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Subject[PATCH 3/4] KVM: x86: pass kvm_get_time_scale arguments in hertz
Date
Prepare for improving the precision in the next patch.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/x86.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6db3c219795b..e0bf8f10dc22 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1203,7 +1203,7 @@ static uint32_t div_frac(uint32_t dividend, uint32_t divisor)
return dividend;
}

-static void kvm_get_time_scale(uint32_t scaled_khz, uint32_t base_khz,
+static void kvm_get_time_scale(uint64_t scaled_hz, uint64_t base_hz,
s8 *pshift, u32 *pmultiplier)
{
uint64_t scaled64;
@@ -1211,8 +1211,8 @@ static void kvm_get_time_scale(uint32_t scaled_khz, uint32_t base_khz,
uint64_t tps64;
uint32_t tps32;

- tps64 = base_khz * 1000LL;
- scaled64 = scaled_khz * 1000LL;
+ tps64 = base_hz;
+ scaled64 = scaled_hz;
while (tps64 > scaled64*2 || tps64 & 0xffffffff00000000ULL) {
tps64 >>= 1;
shift--;
@@ -1230,8 +1230,8 @@ static void kvm_get_time_scale(uint32_t scaled_khz, uint32_t base_khz,
*pshift = shift;
*pmultiplier = div_frac(scaled64, tps32);

- pr_debug("%s: base_khz %u => %u, shift %d, mul %u\n",
- __func__, base_khz, scaled_khz, shift, *pmultiplier);
+ pr_debug("%s: base_hz %llu => %llu, shift %d, mul %u\n",
+ __func__, base_hz, scaled_hz, shift, *pmultiplier);
}

#ifdef CONFIG_X86_64
@@ -1303,7 +1303,7 @@ static int kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz)
}

/* Compute a scale to convert nanoseconds in TSC cycles */
- kvm_get_time_scale(user_tsc_khz, NSEC_PER_SEC / 1000,
+ kvm_get_time_scale(user_tsc_khz * 1000LL, NSEC_PER_SEC,
&vcpu->arch.virtual_tsc_shift,
&vcpu->arch.virtual_tsc_mult);
vcpu->arch.virtual_tsc_khz = user_tsc_khz;
@@ -1779,7 +1779,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
tgt_tsc_khz = kvm_scale_tsc(v, tgt_tsc_khz);

if (unlikely(vcpu->hw_tsc_khz != tgt_tsc_khz)) {
- kvm_get_time_scale(NSEC_PER_SEC / 1000, tgt_tsc_khz,
+ kvm_get_time_scale(NSEC_PER_SEC, tgt_tsc_khz * 1000LL,
&vcpu->hv_clock.tsc_shift,
&vcpu->hv_clock.tsc_to_system_mul);
vcpu->hw_tsc_khz = tgt_tsc_khz;
--
1.8.3.1

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