On Monday, September 01, 2008 11:50 PM, Roland Dreier wrote: >To: Alex Chiang >Cc: Zhao, Yu; Jesse Barnes; linux-pci@xxxxxxxxxxxxxxx; Randy Dunlap; Greg KH; >Grant Grundler; Matthew Wilcox; linux-kernel@xxxxxxxxxxxxxxx; >kvm@xxxxxxxxxxxxxxx; virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx; >xen-devel@xxxxxxxxxxxxxxxxxxx >Subject: Re: [PATCH 2/4 v2] PCI: support ARI capability > > > > +config PCI_ARI > > > + bool "PCI ARI support" > > > + depends on PCI > > > + default n > > > + help > > > + This enables PCI Alternative Routing-ID Interpretation. > > > > This Kconfig help text is a little weak. Why not include the text > > you've already written here: > > > > Support Alternative Routing-ID Interpretation (ARI), which > > increases the number of functions that can be supported by a PCIe > > endpoint. ARI is required by SR-IOV. > >I agree with this improvement to the help text. But a further question >is whether ARI even merits its own user-visible config option. Is it >worth having yet another choice for users? When would someone want ARI >but not SR-IOV? ARI is an independent PCI Express extended capability. Multi-function devices supporting this capability may use it to track dependency between different functions and assign function group numbers to these functions. Another reason to keep this separated with SR-IOV is that after ARI is enabled, PCI Express Endpoint may have non-zero slot number (device number), which is different from traditional PCI Express Endpoint. Thanks. > > - R. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html