From: Glauber Costa <glommer@redhat.com>
To: kvm@vger.kernel.org
Cc: avi@redhat.com, zamsden@redhat.com, mtosatti@redhat.com,
riel@redhat.com, peterz@infradead.org, mingo@elte.hu,
jeremy@goop.org
Subject: [RFC v2 3/7] measure time out of guest
Date: Mon, 30 Aug 2010 12:06:22 -0400 [thread overview]
Message-ID: <1283184391-7785-7-git-send-email-glommer@redhat.com> (raw)
In-Reply-To: <1283184391-7785-6-git-send-email-glommer@redhat.com>
By measuring time between a vcpu_put and a vcpu_load, we can
estimate how much time did the guest stay out of the cpu.
This is exported to the guest at every clock update.
Signed-off-by: Glauber Costa <glommer@redhat.com>
---
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/x86.c | 13 +++++++++++--
2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 502e53f..bc28aff 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -364,6 +364,8 @@ struct kvm_vcpu_arch {
u64 hv_vapic;
cpumask_var_t wbinvd_dirty_mask;
+ u64 time_out;
+ u64 last_time_out;
};
struct kvm_arch {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f4b77ea..9d08032 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -906,6 +906,7 @@ static void kvm_write_guest_time(struct kvm_vcpu *v, bool update_time)
if ((!vcpu->time_page))
return;
+ vcpu->hv_clock.steal_time = vcpu->time_out / 1000000;
if (!update_time)
return;
@@ -928,8 +929,7 @@ static void kvm_write_guest_time(struct kvm_vcpu *v, bool update_time)
vcpu->hv_clock.system_time = ts.tv_nsec +
(NSEC_PER_SEC * (u64)ts.tv_sec) + v->kvm->arch.kvmclock_offset;
- vcpu->hv_clock.flags = 0;
-
+ vcpu->hv_clock.flags = PVCLOCK_STEAL_BIT;
/*
* The interface expects us to write an even number signaling that the
* update is finished. Since the guest won't see the intermediate
@@ -1801,6 +1801,8 @@ static bool need_emulate_wbinvd(struct kvm_vcpu *vcpu)
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
+ s64 now;
+
/* Address WBINVD may be executed by guest */
if (need_emulate_wbinvd(vcpu)) {
if (kvm_x86_ops->has_wbinvd_exit())
@@ -1818,12 +1820,19 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
per_cpu(cpu_tsc_khz, cpu) = khz;
}
kvm_request_guest_time_update(vcpu);
+
+ now = getnsboottime();
+
+ if (vcpu->arch.last_time_out != 0)
+ vcpu->arch.time_out += now - vcpu->arch.last_time_out;
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
kvm_x86_ops->vcpu_put(vcpu);
kvm_put_guest_fpu(vcpu);
+
+ vcpu->arch.last_time_out = getnsboottime();
}
static int is_efer_nx(void)
--
1.6.2.2
next prev parent reply other threads:[~2010-08-30 16:23 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-30 16:06 [RFC v2 0/7] kvm stael time implementation Glauber Costa
2010-08-30 16:06 ` [RFC v2 1/7] change headers preparing for steal time Glauber Costa
2010-08-30 16:06 ` [RFC 1/8] Implement getnsboottime kernel API Glauber Costa
2010-08-30 16:06 ` [RFC v2 2/7] always call kvm_write_guest Glauber Costa
2010-08-30 16:06 ` [RFC 2/8] change headers preparing for steal time Glauber Costa
2010-08-30 16:06 ` [RFC 3/8] always call kvm_write_guest Glauber Costa
2010-08-30 16:06 ` Glauber Costa [this message]
2010-08-30 16:06 ` [RFC v2 4/7] change kernel accounting to include steal time Glauber Costa
2010-08-30 16:06 ` [RFC 4/8] measure time out of guest Glauber Costa
2010-08-30 16:06 ` [RFC 5/8] change kernel accounting to include steal time Glauber Costa
2010-08-30 16:06 ` [RFC v2 5/7] kvm steal time implementation Glauber Costa
2010-08-30 16:06 ` [RFC 6/8] " Glauber Costa
2010-08-30 16:06 ` [RFC v2 6/7] touch softlockup watchdog Glauber Costa
2010-08-30 16:06 ` [RFC v2 7/7] tell guest about steal time feature Glauber Costa
2010-08-30 16:06 ` [RFC 7/8] touch softlockup watchdog Glauber Costa
2010-08-30 16:06 ` [RFC 8/8] tell guest about steal time feature Glauber Costa
2010-08-30 17:33 ` [RFC v2 6/7] touch softlockup watchdog Jeremy Fitzhardinge
2010-08-30 18:07 ` Glauber Costa
2010-08-30 16:46 ` [RFC 5/8] change kernel accounting to include steal time Peter Zijlstra
2010-08-30 17:26 ` Glauber Costa
2010-08-30 17:30 ` [RFC v2 4/7] " Jeremy Fitzhardinge
2010-08-30 18:39 ` Rik van Riel
2010-08-30 19:07 ` Jeremy Fitzhardinge
2010-08-30 19:14 ` Peter Zijlstra
2010-08-30 19:17 ` Rik van Riel
2010-08-30 19:20 ` Peter Zijlstra
2010-08-30 19:45 ` Rik van Riel
2010-08-30 22:56 ` Jeremy Fitzhardinge
2010-08-30 23:03 ` Rik van Riel
2010-08-31 8:11 ` Peter Zijlstra
2010-09-02 18:19 ` Glauber Costa
2010-09-03 3:24 ` Jeremy Fitzhardinge
2010-09-03 7:18 ` Peter Zijlstra
2010-09-01 23:56 ` [RFC 1/8] Implement getnsboottime kernel API Zachary Amsden
2010-08-30 16:37 ` [RFC v2 0/7] kvm stael time implementation Peter Zijlstra
2010-08-30 16:45 ` Jeremy Fitzhardinge
2010-08-30 17:21 ` Glauber Costa
2010-08-30 17:20 ` Jeremy Fitzhardinge
2010-08-30 17:06 [RFC v2 0/7] kvm steal time implementation proposal Glauber Costa
2010-08-30 17:06 ` [RFC v2 3/7] measure time out of guest Glauber Costa
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