From mboxrd@z Thu Jan 1 00:00:00 1970 From: peng.hao2@zte.com.cn (Peng Hao) Date: Wed, 14 Mar 2018 05:03:13 +0800 Subject: [PATCH] KVM: arm/arm64: replacing per-VM's per-CPU variable Message-ID: <1520974993-40423-1-git-send-email-peng.hao2@zte.com.cn> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Using a global per-CPU variable instead of per-VM's per-CPU variable. Signed-off-by: Peng Hao --- arch/arm/include/asm/kvm_host.h | 3 --- arch/arm64/include/asm/kvm_host.h | 3 --- virt/kvm/arm/arm.c | 26 ++++++-------------------- 3 files changed, 6 insertions(+), 26 deletions(-) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 248b930..4224f3b 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -59,9 +59,6 @@ struct kvm_arch { /* VTTBR value associated with below pgd and vmid */ u64 vttbr; - /* The last vcpu id that ran on each physical CPU */ - int __percpu *last_vcpu_ran; - /* * Anything that is not used directly from assembly code goes * here. diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 596f8e4..5035a08 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -67,9 +67,6 @@ struct kvm_arch { /* VTTBR value associated with above pgd and vmid */ u64 vttbr; - /* The last vcpu id that ran on each physical CPU */ - int __percpu *last_vcpu_ran; - /* The maximum number of vCPUs depends on the used GIC model */ int max_vcpus; diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c index 86941f6..a67ffb0 100644 --- a/virt/kvm/arm/arm.c +++ b/virt/kvm/arm/arm.c @@ -59,6 +59,8 @@ /* Per-CPU variable containing the currently running vcpu. */ static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu); +static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_last_ran_vcpu); + /* The VMID used in the VTTBR */ static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1); static u32 kvm_next_vmid; @@ -115,18 +117,11 @@ void kvm_arch_check_processor_compat(void *rtn) */ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { - int ret, cpu; + int ret; if (type) return -EINVAL; - kvm->arch.last_vcpu_ran = alloc_percpu(typeof(*kvm->arch.last_vcpu_ran)); - if (!kvm->arch.last_vcpu_ran) - return -ENOMEM; - - for_each_possible_cpu(cpu) - *per_cpu_ptr(kvm->arch.last_vcpu_ran, cpu) = -1; - ret = kvm_alloc_stage2_pgd(kvm); if (ret) goto out_fail_alloc; @@ -147,9 +142,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) return ret; out_free_stage2_pgd: kvm_free_stage2_pgd(kvm); -out_fail_alloc: - free_percpu(kvm->arch.last_vcpu_ran); - kvm->arch.last_vcpu_ran = NULL; +out_fail_alloc: return ret; } @@ -179,9 +172,6 @@ void kvm_arch_destroy_vm(struct kvm *kvm) kvm_vgic_destroy(kvm); - free_percpu(kvm->arch.last_vcpu_ran); - kvm->arch.last_vcpu_ran = NULL; - for (i = 0; i < KVM_MAX_VCPUS; ++i) { if (kvm->vcpus[i]) { kvm_arch_vcpu_free(kvm->vcpus[i]); @@ -343,17 +333,13 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { - int *last_ran; - - last_ran = this_cpu_ptr(vcpu->kvm->arch.last_vcpu_ran); - /* * We might get preempted before the vCPU actually runs, but * over-invalidation doesn't affect correctness. */ - if (*last_ran != vcpu->vcpu_id) { + if (per_cpu(kvm_last_ran_vcpu, cpu) != vcpu) { kvm_call_hyp(__kvm_tlb_flush_local_vmid, vcpu); - *last_ran = vcpu->vcpu_id; + per_cpu(kvm_last_ran_vcpu, cpu) = vcpu; } vcpu->cpu = cpu; -- 1.8.3.1