674e78acae
[Why] Legacy cursor plane updates from drm helpers go through the full atomic codepath. A high volume of cursor updates through this slow code path can cause subsequent page-flips to skip vblank intervals since each individual update is slow. This problem is particularly noticeable for the compton compositor. [How] A fast path for cursor plane updates is added by using DRM asynchronous commit support provided by async_check and async_update. These don't do a full state/flip_done dependency stall and they don't block other commit work. However, DC still expects itself to be single-threaded for anything that can issue register writes. Screen corruption or hangs can occur if write sequences overlap. Every call that potentially perform register writes needs to be guarded for asynchronous updates to work. The dc_lock mutex was added for this. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106175 Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Acked-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> Reviewed-by Leo Li <sunpeng.li@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.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.