openstack
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nova
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Merge "libvirt: Refactor handling of PCIe root ports"

This commit is contained in:
Zuul 2018-12-07 05:20:09 +00:00 committed by Gerrit Code Review
parent 61cd9ccc45 b65246ab4d
commit 152cdd6396
1 changed files with 40 additions and 8 deletions
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48
nova/virt/libvirt/driver.py
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@ -5120,6 +5120,45 @@ class LibvirtDriver(driver.ComputeDriver):
pcierootport = vconfig.LibvirtConfigGuestPCIeRootPortController()
guest.add_device(pcierootport)
def _guest_needs_pcie(self, guest, caps):
"""Check for prerequisites for adding PCIe root port
controllers
"""
# TODO(kchamart) In the third 'if' conditional below, for 'x86'
# arch, we're assuming: when 'os_mach_type' is 'None', you'll
# have "pc" machine type. That assumption, although it is
# correct for the "forseeable future", it will be invalid when
# libvirt / QEMU changes the default machine types.
#
# From libvirt 4.7.0 onwards (September 2018), it will ensure
# that *if* 'pc' is available, it will be used as the default --
# to not break existing applications. (Refer:
# https://libvirt.org/git/?p=libvirt.git;a=commit;h=26cfb1a3
# --"qemu: ensure default machine types don't change if QEMU
# changes").
#
# But even if libvirt (>=v4.7.0) handled the default case,
# relying on such assumptions is not robust. Instead we should
# get the default machine type for a given architecture reliably
# -- by Nova setting it explicitly (we already do it for Arm /
# AArch64 & s390x). A part of this bug is being tracked here:
# https://bugs.launchpad.net/nova/+bug/1780138).
# Add PCIe root port controllers for PCI Express machines
# but only if their amount is configured
if not CONF.libvirt.num_pcie_ports:
return False
if (caps.host.cpu.arch == fields.Architecture.AARCH64
and guest.os_mach_type.startswith('virt')):
return True
if (caps.host.cpu.arch == fields.Architecture.X86_64
and guest.os_mach_type is not None
and 'q35' in guest.os_mach_type):
return True
return False
def _guest_add_usb_host_keyboard(self, guest):
"""Add USB Host controller and keyboard for graphical console use.
@ -5248,14 +5287,7 @@ class LibvirtDriver(driver.ComputeDriver):
if virt_type in ('qemu', 'kvm'):
self._set_qemu_guest_agent(guest, flavor, instance, image_meta)
# Add PCIe root port controllers for PCI Express machines
# but only if their amount is configured
if (CONF.libvirt.num_pcie_ports and
((caps.host.cpu.arch == fields.Architecture.AARCH64 and
guest.os_mach_type.startswith('virt')) or
(caps.host.cpu.arch == fields.Architecture.X86_64 and
guest.os_mach_type is not None and
'q35' in guest.os_mach_type))):
if self._guest_needs_pcie(guest, caps):
self._guest_add_pcie_root_ports(guest)
self._guest_add_pci_devices(guest, instance)