From: Jack Thomson <[email protected]> This patch series adds ARM64 support for the KVM_PRE_FAULT_MEMORY feature, which was previously only available on x86 [1]. This allows us to reduce the number of stage-2 faults during execution. This is of benefit in post-copy migration scenarios, particularly in memory intensive applications, where we are experiencing high latencies due to the stage-2 faults.
Patch Overview: - The first patch adds support for the KVM_PRE_FAULT_MEMORY ioctl on arm64. - The second patch updates the pre_fault_memory_test to support arm64. - The last patch extends the pre_fault_memory_test to cover different vm memory backings. === Changes Since v2 [2] === - Update fault info synthesize value. Thanks Suzuki - Remove change to selftests for unaligned mmap allocations. Thanks Sean [1]: https://lore.kernel.org/kvm/[email protected] [2]: https://lore.kernel.org/linux-arm-kernel/[email protected] Jack Thomson (3): KVM: arm64: Add pre_fault_memory implementation KVM: selftests: Enable pre_fault_memory_test for arm64 KVM: selftests: Add option for different backing in pre-fault tests Documentation/virt/kvm/api.rst | 3 +- arch/arm64/kvm/Kconfig | 1 + arch/arm64/kvm/arm.c | 1 + arch/arm64/kvm/mmu.c | 73 +++++++++++- tools/testing/selftests/kvm/Makefile.kvm | 1 + .../selftests/kvm/pre_fault_memory_test.c | 110 ++++++++++++++---- 6 files changed, 159 insertions(+), 30 deletions(-) base-commit: 8a4821412cf2c1429fffa07c012dd150f2edf78c -- 2.43.0
