[PATCH v3 00/55] KVM: arm/arm64: Rework virtual GIC emulation

Andre Przywara andre.przywara at arm.com
Fri May 6 03:45:13 PDT 2016


Hi,

another week, another rework of the new-VGIC series.
Mostly minor changes this time, some moving and streamlining of patches
(move prototypes to the same patch as the definition etc.)
The most prominent change though is the rework of the GICv2 CPU
interface access functionality. It turns out that this was not properly
wired, so now we treat is very similar to the distributor registers
and declare the registers in our register structure.
Find a summary changelog below and more details in the respective patches.

As this new VGIC emulation will probably become the default very shortly,
please test it full steam on whatever setup you have access to.
Any reports are warmly welcome.

This series is still based on v4.6-rc5 as the previous version, though
a test rebase to -rc6 didn't trigger any issues.
A git tree containing this series can be found on linux-arm.org:

git://linux-arm.org/linux-ap.git	branch: vgic-new/v3
http://www.linux-arm.org/git?p=linux-ap.git;a=log;h=refs/heads/vgic-new/v3

Cheers,
Andre.

Changelog v2 .. v3:
- arch_timer: remove bogus validity check from kvm_vgic_unmap_phys_irq()
- arch_timer: simplify return in kvm_timer_vcpu_reset()
- move some code between patches to fix rebase artifacts
- add patch 12/55 to move some definitions into arm-vgic-v3.h
- replace inclusions of vgic/vgic.h with arm_vgic.h
- rename v3 redist register description variables to _rdbase_ and _sgibase_
- don't export VMCR accessor wrappers
- rework CPU i/f access from userland, moving code into vgic-mmio-v2.c
- make ich_vtr_el2 variable local

===========================
This series is a joint effort to re-implement KVM's GIC emulation.

While the current implementation is centered around providing
efficient MMIO emulation, the hot path for most guests is actually
the guest entry and exit, which currently is rather costly.
Also the existing emulation has a global distributor lock, which
quickly becomes a bottleneck once the number of VCPUs increases.
Additionally the emulation was originally designed for GICv2, adding
GICv3 ITS emulation support to this proved to be rather painful.
Last, but not least the existing code became less and less
maintainable, with many special cases handled explicitly.

The new implementation is build around a struct vgic_irq data
structure, which holds all information about a virtual interrupt.
Interruts which should be injected are held in a per-VCPU list, this
make the entry/exit path much more efficient. Also the new structure
allows to have more fine grained locking - per IRQ and per VCPU -
getting rid of the global distributor lock.
As a result of the new design ITS emulation fits in more nicely, the
respective code will be provided as a follow-up series.

This series implements the same feature set as the existing emulation,
as a goodie we now implement priorities correctly.
To allow an easy transition with good test coverage, but still maintain
stability, both implementations live side by side, selectable via a
Kconfig option. The default is the new implementation.
If this code proves to be reliable, we will later remove the current
implementation with an extra patch set.

Please have a look at the series, review it and give the code some
serious testing (and possibly debugging). All feedback is appreciated.

Cheers,
Andre.

Andre Przywara (29):
  KVM: arm/arm64: vgic: streamline vgic_update_irq_pending() interface
  KVM: arm/arm64: vgic: avoid map in kvm_vgic_inject_mapped_irq()
  KVM: arm/arm64: vgic: avoid map in kvm_vgic_map_is_active()
  KVM: arm/arm64: vgic: avoid map in kvm_vgic_unmap_phys_irq()
  KVM: arm/arm64: arch_timer: Remove irq_phys_map
  KVM: arm/arm64: vgic: Remove irq_phys_map from interface
  KVM: arm/arm64: pmu: abstract access to number of SPIs
  KVM: arm/arm64: move GICv2 emulation defines into arm-gic-v3.h
  KVM: arm/arm64: vgic-new: Add GICv2 MMIO handling framework
  KVM: arm/arm64: vgic-new: Add ENABLE registers handlers
  KVM: arm/arm64: vgic-new: Add PENDING registers handlers
  KVM: arm/arm64: vgic-new: Add ACTIVE registers handlers
  KVM: arm/arm64: vgic-new: Add PRIORITY registers handlers
  KVM: arm/arm64: vgic-new: Add CONFIG registers handlers
  KVM: arm/arm64: vgic-new: Add TARGET registers handlers
  KVM: arm/arm64: vgic-new: Add SGIR register handler
  KVM: arm/arm64: vgic-new: Add SGIPENDR register handlers
  KVM: arm/arm64: vgic-new: Add GICv3 MMIO handling framework
  KVM: arm/arm64: vgic-new: Add GICv3 CTLR, IIDR, TYPER handlers
  KVM: arm/arm64: vgic-new: Add GICv3 redistributor IIDR and TYPER handler
  KVM: arm/arm64: vgic-new: Add GICv3 IDREGS register handler
  KVM: arm/arm64: vgic-new: Add GICv3 IROUTER register handlers
  KVM: arm/arm64: vgic-new: Add GICv3 SGI system register trap handler
  KVM: arm/arm64: vgic-new: Add userland access to VGIC dist registers
  KVM: arm/arm64: vgic-new: Add GICH_VMCR accessors
  KVM: arm/arm64: vgic-new: Add userland GIC CPU interface access
  KVM: arm/arm64: vgic-new: Wire up irqfd injection
  KVM: arm/arm64: vgic-new: implement mapped IRQ handling
  KVM: arm/arm64: vgic-new: enable build

