Commit 26d05b36 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

Merge branch 'kvm-async-pf-int' into HEAD

parents 0ed076c7 b1d40575

arch/x86/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -802,6 +802,7 @@ config KVM_GUEST 
	depends on PARAVIRT

	select PARAVIRT_CLOCK

	select ARCH_CPUIDLE_HALTPOLL

	select X86_HV_CALLBACK_VECTOR

	default y

	help

	  This option enables various optimizations for running under the KVM

arch/x86/include/asm/idtentry.h

+4 −0
Original line number Diff line number Diff line
@@ -647,6 +647,10 @@ DECLARE_IDTENTRY_SYSVEC(HYPERVISOR_CALLBACK_VECTOR, sysvec_acrn_hv_callback); 
DECLARE_IDTENTRY_SYSVEC(HYPERVISOR_CALLBACK_VECTOR,	sysvec_xen_hvm_callback);

#endif



#ifdef CONFIG_KVM_GUEST

DECLARE_IDTENTRY_SYSVEC(HYPERVISOR_CALLBACK_VECTOR,	sysvec_kvm_asyncpf_interrupt);

#endif



#undef X86_TRAP_OTHER



#endif

arch/x86/include/asm/kvm_para.h

+1 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 


#include <asm/processor.h>

#include <asm/alternative.h>

#include <linux/interrupt.h>

#include <uapi/asm/kvm_para.h>



extern void kvmclock_init(void);

arch/x86/kernel/kvm.c

+34 −13
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 


#include <linux/context_tracking.h>

#include <linux/init.h>

#include <linux/irq.h>

#include <linux/kernel.h>

#include <linux/kvm_para.h>

#include <linux/cpu.h>
@@ -232,16 +233,11 @@ EXPORT_SYMBOL_GPL(kvm_read_and_reset_apf_flags); 


noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token)

{

	u32 reason = kvm_read_and_reset_apf_flags();

	u32 flags = kvm_read_and_reset_apf_flags();

	bool rcu_exit;



	switch (reason) {

	case KVM_PV_REASON_PAGE_NOT_PRESENT:

	case KVM_PV_REASON_PAGE_READY:

		break;

	default:

	if (!flags)

		return false;

	}



	rcu_exit = idtentry_enter_cond_rcu(regs);

	instrumentation_begin();
@@ -254,13 +250,13 @@ noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token) 
	if (unlikely(!(regs->flags & X86_EFLAGS_IF)))

		panic("Host injected async #PF in interrupt disabled region\n");



	if (reason == KVM_PV_REASON_PAGE_NOT_PRESENT) {

	if (flags & KVM_PV_REASON_PAGE_NOT_PRESENT) {

		if (unlikely(!(user_mode(regs))))

			panic("Host injected async #PF in kernel mode\n");

		/* Page is swapped out by the host. */

		kvm_async_pf_task_wait_schedule(token);

	} else {

		kvm_async_pf_task_wake(token);

		WARN_ONCE(1, "Unexpected async PF flags: %x\n", flags);

	}



	instrumentation_end();
@@ -268,6 +264,27 @@ noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token) 
	return true;

}



DEFINE_IDTENTRY_SYSVEC(sysvec_kvm_asyncpf_interrupt)

{

	struct pt_regs *old_regs = set_irq_regs(regs);

	u32 token;

	bool rcu_exit;



	rcu_exit = idtentry_enter_cond_rcu(regs);



	inc_irq_stat(irq_hv_callback_count);



	if (__this_cpu_read(apf_reason.enabled)) {

		token = __this_cpu_read(apf_reason.token);

		kvm_async_pf_task_wake(token);

		__this_cpu_write(apf_reason.token, 0);

		wrmsrl(MSR_KVM_ASYNC_PF_ACK, 1);

	}



	idtentry_exit_cond_rcu(regs, rcu_exit);

	set_irq_regs(old_regs);

}



static void __init paravirt_ops_setup(void)

{

	pv_info.name = "KVM";
@@ -311,17 +328,19 @@ static notrace void kvm_guest_apic_eoi_write(u32 reg, u32 val) 


static void kvm_guest_cpu_init(void)

{

	if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF) && kvmapf) {

		u64 pa;

	if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF_INT) && kvmapf) {

		u64 pa = slow_virt_to_phys(this_cpu_ptr(&apf_reason));



		WARN_ON_ONCE(!static_branch_likely(&kvm_async_pf_enabled));



		pa = slow_virt_to_phys(this_cpu_ptr(&apf_reason));

		pa |= KVM_ASYNC_PF_ENABLED;

		pa |= KVM_ASYNC_PF_ENABLED | KVM_ASYNC_PF_DELIVERY_AS_INT;



		if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF_VMEXIT))

			pa |= KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT;



		wrmsrl(MSR_KVM_ASYNC_PF_INT, HYPERVISOR_CALLBACK_VECTOR);



		wrmsrl(MSR_KVM_ASYNC_PF_EN, pa);

		__this_cpu_write(apf_reason.enabled, 1);

		pr_info("KVM setup async PF for cpu %d\n", smp_processor_id());
@@ -646,8 +665,10 @@ static void __init kvm_guest_init(void) 
	if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))

		apic_set_eoi_write(kvm_guest_apic_eoi_write);



	if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF) && kvmapf)

	if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF_INT) && kvmapf) {

		static_branch_enable(&kvm_async_pf_enabled);

		alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_kvm_asyncpf_interrupt);

	}



#ifdef CONFIG_SMP

	smp_ops.smp_prepare_cpus = kvm_smp_prepare_cpus;