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Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r--arch/x86/kvm/x86.c68
1 files changed, 60 insertions, 8 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 171ff4d1b7cb..fb2bc9f5fe96 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2854,7 +2854,11 @@ static inline u64 vgettsc(struct pvclock_clock *clock, u64 *tsc_timestamp,
return v * clock->mult;
}
-static int do_monotonic_raw(s64 *t, u64 *tsc_timestamp)
+/*
+ * As with get_kvmclock_base_ns(), this counts from boot time, at the
+ * frequency of CLOCK_MONOTONIC_RAW (hence adding gtos->offs_boot).
+ */
+static int do_kvmclock_base(s64 *t, u64 *tsc_timestamp)
{
struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
unsigned long seq;
@@ -2873,6 +2877,29 @@ static int do_monotonic_raw(s64 *t, u64 *tsc_timestamp)
return mode;
}
+/*
+ * This calculates CLOCK_MONOTONIC at the time of the TSC snapshot, with
+ * no boot time offset.
+ */
+static int do_monotonic(s64 *t, u64 *tsc_timestamp)
+{
+ struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
+ unsigned long seq;
+ int mode;
+ u64 ns;
+
+ do {
+ seq = read_seqcount_begin(&gtod->seq);
+ ns = gtod->clock.base_cycles;
+ ns += vgettsc(&gtod->clock, tsc_timestamp, &mode);
+ ns >>= gtod->clock.shift;
+ ns += ktime_to_ns(gtod->clock.offset);
+ } while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
+ *t = ns;
+
+ return mode;
+}
+
static int do_realtime(struct timespec64 *ts, u64 *tsc_timestamp)
{
struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
@@ -2894,18 +2921,42 @@ static int do_realtime(struct timespec64 *ts, u64 *tsc_timestamp)
return mode;
}
-/* returns true if host is using TSC based clocksource */
+/*
+ * Calculates the kvmclock_base_ns (CLOCK_MONOTONIC_RAW + boot time) and
+ * reports the TSC value from which it do so. Returns true if host is
+ * using TSC based clocksource.
+ */
static bool kvm_get_time_and_clockread(s64 *kernel_ns, u64 *tsc_timestamp)
{
/* checked again under seqlock below */
if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode))
return false;
- return gtod_is_based_on_tsc(do_monotonic_raw(kernel_ns,
- tsc_timestamp));
+ return gtod_is_based_on_tsc(do_kvmclock_base(kernel_ns,
+ tsc_timestamp));
}
-/* returns true if host is using TSC based clocksource */
+/*
+ * Calculates CLOCK_MONOTONIC and reports the TSC value from which it did
+ * so. Returns true if host is using TSC based clocksource.
+ */
+bool kvm_get_monotonic_and_clockread(s64 *kernel_ns, u64 *tsc_timestamp)
+{
+ /* checked again under seqlock below */
+ if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode))
+ return false;
+
+ return gtod_is_based_on_tsc(do_monotonic(kernel_ns,
+ tsc_timestamp));
+}
+
+/*
+ * Calculates CLOCK_REALTIME and reports the TSC value from which it did
+ * so. Returns true if host is using TSC based clocksource.
+ *
+ * DO NOT USE this for anything related to migration. You want CLOCK_TAI
+ * for that.
+ */
static bool kvm_get_walltime_and_clockread(struct timespec64 *ts,
u64 *tsc_timestamp)
{
@@ -3152,7 +3203,7 @@ static void kvm_setup_guest_pvclock(struct kvm_vcpu *v,
guest_hv_clock->version = ++vcpu->hv_clock.version;
- mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT);
+ kvm_gpc_mark_dirty_in_slot(gpc);
read_unlock_irqrestore(&gpc->lock, flags);
trace_kvm_pvclock_update(v->vcpu_id, &vcpu->hv_clock);
@@ -4674,7 +4725,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
KVM_XEN_HVM_CONFIG_SHARED_INFO |
KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL |
KVM_XEN_HVM_CONFIG_EVTCHN_SEND |
- KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE;
+ KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE |
+ KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA;
if (sched_info_on())
r |= KVM_XEN_HVM_CONFIG_RUNSTATE |
KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_FLAG;
@@ -12027,7 +12079,7 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
vcpu->arch.regs_avail = ~0;
vcpu->arch.regs_dirty = ~0;
- kvm_gpc_init(&vcpu->arch.pv_time, vcpu->kvm, vcpu, KVM_HOST_USES_PFN);
+ kvm_gpc_init(&vcpu->arch.pv_time, vcpu->kvm);
if (!irqchip_in_kernel(vcpu->kvm) || kvm_vcpu_is_reset_bsp(vcpu))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;