This series enables the ring-based dirty memory tracking for ARM64.
The feature has been available and enabled on x86 for a while. It
is beneficial when the number of dirty pages is small in a checkpointing
system or live migration scenario. More details can be found from
fb04a1eddb1a ("KVM: X86: Implement ring-based dirty memory tracking").
This series is applied to v6.1.rc3, plus commit c227590467cb ("KVM:
Check KVM_CAP_DIRTY_LOG_{RING, RING_ACQ_REL} prior to enabling them").
The commit is currently in Marc's 'fixes' branch, targeting v6.1.rc4/5.
v7: https://lore.kernel.org/kvmarm/20221031003621.164306-1-gs...@redhat.com/
v6: https://lore.kernel.org/kvmarm/20221011061447.131531-1-gs...@redhat.com/
v5: https://lore.kernel.org/all/20221005004154.83502-1-gs...@redhat.com/
v4: https://lore.kernel.org/kvmarm/20220927005439.21130-1-gs...@redhat.com/
v3: https://lore.kernel.org/r/20220922003214.276736-1-gs...@redhat.com
v2: https://lore.kernel.org/lkml/YyiV%2Fl7O23aw5aaO@xz-m1.local/T/
v1: https://lore.kernel.org/lkml/20220819005601.198436-1-gs...@redhat.com
Testing
===
(1) kvm/selftests/dirty_log_test
(2) Live migration by QEMU
Changelog
=
v8:
* Pick review-by and ack-by (Peter/Sean)
* Drop chunk of code to clear KVM_REQ_DIRTY_RING_SOFT_FULL
in kvm_dirty_ring_reset(). Add comments to say the event
will be cleared by the VCPU thread next time when it enters
the guest. All other changes related to kvm_dirty_ring_reset()
are dropped in PATCH[v8 1/7].
(Sean/Peter/Marc)
* Drop PATCH[v7 3/7] since it has been merged (Marc/Oliver)
* Document the order of DIRTY_RING_{ACQ_REL, WITH_BITMAP},
add check to ensure no memslots are created when
DIRTY_RING_WITH_BITMAP is enabled, and add weak function
kvm_arch_allow_write_without_running_vcpu() in PATCH[v8 3/7] (Oliver)
* Only keep ourself out of non-running-vcpu radar when vgic/its
tables are being saved in PATCH[v8 4/7] (Marc/Sean)
v7:
* Cut down #ifdef, avoid using 'container_of()', move the
dirty-ring check after KVM_REQ_VM_DEAD, add comments
for kvm_dirty_ring_check_request(), use tab character
for KVM event definitions in kvm_host.h in PATCH[v7 01](Sean)
* Add PATCH[v7 03] to recheck if the capability has
been advertised prior to enable RING/RING_ACEL_REL (Sean)
* Improve the description about capability RING_WITH_BITMAP,
rename kvm_dirty_ring_exclusive() to kvm_use_dirty_bitmap()
in PATCH[v7 04/09]
(Peter/Oliver/Sean)
* Add PATCH[v7 05/09] to improve no-running-vcpu report (Marc/Sean)
* Improve commit messages(Sean/Oliver)
v6:
* Add CONFIG_HAVE_KVM_DIRTY_RING_WITH_BITMAP, for arm64
to advertise KVM_CAP_DIRTY_RING_WITH_BITMAP in
PATCH[v6 3/8] (Oliver/Peter)
* Add helper kvm_dirty_ring_exclusive() to check if
traditional bitmap-based dirty log tracking is
exclusive to dirty-ring in PATCH[v6 3/8] (Peter)
* Enable KVM_CAP_DIRTY_RING_WITH_BITMAP in PATCH[v6 5/8] (Gavin)
v5:
* Drop empty stub kvm_dirty_ring_check_request() (Marc/Peter)
* Add PATCH[v5 3/7] to allow using bitmap, indicated by
KVM_CAP_DIRTY_LOG_RING_ALLOW_BITMAP(Marc/Peter)
v4:
* Commit log improvement (Marc)
* Add helper kvm_dirty_ring_check_request() (Marc)
* Drop ifdef for kvm_cpu_dirty_log_size()(Marc)
v3:
* Check KVM_REQ_RING_SOFT_RULL inside kvm_request_pending() (Peter)
* Move declaration of kvm_cpu_dirty_log_size() (test-robot)
v2:
* Introduce KVM_REQ_RING_SOFT_FULL (Marc)
* Changelog improvement (Marc)
* Fix dirty_log_test without knowing host page size (Drew)
Gavin Shan (7):
KVM: x86: Introduce KVM_REQ_DIRTY_RING_SOFT_FULL
KVM: Move declaration of kvm_cpu_dirty_log_size() to kvm_dirty_ring.h
KVM: Support dirty ring in conjunction with bitmap
KVM: arm64: Enable ring-based dirty memory tracking
KVM: selftests: Use host page size to map ring buffer in
dirty_log_test
KVM: selftests: Clear dirty ring states between two modes in
dirty_log_test
KVM: selftests: Automate choosing dirty ring size in dirty_log_test
Documentation/virt/kvm/api.rst | 35 ++---
arch/arm64/include/uapi/asm/kvm.h| 1 +
arch/arm64/kvm/Kconfig | 2 +
arch/arm64/kvm/arm.c | 3 ++
arch/arm64/kvm/mmu.c | 15 ++
arch/arm64/kvm/vgic/vgic-its.c | 3 ++
arch/arm64/kvm/vgic/vgic-mmio-v3.c | 7 +++
arch/x86/include/asm/kvm_host.h | 2 -
arch/x86/kvm/x86.c | 15
