From: Jakub Kicinski Date: Wed, 18 Jun 2025 01:34:15 +0000 (-0700) Subject: Merge branch 'net-mlx5e-add-support-for-devmem-and-io_uring-tcp-zero-copy' X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8152c4028cb8b69933ebb93e7b0cc58bc47dfb2e;p=thirdparty%2Flinux.git Merge branch 'net-mlx5e-add-support-for-devmem-and-io_uring-tcp-zero-copy' Mark Bloch says: ==================== net/mlx5e: Add support for devmem and io_uring TCP zero-copy This series adds support for zerocopy rx TCP with devmem and io_uring for ConnectX7 NICs and above. For performance reasons and simplicity HW-GRO will also be turned on when header-data split mode is on. Performance =========== Test setup: * CPU: Intel(R) Xeon(R) Platinum 8380 CPU @ 2.30GHz (single NUMA) * NIC: ConnectX7 * Benchmarking tool: kperf [0] * Single TCP flow * Test duration: 60s With application thread and interrupts pinned to the *same* core: |------+-----------+----------| | MTU | epoll | io_uring | |------+-----------+----------| | 1500 | 61.6 Gbps | 114 Gbps | | 4096 | 69.3 Gbps | 151 Gbps | | 9000 | 67.8 Gbps | 187 Gbps | |------+-----------+----------| The CPU usage for io_uring is 95%. Reproduction steps for io_uring: server --no-daemon -a 2001:db8::1 --no-memcmp --iou --iou_sendzc \ --iou_zcrx --iou_dev_name eth2 --iou_zcrx_queue_id 2 server --no-daemon -a 2001:db8::2 --no-memcmp --iou --iou_sendzc client --src 2001:db8::2 --dst 2001:db8::1 \ --msg-zerocopy -t 60 --cpu-min=2 --cpu-max=2 Patch overview: ================ First, a netmem API for skb_can_coalesce is added to the core to be able to do skb fragment coalescing on netmems. The next patches introduce some cleanups in the internal SHAMPO code and improvements to hw gro capability checks in FW. A separate page_pool is introduced for headers, to be used only when the rxq has a memory provider. Then the driver is converted to use the netmem API and to allow support for unreadable netmem page pool. The queue management ops are implemented. Finally, the tcp-data-split ring parameter is exposed. References ========== [0] kperf: git://git.kernel.dk/kperf.git v1: https://lore.kernel.org/20250116215530.158886-1-saeed@kernel.org v2: https://lore.kernel.org/1747950086-1246773-1-git-send-email-tariqt@nvidia.com v3: https://lore.kernel.org/20250609145833.990793-1-mbloch@nvidia.com v4: https://lore.kernel.org/20250610150950.1094376-1-mbloch@nvidia.com v5: https://lore.kernel.org/20250612154648.1161201-1-mbloch@nvidia.com ==================== Link: https://patch.msgid.link/20250616141441.1243044-1-mbloch@nvidia.com Signed-off-by: Jakub Kicinski --- 8152c4028cb8b69933ebb93e7b0cc58bc47dfb2e