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authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-19 10:38:36 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-19 10:38:36 -0700
commite61cf2e3a5b452cfefcb145021f5a8ea88735cc1 (patch)
treebbabaf0d4753d6880ecbaddd8daa0164d49c1c61 /arch/x86/kernel/kvm.c
parent1009aa1205c2c5e9101437dcadfa195708d863bf (diff)
parent28a1f3ac1d0c8558ee4453d9634dad891a6e922e (diff)
downloadlwn-e61cf2e3a5b452cfefcb145021f5a8ea88735cc1.tar.gz
lwn-e61cf2e3a5b452cfefcb145021f5a8ea88735cc1.zip
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull first set of KVM updates from Paolo Bonzini: "PPC: - minor code cleanups x86: - PCID emulation and CR3 caching for shadow page tables - nested VMX live migration - nested VMCS shadowing - optimized IPI hypercall - some optimizations ARM will come next week" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (85 commits) kvm: x86: Set highest physical address bits in non-present/reserved SPTEs KVM/x86: Use CC_SET()/CC_OUT in arch/x86/kvm/vmx.c KVM: X86: Implement PV IPIs in linux guest KVM: X86: Add kvm hypervisor init time platform setup callback KVM: X86: Implement "send IPI" hypercall KVM/x86: Move X86_CR4_OSXSAVE check into kvm_valid_sregs() KVM: x86: Skip pae_root shadow allocation if tdp enabled KVM/MMU: Combine flushing remote tlb in mmu_set_spte() KVM: vmx: skip VMWRITE of HOST_{FS,GS}_BASE when possible KVM: vmx: skip VMWRITE of HOST_{FS,GS}_SEL when possible KVM: vmx: always initialize HOST_{FS,GS}_BASE to zero during setup KVM: vmx: move struct host_state usage to struct loaded_vmcs KVM: vmx: compute need to reload FS/GS/LDT on demand KVM: nVMX: remove a misleading comment regarding vmcs02 fields KVM: vmx: rename __vmx_load_host_state() and vmx_save_host_state() KVM: vmx: add dedicated utility to access guest's kernel_gs_base KVM: vmx: track host_state.loaded using a loaded_vmcs pointer KVM: vmx: refactor segmentation code in vmx_save_host_state() kvm: nVMX: Fix fault priority for VMX operations kvm: nVMX: Fix fault vector for VMX operation at CPL > 0 ...
Diffstat (limited to 'arch/x86/kernel/kvm.c')
-rw-r--r--arch/x86/kernel/kvm.c112
1 files changed, 111 insertions, 1 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 09aaabb2bbf1..0f471bd93417 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -444,6 +444,98 @@ static void __init sev_map_percpu_data(void)
}
#ifdef CONFIG_SMP
+#define KVM_IPI_CLUSTER_SIZE (2 * BITS_PER_LONG)
+
+static void __send_ipi_mask(const struct cpumask *mask, int vector)
+{
+ unsigned long flags;
+ int cpu, apic_id, icr;
+ int min = 0, max = 0;
+#ifdef CONFIG_X86_64
+ __uint128_t ipi_bitmap = 0;
+#else
+ u64 ipi_bitmap = 0;
+#endif
+
+ if (cpumask_empty(mask))
+ return;
+
+ local_irq_save(flags);
+
+ switch (vector) {
+ default:
+ icr = APIC_DM_FIXED | vector;
+ break;
+ case NMI_VECTOR:
+ icr = APIC_DM_NMI;
+ break;
+ }
+
+ for_each_cpu(cpu, mask) {
+ apic_id = per_cpu(x86_cpu_to_apicid, cpu);
+ if (!ipi_bitmap) {
+ min = max = apic_id;
+ } else if (apic_id < min && max - apic_id < KVM_IPI_CLUSTER_SIZE) {
+ ipi_bitmap <<= min - apic_id;
+ min = apic_id;
+ } else if (apic_id < min + KVM_IPI_CLUSTER_SIZE) {
+ max = apic_id < max ? max : apic_id;
+ } else {
+ kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap,
+ (unsigned long)(ipi_bitmap >> BITS_PER_LONG), min, icr);
+ min = max = apic_id;
+ ipi_bitmap = 0;
+ }
+ __set_bit(apic_id - min, (unsigned long *)&ipi_bitmap);
+ }
+
+ if (ipi_bitmap) {
+ kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap,
+ (unsigned long)(ipi_bitmap >> BITS_PER_LONG), min, icr);
+ }
+
+ local_irq_restore(flags);
+}
+
+static void kvm_send_ipi_mask(const struct cpumask *mask, int vector)
+{
+ __send_ipi_mask(mask, vector);
+}
+
+static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int vector)
+{
+ unsigned int this_cpu = smp_processor_id();
+ struct cpumask new_mask;
+ const struct cpumask *local_mask;
+
+ cpumask_copy(&new_mask, mask);
+ cpumask_clear_cpu(this_cpu, &new_mask);
+ local_mask = &new_mask;
+ __send_ipi_mask(local_mask, vector);
+}
+
+static void kvm_send_ipi_allbutself(int vector)
+{
+ kvm_send_ipi_mask_allbutself(cpu_online_mask, vector);
+}
+
+static void kvm_send_ipi_all(int vector)
+{
+ __send_ipi_mask(cpu_online_mask, vector);
+}
+
+/*
+ * Set the IPI entry points
+ */
+static void kvm_setup_pv_ipi(void)
+{
+ apic->send_IPI_mask = kvm_send_ipi_mask;
+ apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
+ apic->send_IPI_allbutself = kvm_send_ipi_allbutself;
+ apic->send_IPI_all = kvm_send_ipi_all;
+ pr_info("KVM setup pv IPIs\n");
+}
+
static void __init kvm_smp_prepare_cpus(unsigned int max_cpus)
{
native_smp_prepare_cpus(max_cpus);
@@ -611,13 +703,27 @@ static uint32_t __init kvm_detect(void)
return kvm_cpuid_base();
}
+static void __init kvm_apic_init(void)
+{
+#if defined(CONFIG_SMP)
+ if (kvm_para_has_feature(KVM_FEATURE_PV_SEND_IPI))
+ kvm_setup_pv_ipi();
+#endif
+}
+
+static void __init kvm_init_platform(void)
+{
+ kvmclock_init();
+ x86_platform.apic_post_init = kvm_apic_init;
+}
+
const __initconst struct hypervisor_x86 x86_hyper_kvm = {
.name = "KVM",
.detect = kvm_detect,
.type = X86_HYPER_KVM,
- .init.init_platform = kvmclock_init,
.init.guest_late_init = kvm_guest_init,
.init.x2apic_available = kvm_para_available,
+ .init.init_platform = kvm_init_platform,
};
static __init int activate_jump_labels(void)
@@ -736,6 +842,10 @@ void __init kvm_spinlock_init(void)
if (kvm_para_has_hint(KVM_HINTS_REALTIME))
return;
+ /* Don't use the pvqspinlock code if there is only 1 vCPU. */
+ if (num_possible_cpus() == 1)
+ return;
+
__pv_init_lock_hash();
pv_lock_ops.queued_spin_lock_slowpath = __pv_queued_spin_lock_slowpath;
pv_lock_ops.queued_spin_unlock = PV_CALLEE_SAVE(__pv_queued_spin_unlock);