mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-23 08:02:37 +07:00
199b5763d3
If a vcpu exits due to request a user mode spinlock, then the spinlock-holder may be preempted in user mode or kernel mode. (Note that not all architectures trap spin loops in user mode, only AMD x86 and ARM/ARM64 currently do). But if a vcpu exits in kernel mode, then the holder must be preempted in kernel mode, so we should choose a vcpu in kernel mode as a more likely candidate for the lock holder. This introduces kvm_arch_vcpu_in_kernel() to decide whether the vcpu is in kernel-mode when it's preempted. kvm_vcpu_on_spin's new argument says the same of the spinning VCPU. Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
179 lines
4.7 KiB
C
179 lines
4.7 KiB
C
/*
|
|
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
|
|
* Author: Christoffer Dall <c.dall@virtualopensystems.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License, version 2, as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#include <linux/kvm.h>
|
|
#include <linux/kvm_host.h>
|
|
#include <asm/kvm_emulate.h>
|
|
#include <asm/kvm_coproc.h>
|
|
#include <asm/kvm_mmu.h>
|
|
#include <asm/kvm_psci.h>
|
|
#include <trace/events/kvm.h>
|
|
|
|
#include "trace.h"
|
|
|
|
typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *);
|
|
|
|
static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run)
|
|
{
|
|
int ret;
|
|
|
|
trace_kvm_hvc(*vcpu_pc(vcpu), *vcpu_reg(vcpu, 0),
|
|
kvm_vcpu_hvc_get_imm(vcpu));
|
|
vcpu->stat.hvc_exit_stat++;
|
|
|
|
ret = kvm_psci_call(vcpu);
|
|
if (ret < 0) {
|
|
kvm_inject_undefined(vcpu);
|
|
return 1;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
|
|
{
|
|
kvm_inject_undefined(vcpu);
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* kvm_handle_wfx - handle a WFI or WFE instructions trapped in guests
|
|
* @vcpu: the vcpu pointer
|
|
* @run: the kvm_run structure pointer
|
|
*
|
|
* WFE: Yield the CPU and come back to this vcpu when the scheduler
|
|
* decides to.
|
|
* WFI: Simply call kvm_vcpu_block(), which will halt execution of
|
|
* world-switches and schedule other host processes until there is an
|
|
* incoming IRQ or FIQ to the VM.
|
|
*/
|
|
static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run)
|
|
{
|
|
if (kvm_vcpu_get_hsr(vcpu) & HSR_WFI_IS_WFE) {
|
|
trace_kvm_wfx(*vcpu_pc(vcpu), true);
|
|
vcpu->stat.wfe_exit_stat++;
|
|
kvm_vcpu_on_spin(vcpu, false);
|
|
} else {
|
|
trace_kvm_wfx(*vcpu_pc(vcpu), false);
|
|
vcpu->stat.wfi_exit_stat++;
|
|
kvm_vcpu_block(vcpu);
|
|
kvm_clear_request(KVM_REQ_UNHALT, vcpu);
|
|
}
|
|
|
|
kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int kvm_handle_unknown_ec(struct kvm_vcpu *vcpu, struct kvm_run *run)
|
|
{
|
|
u32 hsr = kvm_vcpu_get_hsr(vcpu);
|
|
|
|
kvm_pr_unimpl("Unknown exception class: hsr: %#08x\n",
|
|
hsr);
|
|
|
|
kvm_inject_undefined(vcpu);
|
|
return 1;
|
|
}
|
|
|
|
static exit_handle_fn arm_exit_handlers[] = {
|
|
[0 ... HSR_EC_MAX] = kvm_handle_unknown_ec,
|
|
[HSR_EC_WFI] = kvm_handle_wfx,
|
|
[HSR_EC_CP15_32] = kvm_handle_cp15_32,
|
|
[HSR_EC_CP15_64] = kvm_handle_cp15_64,
|
|
[HSR_EC_CP14_MR] = kvm_handle_cp14_32,
|
|
[HSR_EC_CP14_LS] = kvm_handle_cp14_load_store,
|
|
[HSR_EC_CP14_64] = kvm_handle_cp14_64,
|
|
[HSR_EC_CP_0_13] = kvm_handle_cp_0_13_access,
|
|
[HSR_EC_CP10_ID] = kvm_handle_cp10_id,
|
|
[HSR_EC_HVC] = handle_hvc,
|
|
[HSR_EC_SMC] = handle_smc,
|
|
[HSR_EC_IABT] = kvm_handle_guest_abort,
|
|
[HSR_EC_DABT] = kvm_handle_guest_abort,
|
|
};
|
|
|
|
static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
|
|
{
|
|
u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
|
|
|
|
return arm_exit_handlers[hsr_ec];
|
|
}
|
|
|
|
/*
|
|
* Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
|
|
* proper exit to userspace.
|
|
*/
|
|
int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
|
|
int exception_index)
|
|
{
|
|
exit_handle_fn exit_handler;
|
|
|
|
if (ARM_ABORT_PENDING(exception_index)) {
|
|
u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
|
|
|
|
/*
|
|
* HVC/SMC already have an adjusted PC, which we need
|
|
* to correct in order to return to after having
|
|
* injected the abort.
|
|
*/
|
|
if (hsr_ec == HSR_EC_HVC || hsr_ec == HSR_EC_SMC) {
|
|
u32 adj = kvm_vcpu_trap_il_is32bit(vcpu) ? 4 : 2;
|
|
*vcpu_pc(vcpu) -= adj;
|
|
}
|
|
|
|
kvm_inject_vabt(vcpu);
|
|
return 1;
|
|
}
|
|
|
|
exception_index = ARM_EXCEPTION_CODE(exception_index);
|
|
|
|
switch (exception_index) {
|
|
case ARM_EXCEPTION_IRQ:
|
|
return 1;
|
|
case ARM_EXCEPTION_HVC:
|
|
/*
|
|
* See ARM ARM B1.14.1: "Hyp traps on instructions
|
|
* that fail their condition code check"
|
|
*/
|
|
if (!kvm_condition_valid(vcpu)) {
|
|
kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
|
|
return 1;
|
|
}
|
|
|
|
exit_handler = kvm_get_exit_handler(vcpu);
|
|
|
|
return exit_handler(vcpu, run);
|
|
case ARM_EXCEPTION_DATA_ABORT:
|
|
kvm_inject_vabt(vcpu);
|
|
return 1;
|
|
case ARM_EXCEPTION_HYP_GONE:
|
|
/*
|
|
* HYP has been reset to the hyp-stub. This happens
|
|
* when a guest is pre-empted by kvm_reboot()'s
|
|
* shutdown call.
|
|
*/
|
|
run->exit_reason = KVM_EXIT_FAIL_ENTRY;
|
|
return 0;
|
|
default:
|
|
kvm_pr_unimpl("Unsupported exception type: %d",
|
|
exception_index);
|
|
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
|
|
return 0;
|
|
}
|
|
}
|