Re: [PATCH 2/5] drm/xe: Add ref counting for xe_file

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

On Mon, Jul 08, 2024 at 03:15:52PM -0700, Umesh Nerlige Ramappa wrote:
> On Mon, Jul 08, 2024 at 09:23:15PM +0000, Matthew Brost wrote:
> > On Mon, Jul 08, 2024 at 01:21:00PM -0700, Umesh Nerlige Ramappa wrote:
> > > Add ref counting for xe_file.
> > > 
> > 
> > Patch LGTM, but a nit I'd make this first patch in the series.
> 
> First patch was just a refactor. This one depends on xe_file_destroy()
> defined in the first patch though, so cannot reorder. I could squash it
> instead if that helps.
> 

Fine with it as is if that is easier. No need to squash.

Matt

> Umesh
> > 
> > > Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> > > ---
> > >  drivers/gpu/drm/xe/xe_device.c       |  7 +++++--
> > >  drivers/gpu/drm/xe/xe_device.h       | 12 ++++++++++++
> > >  drivers/gpu/drm/xe/xe_device_types.h |  3 +++
> > >  3 files changed, 20 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
> > > index babb697652d5..e6eacf1bcce0 100644
> > > --- a/drivers/gpu/drm/xe/xe_device.c
> > > +++ b/drivers/gpu/drm/xe/xe_device.c
> > > @@ -87,11 +87,14 @@ static int xe_file_open(struct drm_device *dev, struct drm_file *file)
> > >  	spin_unlock(&xe->clients.lock);
> > > 
> > >  	file->driver_priv = xef;
> > > +	kref_init(&xef->refcount);
> > > +
> > >  	return 0;
> > >  }
> > > 
> > > -static void xe_file_destroy(struct xe_file *xef)
> > 
> > Kernel doc as this is exported.
> > 
> > > +void xe_file_destroy(struct kref *ref)
> > >  {
> > > +	struct xe_file *xef = container_of(ref, struct xe_file, refcount);
> > >  	struct xe_device *xe = xef->xe;
> > >  	struct xe_vm *vm;
> > >  	unsigned long idx;
> > > @@ -130,7 +133,7 @@ static void xe_file_close(struct drm_device *dev, struct drm_file *file)
> > >  		xe_exec_queue_put(q);
> > >  	}
> > > 
> > > -	xe_file_destroy(xef);
> > > +	xe_file_put(xef);
> > >  }
> > > 
> > >  static const struct drm_ioctl_desc xe_ioctls[] = {
> > > diff --git a/drivers/gpu/drm/xe/xe_device.h b/drivers/gpu/drm/xe/xe_device.h
> > > index bb07f5669dbb..2a8b370b1fda 100644
> > > --- a/drivers/gpu/drm/xe/xe_device.h
> > > +++ b/drivers/gpu/drm/xe/xe_device.h
> > > @@ -169,5 +169,17 @@ static inline bool xe_device_wedged(struct xe_device *xe)
> > >  }
> > > 
> > >  void xe_device_declare_wedged(struct xe_device *xe);
> > > +void xe_file_destroy(struct kref *ref);
> > > +
> > 
> > I forget if this is a hard rule, but public static inlines likely should
> > have kernl doc too.
> > 
> > Matt
> > 
> > > +static inline struct xe_file *xe_file_get(struct xe_file *xef)
> > > +{
> > > +	kref_get(&xef->refcount);
> > > +	return xef;
> > > +}
> > > +
> > > +static inline void xe_file_put(struct xe_file *xef)
> > > +{
> > > +	kref_put(&xef->refcount, xe_file_destroy);
> > > +}
> > > 
> > >  #endif
> > > diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h
> > > index c37be471d11c..ec2b0fb6afe1 100644
> > > --- a/drivers/gpu/drm/xe/xe_device_types.h
> > > +++ b/drivers/gpu/drm/xe/xe_device_types.h
> > > @@ -566,6 +566,9 @@ struct xe_file {
> > > 
> > >  	/** @client: drm client */
> > >  	struct xe_drm_client *client;
> > > +
> > > +	/** @refcount: ref count of this xe file */
> > > +	struct kref refcount;
> > >  };
> > > 
> > >  #endif
> > > --
> > > 2.38.1
> > >