[PATCH RFC 0/2] Re: Deprecation of AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED

[John Brooks]

> On 30/06/17 03:59 PM, Christian König wrote:
>> Am 30.06.2017 um 08:51 schrieb Michel Dänzer:
>>> We can deal with that internally in the kernel, while fixing the
>>> existing flag for userspace.
>> And as I said, NAK to that approach. I'm not going to add a
>> CPU_ACCESS_REALLY_REQUIRED flag in the kernel just because mesa has
>> messed up it's use case.
>>
>> We could agree on filtering that flag from userspace when BOs are
>> created and/or map it to a CREATE_CPU_ACCESS_HINT flag.
> Then I propose the following:
>
> One patch:
>
> Convert AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED to a kernel internal flag
> AMDGPU_GEM_CPU_ACCESS_HINT in amdgpu_gem_create_ioctl, which is
> initially treated the same way as AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED.
>
> Another patch:
>
> Change the treatment of AMDGPU_GEM_CPU_ACCESS_HINT according to John's
> patch 4 in the latest series, or a variation of that as discussed on IRC.
>
>
> If any regressions are reported, we will be able to differentiate
> whether they are due to the addition of the new flag itself or due to
> the change in its handling.
>

How about this?
Note: I haven't tested this beyond compiling.

See replies for:
[PATCH RFC 1/2] drm/amdgpu: Add AMDGPU_BO_FLAG_CPU_ACCESS
[PATCH RFC 2/2] drm/amdgpu: Set/clear CPU_ACCESS flag on page fault

John

>
> -- 
> Earthling Michel Dänzer               |               http://www.amd.com
> Libre software enthusiast             |             Mesa and X developer