Re: [PATCH 3/3] drm: omapdrm: Do no allocate non-scanout GEMs through DMM/TILER

[Tomi Valkeinen]

Hi,

On 19/01/2022 12:23, Ivaylo Dimitrov wrote:
> On devices with DMM, all allocations are done through either DMM or TILER.
> DMM/TILER being a limited resource means that such allocations will start
> to fail before actual free memory is exhausted. What is even worse is that
> with time DMM/TILER space gets fragmented to the point that even if we have
> enough free DMM/TILER space and free memory, allocation fails because there
> is no big enough free block in DMM/TILER space.
>
> Such failures can be easily observed with OMAP xorg DDX, for example -
> starting few GUI applications (so buffers for their windows are allocated)
> and then rotating landscape<->portrait while closing and opening new
> windows soon results in allocation failures.
>
> Fix that by mapping buffers through DMM/TILER only when really needed,
> like, for scanout buffers.

Doesn't this break users that get a buffer from omapdrm and expect it to 
be contiguous?

 Tomi