Looking up devices on the port I/O bus is time consuming during the
boot at there is an O(lg n) tree lookup and the overhead from taking a
lock on the bus contents.
Avoid this by adding a fast path uses the hardcoded port address and
size and directs PCI config requests directly to the device.
Command line:
target/release/cloud-hypervisor --kernel ~/src/linux/vmlinux --cmdline "root=/dev/vda1 console=ttyS0" --serial tty --console off --disk path=~/workloads/focal-server-cloudimg-amd64-custom-20210609-0.raw --api-socket /tmp/api
PIO exit: 17913
PCI fast path: 17871
Percentage on fast path: 99.8%
perf before:
marvin:~/src/cloud-hypervisor (main *)$ perf report -g | grep resolve
6.20% 6.20% vcpu0 cloud-hypervisor [.] vm_device:🚌:Bus::resolve
perf after:
marvin:~/src/cloud-hypervisor (2021-09-17-ioapic-fast-path *)$ perf report -g | grep resolve
0.08% 0.08% vcpu0 cloud-hypervisor [.] vm_device:🚌:Bus::resolve
The compromise required to implement this fast path is bringing the
creation of the PciConfigIo device into the DeviceManager::new() so that
it can be used in the VmmOps struct which is created before
DeviceManager::create_devices() is called.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Taking advantage of the refactored VFIO code implement a new
VfioUserPciDevice that wraps the client for vfio-user and exposes the
BusDevice and PciDevice into the VMM.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Now all crates use edition = "2018" then the majority of the "extern
crate" statements can be removed. Only those for importing macros need
to remain.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
warning: name `IORegion` contains a capitalized acronym
--> pci/src/configuration.rs:320:5
|
320 | IORegion = 0x01,
| ^^^^^^^^ help: consider making the acronym lowercase, except the initial letter (notice the capitalization): `IoRegion`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#upper_case_acronyms
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This removes the dependency of the pci crate on the devices crate which
now only contains the device implementations themselves.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Start moving the vmm, arch and pci crates to being hypervisor agnostic
by using the hypervisor trait and abstractions. This is not a complete
switch and there are still some remaining KVM dependencies.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
There is a much stronger PCI dependency from vfio_pci.rs than a VFIO one
from pci/src/vfio.rs. It seems more natural to have the PCI specific
VFIO implementation in the PCI crate rather than the other way around.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
In order to restore devices relying on MSI-X, the MsixConfig structure
must be restored with the correct values. Additionally, the KVM routes
must be restored so that interrupts can be delivered through KVM the way
they were configured before the snapshot was taken.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Both InterruptDelivery and InterruptParameters can be removed from the
pci crate as they are not used anymore.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that KVM specific interrupts are handled through InterruptManager
trait implementation, the pci crate does not need to rely on kvm_ioctls
and kvm_bindings crates.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Based on all the previous changes, we can at this point replace the
entire interrupt management with the implementation of InterruptManager
and InterruptSourceGroup traits.
By using KvmInterruptManager from the DeviceManager, we can provide both
VirtioPciDevice and VfioPciDevice a way to pick the kind of
InterruptSourceGroup they want to create. Because they choose the type
of interrupt to be MSI/MSI-X, they will be given a MsiInterruptGroup.
Both MsixConfig and MsiConfig are responsible for the update of the GSI
routes, which is why, by passing the MsiInterruptGroup to them, they can
still perform the GSI route management without knowing implementation
details. That's where the InterruptSourceGroup is powerful, as it
provides a generic way to manage interrupt, no matter the type of
interrupt and no matter which hypervisor might be in use.
Once the full replacement has been achieved, both SystemAllocator and
KVM specific dependencies can be removed.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The same way we have MsixConfig in charge of managing whatever relates
to MSI-X vectors, we need a MsiConfig structure to manage MSI vectors.
The MsiCap structure is still needed as a low level API, but it is now
part of the MsiConfig which oversees anything related to MSI.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that MsixConfig has access to both KVM VmFd and the list of GSI
routes, the update of the KVM GSI routes can be directly done from
MsixConfig instead of specifically from the vfio-pci implementation.
By moving the KVM GSI routes update at the MsixConfig level, both
vfio-pci and virtio-pci (or any other emulated PCI device) can benefit
from it, without having to implement it on their own.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to anticipate the need for both msi.rs and msix.rs to rely on
some KVM utils and InterruptRoute structure to handle the update of the
KVM GSI routes, this commit adds these utilities directly to the pci
crate. So far, these were exclusively used by the vfio crate, which is
why there were located there.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Based on the value being written to the BAR, the implementation can
now detect if the BAR is being moved to another address. If that is the
case, it invokes move_bar() function from the DeviceRelocation trait.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This new trait will allow the VMM to implement the mechanism following a
BAR modification regarding its location in the guest address space.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Refactor the PCI datastructures to move the device ownership to a PciBus
struct. This PciBus struct can then be used by both a PciConfigIo and
PciConfigMmio in order to expose the configuration space via both IO
port and also via MMIO for PCI MMCONFIG.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
In order to support use cases that require MSI, the pci crate is
being expanded with the description of an MSI PCI capability
structure through the new MsiCap Rust structure.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit enhances the current msi-x code hosted in the pci crate
in order to be reused by the vfio crate. Specifically, it creates
several useful methods for the MsixCap structure that can simplify
the caller's code.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
PciConfigIo is a legacy pci bus dispatcher, which manages all pci
devices including a pci root bridge. However, it is unnecessary to
design a complex hierarchy which redirects every access by PciRoot.
Since pci root bridge is also a pci device instance, and only contains
easy config space read/write, and PciConfigIo actually acts as a pci bus
to dispatch resource based resolving when VMExit, we re-arrange to make
the pci hierarchy clean.
Signed-off-by: Jing Liu <jing2.liu@linux.intel.com>
In order to factorize the complexity brought by closures, this commit
merges IrqClosure and MsixClosure into a generic InterruptDelivery one.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to allow virtio-pci devices to use MSI-X messages instead
of legacy pin based interrupts, this patch implements the MSI-X
support for cloud-hypervisor. The VMM code and virtio-pci bits have
been modified based on the "msix" module previously added to the pci
crate.
Fixes#12
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Because we cannot always assume the irq fd will be the way to send
an IRQ to the guest, this means we cannot make the assumption that
every virtio device implementation should expect an EventFd to
trigger an IRQ.
This commit organizes the code related to virtio devices so that it
now expects a Rust closure instead of a known EventFd. This lets the
caller decide what should be done whenever a device needs to trigger
an interrupt to the guest.
The closure will allow for other type of interrupt mechanism such as
MSI to be implemented. From the device perspective, it could be a
pin based interrupt or an MSI, it does not matter since the device
will simply call into the provided callback, passing the appropriate
Queue as a reference. This design keeps the device model generic.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Add the BSD and Apache license.
Make all crosvm references point to the BSD license.
Add the right copyrights and identifier to our VMM code.
Add Intel copyright to the vm-virtio and pci crates.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This crate is based on the crosvm devices/src/pci implementation from 107edb3e
We introduced a few changes:
- This one is a standalone crate. The device crate does not carry any
PCI specific bits.
- Simplified PCI root configuration. We only carry a pointer to a
PciConfiguration, not a wrapper around it.
- Simplified BAR allocation API. All BARs from the PciDevice instance
must be generated at once through the PciDevice.allocate_bars()
method.
- The PCI BARs are added to the MMIO bus from the PciRoot add_device()
method.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
