d1396004dd
This allows further redirection of xdp_frames like NIC -> veth--veth -> veth--veth (XDP) (XDP) (XDP) The intermediate XDP, redirecting packets from NIC to the other veth, reuses xdp_mem_info from NIC so that page recycling of the NIC works on the destination veth's XDP. In this way return_frame is not fully guarded by NAPI, since another NAPI handler on another cpu may use the same xdp_mem_info concurrently. Thus disable napi_direct by xdp_set_return_frame_no_direct() during the NAPI context. v8: - Don't use xdp_frame pointer address for data_hard_start of xdp_buff. v4: - Use xdp_[set|clear]_return_frame_no_direct() instead of a flag in xdp_mem_info. v3: - Fix double free when veth_xdp_tx() returns a positive value. - Convert xdp_xmit and xdp_redir variables into flags. Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.