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 417824286D; Thu, 30 Mar 2023 08:29:50 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 01EE440E25; Thu, 30 Mar 2023 08:29:50 +0200 (CEST) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by mails.dpdk.org (Postfix) with ESMTP id A686740685 for ; Thu, 30 Mar 2023 08:29:48 +0200 (CEST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5D9862F4; Wed, 29 Mar 2023 23:30:32 -0700 (PDT) Received: from net-x86-dell-8268.shanghai.arm.com (net-x86-dell-8268.shanghai.arm.com [10.169.210.116]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 2ABA63F663; Wed, 29 Mar 2023 23:29:45 -0700 (PDT) From: Feifei Wang To: Cc: dev@dpdk.org, konstantin.v.ananyev@yandex.ru, mb@smartsharesystems.com, nd@arm.com, Feifei Wang Subject: [PATCH v5 0/3] Recycle buffers from Tx to Rx Date: Thu, 30 Mar 2023 14:29:36 +0800 Message-Id: <20230330062939.1206267-1-feifei.wang2@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211224164613.32569-1-feifei.wang2@arm.com> References: <20211224164613.32569-1-feifei.wang2@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 Currently, the transmit side frees the buffers into the lcore cache and the receive side allocates buffers from the lcore cache. The transmit side typically frees 32 buffers resulting in 32*8=256B of stores to lcore cache. The receive side allocates 32 buffers and stores them in the receive side software ring, resulting in 32*8=256B of stores and 256B of load from the lcore cache. This patch proposes a mechanism to avoid freeing to/allocating from the lcore cache. i.e. the receive side will free the buffers from transmit side directly into its software ring. This will avoid the 256B of loads and stores introduced by the lcore cache. It also frees up the cache lines used by the lcore cache. And we can call this mode as buffer recycle mode. In the latest version, buffer recycle mode is packaged as a separate API. This allows for the users to change rxq/txq pairing in real time in data plane, according to the analysis of the packet flow by the application, for example: ----------------------------------------------------------------------- Step 1: upper application analyse the flow direction Step 2: rxq_buf_recycle_info = rte_eth_rx_buf_recycle_info_get(rx_portid, rx_queueid) Step 3: rte_eth_dev_buf_recycle(rx_portid, rx_queueid, tx_portid, tx_queueid, rxq_buf_recycle_info); Step 4: rte_eth_rx_burst(rx_portid,rx_queueid); Step 5: rte_eth_tx_burst(tx_portid,tx_queueid); ----------------------------------------------------------------------- Above can support user to change rxq/txq pairing at runtime and user does not need to know the direction of flow in advance. This can effectively expand buffer recycle mode's use scenarios. Furthermore, buffer recycle mode is no longer limited to the same pmd, it can support moving buffers between different vendor pmds, even can put the buffer anywhere into your Rx buffer ring as long as the address of the buffer ring can be provided. In the latest version, we enable direct-rearm in i40e pmd and ixgbe pmd, and also try to use i40e driver in Rx, ixgbe driver in Tx, and then achieve 7-9% performance improvement by buffer recycle mode. Difference between buffer recycle, ZC API used in mempool and general path For general path: Rx: 32 pkts memcpy from mempool cache to rx_sw_ring Tx: 32 pkts memcpy from tx_sw_ring to temporary variable + 32 pkts memcpy from temporary variable to mempool cache For ZC API used in mempool: Rx: 32 pkts memcpy from mempool cache to rx_sw_ring Tx: 32 pkts memcpy from tx_sw_ring to zero-copy mempool cache Refer link: http://patches.dpdk.org/project/dpdk/patch/20230221055205.22984-2-kamalakshitha.aligeri@arm.com/ For buffer recycle: Rx/Tx: 32 pkts memcpy from tx_sw_ring to rx_sw_ring Thus we can see in the one loop, compared to general path, buffer recycle reduce 32+32=64 pkts memcpy; Compared to ZC API used in mempool, we can see buffer recycle reduce 32 pkts memcpy in each loop. So, buffer recycle has its own benefits. Testing status: (1) dpdk l3fwd test with multiple drivers: port 0: 82599 NIC port 1: XL710 NIC ------------------------------------------------------------- Without fast free With fast free Thunderx2: +7.53% +13.54% ------------------------------------------------------------- (2) dpdk l3fwd test with same driver: port 0 && 1: XL710 NIC ------------------------------------------------------------- Without fast free With fast free Ampere altra: +12.61% +11.42% n1sdp: +8.30% +3.85% x86-sse: +8.43% +3.72% ------------------------------------------------------------- (3) Performance comparison with ZC_mempool used port 0 && 1: XL710 NIC with fast free ------------------------------------------------------------- With recycle buffer With zc_mempool Ampere altra: 11.42% 3.54% ------------------------------------------------------------- V2: 1. Use data-plane API to enable direct-rearm (Konstantin, Honnappa) 2. Add 'txq_data_get' API to get txq info for Rx (Konstantin) 3. Use input parameter to enable direct rearm in l3fwd (Konstantin) 4. Add condition detection for direct rearm API (Morten, Andrew Rybchenko) V3: 1. Seperate Rx and Tx operation with two APIs in direct-rearm (Konstantin) 2. Delete L3fwd change for direct rearm (Jerin) 3. enable direct rearm in ixgbe driver in Arm v4: 1. Rename direct-rearm as buffer recycle. Based on this, function name and variable name are changed to let this mode more general for all drivers. (Konstantin, Morten) 2. Add ring wrapping check (Konstantin) v5: 1. some change for ethdev API (Morten) 2. add support for avx2, sse, altivec path Feifei Wang (3): ethdev: add API for buffer recycle mode net/i40e: implement recycle buffer mode net/ixgbe: implement recycle buffer mode drivers/net/i40e/i40e_ethdev.c | 1 + drivers/net/i40e/i40e_ethdev.h | 2 + drivers/net/i40e/i40e_rxtx.c | 159 +++++++++++++++++++++ drivers/net/i40e/i40e_rxtx.h | 4 + drivers/net/ixgbe/ixgbe_ethdev.c | 1 + drivers/net/ixgbe/ixgbe_ethdev.h | 3 + drivers/net/ixgbe/ixgbe_rxtx.c | 153 ++++++++++++++++++++ drivers/net/ixgbe/ixgbe_rxtx.h | 4 + lib/ethdev/ethdev_driver.h | 10 ++ lib/ethdev/ethdev_private.c | 2 + lib/ethdev/rte_ethdev.c | 33 +++++ lib/ethdev/rte_ethdev.h | 230 +++++++++++++++++++++++++++++++ lib/ethdev/rte_ethdev_core.h | 15 +- lib/ethdev/version.map | 6 + 14 files changed, 621 insertions(+), 2 deletions(-) -- 2.25.1