Merge branch 'topic/ppc-kvm' into next

Merge some KVM commits we are keeping in our topic branch.
This commit is contained in:
Michael Ellerman 2022-09-30 18:35:16 +10:00
commit 9511b5a033
2 changed files with 76 additions and 33 deletions

View File

@ -249,6 +249,7 @@ static void kvmppc_fast_vcpu_kick_hv(struct kvm_vcpu *vcpu)
/*
* We use the vcpu_load/put functions to measure stolen time.
*
* Stolen time is counted as time when either the vcpu is able to
* run as part of a virtual core, but the task running the vcore
* is preempted or sleeping, or when the vcpu needs something done
@ -278,6 +279,12 @@ static void kvmppc_fast_vcpu_kick_hv(struct kvm_vcpu *vcpu)
* lock. The stolen times are measured in units of timebase ticks.
* (Note that the != TB_NIL checks below are purely defensive;
* they should never fail.)
*
* The POWER9 path is simpler, one vcpu per virtual core so the
* former case does not exist. If a vcpu is preempted when it is
* BUSY_IN_HOST and not ceded or otherwise blocked, then accumulate
* the stolen cycles in busy_stolen. RUNNING is not a preemptible
* state in the P9 path.
*/
static void kvmppc_core_start_stolen(struct kvmppc_vcore *vc, u64 tb)
@ -311,8 +318,14 @@ static void kvmppc_core_vcpu_load_hv(struct kvm_vcpu *vcpu, int cpu)
unsigned long flags;
u64 now;
if (cpu_has_feature(CPU_FTR_ARCH_300))
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
if (vcpu->arch.busy_preempt != TB_NIL) {
WARN_ON_ONCE(vcpu->arch.state != KVMPPC_VCPU_BUSY_IN_HOST);
vc->stolen_tb += mftb() - vcpu->arch.busy_preempt;
vcpu->arch.busy_preempt = TB_NIL;
}
return;
}
now = mftb();
@ -340,8 +353,21 @@ static void kvmppc_core_vcpu_put_hv(struct kvm_vcpu *vcpu)
unsigned long flags;
u64 now;
if (cpu_has_feature(CPU_FTR_ARCH_300))
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
/*
* In the P9 path, RUNNABLE is not preemptible
* (nor takes host interrupts)
*/
WARN_ON_ONCE(vcpu->arch.state == KVMPPC_VCPU_RUNNABLE);
/*
* Account stolen time when preempted while the vcpu task is
* running in the kernel (but not in qemu, which is INACTIVE).
*/
if (task_is_running(current) &&
vcpu->arch.state == KVMPPC_VCPU_BUSY_IN_HOST)
vcpu->arch.busy_preempt = mftb();
return;
}
now = mftb();
@ -740,6 +766,18 @@ static void __kvmppc_create_dtl_entry(struct kvm_vcpu *vcpu,
vcpu->arch.dtl.dirty = true;
}
static void kvmppc_create_dtl_entry_p9(struct kvm_vcpu *vcpu,
struct kvmppc_vcore *vc,
u64 now)
{
unsigned long stolen;
stolen = vc->stolen_tb - vcpu->arch.stolen_logged;
vcpu->arch.stolen_logged = vc->stolen_tb;
__kvmppc_create_dtl_entry(vcpu, vc->pcpu, now, stolen);
}
static void kvmppc_create_dtl_entry(struct kvm_vcpu *vcpu,
struct kvmppc_vcore *vc)
{
@ -2517,10 +2555,24 @@ static int kvmppc_set_one_reg_hv(struct kvm_vcpu *vcpu, u64 id,
r = set_vpa(vcpu, &vcpu->arch.dtl, addr, len);
break;
case KVM_REG_PPC_TB_OFFSET:
{
/* round up to multiple of 2^24 */
vcpu->arch.vcore->tb_offset =
ALIGN(set_reg_val(id, *val), 1UL << 24);
u64 tb_offset = ALIGN(set_reg_val(id, *val), 1UL << 24);
/*
* Now that we know the timebase offset, update the
* decrementer expiry with a guest timebase value. If
* the userspace does not set DEC_EXPIRY, this ensures
* a migrated vcpu at least starts with an expired
* decrementer, which is better than a large one that
* causes a hang.
*/
if (!vcpu->arch.dec_expires && tb_offset)
vcpu->arch.dec_expires = get_tb() + tb_offset;
vcpu->arch.vcore->tb_offset = tb_offset;
break;
}
case KVM_REG_PPC_LPCR:
kvmppc_set_lpcr(vcpu, set_reg_val(id, *val), true);
break;
@ -3840,23 +3892,17 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
for (sub = 0; sub < core_info.n_subcores; ++sub)
spin_unlock(&core_info.vc[sub]->lock);
guest_enter_irqoff();
guest_timing_enter_irqoff();
