FreeBSD source tree https://cgit-dev.freebsd.org/src/atom?h=releng%2F12.0 2017-05-22T14:46:13Z 2017-05-22T14:46:13Z Zbigniew Bodek zbb@FreeBSD.org 2017-05-22T14:46:13Z urn:sha1:9b8d05b8ac78509e8c4b9f6f1e71c873b38a06b9 ENA is a networking interface designed to make good use of modern CPU features and system architectures. The ENA device exposes a lightweight management interface with a minimal set of memory mapped registers and extendable command set through an Admin Queue. The driver supports a range of ENA devices, is link-speed independent (i.e., the same driver is used for 10GbE, 25GbE, 40GbE, etc.), and has a negotiated and extendable feature set. Some ENA devices support SR-IOV. This driver is used for both the SR-IOV Physical Function (PF) and Virtual Function (VF) devices. ENA devices enable high speed and low overhead network traffic processing by providing multiple Tx/Rx queue pairs (the maximum number is advertised by the device via the Admin Queue), a dedicated MSI-X interrupt vector per Tx/Rx queue pair, and CPU cacheline optimized data placement. The ENA driver supports industry standard TCP/IP offload features such as checksum offload and TCP transmit segmentation offload (TSO). Receive-side scaling (RSS) is supported for multi-core scaling. The ENA driver and its corresponding devices implement health monitoring mechanisms such as watchdog, enabling the device and driver to recover in a manner transparent to the application, as well as debug logs. Some of the ENA devices support a working mode called Low-latency Queue (LLQ), which saves several more microseconds. This feature will be implemented for driver in future releases. Submitted by: Michal Krawczyk <mk@semihalf.com> Jakub Palider <jpa@semihalf.com> Jan Medala <jan@semihalf.com> Obtained from: Semihalf Sponsored by: Amazon.com Inc. Differential revision: https://reviews.freebsd.org/D10427