Re: [PATCH v3] drm/xe/oa: Fix kernel doc warnings in xe_drm.h

["Dixit, Ashutosh" <ashutosh.dixit@intel.com>]

On Mon, 24 Jun 2024 13:16:56 -0700, Dixit, Ashutosh wrote:
>
> On Mon, 24 Jun 2024 13:18:20 -0700, Souza, Jose wrote:
> >
> > On Mon, 2024-06-24 at 13:04 -0700, Dixit, Ashutosh wrote:
> > > On Mon, 24 Jun 2024 05:30:37 -0700, Michal Wajdeczko wrote:
> > > >
> > >
> > > Hi Michal,
> > >
> > > And Cc: Jose below.
> > >
> > > >
> > > >
> > > > On 23.06.2024 22:31, Ashutosh Dixit wrote:
> > > > > Fix kernel doc warnings in xe_drm.h. Also eliminate private/non-abi enum
> > > > > definitions.
> > > > >
> > > > > v2: Remove __DRM_XE_PERF_TYPE_MAX since it is unused (Michal)
> > > > > v3: Also remove DRM_XE_OA_PROPERTY_MAX since it can also be eliminated (Michal)
> > > > >
> > > > > Suggested-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
> > > > > Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
> > > >
> > > > some nits below, but in general LGTM, so
> > > >
> > > > Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
> > >
> > > Thanks.
> > >
> > > >
> > > > and I'm assuming it's not too late for such uabi fixups, but better to
> > > > wait for ack from Rodrigo
> > >
> > > Copying Jose: in case Mesa were using DRM_XE_OA_PROPERTY_MAX, they can
> > > probably also use a value like 16 like we've done below in Xe (I will make
> > > this change in IGT). Mesa PR is not merged yet so should be ok I think, but
> > > they will need to make a tiny change. I am assuming as long as this all
> > > gets into 6.11 it should be ok.
> > >
> > > Jose please confirm this is ok. Thanks.
> >
> > Mesa is not using and even if were we can change it until it gets
> > merged(after KMD patches reaches drm-next).
>
> OK, thanks for the confirmation Jose.

Thanks everyone, I went ahead and merged this so that it gets into 6.11.

Thanks.
--
Ashutosh


>
> >
> > While at it, do we have any UMD using drm_xe_query_oa_units?  Because
> > Mesa don't use it, so I think it should be removed until a UMD makes use
> > of it.  So drm_xe_query_oa_units and related UAPIs could be removed.
>
> Actually we do use drm_xe_query_oa_units in gpuvis (actually
> tools/xe-perf/xe_perf_recorder.c in IGT, which is used for gpuvis OA
> recordings, see assign_oa_unit()).
>
> drm_xe_query_oa_units is needed because it defines the mapping between an
> OA unit and the hardware engines connected to that OA unit. Otherwise
> userspace has no way of knowing that information.
>
> In case of RCS, mostly you can assume that RCS is connected to OA unit
> 0. But for CCS etc. we need the query to correctly determine which OA unit
> that engine is connected to.
>
> Thanks.
> --
> Ashutosh
>
>
> >
> > >
> > > >
> > > > > ---
> > > > >  drivers/gpu/drm/xe/xe_oa.c | 3 ++-
> > > > >  include/uapi/drm/xe_drm.h  | 5 +----
> > > > >  2 files changed, 3 insertions(+), 5 deletions(-)
> > > > >
> > > > > diff --git a/drivers/gpu/drm/xe/xe_oa.c b/drivers/gpu/drm/xe/xe_oa.c
> > > > > index 4168b51cf7b5..9263ae9a864e 100644
> > > > > --- a/drivers/gpu/drm/xe/xe_oa.c
> > > > > +++ b/drivers/gpu/drm/xe/xe_oa.c
> > > > > @@ -1684,6 +1684,7 @@ static const xe_oa_user_extension_fn xe_oa_user_extension_funcs[] = {
> > > > >		[DRM_XE_OA_EXTENSION_SET_PROPERTY] = xe_oa_user_ext_set_property,
> > > > >  };
> > > > >
> > > > > +#define MAX_USER_EXTENSIONS	16
> > > >
> > > > nit: maybe it's worth to put small comment saying this is our choice to
> > > > limit number of nested user extensions we want to support (or at least
> > > > this is how I understood this)
> > > >
> > > > nit: and this doesn't really look like OA specific limitation, so maybe
> > > > it's time to promote MAX_USER_EXTENSIONS to some shared location to make
> > > > it unified across driver
> > >
> > > xe_exec_queue.c also uses a similar mechanism. But I think better to leave
> > > them separate in different modules so that each module can tweak the value
> > > to what is best for that module.
> > >
> > > Thanks.
> > > --
> > > Ashutosh
> > >
> > >
> > > >
> > > > >  static int xe_oa_user_extensions(struct xe_oa *oa, u64 extension, int ext_number,
> > > > >					 struct xe_oa_open_param *param)
> > > > >  {
> > > > > @@ -1692,7 +1693,7 @@ static int xe_oa_user_extensions(struct xe_oa *oa, u64 extension, int ext_number
> > > > >		int err;
> > > > >		u32 idx;
> > > > >
> > > > > -	if (XE_IOCTL_DBG(oa->xe, ext_number >= DRM_XE_OA_PROPERTY_MAX))
> > > > > +	if (XE_IOCTL_DBG(oa->xe, ext_number >= MAX_USER_EXTENSIONS))
> > > > >			return -E2BIG;
> > > > >
> > > > >		err = __copy_from_user(&ext, address, sizeof(ext));
> > > > > diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> > > > > index 93e00be44b2d..b410553faa9b 100644
> > > > > --- a/include/uapi/drm/xe_drm.h
> > > > > +++ b/include/uapi/drm/xe_drm.h
> > > > > @@ -1379,8 +1379,8 @@ struct drm_xe_wait_user_fence {
> > > > >   * enum drm_xe_perf_type - Perf stream types
> > > > >   */
> > > > >  enum drm_xe_perf_type {
> > > > > +	/** @DRM_XE_PERF_TYPE_OA: OA perf stream type */
> > > > >		DRM_XE_PERF_TYPE_OA,
> > > > > -	__DRM_XE_PERF_TYPE_MAX, /* non-ABI */
> > > > >  };
> > > > >
> > > > >  /**
> > > > > @@ -1611,9 +1611,6 @@ enum drm_xe_oa_property_id {
> > > > >		 * pass along with @DRM_XE_OA_PROPERTY_EXEC_QUEUE_ID or will default to 0.
> > > > >		 */
> > > > >		DRM_XE_OA_PROPERTY_OA_ENGINE_INSTANCE,
> > > > > -
> > > > > -	/** @DRM_XE_OA_PROPERTY_MAX: non-ABI */
> > > > > -	DRM_XE_OA_PROPERTY_MAX
> > > > >  };
> > > > >
> > > > >  /**
> >