srcu_idx = srcu_read_lock(&vc->kvm->srcu);
guest_state_enter_irqoff();
this_cpu_disable_ftrace();
/*
* Interrupts will be enabled once we get into the guest,
* so tell lockdep that we're about to enable interrupts.
*/
trace_hardirqs_on();
trap = __kvmppc_vcore_entry();
trace_hardirqs_off();
this_cpu_enable_ftrace();
guest_state_exit_irqoff();
srcu_read_unlock(&vc->kvm->srcu, srcu_idx);
@ -3891,11 +3937,10 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
kvmppc_set_host_core(pcpu);
context_tracking_guest_exit();
if (!vtime_accounting_enabled_this_cpu()) {
local_irq_enable();
/*
* Service IRQs here before vtime_account_guest_exit() so any
* Service IRQs here before guest_timing_exit_irqoff() so any
* ticks that occurred while running the guest are accounted to
* the guest. If vtime accounting is enabled, accounting uses
* TB rather than ticks, so it can be done without enabling
@ -3904,7 +3949,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
*/
local_irq_disable();
}
vtime_account_guest_exit();
guest_timing_exit_irqoff();
local_irq_enable();
@ -4520,7 +4565,6 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
vc = vcpu->arch.vcore;
vcpu->arch.ceded = 0;
vcpu->arch.run_task = current;
vcpu->arch.state = KVMPPC_VCPU_RUNNABLE;
vcpu->arch.last_inst = KVM_INST_FETCH_FAILED;
/* See if the MMU is ready to go */
@ -4547,6 +4591,8 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
/* flags save not required, but irq_pmu has no disable/enable API */
powerpc_local_irq_pmu_save(flags);
vcpu->arch.state = KVMPPC_VCPU_RUNNABLE;
if (signal_pending(current))
goto sigpend;
if (need_resched() || !kvm->arch.mmu_ready)
@ -4591,47 +4637,44 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
tb = mftb();
__kvmppc_create_dtl_entry(vcpu, pcpu, tb + vc->tb_offset, 0);
kvmppc_create_dtl_entry_p9(vcpu, vc, tb + vc->tb_offset);
trace_kvm_guest_enter(vcpu);
guest_enter_irqoff();
guest_timing_enter_irqoff();
srcu_idx = srcu_read_lock(&kvm->srcu);
guest_state_enter_irqoff();
this_cpu_disable_ftrace();
/* Tell lockdep that we're about to enable interrupts */
trace_hardirqs_on();
trap = kvmhv_p9_guest_entry(vcpu, time_limit, lpcr, &tb);
vcpu->arch.trap = trap;
trace_hardirqs_off();
this_cpu_enable_ftrace();
guest_state_exit_irqoff();
srcu_read_unlock(&kvm->srcu, srcu_idx);
set_irq_happened(trap);
context_tracking_guest_exit();
vcpu->cpu = -1;
vcpu->arch.thread_cpu = -1;
vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
if (!vtime_accounting_enabled_this_cpu()) {
local_irq_enable();
powerpc_local_irq_pmu_restore(flags);
/*
* Service IRQs here before vtime_account_guest_exit() so any
* Service IRQs here before guest_timing_exit_irqoff() so any
* ticks that occurred while running the guest are accounted to
* the guest. If vtime accounting is enabled, accounting uses
* TB rather than ticks, so it can be done without enabling
* interrupts here, which has the problem that it accounts
* interrupt processing overhead to the host.
*/
local_irq_disable();
powerpc_local_irq_pmu_save(flags);
}
vtime_account_guest_exit();
vcpu->cpu = -1;
vcpu->arch.thread_cpu = -1;
guest_timing_exit_irqoff();
powerpc_local_irq_pmu_restore(flags);
@ -4694,6 +4737,7 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
out:
vcpu->cpu = -1;
vcpu->arch.thread_cpu = -1;
vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
powerpc_local_irq_pmu_restore(flags);
preempt_enable();
goto done;

View File

@ -786,7 +786,6 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
hrtimer_init(&vcpu->arch.dec_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
vcpu->arch.dec_timer.function = kvmppc_decrementer_wakeup;
vcpu->arch.dec_expires = get_tb();
#ifdef CONFIG_KVM_EXIT_TIMING
mutex_init(&vcpu->arch.exit_timing_lock);