Re: [PATCH 2/7] drm/xe: Add ring address to LRC snapshot

[Matthew Brost <matthew.brost@intel.com>]

On Fri, Nov 08, 2024 at 03:05:34PM -0700, Cavitt, Jonathan wrote:
> -----Original Message-----
> From: Intel-xe <intel-xe-bounces@lists.freedesktop.org> On Behalf Of Matthew Brost
> Sent: Friday, November 8, 2024 9:43 AM
> To: intel-xe@lists.freedesktop.org
> Cc: Teres Alexis, Alan Previn <alan.previn.teres.alexis@intel.com>; Dong, Zhanjun <zhanjun.dong@intel.com>; Vivi, Rodrigo <rodrigo.vivi@intel.com>
> Subject: [PATCH 2/7] drm/xe: Add ring address to LRC snapshot
> > 
> > The ring is currently in LRC BO but this may change going forward.
> > Include the ring address in the snapshot protecting again any future
> > changes.
> > 
> > Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> 
> LGTM, though the terminology we're using to describe the various ggtt addresses
> as "descriptors" is a bit confusing, even if it's consistent.  I wonder where that
> terminology came from?
> This is just a rhetorical question.  I'm not suggesting it be changed.
> 

LRC descriptors is name copied over from i915 and may even be in the bspec.

But yea, indirect_state_desc and ring_desc are bad names. Will change to
'ring_addr' here.

Matt

> Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
> -Jonathan Cavitt
> 
> > ---
> >  drivers/gpu/drm/xe/xe_lrc.c | 3 +++
> >  drivers/gpu/drm/xe/xe_lrc.h | 1 +
> >  2 files changed, 4 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/xe/xe_lrc.c b/drivers/gpu/drm/xe/xe_lrc.c
> > index e219657535cf..afb0f4f44748 100644
> > --- a/drivers/gpu/drm/xe/xe_lrc.c
> > +++ b/drivers/gpu/drm/xe/xe_lrc.c
> > @@ -1636,6 +1636,7 @@ struct xe_lrc_snapshot *xe_lrc_snapshot_capture(struct xe_lrc *lrc)
> >  		xe_vm_get(lrc->bo->vm);
> >  
> >  	snapshot->context_desc = xe_lrc_ggtt_addr(lrc);
> > +	snapshot->ring_desc = __xe_lrc_ring_ggtt_addr(lrc);
> >  	snapshot->indirect_context_desc = xe_lrc_indirect_ring_ggtt_addr(lrc);
> >  	snapshot->head = xe_lrc_ring_head(lrc);
> >  	snapshot->tail.internal = lrc->ring.tail;
> > @@ -1693,6 +1694,8 @@ void xe_lrc_snapshot_print(struct xe_lrc_snapshot *snapshot, struct drm_printer
> >  		return;
> >  
> >  	drm_printf(p, "\tHW Context Desc: 0x%08x\n", snapshot->context_desc);
> > +	drm_printf(p, "\tHW Ring: 0x%08x\n",
> > +		   snapshot->ring_desc);
> >  	drm_printf(p, "\tHW Indirect Ring State: 0x%08x\n",
> >  		   snapshot->indirect_context_desc);
> >  	drm_printf(p, "\tLRC Head: (memory) %u\n", snapshot->head);
> > diff --git a/drivers/gpu/drm/xe/xe_lrc.h b/drivers/gpu/drm/xe/xe_lrc.h
> > index 9d64cedc4d14..a2058a501353 100644
> > --- a/drivers/gpu/drm/xe/xe_lrc.h
> > +++ b/drivers/gpu/drm/xe/xe_lrc.h
> > @@ -25,6 +25,7 @@ struct xe_lrc_snapshot {
> >  	unsigned long lrc_size, lrc_offset;
> >  
> >  	u32 context_desc;
> > +	u32 ring_desc;
> >  	u32 indirect_context_desc;
> >  	u32 head;
> >  	struct {
> > -- 
> > 2.34.1
> > 
> >