diff options
| author | Lei Chen <lei.chen@smartx.com> | 2025-08-19 23:20:26 +0800 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2025-11-17 07:50:24 -0800 |
| commit | 446fcce2a52b533c543dabba26777813c347577c (patch) | |
| tree | c76eb544cf42a1471ae8f98e8d780ca1251530bb | |
| parent | 43ddbf16edf5c1790684b32d5eb920a1b0eea285 (diff) | |
Revert "x86: kvm: rate-limit global clock updates"
This reverts commit 7e44e4495a398eb553ce561f29f9148f40a3448f.
Commit 7e44e4495a39 ("x86: kvm: rate-limit global clock updates")
intends to use a kvmclock_update_work to sync ntp corretion
across all vcpus kvmclock, which is based on commit 0061d53daf26f
("KVM: x86: limit difference between kvmclock updates")
Since kvmclock has been switched to mono raw, this commit can be
reverted.
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Link: https://patch.msgid.link/20250819152027.1687487-3-lei.chen@smartx.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 29 |
2 files changed, 4 insertions, 26 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index adc8ea9d391b..692ec922945f 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1456,7 +1456,6 @@ struct kvm_arch { bool use_master_clock; u64 master_kernel_ns; u64 master_cycle_now; - struct delayed_work kvmclock_update_work; #ifdef CONFIG_KVM_HYPERV struct kvm_hv hyperv; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6c16067046bd..33fcd79e33da 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3523,22 +3523,14 @@ uint64_t kvm_get_wall_clock_epoch(struct kvm *kvm) * the others. * * So in those cases, request a kvmclock update for all vcpus. - * We need to rate-limit these requests though, as they can - * considerably slow guests that have a large number of vcpus. - * The time for a remote vcpu to update its kvmclock is bound - * by the delay we use to rate-limit the updates. + * The worst case for a remote vcpu to update its kvmclock + * is then bounded by maximum nohz sleep latency. */ - -#define KVMCLOCK_UPDATE_DELAY msecs_to_jiffies(100) - -static void kvmclock_update_fn(struct work_struct *work) +static void kvm_gen_kvmclock_update(struct kvm_vcpu *v) { unsigned long i; - struct delayed_work *dwork = to_delayed_work(work); - struct kvm_arch *ka = container_of(dwork, struct kvm_arch, - kvmclock_update_work); - struct kvm *kvm = container_of(ka, struct kvm, arch); struct kvm_vcpu *vcpu; + struct kvm *kvm = v->kvm; kvm_for_each_vcpu(i, vcpu, kvm) { kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); @@ -3546,15 +3538,6 @@ static void kvmclock_update_fn(struct work_struct *work) } } -static void kvm_gen_kvmclock_update(struct kvm_vcpu *v) -{ - struct kvm *kvm = v->kvm; - - kvm_make_request(KVM_REQ_CLOCK_UPDATE, v); - schedule_delayed_work(&kvm->arch.kvmclock_update_work, - KVMCLOCK_UPDATE_DELAY); -} - /* These helpers are safe iff @msr is known to be an MCx bank MSR. */ static bool is_mci_control_msr(u32 msr) { @@ -13163,8 +13146,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) kvm->arch.hv_root_tdp = INVALID_PAGE; #endif - INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn); - kvm_apicv_init(kvm); kvm_hv_init_vm(kvm); kvm_xen_init_vm(kvm); @@ -13271,8 +13252,6 @@ void kvm_arch_pre_destroy_vm(struct kvm *kvm) * is unsafe, i.e. will lead to use-after-free. The PIT also needs to * be stopped before IRQ routing is freed. */ - cancel_delayed_work_sync(&kvm->arch.kvmclock_update_work); - #ifdef CONFIG_KVM_IOAPIC kvm_free_pit(kvm); #endif |