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

[Christian König]

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@xxxxxxxxxxxx>
> > >
> > > 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