Re: [PATCH v3 6/8] cxl/region: Move ready-to-probe state check to a helper

[<dan.j.williams@intel.com>]

Jonathan Cameron wrote:
> On Fri, 11 Jul 2025 16:49:30 -0700
> Dan Williams <dan.j.williams@intel.com> wrote:
> 
> > Rather than unlocking the region rwsem in the middle of cxl_region_probe()
> > create a helper for determining when the region is ready-to-probe.
> I'd maybe mention the odd bit of 
> if (rc)
> 	return rc;
> 
> return 0;
> 
> Will go away shortly. Or maybe that is overkill for a commit message.
> 
> Anyhow, with that in mind LGTM
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> 
> 
> > 
> > Cc: Davidlohr Bueso <dave@stgolabs.net>
> > Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
> > Cc: Dave Jiang <dave.jiang@intel.com>
> > Cc: Alison Schofield <alison.schofield@intel.com>
> > Cc: Vishal Verma <vishal.l.verma@intel.com>
> > Cc: Ira Weiny <ira.weiny@intel.com>
> > Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> > Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> > ---
> >  drivers/cxl/core/region.c | 24 ++++++++++++++++++------
> >  1 file changed, 18 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> > index 3a77aec2c447..2a97fa9a394f 100644
> > --- a/drivers/cxl/core/region.c
> > +++ b/drivers/cxl/core/region.c
> > @@ -3572,9 +3572,8 @@ static void shutdown_notifiers(void *_cxlr)
> >  	unregister_mt_adistance_algorithm(&cxlr->adist_notifier);
> >  }
> >  
> > -static int cxl_region_probe(struct device *dev)
> > +static int cxl_region_can_probe(struct cxl_region *cxlr)
> >  {
> > -	struct cxl_region *cxlr = to_cxl_region(dev);
> >  	struct cxl_region_params *p = &cxlr->params;
> >  	int rc;
> >  
> > @@ -3597,15 +3596,28 @@ static int cxl_region_probe(struct device *dev)
> >  		goto out;
> >  	}
> >  
> > -	/*
> > -	 * From this point on any path that changes the region's state away from
> > -	 * CXL_CONFIG_COMMIT is also responsible for releasing the driver.
> > -	 */
> >  out:
> >  	up_read(&cxl_region_rwsem);
> >  
> >  	if (rc)
> >  		return rc;
> > +	return 0;
> 
> This is an odd bit of code now.  Why not just
> 
> 	return rc;
> 
> Ah. Patch 8 drops the if (rc) return rc bit.

It was an artifact of how it was developed. I am inclined to let it be
unless something else major comes up.