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 CD0E043747; Tue, 19 Dec 2023 18:30:31 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id B2AA342E11; Tue, 19 Dec 2023 18:30:31 +0100 (CET) Received: from mx0b-0016f401.pphosted.com (mx0b-0016f401.pphosted.com [67.231.156.173]) by mails.dpdk.org (Postfix) with ESMTP id 864F442DED for ; Tue, 19 Dec 2023 18:30:29 +0100 (CET) Received: from pps.filterd (m0045851.ppops.net [127.0.0.1]) by mx0b-0016f401.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 3BJ9k0Oj015977; Tue, 19 Dec 2023 09:30:16 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=marvell.com; h= from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding:content-type; s=pfpt0220; bh=KNOJ6TnH NGIm0x7xYraxkvRWxyv+WwZPwgPvPTa/1N0=; b=BbMfmiuOTxC7UQViUSeXlRRP mD5f+XroDVgpLZEmHpYhO3+wB5WPSf7eg0hEajoJ7mOmygtPmnVIQNDvZeUbjmD2 PuKafgzUqqy0ODs8Hx4AVJt9dRkIj0gLPKTEYI+UeCyvM2fObk8f40TlRNRk7I7B dQLr6oQED8/zRcr4rBms8AcQWszMK1RW/0+s1GyUe/VckcvGuuYDLNdqqmm3o+x2 S95UyR+vzM6p+uAZl85Zbk7Dvf/hmSTKixgnEfy1HJdWvJVMbNQYi2SY742zXYcg eeBFDwdijcdiszMGroR2zsjA0yAu6aXnVRnCwqJfbRt4o/b0qjPugVHpg+LjoA== Received: from dc5-exch02.marvell.com ([199.233.59.182]) by mx0b-0016f401.pphosted.com (PPS) with ESMTPS id 3v1c9kuk3v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Tue, 19 Dec 2023 09:30:15 -0800 (PST) Received: from DC5-EXCH02.marvell.com (10.69.176.39) by DC5-EXCH02.marvell.com (10.69.176.39) with Microsoft SMTP Server (TLS) id 15.0.1497.48; Tue, 19 Dec 2023 09:30:13 -0800 Received: from maili.marvell.com (10.69.176.80) by DC5-EXCH02.marvell.com (10.69.176.39) with Microsoft SMTP Server id 15.0.1497.48 via Frontend Transport; Tue, 19 Dec 2023 09:30:13 -0800 Received: from jerin-lab.marvell.com (jerin-lab.marvell.com [10.28.34.14]) by maili.marvell.com (Postfix) with ESMTP id 7CB903F7050; Tue, 19 Dec 2023 09:29:53 -0800 (PST) From: To: , Thomas Monjalon , Ferruh Yigit , Andrew Rybchenko CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Jerin Jacob Subject: [dpdk-dev] [RFC] ethdev: support Tx queue free descriptor query Date: Tue, 19 Dec 2023 22:59:48 +0530 Message-ID: <20231219172948.3909749-1-jerinj@marvell.com> X-Mailer: git-send-email 2.43.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Proofpoint-ORIG-GUID: F7dEyzIlhO7HQPha4MOb2xRKRYcbnYZR X-Proofpoint-GUID: F7dEyzIlhO7HQPha4MOb2xRKRYcbnYZR X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-12-09_02,2023-12-07_01,2023-05-22_02 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 From: Jerin Jacob Introduce a new API to retrieve the number of available free descriptors in a Tx queue. Applications can leverage this API in the fast path to inspect the Tx queue occupancy and take appropriate actions based on the available free descriptors. A notable use case could be implementing Random Early Discard (RED) in software based on Tx queue occupancy. Signed-off-by: Jerin Jacob --- doc/guides/nics/features.rst | 10 ++++ doc/guides/nics/features/default.ini | 1 + lib/ethdev/ethdev_trace_points.c | 3 ++ lib/ethdev/rte_ethdev.h | 78 ++++++++++++++++++++++++++++ lib/ethdev/rte_ethdev_core.h | 7 ++- lib/ethdev/rte_ethdev_trace_fp.h | 8 +++ 6 files changed, 106 insertions(+), 1 deletion(-) diff --git a/doc/guides/nics/features.rst b/doc/guides/nics/features.rst index f7d9980849..9d6655473a 100644 --- a/doc/guides/nics/features.rst +++ b/doc/guides/nics/features.rst @@ -962,6 +962,16 @@ management (see :doc:`../prog_guide/power_man` for more details). * **[implements] eth_dev_ops**: ``get_monitor_addr`` +.. _nic_features_tx_queue_free_desc_query: + +Tx queue free descriptor query +------------------------------ + +Supports to get the number of free descriptors in a Tx queue. + +* **[implements] eth_dev_ops**: ``tx_queue_free_desc_get``. +* **[related] API**: ``rte_eth_tx_queue_free_desc_get()``. + .. _nic_features_other: Other dev ops not represented by a Feature diff --git a/doc/guides/nics/features/default.ini b/doc/guides/nics/features/default.ini index 806cb033ff..b30002b1c1 100644 --- a/doc/guides/nics/features/default.ini +++ b/doc/guides/nics/features/default.ini @@ -59,6 +59,7 @@ Packet type parsing = Timesync = Rx descriptor status = Tx descriptor status = +Tx free descriptor query = Basic stats = Extended stats = Stats per queue = diff --git a/lib/ethdev/ethdev_trace_points.c b/lib/ethdev/ethdev_trace_points.c index 91f71d868b..346f37f2e4 100644 --- a/lib/ethdev/ethdev_trace_points.c +++ b/lib/ethdev/ethdev_trace_points.c @@ -481,6 +481,9 @@ RTE_TRACE_POINT_REGISTER(rte_eth_trace_count_aggr_ports, RTE_TRACE_POINT_REGISTER(rte_eth_trace_map_aggr_tx_affinity, lib.ethdev.map_aggr_tx_affinity) +RTE_TRACE_POINT_REGISTER(rte_eth_trace_tx_queue_free_desc_get, + lib.ethdev.tx_queue_free_desc_get) + RTE_TRACE_POINT_REGISTER(rte_flow_trace_copy, lib.ethdev.flow.copy) diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h index 77331ce652..033fcb8c9b 100644 --- a/lib/ethdev/rte_ethdev.h +++ b/lib/ethdev/rte_ethdev.h @@ -6802,6 +6802,84 @@ rte_eth_recycle_mbufs(uint16_t rx_port_id, uint16_t rx_queue_id, __rte_experimental int rte_eth_buffer_split_get_supported_hdr_ptypes(uint16_t port_id, uint32_t *ptypes, int num); +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the number of free descriptors in a Tx queue. + * + * This function retrieves the number of available free descriptors in a + * transmit queue. Applications can use this API in the fast path to inspect + * Tx queue occupancy and take appropriate actions based on the available + * free descriptors. An example action could be implementing the + * Random Early Discard (RED). + * + * If there are no packets in the Tx queue, the function returns the value + * of `nb_tx_desc` provided during the initialization of the Tx queue using + * rte_eth_tx_queue_setup(), signifying that all descriptors are free. + * + * @param port_id + * The port identifier of the device. + * @param tx_queue_id + * The index of the transmit queue. + * The value must be in the range [0, nb_tx_queue - 1] previously supplied + * to rte_eth_dev_configure(). + * @return + * - (<= UINT16_MAX) Number of free descriptors in a Tx