Christoffer Dall (9):
  KVM: arm/arm64: Remove the IRQ field from struct irq_phys_map
  KVM: arm/arm64: Get rid of vgic_cpu->nr_lr
  KVM: arm/arm64: Fix MMIO emulation data handling
  KVM: arm/arm64: Export mmio_read/write_bus
  KVM: arm/arm64: vgic-new: Add data structure definitions
  KVM: arm/arm64: vgic-new: Add acccessor to new struct vgic_irq instance
  KVM: arm/arm64: vgic-new: Implement virtual IRQ injection
  KVM: arm/arm64: vgic-new: Add IRQ sorting
  KVM: arm/arm64: vgic-new: Export register access interface

Eric Auger (12):
  KVM: arm/arm64: vgic-new: Implement kvm_vgic_vcpu_pending_irq
  KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM device ops registration
  KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_NR_IRQS
  KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_CTRL
  KVM: arm/arm64: vgic-new: vgic_kvm_device: implement kvm_vgic_addr
  KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_ADDR
  KVM: arm/arm64: vgic-new: vgic_kvm_device: access to VGIC registers
  KVM: arm/arm64: vgic-new: vgic_init: implement kvm_vgic_hyp_init
  KVM: arm/arm64: vgic-new: vgic_init: implement vgic_create
  KVM: arm/arm64: vgic-new: vgic_init: implement vgic_init
  KVM: arm/arm64: vgic-new: vgic_init: implement map_resources
  KVM: arm/arm64: vgic-new: Add vgic_v2/v3_enable

Marc Zyngier (5):
  KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework
  KVM: arm/arm64: vgic-new: Add GICv2 world switch backend
  KVM: arm/arm64: vgic-new: Add GICv3 world switch backend
  KVM: arm/arm64: vgic-new: Add MMIO handling framework
  KVM: arm/arm64: vgic-new: Add CTLR, TYPER and IIDR handlers

 arch/arm/include/asm/kvm_mmio.h     |   3 +
 arch/arm/kvm/Kconfig                |   7 +
 arch/arm/kvm/Makefile               |  11 +
 arch/arm/kvm/mmio.c                 |  24 +-
 arch/arm64/include/asm/kvm_mmio.h   |   3 +
 arch/arm64/kvm/Kconfig              |   7 +
 arch/arm64/kvm/Makefile             |  12 +
 include/kvm/arm_arch_timer.h        |   3 -
 include/kvm/arm_vgic.h              |  20 +-
 include/kvm/vgic/vgic.h             | 253 +++++++++++++++
 include/linux/irqchip/arm-gic-v3.h  |   6 +
 include/linux/irqchip/arm-gic.h     |   2 +
 virt/kvm/arm/arch_timer.c           |  42 ++-
 virt/kvm/arm/hyp/vgic-v2-sr.c       |  17 +-
 virt/kvm/arm/pmu.c                  |   2 +-
 virt/kvm/arm/vgic-v2.c              |   4 +-
 virt/kvm/arm/vgic-v3.c              |   8 +-
 virt/kvm/arm/vgic.c                 |  86 ++---
 virt/kvm/arm/vgic/vgic-init.c       | 446 ++++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic-irqfd.c      |  52 +++
 virt/kvm/arm/vgic/vgic-kvm-device.c | 452 ++++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic-mmio-v2.c    | 422 +++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic-mmio-v3.c    | 464 +++++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic-mmio.c       | 523 ++++++++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic-mmio.h       | 128 ++++++++
 virt/kvm/arm/vgic/vgic-v2.c         | 358 +++++++++++++++++++++
 virt/kvm/arm/vgic/vgic-v3.c         | 333 +++++++++++++++++++
 virt/kvm/arm/vgic/vgic.c            | 615 ++++++++++++++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic.h            | 121 +++++++
 29 files changed, 4309 insertions(+), 115 deletions(-)
 create mode 100644 include/kvm/vgic/vgic.h
 create mode 100644 virt/kvm/arm/vgic/vgic-init.c
 create mode 100644 virt/kvm/arm/vgic/vgic-irqfd.c
 create mode 100644 virt/kvm/arm/vgic/vgic-kvm-device.c
 create mode 100644 virt/kvm/arm/vgic/vgic-mmio-v2.c
 create mode 100644 virt/kvm/arm/vgic/vgic-mmio-v3.c
 create mode 100644 virt/kvm/arm/vgic/vgic-mmio.c
 create mode 100644 virt/kvm/arm/vgic/vgic-mmio.h
 create mode 100644 virt/kvm/arm/vgic/vgic-v2.c
 create mode 100644 virt/kvm/arm/vgic/vgic-v3.c
 create mode 100644 virt/kvm/arm/vgic/vgic.c
 create mode 100644 virt/kvm/arm/vgic/vgic.h

-- 
2.7.3



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