Re: [PATCH V9 8/9] cxl/port: Retry reading CDAT on failure

From: Ira Weiny <ira.weiny@intel.com>
To: Alison Schofield <alison.schofield@intel.com>
Cc: "Williams, Dan J" <dan.j.williams@intel.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	"Verma, Vishal L" <vishal.l.verma@intel.com>,
	"Jiang, Dave" <dave.jiang@intel.com>,
	Ben Widawsky <ben@bwidawsk.net>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-cxl@vger.kernel.org" <linux-cxl@vger.kernel.org>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>
Subject: Re: [PATCH V9 8/9] cxl/port: Retry reading CDAT on failure
Date: Tue, 31 May 2022 21:54:44 -0700	[thread overview]
Message-ID: <YpbxFL4hhZMT2eIW@iweiny-desk3> (raw)
In-Reply-To: <20220531170743.GA1457068@alison-desk>

On Tue, May 31, 2022 at 10:07:43AM -0700, Alison Schofield wrote:
> On Tue, May 31, 2022 at 08:26:31AM -0700, Ira Weiny wrote:
> > From: Ira Weiny <ira.weiny@intel.com>
> > 
> > The CDAT read may fail for a number of reasons but mainly it is possible
> > to get different parts of a valid state.  The checksum in the CDAT table
> > protects against this.
> > 
> > Now that the cdat data is validated issue a retries if the CDAT read
> > fails.  For now 5 retries are implemented.
> > 
> > Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> > 
> > ---
> 
> snip
> 
> > +
> > +void read_cdat_data(struct cxl_port *port)
> > +{
> > +	int retries = 5;
> > +	int rc;
> > +
> > +	while (retries--) {
> > +		rc = __read_cdat_data(port);
> > +		if (!rc)
> > +			break;
> > +		dev_err(&port->dev,
> > +			"CDAT data read error rc=%d (retries %d)\n",
> > +			rc, retries);
> > +	}
> 
> Perhaps dev_dbg() on retries and dev_err() only when retries are exhausted.

Yes thanks!
Ira

> 
> 
> >  }
> >  EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL);
> > -- 
> > 2.35.1
> > 