queue + * - (> UINT16_MAX) if error. Enabled only when RTE_ETHDEV_DEBUG_TX is enabled + * + * @note This function is designed for fast-path use. + * + */ +__rte_experimental +static inline uint32_t +rte_eth_tx_queue_free_desc_get(uint16_t port_id, uint16_t tx_queue_id) +{ + struct rte_eth_fp_ops *fops; + uint32_t rc; + void *qd; + +#ifdef RTE_ETHDEV_DEBUG_TX + rc = UINT32_MAX; + if (port_id >= RTE_MAX_ETHPORTS || tx_queue_id >= RTE_MAX_QUEUES_PER_PORT) { + RTE_ETHDEV_LOG(ERR, "Invalid port_id=%u or tx_queue_id=%u\n", + port_id, tx_queue_id); + + rte_eth_trace_tx_queue_free_desc_get(port_id, tx_queue_id, rc); + return rc; + } +#endif + + /* Fetch pointer to Tx queue data */ + fops = &rte_eth_fp_ops[port_id]; + qd = fops->txq.data[tx_queue_id]; + +#ifdef RTE_ETHDEV_DEBUG_TX + RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, 0); + + if (qd == NULL) { + RTE_ETHDEV_LOG(ERR, "Invalid Tx queue_id=%u for port_id=%u\n", + tx_queue_id, port_id); + + rte_eth_trace_tx_queue_free_desc_get(port_id, tx_queue_id, rc); + return rc; + } + + if (fops->tx_queue_free_desc_get == NULL) { + RTE_ETHDEV_LOG(ERR, "tx_queue_free_desc_get callback not implementedd Tx queue_id=%u for port_id=%u\n", + tx_queue_id, port_id); + + rte_eth_trace_tx_queue_free_desc_get(port_id, tx_queue_id, rc); + return rc; + } +#endif + rc = fops->tx_queue_free_desc_get(qd); + + rte_eth_trace_tx_queue_free_desc_get(port_id, tx_queue_id, rc); + + return rc; +} + #ifdef __cplusplus } #endif diff --git a/lib/ethdev/rte_ethdev_core.h b/lib/ethdev/rte_ethdev_core.h index 4bfaf79c6c..5b7ee66ee7 100644 --- a/lib/ethdev/rte_ethdev_core.h +++ b/lib/ethdev/rte_ethdev_core.h @@ -60,6 +60,9 @@ typedef uint16_t (*eth_recycle_tx_mbufs_reuse_t)(void *txq, /** @internal Refill Rx descriptors with the recycling mbufs */ typedef void (*eth_recycle_rx_descriptors_refill_t)(void *rxq, uint16_t nb); +/** @internal Get the number of free descriptors count of a Tx queue */ +typedef uint16_t (*eth_tx_queue_free_desc_get_t)(void *txq); + /** * @internal * Structure used to hold opaque pointers to internal ethdev Rx/Tx @@ -116,7 +119,9 @@ struct rte_eth_fp_ops { eth_tx_descriptor_status_t tx_descriptor_status; /** Copy used mbufs from Tx mbuf ring into Rx. */ eth_recycle_tx_mbufs_reuse_t recycle_tx_mbufs_reuse; - uintptr_t reserved2[2]; + /** Get the number of free descriptors count of a Tx queue. */ + eth_tx_queue_free_desc_get_t tx_queue_free_desc_get; + uintptr_t reserved2[1]; /**@}*/ } __rte_cache_aligned; diff --git a/lib/ethdev/rte_ethdev_trace_fp.h b/lib/ethdev/rte_ethdev_trace_fp.h index 186271c9ff..2c57b39bd2 100644 --- a/lib/ethdev/rte_ethdev_trace_fp.h +++ b/lib/ethdev/rte_ethdev_trace_fp.h @@ -73,6 +73,14 @@ RTE_TRACE_POINT_FP( rte_trace_point_emit_u64(count); ) +RTE_TRACE_POINT_FP( + rte_eth_trace_tx_queue_free_desc_get, + RTE_TRACE_POINT_ARGS(uint16_t port_id, uint16_t tx_queue_id, uint32_t nb_free_desc), + rte_trace_point_emit_u16(port_id); + rte_trace_point_emit_u16(tx_queue_id); + rte_trace_point_emit_u32(nb_free_desc); +) + #ifdef __cplusplus } #endif -- 2.43.0