointers > + * for fast-path devops have to be setup properly inside rte_eth_dev. > + */ > + if (rte_eal_process_type() == RTE_PROC_SECONDARY) > + eth_dev_fp_ops_setup(rte_eth_fp_ops + dev->data->port_id, dev); > + > rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_NEW, NULL); > > dev->state = RTE_ETH_DEV_ATTACHED; > diff --git a/lib/ethdev/rte_ethdev_core.h b/lib/ethdev/rte_ethdev_core.h > index 51cd68de94..d5853dff86 100644 > --- a/lib/ethdev/rte_ethdev_core.h > +++ b/lib/ethdev/rte_ethdev_core.h > @@ -50,6 +50,61 @@ 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 pointers to internal ethdev Rx/Tx > + * queues data. > + * The main purpose to expose these pointers at all - allow compiler > + * to fetch this data for fast-path 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-path ethdev functions and related data are hold in a flat array. > + * One entry per ethdev. > + * On 64-bit systems contents of this structure occupy exactly two 64B lines. > + * On 32-bit systems contents of this structure fits into one 64B line. > + */ > +struct rte_eth_fp_ops { > + > + /** > + * Rx fast-path functions and related data. > + * 64-bit systems: occupies first 64B line > + */ > + eth_rx_burst_t rx_pkt_burst; > + /**< PMD receive 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. */ > + struct rte_ethdev_qdata rxq; > + /**< Rx queues data. */ > + uintptr_t reserved1[3]; > + > + /** > + * Tx fast-path functions and related data. > + * 64-bit systems: occupies second 64B line > + */ > + eth_tx_burst_t tx_pkt_burst; Why not place rx_pkt_burst/tx_pkt_burst/rxq /txq to the first cacheline ? Other function, e.g. rx_queue_count/descriptor_status are low frequency call functions. > + /**< PMD transmit function. */ > + eth_tx_prep_t tx_pkt_prepare; > + /**< PMD transmit prepare function. */ > + eth_tx_descriptor_status_t tx_descriptor_status; > + /**< Check the status of a Tx descriptor. */ > + struct rte_ethdev_qdata txq; > + /**< Tx queues data. */ > + uintptr_t reserved2[3]; > + > +} __rte_cache_aligned; > + > +extern struct rte_eth_fp_ops rte_eth_fp_ops[RTE_MAX_ETHPORTS]; > + > > /** > * @internal >