495de55f70
This driver takes advantage of page_pool PP_FLAG_DMA_SYNC_DEV that can help reduce the number of cache-lines that need to be flushed when doing DMA sync for_device. Due to xdp_adjust_tail can grow the area accessible to the by the CPU (can possibly write into), then max sync length *after* bpf_prog_run_xdp() needs to be taken into account. For XDP_TX action the driver is smart and does DMA-sync. When growing tail this is still safe, because page_pool have DMA-mapped the entire page size. Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://lore.kernel.org/bpf/158945336295.97035.15034759661036971024.stgit@firesoul
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.