From: Zachary Amsden <zamsden@redhat.com>
To: KVM <kvm@vger.kernel.org>, Avi Kivity <avi@redhat.com>,
Marcelo Tosatti <mtosatti@redhat.com>,
Glauber Costa <glommer@redhat.com>
Cc: Linux-kernel <linux-kernel@vger.kernel.org>,
Zachary Amsden <zamsden@redhat.com>
Subject: [PATCH 16/18] Use getnsboottime in KVM
Date: Mon, 12 Jul 2010 16:08:10 -1000 [thread overview]
Message-ID: <1278986892-11733-17-git-send-email-zamsden@redhat.com> (raw)
In-Reply-To: <1278986892-11733-1-git-send-email-zamsden@redhat.com>
Signed-off-by: Zachary Amsden <zamsden@redhat.com>
---
arch/x86/kvm/x86.c | 22 ++++++----------------
1 files changed, 6 insertions(+), 16 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7b9fdf3..c55cdf9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -891,16 +891,6 @@ static void kvm_set_time_scale(uint32_t tsc_khz, struct pvclock_vcpu_time_info *
hv_clock->tsc_to_system_mul);
}
-static inline u64 get_kernel_ns(void)
-{
- struct timespec ts;
-
- WARN_ON(preemptible());
- ktime_get_ts(&ts);
- monotonic_to_bootbased(&ts);
- return timespec_to_ns(&ts);
-}
-
static DEFINE_PER_CPU(unsigned long, cpu_tsc_khz);
static inline int kvm_tsc_changes_freq(void)
@@ -929,7 +919,7 @@ void guest_write_tsc(struct kvm_vcpu *vcpu, u64 data)
spin_lock(&kvm->arch.tsc_write_lock);
offset = data - native_read_tsc();
- ns = get_kernel_ns();
+ ns = getnsboottime();
elapsed = ns - kvm->arch.last_tsc_nsec;
sdiff = data - kvm->arch.last_tsc_write;
if (sdiff < 0)
@@ -982,7 +972,7 @@ static int kvm_write_guest_time(struct kvm_vcpu *v)
/* Keep irq disabled to prevent changes to the clock */
local_irq_save(flags);
kvm_get_msr(v, MSR_IA32_TSC, &tsc_timestamp);
- kernel_ns = get_kernel_ns();
+ kernel_ns = getnsboottime();
this_tsc_khz = __get_cpu_var(cpu_tsc_khz);
local_irq_restore(flags);
@@ -1927,7 +1917,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
if (check_tsc_unstable()) {
/* Subtract elapsed cycle time */
u64 ns = !vcpu->arch.last_host_ns ? 0 :
- get_kernel_ns() - vcpu->arch.last_host_ns;
+ getnsboottime() - vcpu->arch.last_host_ns;
tsc_delta -= nsec_to_cycles(ns);
kvm_x86_ops->adjust_tsc_offset(vcpu, -tsc_delta);
}
@@ -1942,7 +1932,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
kvm_x86_ops->vcpu_put(vcpu);
kvm_put_guest_fpu(vcpu);
vcpu->arch.last_host_tsc = native_read_tsc();
- vcpu->arch.last_host_ns = get_kernel_ns();
+ vcpu->arch.last_host_ns = getnsboottime();
}
static int is_efer_nx(void)
@@ -3335,7 +3325,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
goto out;
r = 0;
- now_ns = get_kernel_ns();
+ now_ns = getnsboottime();
delta = user_ns.clock - now_ns;
kvm->arch.kvmclock_offset = delta;
break;
@@ -3344,7 +3334,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
struct kvm_clock_data user_ns;
u64 now_ns;
- now_ns = get_kernel_ns();
+ now_ns = getnsboottime();
user_ns.clock = kvm->arch.kvmclock_offset + now_ns;
user_ns.flags = 0;
--
1.7.1
next prev parent reply other threads:[~2010-07-13 2:10 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-13 2:07 KVM timekeeping fixes Zachary Amsden
2010-07-13 2:07 ` [PATCH 01/18] Make TSC offset writes non-preemptible Zachary Amsden
2010-07-13 2:07 ` [PATCH 02/18] Fix SVM VMCB reset Zachary Amsden
2010-07-13 2:07 ` [PATCH 03/18] TSC reset compensation Zachary Amsden
2010-07-13 2:07 ` [PATCH 04/18] Robust TSC compensation Zachary Amsden
2010-07-13 2:07 ` [PATCH 05/18] Make cpu_tsc_khz updates use local CPU Zachary Amsden
2010-07-13 2:08 ` [PATCH 06/18] Warn about unstable TSC Zachary Amsden
2010-07-13 2:08 ` [PATCH 07/18] Unify TSC logic Zachary Amsden
2010-07-13 2:08 ` [PATCH 08/18] Fix deep C-state TSC desynchronization Zachary Amsden
2010-07-13 2:08 ` [PATCH 09/18] Add helper functions for time computation Zachary Amsden
2010-07-13 2:08 ` [PATCH 10/18] Keep SMP VMs more in sync on unstable TSC Zachary Amsden
2010-07-13 2:08 ` [PATCH 11/18] Perform hardware_enable in CPU_STARTING callback Zachary Amsden
2010-07-13 2:08 ` [PATCH 12/18] Add clock sync request to hardware enable Zachary Amsden
2010-07-13 2:08 ` [PATCH 13/18] Move scale_delta into common header Zachary Amsden
2010-07-13 2:08 ` [PATCH 14/18] Fix a possible backwards warp of kvmclock Zachary Amsden
2010-07-13 2:08 ` [PATCH 15/18] Implement getnsboottime kernel API Zachary Amsden
2010-07-13 2:08 ` Zachary Amsden [this message]
2010-07-13 2:08 ` [PATCH 17/18] Indicate reliable TSC in kvmclock Zachary Amsden
2010-07-13 2:08 ` [PATCH 18/18] Add timekeeping documentation Zachary Amsden
-- strict thread matches above, loose matches on Subject: below --
2010-07-13 2:25 KVM timekeeping fixes, V2 Zachary Amsden
2010-07-13 2:25 ` [PATCH 16/18] Use getnsboottime in KVM Zachary Amsden
2010-07-15 2:43 ` Rik van Riel
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