[PATCH 0/3] Deferr load of radeon/amdgpu until amdkfd is loaded

[Oded Gabbay]

On Sun, Feb 14, 2016 at 2:58 PM, Daniel Vetter <daniel at ffwll.ch> wrote:
> On Sun, Feb 14, 2016 at 11:16:52AM +0200, Oded Gabbay wrote:
>> Following Daniel's request, I spent some time removing the hard requirement
>> that radeon and amdgpu will always appear _after_ amdkfd in the drm Makefile.
>>
>> This was done by modifing radeon/amdgpu to defer their loading if they detect
>> that amdkfd is not loaded yet, in case the drivers are built inside the
>> kernel image.
>>
>> See the patch's individiual commit messages for more explanation.
>>
>> This patch-set was tested on a KAVERI machine, with multiple configurations:
>>
>> 1. radeon + amdgpu (CIK disabled) + amdkfd as kernel modules
>> 2. radeon + amdgpu (CIK disabled) + amdkfd inside the kernel image
>> 3. amdgpu (CIK enabled) + amdkfd inside the kernel image (radeon not compiled)
>> 4. amdgpu (CIK enabled) inside the kernel image (radeon + amdkfd not compiled)
>> 5. radeon + amdgpu (CIK disabled) as kernel modules (amdkfd not compiled)
>
> Care to throw one patch on top (maybe on top of the patch floating around)
> to reorder amdkfd to be alphabetical? Just to make sure this doesn't get
> broken again accidentally. Or maybe just pick up the other patch and adapt
> it so it's all in one series.
>
> Thanks, Daniel

Hi Daniel,

I thought about it and I think I prefer to leave the current order as
it is, for the reason that I observed the boot-up process is a little
bit faster when the deferred probing doesn't occur. This is probably
because all the moves between pending drivers list and active driver
list.

Although this patch-set ensure that the kernel will boot successfully
with no regard to the order of amdkfd/radeon/amdgpu in the drm
makefile, I think that if the current order gives us a bit less boot
time then it is better to keep things as they are.

Thanks,

      Oded

>>
>> Thanks,
>>
>>     Oded
>>
>> Oded Gabbay (3):
>>   drm/amdkfd: Track when module's init is complete
>>   drm/radeon: Return -EPROBE_DEFER when amdkfd not loaded
>>   drm/amdgpu: Return -EPROBE_DEFER when amdkfd not loaded
>>
>>  drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c      | 57 +++++++++----------------
>>  drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h      |  2 +-
>>  drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c         | 10 ++++-
>>  drivers/gpu/drm/amd/amdkfd/kfd_module.c         | 15 +++++--
>>  drivers/gpu/drm/amd/include/kgd_kfd_interface.h |  2 +-
>>  drivers/gpu/drm/radeon/radeon_drv.c             | 10 ++++-
>>  drivers/gpu/drm/radeon/radeon_kfd.c             | 25 ++++++-----
>>  drivers/gpu/drm/radeon/radeon_kfd.h             |  2 +-
>>  8 files changed, 64 insertions(+), 59 deletions(-)
>>
>> --
>> 2.5.0
>>
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch