Re: [PATCH v3 0/7] drm: fdinfo memory stats

Christian König
2023-04-12T12:24:31Z

Am 12.04.23 um 14:10 schrieb Tvrtko Ursulin:
>
> On 12/04/2023 10:34, Christian König wrote:
>> Am 12.04.23 um 00:56 schrieb Rob Clark:
>>> From: Rob Clark <robdclark@chromium.org>
>>>
>>> Similar motivation to other similar recent attempt[1].  But with an
>>> attempt to have some shared code for this.  As well as documentation.
>>>
>>> It is probably a bit UMA-centric, I guess devices with VRAM might want
>>> some placement stats as well.  But this seems like a reasonable start.
>>>
>>> Basic gputop support: https://patchwork.freedesktop.org/series/116236/
>>> And already nvtop support: https://github.com/Syllo/nvtop/pull/204
>>>
>>> [1] https://patchwork.freedesktop.org/series/112397/
>>
>> I think the extra client id looks a bit superfluous since the ino of
>> the file should already be unique and IIRC we have been already using
>> that one.
>
> Do you mean file_inode(struct drm_file->filp)->i_ino ? That one would
> be the same number for all clients which open the same device node so
> wouldn't work.

Ah, right. DMA-buf used a separate ino per buffer, but we don't do that
for the drm_file.

>
> I also don't think the atomic_add_return for client id works either,
> since it can alias on overflow.

Yeah, we might want to use a 64bit number here if any.

Christian.

>
> In i915 I use an xarray and __xa_alloc_cyclic.
>
> Regards,
>
> Tvrtko