Re: [RFC PATCH] drm/xe/uapi: Remove support for persistent exec_queues

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Tue, Jan 30, 2024 at 08:24:07AM -0600, Lucas De Marchi wrote:
> On Tue, Jan 30, 2024 at 01:52:20PM +0100, Thomas Hellström wrote:
> > Persistent exec_queues delays explicit destruction of exec_queues
> > until they are done executing, but destruction on process exit
> > is still immediate. It turns out no UMD is relying on this
> > functionality, so remove it. If there turns out to be a use-case
> > in the future, let's re-add.
> > 
> > Persistent exec_queues were never used for LR VMs
> > 
> > Open: Should we renumber the exec_queue properties, or leave a hole
> > as in this patch.
> 
> I think it's fine to leave a hole
> 
> > diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> > index 50bbea0992d9..4124284e4cce 100644
> > --- a/include/uapi/drm/xe_drm.h
> > +++ b/include/uapi/drm/xe_drm.h
> > @@ -1045,7 +1045,7 @@ struct drm_xe_exec_queue_create {
> > #define   DRM_XE_EXEC_QUEUE_SET_PROPERTY_PRIORITY		0
> > #define   DRM_XE_EXEC_QUEUE_SET_PROPERTY_TIMESLICE		1
> > #define   DRM_XE_EXEC_QUEUE_SET_PROPERTY_PREEMPTION_TIMEOUT	2
> > -#define   DRM_XE_EXEC_QUEUE_SET_PROPERTY_PERSISTENCE		3
> > +#define   DRM_XE_EXEC_QUEUE_SET_UNUSED_1		        3
> 
> but I don't think we should add this define here. We could eventually
> just use this whole.

Leave the hole and the define and then add checks to refuse the ioctl
if this property number is selected.

> 
> 
> 
> Lucas De Marchi