diff options
Diffstat (limited to 'arch/x86/kernel/kvm.c')
| -rw-r--r-- | arch/x86/kernel/kvm.c | 56 |
1 files changed, 38 insertions, 18 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index edbbfc854e39..14f65a5f938e 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -42,7 +42,6 @@ #include <asm/traps.h> #include <asm/desc.h> #include <asm/tlbflush.h> -#include <asm/idle.h> #include <asm/apic.h> #include <asm/apicdef.h> #include <asm/hypervisor.h> @@ -267,13 +266,11 @@ do_async_page_fault(struct pt_regs *regs, unsigned long error_code) case KVM_PV_REASON_PAGE_NOT_PRESENT: /* page is swapped out by the host. */ prev_state = exception_enter(); - exit_idle(); kvm_async_pf_task_wait((u32)read_cr2()); exception_exit(prev_state); break; case KVM_PV_REASON_PAGE_READY: rcu_irq_enter(); - exit_idle(); kvm_async_pf_task_wake((u32)read_cr2()); rcu_irq_exit(); break; @@ -308,7 +305,7 @@ static void kvm_register_steal_time(void) static DEFINE_PER_CPU(unsigned long, kvm_apic_eoi) = KVM_PV_EOI_DISABLED; -static void kvm_guest_apic_eoi_write(u32 reg, u32 val) +static notrace void kvm_guest_apic_eoi_write(u32 reg, u32 val) { /** * This relies on __test_and_clear_bit to modify the memory @@ -319,7 +316,7 @@ static void kvm_guest_apic_eoi_write(u32 reg, u32 val) */ if (__test_and_clear_bit(KVM_PV_EOI_BIT, this_cpu_ptr(&kvm_apic_eoi))) return; - apic_write(APIC_EOI, APIC_EOI_ACK); + apic->native_eoi_write(APIC_EOI, APIC_EOI_ACK); } static void kvm_guest_cpu_init(void) @@ -592,6 +589,38 @@ out: local_irq_restore(flags); } +#ifdef CONFIG_X86_32 +__visible bool __kvm_vcpu_is_preempted(long cpu) +{ + struct kvm_steal_time *src = &per_cpu(steal_time, cpu); + + return !!src->preempted; +} +PV_CALLEE_SAVE_REGS_THUNK(__kvm_vcpu_is_preempted); + +#else + +#include <asm/asm-offsets.h> + +extern bool __raw_callee_save___kvm_vcpu_is_preempted(long); + +/* + * Hand-optimize version for x86-64 to avoid 8 64-bit register saving and + * restoring to/from the stack. + */ +asm( +".pushsection .text;" +".global __raw_callee_save___kvm_vcpu_is_preempted;" +".type __raw_callee_save___kvm_vcpu_is_preempted, @function;" +"__raw_callee_save___kvm_vcpu_is_preempted:" +"movq __per_cpu_offset(,%rdi,8), %rax;" +"cmpb $0, " __stringify(KVM_STEAL_TIME_preempted) "+steal_time(%rax);" +"setne %al;" +"ret;" +".popsection"); + +#endif + /* * Setup pv_lock_ops to exploit KVM_FEATURE_PV_UNHALT if present. */ @@ -608,20 +637,11 @@ void __init kvm_spinlock_init(void) pv_lock_ops.queued_spin_unlock = PV_CALLEE_SAVE(__pv_queued_spin_unlock); pv_lock_ops.wait = kvm_wait; pv_lock_ops.kick = kvm_kick_cpu; -} -static __init int kvm_spinlock_init_jump(void) -{ - if (!kvm_para_available()) - return 0; - if (!kvm_para_has_feature(KVM_FEATURE_PV_UNHALT)) - return 0; - - static_key_slow_inc(¶virt_ticketlocks_enabled); - printk(KERN_INFO "KVM setup paravirtual spinlock\n"); - - return 0; + if (kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) { + pv_lock_ops.vcpu_is_preempted = + PV_CALLEE_SAVE(__kvm_vcpu_is_preempted); + } } -early_initcall(kvm_spinlock_init_jump); #endif /* CONFIG_PARAVIRT_SPINLOCKS */ |