Am 09.08.2016 um 15:47 schrieb Nicolai Hähnle:
Hi everybody,
addrlib is the addressing and alignment calculator which is used by
radeonsi. It's developed (and also used) internally at AMD, and so far
we've had one open source copy living in the Mesa repository at
src/gallium/winsys/amdgpu/drm/addrlib.
The question of using addrlib in non-Mesa parts of our open-source
stack has come up, in particular in relation to compute. We'd
obviously like to share the code rather than having multiple copies
flying around. Since the interface of addrlib is slow-moving but
unstable, shared linking is not an option.
I think the best way forward is to create a dedicated repository for
addrlib which is then integrated into Mesa as a git submodule.
The point of this email is to gather feedback from the Mesa community
on this plan, which is explicitly:
(0) Create an addrlib repository, say amd/addrlib on fd.o.
(1) Add it as a git submodule to the Mesa repository.
(2) Fix up whatever aspects of the build system that may be affected
(perhaps for building source tarballs).
(3) Go back to mostly ignoring addrlib, except for trying to get
better at syncing with the internal closed-source version.
From initial experiments, the impact on users interested in radeon is
that they will have to run `git submodule init` and then occasionally
`git submodule update`. Users who do not build radeonsi should be able
to ignore the change completely.
There are alternatives. For example, ROCm uses Google's repo tool
already. But for Mesa, git submodule looks like a lightweight, well
supported and overall conservative option that everybody should
already have installed. If there are good arguments for something
else, let's hear them!
Another point: if we proceed with this plan, I think we should
consider moving addrlib into src/amd/addrlib. There are two reasons:
First, transitioning to a submodule *without* changing the directory
is probably more fragile, i.e. what happens when you switch between
checkouts before and after the transition. Second, if/when radv ends
up being merged into Mesa master, it makes sense to have addrlib there
anyway.
Thoughts? Complaints? Praise?
Well using git submodule is a possibility and we had rather good
experience with that in GStreamer.
But it would remove one major argument to beating the addrlib guys
towards a stable interface and/or proper library version handling.
Moving it into libdrm is clearly not an option because then you would
need to use versioning for the whole libdrm_amdgpu library which we
don't want.
Christian.
Nicolai
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/mesa-dev
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/mesa-dev
