Re: [Pcihpd-discuss] [PATCH 26/34] PCI: add pci_try_set_mwi

[Randy Dunlap <randy.dunlap@oracle.com>]

On Wed, 11 Jul 2007 17:37:31 -0700 Greg KH wrote:

> On Wed, Jul 11, 2007 at 06:01:49PM -0600, Matthew Wilcox wrote:
> > On Wed, Jul 11, 2007 at 04:31:40PM -0700, Greg Kroah-Hartman wrote:
> > > As suggested by Andrew, add pci_try_set_mwi(), which does not require
> > > return-value checking.
> > 
> > Seems like a daft suggestion.  What's wrong with just removing the
> > __must_check from pci_set_mwi()?  Did it find any bugs?

(a) Alan suggested just dropping __must_check IIRC.
And David Brownell even sent a patch to do that (which Alan acked).

(b) not that I know of.

> > > --- a/drivers/scsi/lpfc/lpfc_init.c
> > > +++ b/drivers/scsi/lpfc/lpfc_init.c
> > > @@ -1578,10 +1578,7 @@ lpfc_pci_probe_one(struct pci_dev *pdev, const struct pci_device_id *pid)
> > >  	INIT_LIST_HEAD(&phba->fc_nodes);
> > >  
> > >  	pci_set_master(pdev);
> > > -	retval = pci_set_mwi(pdev);
> > > -	if (retval)
> > > -		dev_printk(KERN_WARNING, &pdev->dev,
> > > -			   "Warning: pci_set_mwi returned %d\n", retval);
> > > +	pci_try_set_mwi(pdev);
> > 
> > Why remove the warning?  Presumably people want to know if pci_set_mwi
> > failed.
> 
> Randy, this was your change, right?

Uh, I think that my thinking was like this:

pci_try_set_mwi() and pci_set_mwi() are both "try best effort"
functions.  Neither of them guarantees that pci_set_cacheline_size()
will succeed.  And in case of serious problems, pci_set_cacheline_size()
will print a (KERN_DEBUG) message.


Anyway, I don't mind restoring the former lpfc code if that is what
should be done.

---
~Randy
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