mirror of
https://github.com/torvalds/linux.git
synced 2026-07-31 11:37:06 +02:00
Linux kernel source tree
92b13cabea
Tony Nguyen says: ==================== 1GbE Intel Wired LAN Driver Updates 2021-05-20 This series contains updates to igc driver only. Andre Guedes says: This series adds AF_XDP zero-copy feature to igc driver. The initial patches do some code refactoring, preparing the code base to land the AF_XDP zero-copy feature, avoiding code duplications. The last patches of the series are the ones implementing the feature. The last patch which indeed implements AF_XDP zero-copy support was originally way too lengthy so, for the sake of code review, I broke it up into two patches: one adding support for the RX functionality and the other one adding TX support. --- v2: Patch 8/9 - "igc: Enable RX via AF_XDP zero-copy" * In XDP_PASS flow, copy metadata too into the skb. * When HW timestamp is added by the NIC, after copying it into a local variable, update xdp_buff->data_meta so that metadata length when XDP program is called 0. * In igc_xdp_enable_pool(), call xsk_pool_dma_unmap() on failure. Known issues: When an XDP application is running in Tx-Only mode with Zero-Copy enabled, it is not expected to add the frames to the fill-queue. I have noticed the following two issues in this scenario: - If XDP_USE_NEED_WAKEUP flag is not set by application, igc_poll() will go into infinite loop because the buffer allocation resulting in igc_clean_rx_irq_zc() indicating that all work is not done and NAPI should keep polling. This does not occur if XDP_USE_NEED_WAKEUP flag is set. - Since there are no buffers allocated by userspace for the fill queue, there is no memory allocated for the NIC to copy the data to. If the packet received is destined to the hardware queue where XDP application is running, no packets are received even on other queues. Both these issues can be mitigated by adding a few frames to the fill queue. The second issue can also be mitigated by making sure no packets are being received on the hardware queue where Rx is running. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> |
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.