75452167a2
CTB writes are now in the path of command submission and should be optimized for performance. Rather than reading CTB descriptor values (e.g. head, tail) which could result in accesses across the PCIe bus, store shadow local copies and only read/write the descriptor values when absolutely necessary. Also store the current space in the each channel locally. v2: (Michal) - Add additional sanity checks for head / tail pointers - Use GUC_CTB_HDR_LEN rather than magic 1 v3: (Michal / John H) - Drop redundant check of head value v4: (John H) - Drop redundant checks of tail / head values v5: (Michal) - Address more nits v6: (Michal) - Add GEM_BUG_ON sanity check on ctb->space Signed-off-by: John Harrison <John.C.Harrison@Intel.com> Signed-off-by: Matthew Brost <matthew.brost@intel.com> Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com> Signed-off-by: John Harrison <John.C.Harrison@Intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210708162055.129996-7-matthew.brost@intel.com
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.