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| author | Wanpeng Li <wanpeng.li@hotmail.com> | 2017-10-05 18:54:24 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2017-10-12 14:01:50 +0200 |
| commit | ccbfa1d39b9e6d6e578176d091362287c53c7d4d (patch) | |
| tree | 030ae2be7e60a89342ca302725317c94162d71f9 /arch/x86/kvm/lapic.c | |
| parent | c69518c86be5000bf4d8eb0e0d279d40779d2a18 (diff) | |
| download | linux-ccbfa1d39b9e6d6e578176d091362287c53c7d4d.tar.gz | |
KVM: LAPIC: Introduce limit_periodic_timer_frequency
Extract the logic of limit lapic periodic timer frequency to a new function, this function will be used by later patches. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch/x86/kvm/lapic.c')
| -rw-r--r-- | arch/x86/kvm/lapic.c | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 6723e2ca3d9d..8841bb539c90 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1301,6 +1301,27 @@ static void update_divide_count(struct kvm_lapic *apic) apic->divide_count); } +static void limit_periodic_timer_frequency(struct kvm_lapic *apic) +{ + /* + * Do not allow the guest to program periodic timers with small + * interval, since the hrtimers are not throttled by the host + * scheduler. + */ + if (apic_lvtt_period(apic)) { + s64 min_period = min_timer_period_us * 1000LL; + + if (apic->lapic_timer.period < min_period) { + pr_info_ratelimited( + "kvm: vcpu %i: requested %lld ns " + "lapic timer period limited to %lld ns\n", + apic->vcpu->vcpu_id, + apic->lapic_timer.period, min_period); + apic->lapic_timer.period = min_period; + } + } +} + static void apic_update_lvtt(struct kvm_lapic *apic) { u32 timer_mode = kvm_lapic_get_reg(apic, APIC_LVTT) & @@ -1445,23 +1466,7 @@ static bool set_target_expiration(struct kvm_lapic *apic) if (!apic->lapic_timer.period) return false; - /* - * Do not allow the guest to program periodic timers with small - * interval, since the hrtimers are not throttled by the host - * scheduler. - */ - if (apic_lvtt_period(apic)) { - s64 min_period = min_timer_period_us * 1000LL; - - if (apic->lapic_timer.period < min_period) { - pr_info_ratelimited( - "kvm: vcpu %i: requested %lld ns " - "lapic timer period limited to %lld ns\n", - apic->vcpu->vcpu_id, - apic->lapic_timer.period, min_period); - apic->lapic_timer.period = min_period; - } - } + limit_periodic_timer_frequency(apic); apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016" PRIx64 ", " |