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f3cc0d2747
In the pursuit of lowering driver overhead, it became clear that some
amount of redesign of how libdrm_freedreno constructs the submit ioctl
would be needed. In particular, as the gallium driver is starting to
make heavier use of CP_SET_DRAW_STATE state groups/objects, the over-
head of tracking cmd buffers and relocs becomes too much. And for
"streaming" state, which isn't ever reused (like uniform uploads) the
overhead of allocating/freeing ringbuffer[1] objects is too high.
This redesign makes two main changes:
1) Introduces a fd_submit object for tracking bos and cmds table
for the submit ioctl, making ringbuffer objects more light-
weight. This was previously done in the ringbuffer. But we
have many ringbuffer instances involved in a submit (gmem +
draw + potentially 1000's of state-group rbs), and only need
a single bos and cmds table. (Reloc table is still per-rb)
The submit is also a convenient place for a slab allocator for
ringbuffer objects. Other options would have required locking
because, while we can guarantee allocations will only happen on
a single thread, free's could happen either on the application
thread or the flush_queue thread. With the slab allocator in
the submit object, any frees that happen on the flush_queue
thread happen after we know that the application thread is done
with the submit.
2) Introduce a new "softpin" msm_ringbuffer_sp implementation that
does not use relocs and only has cmds table entries for IB1 (ie.
the cmdstream buffers that kernel needs to CP_INDIRECT_BUFFER
to from the RB). To do this properly will require some updates
on the kernel side, so whether you get the softpin or legacy
submit/ringbuffer implementation at runtime depends on your
kernel version.
To make all these changes in libdrm would basically require adding a
libdrm_freedreno2, so this is a good point to just pull the libdrm code
into mesa. Plus it allows for using mesa's hashtable, slab allocator,
etc. And it lets us have asserts enabled for debug mesa buids but
omitted for release builds. And it makes life easier if further API
changes become necessary.
At this point I haven't tried to pull in the kgsl backend. Although
I left the level of vfunc indirection which would make it possible
to have other backends. (And this was convenient to keep to allow
for the "softpin" ringbuffer to coexist.)
NOTE: if bisecting a build error takes you here, try a clean build.
There are a bunch of ways things can go wrong if you still have
libdrm_freedreno cflags.
[1] "ringbuffer" is probably a bad name, the only level of cmdstream
buffer that is actually a ring is RB managed by kernel. User-
space cmdstream is all IB1/IB2 and state-groups.
Reviewed-by: Kristian H. Kristensen <hoegsberg@chromium.org>
Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>
Signed-off-by: Rob Clark <robdclark@gmail.com>
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| docs | ||
| doxygen | ||
| include | ||
| m4 | ||
| scons | ||
| scripts | ||
| src | ||
| .dir-locals.el | ||
| .editorconfig | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .travis.yml | ||
| Android.common.mk | ||
| Android.mk | ||
| appveyor.yml | ||
| autogen.sh | ||
| CleanSpec.mk | ||
| common.py | ||
| configure.ac | ||
| install-gallium-links.mk | ||
| install-lib-links.mk | ||
| Makefile.am | ||
| meson.build | ||
| meson_options.txt | ||
| README.rst | ||
| REVIEWERS | ||
| SConstruct | ||
| VERSION | ||
`Mesa <https://mesa3d.org>`_ - The 3D Graphics Library
======================================================
Source
------
This repository lives at https://gitlab.freedesktop.org/mesa/mesa.
Other repositories are likely forks, and code found there is not supported.
Build status
------------
Travis:
.. image:: https://travis-ci.org/mesa3d/mesa.svg?branch=master
:target: https://travis-ci.org/mesa3d/mesa
Appveyor:
.. image:: https://img.shields.io/appveyor/ci/mesa3d/mesa.svg
:target: https://ci.appveyor.com/project/mesa3d/mesa
Coverity:
.. image:: https://scan.coverity.com/projects/139/badge.svg?flat=1
:target: https://scan.coverity.com/projects/mesa
Build & install
---------------
You can find more information in our documentation (`docs/install.html
<https://mesa3d.org/install.html>`_), but the recommended way is to use
Meson (`docs/meson.html <https://mesa3d.org/meson.html>`_):
.. code-block:: sh
$ mkdir build
$ cd build
$ meson ..
$ sudo ninja install
Support
-------
Many Mesa devs hang on IRC; if you're not sure which channel is
appropriate, you should ask your question on `Freenode's #dri-devel
<irc://chat.freenode.net#dri-devel>`_, someone will redirect you if
necessary.
Remember that not everyone is in the same timezone as you, so it might
take a while before someone qualified sees your question.
To figure out who you're talking to, or which nick to ping for your
question, check out `Who's Who on IRC
<https://dri.freedesktop.org/wiki/WhosWho/>`_.
The next best option is to ask your question in an email to the
mailing lists: `mesa-dev\@lists.freedesktop.org
<https://lists.freedesktop.org/mailman/listinfo/mesa-dev>`_
Bug reports
-----------
If you think something isn't working properly, please file a bug report
(`docs/bugs.html <https://mesa3d.org/bugs.html>`_).
Contributing
------------
Contributions are welcome, and step-by-step instructions can be found in our
documentation (`docs/submittingpatches.html
<https://mesa3d.org/submittingpatches.html>`_).
Note that Mesa uses email mailing-lists for patches submission, review and
discussions.