BSDCan2015 - ZI

BSDCan 2015
The Technical BSD Conference

Ryan Stone
Day Talks #2 - 13 June - 2015-06-13
Room DMS 1140
Start time 10:00
Duration 01:00
ID 560
Event type Lecture
Track System Administration
Language used for presentation English


Hardware-assisted virtualization of PCI devices

PCI Single Root I/O Virtualization (SR-IOV) is an optional part of the PCIe standard that provides hardware acceleration for the virtualization of PCIe devices. When SR-IOV is in use, a function in a PCI device (known as a Physical Function, or PF) will present multiple Virtual PCI Functions (VF) on the PCI bus. These VFs are fully independent PCI devices that can use the functionality of the PF without the overhead of synchronizing with the driver for the PF or other VFs. SR-IOV allows for great improvements in network performance in virtualized environments compared to traditional software-only network virtualization.

SR-IOV is an important virtualization technology supported in a number of hypervisors. Although FreeBSD has long had support for acting as a guest OS in an SR-IOV environment, to date it has not been possible to use SR-IOV in combination with native virtualization technologies like vimage jails or bhyve.

This talk will cover the new SR-IOV infrastructure added to FreeBSD PCI subsystem, which allows the use of FreeBSD as an SR-IOV host. Discussion will focus on the use of SR-IOV by system administrators, with the balance of the talk devoted to the kernel API provided to PF driver maintainers.