diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index fd248a318211a189163f2c42ba911a44284ea0bc..a7225746ed963c5479d9e4a6cca814f8bea7dc76 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1737,6 +1737,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page fault handling. + no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting. + steal time is computed, but won't influence scheduler + behaviour + nolapic [X86-32,APIC] Do not enable or use the local APIC. nolapic_timer [X86-32,APIC] Do not use the local APIC timer. diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index c484ba8e05eafd110fabeca15123709f0531b005..734c3767cfac96075b52a39a641d4430a4fb4102 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -192,6 +192,7 @@ void __init kvm_guest_init(void); void kvm_async_pf_task_wait(u32 token); void kvm_async_pf_task_wake(u32 token); u32 kvm_read_and_reset_pf_reason(void); +extern void kvm_disable_steal_time(void); #else #define kvm_guest_init() do { } while (0) #define kvm_async_pf_task_wait(T) do {} while(0) @@ -200,6 +201,11 @@ static inline u32 kvm_read_and_reset_pf_reason(void) { return 0; } + +static inline void kvm_disable_steal_time(void) +{ + return; +} #endif #endif /* __KERNEL__ */ diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 33c07b0b122eda52fae6dcb25879c639158429bc..a9c2116001d692f08b4d756cc90e7e5cd97ff3e5 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -51,6 +51,15 @@ static int parse_no_kvmapf(char *arg) early_param("no-kvmapf", parse_no_kvmapf); +static int steal_acc = 1; +static int parse_no_stealacc(char *arg) +{ + steal_acc = 0; + return 0; +} + +early_param("no-steal-acc", parse_no_stealacc); + struct kvm_para_state { u8 mmu_queue[MMU_QUEUE_SIZE]; int mmu_queue_len; @@ -58,6 +67,8 @@ struct kvm_para_state { static DEFINE_PER_CPU(struct kvm_para_state, para_state); static DEFINE_PER_CPU(struct kvm_vcpu_pv_apf_data, apf_reason) __aligned(64); +static DEFINE_PER_CPU(struct kvm_steal_time, steal_time) __aligned(64); +static int has_steal_clock = 0; static struct kvm_para_state *kvm_para_state(void) { @@ -441,6 +452,21 @@ static void __init paravirt_ops_setup(void) #endif } +static void kvm_register_steal_time(void) +{ + int cpu = smp_processor_id(); + struct kvm_steal_time *st = &per_cpu(steal_time, cpu); + + if (!has_steal_clock) + return; + + memset(st, 0, sizeof(*st)); + + wrmsrl(MSR_KVM_STEAL_TIME, (__pa(st) | KVM_MSR_ENABLED)); + printk(KERN_INFO "kvm-stealtime: cpu %d, msr %lx\n", + cpu, __pa(st)); +} + void __cpuinit kvm_guest_cpu_init(void) { if (!kvm_para_available()) @@ -457,6 +483,9 @@ void __cpuinit kvm_guest_cpu_init(void) printk(KERN_INFO"KVM setup async PF for cpu %d\n", smp_processor_id()); } + + if (has_steal_clock) + kvm_register_steal_time(); } static void kvm_pv_disable_apf(void *unused) @@ -483,6 +512,31 @@ static struct notifier_block kvm_pv_reboot_nb = { .notifier_call = kvm_pv_reboot_notify, }; +static u64 kvm_steal_clock(int cpu) +{ + u64 steal; + struct kvm_steal_time *src; + int version; + + src = &per_cpu(steal_time, cpu); + do { + version = src->version; + rmb(); + steal = src->steal; + rmb(); + } while ((version & 1) || (version != src->version)); + + return steal; +} + +void kvm_disable_steal_time(void) +{ + if (!has_steal_clock) + return; + + wrmsr(MSR_KVM_STEAL_TIME, 0, 0); +} + #ifdef CONFIG_SMP static void __init kvm_smp_prepare_boot_cpu(void) { @@ -500,6 +554,7 @@ static void __cpuinit kvm_guest_cpu_online(void *dummy) static void kvm_guest_cpu_offline(void *dummy) { + kvm_disable_steal_time(); kvm_pv_disable_apf(NULL); apf_task_wake_all(); } @@ -548,6 +603,11 @@ void __init kvm_guest_init(void) if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF)) x86_init.irqs.trap_init = kvm_apf_trap_init; + if (kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) { + has_steal_clock = 1; + pv_time_ops.steal_clock = kvm_steal_clock; + } + #ifdef CONFIG_SMP smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu; register_cpu_notifier(&kvm_cpu_notifier); @@ -555,3 +615,15 @@ void __init kvm_guest_init(void) kvm_guest_cpu_init(); #endif } + +static __init int activate_jump_labels(void) +{ + if (has_steal_clock) { + jump_label_inc(¶virt_steal_enabled); + if (steal_acc) + jump_label_inc(¶virt_steal_rq_enabled); + } + + return 0; +} +arch_initcall(activate_jump_labels); diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 6389a6bca11b8159e47eab9feff42b828f666fc2..c1a0188e29aef61d22706c8d0f2b99f843cf8fc7 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -160,6 +160,7 @@ static void __cpuinit kvm_setup_secondary_clock(void) static void kvm_crash_shutdown(struct pt_regs *regs) { native_write_msr(msr_kvm_system_time, 0, 0); + kvm_disable_steal_time(); native_machine_crash_shutdown(regs); } #endif @@ -167,6 +168,7 @@ static void kvm_crash_shutdown(struct pt_regs *regs) static void kvm_shutdown(void) { native_write_msr(msr_kvm_system_time, 0, 0); + kvm_disable_steal_time(); native_machine_shutdown(); }