Drop kvm_arch_sched_in() and instead add and use kvm_vcpu.scheduled_out to communicate to kvm_arch_vcpu_load() that the vCPU is being scheduling back in. While fiddling with an idea for optimizing state management on AMD CPUs, I wanted to skip re-saving certain host state when a vCPU is scheduled back in, as the state (theoretically) shouldn't change for the task while it's scheduled out. Actually doing that was annoying and unnecessarily brittle due to having a separate API for the kvm_sched_in() case (the state save needed to be in kvm_arch_vcpu_load() for the common path). The other motivation for this is to avoid yet another arch hook, and more arbitrary ordering, if there's a future need to hook kvm_sched_out() (we've come close on the x86 side several times). E.g. kvm_arch_vcpu_put() can simply check kvm_vcpu.scheduled_out if it needs to something specific for the vCPU being scheduled out. v2: - Add scheduled_out flag instead of passing a bool to kvm_arch_vcpu_load(). [Oliver] - Tack on patches to clean up x86's setting of l1tf_flush_l1d in kvm_arch_sched_load() (the code looked slightly less weird when the flag was being set by kvm_arch_sched_in()). v1: https://lore.kernel.org/all/20240430193157.419425-1-seanjc@xxxxxxxxxx Sean Christopherson (6): KVM: Add a flag to track if a loaded vCPU is scheduled out KVM: VMX: Move PLE grow/shrink helpers above vmx_vcpu_load() KVM: x86: Fold kvm_arch_sched_in() into kvm_arch_vcpu_load() KVM: Delete the now unused kvm_arch_sched_in() KVM: x86: Unconditionally set l1tf_flush_l1d during vCPU load KVM: x86: Drop now-superflous setting of l1tf_flush_l1d in vcpu_run() arch/arm64/include/asm/kvm_host.h | 1 - arch/loongarch/include/asm/kvm_host.h | 1 - arch/mips/include/asm/kvm_host.h | 1 - arch/powerpc/include/asm/kvm_host.h | 1 - arch/riscv/include/asm/kvm_host.h | 1 - arch/s390/include/asm/kvm_host.h | 1 - arch/x86/include/asm/kvm-x86-ops.h | 1 - arch/x86/include/asm/kvm_host.h | 2 - arch/x86/kvm/pmu.c | 6 +- arch/x86/kvm/svm/svm.c | 11 +--- arch/x86/kvm/vmx/main.c | 2 - arch/x86/kvm/vmx/vmx.c | 80 +++++++++++++-------------- arch/x86/kvm/vmx/x86_ops.h | 1 - arch/x86/kvm/x86.c | 22 +++----- include/linux/kvm_host.h | 3 +- virt/kvm/kvm_main.c | 5 +- 16 files changed, 59 insertions(+), 80 deletions(-) base-commit: 4aad0b1893a141f114ba40ed509066f3c9bc24b0 -- 2.45.0.215.g3402c0e53f-goog
