On Wed, Jun 11, 2014 at 06:27:35PM +0000, Carew, Alan wrote: > > -----Original Message----- > > From: Neil Horman [mailto:nhorman at tuxdriver.com] > > Sent: Sunday, June 08, 2014 4:37 PM > > To: Stephen Hemminger > > Cc: Carew, Alan; dev at dpdk.org > > Subject: Re: [dpdk-dev] [PATCH v2 09/10] igbuio: show irq mode in sysfs > > > > On Fri, Jun 06, 2014 at 04:50:37PM -0700, Stephen Hemminger wrote: > > > Since irq mode is determined dynamically on a per-device > > > basis, and virtio needs to know if using intx or msi-x, > > > make it a sysfs attribute. > > > > > > --- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > > > +++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > > > @@ -43,6 +43,10 @@ > > > IGBUIO_MSIX_INTR_MODE > > > }; > > > > > > +static const char *igbuio_intr_modes[] = { > > > + "legacy", "msi", "msix" > > > +}; > > > + > > > /** > > > * A structure describing the private information for a uio device. > > > */ > > > @@ -128,8 +132,20 @@ > > > } > > > > > > static DEVICE_ATTR(max_vfs, S_IRUGO | S_IWUSR, show_max_vfs, > > store_max_vfs); > > > + > > > +static ssize_t irq_mode_show(struct device *dev, > > > + struct device_attribute *attr, char *buf) > > > +{ > > > + struct uio_info *info = pci_get_drvdata(to_pci_dev(dev)); > > > + struct rte_uio_pci_dev *udev = igbuio_get_uio_pci_dev(info); > > > + > > > + return sprintf(buf, "%s\n", igbuio_intr_modes[udev->mode]); > > > +} > > > +static DEVICE_ATTR(irq_mode, S_IRUGO, irq_mode_show, NULL); > > > + > > > static struct attribute *dev_attrs[] = { > > > &dev_attr_max_vfs.attr, > > > + &dev_attr_irq_mode.attr, > > > NULL, > > > }; > > > > > > > > > > > Do you really need this attribute? The pci bus sysfs tree already exports > > irq > > mode information for each device allocated already in > > /sys/bus/pci/device/msi_irqs<irq_number> > > > > Neil > > Hi Neil, > > After some digging around, I now realise what you mean, it is a good > suggestion. thanks.
> /sys/bus/pci/devices/<D:B:D.F>/msi_irqs/<IRQ>/mode, where "msi_irqs" > directory only exists for msi/msix and not for int-x. Also the "mode" file > contains string of configured interrupt mode. Yes, thats correct (although the file layout is slightly different in later kernels, as the mode is contained in a file that is named after the irq vector). For int-x interrupts you can query the /sys/bus/pci/devices/<D:B:D.F/irq file. Best Neil > > Thanks, > Alan >
