[PATCH] drm/xe/xe_gt_debugfs: Add synchronous gt reset debugfs

[Cavitt, Jonathan]

-----Original Message-----
From: Vivi, Rodrigo <rodrigo.vivi at intel.com> 
Sent: Wednesday, June 5, 2024 3:10 PM
To: Cavitt, Jonathan <jonathan.cavitt at intel.com>
Cc: intel-xe at lists.freedesktop.org; Gupta, saurabhg <saurabhg.gupta at intel.com>; Brost, Matthew <matthew.brost at intel.com>; Harrison, John C <john.c.harrison at intel.com>; Summers, Stuart <stuart.summers at intel.com>
Subject: Re: [PATCH] drm/xe/xe_gt_debugfs: Add synchronous gt reset debugfs
> 
> On Wed, Jun 05, 2024 at 08:08:28AM -0700, Jonathan Cavitt wrote:
> > We currently have debugfs support that allows the userspace to initiate
> > an asynchronous gt reset on command.  However, userspace may also wish
> > to wait for the completion of the gt reset before performing any
> > additional work.  To that end, add a version of the force_reset gt
> > debugfs function that operates synchronously.
> > 
> > Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1068
> 
> do we already have the igt changes that really closes this?

The IGT change that closes this issue has not yet landed.  It relies on
using the new debugfs, so if it landed first, we'd be attempting to call
a nonexistent debugfs function.
-Jonathan Cavitt

> 
> > Suggested-by: Matthew Brost <matthew.brost at intel.com>
> > Signed-off-by: Jonathan Cavitt <jonathan.cavitt at intel.com>
> > CC: John Harrison <john.c.harrison at intel.com>
> > CC: Stuart Summers <stuart.summers at intel.com>
> > ---
> >  drivers/gpu/drm/xe/xe_gt_debugfs.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/xe/xe_gt_debugfs.c b/drivers/gpu/drm/xe/xe_gt_debugfs.c
> > index 66f897a9b6ca9..5e7fd937917a1 100644
> > --- a/drivers/gpu/drm/xe/xe_gt_debugfs.c
> > +++ b/drivers/gpu/drm/xe/xe_gt_debugfs.c
> > @@ -116,6 +116,17 @@ static int force_reset(struct xe_gt *gt, struct drm_printer *p)
> >  	return 0;
> >  }
> >  
> > +static int force_reset_sync(struct xe_gt *gt, struct drm_printer *p)
> > +{
> > +	xe_pm_runtime_get(gt_to_xe(gt));
> > +	xe_gt_reset_async(gt);
> > +	xe_pm_runtime_put(gt_to_xe(gt));
> > +
> > +	flush_work(&gt->reset.worker);
> > +
> > +	return 0;
> > +}
> > +
> >  static int sa_info(struct xe_gt *gt, struct drm_printer *p)
> >  {
> >  	struct xe_tile *tile = gt_to_tile(gt);
> > @@ -261,6 +272,7 @@ static int vecs_default_lrc(struct xe_gt *gt, struct drm_printer *p)
> >  static const struct drm_info_list debugfs_list[] = {
> >  	{"hw_engines", .show = xe_gt_debugfs_simple_show, .data = hw_engines},
> >  	{"force_reset", .show = xe_gt_debugfs_simple_show, .data = force_reset},
> > +	{"force_reset_sync", .show = xe_gt_debugfs_simple_show, .data = force_reset_sync},
> >  	{"sa_info", .show = xe_gt_debugfs_simple_show, .data = sa_info},
> >  	{"topology", .show = xe_gt_debugfs_simple_show, .data = topology},
> >  	{"steering", .show = xe_gt_debugfs_simple_show, .data = steering},
> > -- 
> > 2.25.1
> > 
>