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From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: rkrcmar@redhat.com, wanpeng.li@hotmail.com
Subject: [PATCH 0/3] KVM: lapic: optimize injection of already-expired timer
Date: Thu, 29 Jun 2017 18:58:18 +0200	[thread overview]
Message-ID: <1498755501-39602-1-git-send-email-pbonzini@redhat.com> (raw)

This is my take on Wanpeng's optimization, whose effect I've now measured
with vmexit.flat.  Indeed, without patch 3 the new tscdeadline_immed
benchmark is 50% slower with preemption_timer=1 than with preemption_timer=0.

Patch 1 refactors start_hv_timer to prepare for the next one and to
simplify Wanpeng's patch (a lot).  Patch 2 avoids a bug that I didn't
catch in my earlier review: kvm_x86_ops->set_timer must not be called
directly when the TSC goes backwards.

Paolo

Paolo Bonzini (2):
  KVM: lapic: reorganize start_hv_timer
  KVM: lapic: reorganize restart_apic_timer

Wanpeng Li (1):
  KVM: LAPIC: Fix lapic timer injection delay

 arch/x86/kvm/lapic.c | 116 ++++++++++++++++++++++++++++-----------------------
 arch/x86/kvm/lapic.h |   2 +-
 arch/x86/kvm/vmx.c   |   3 +-
 arch/x86/kvm/x86.c   |   8 ++--
 4 files changed, 71 insertions(+), 58 deletions(-)

-- 
1.8.3.1

             reply	other threads:[~2017-06-29 16:58 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-29 16:58 Paolo Bonzini [this message]
2017-06-29 16:58 ` [PATCH 1/3] KVM: lapic: reorganize start_hv_timer Paolo Bonzini
2017-06-29 16:58 ` [PATCH 2/3] KVM: lapic: reorganize restart_apic_timer Paolo Bonzini
2017-06-29 16:58 ` [PATCH 3/3] KVM: LAPIC: Fix lapic timer injection delay Paolo Bonzini
2017-07-02  1:35   ` Wanpeng Li
2017-07-02  1:56     ` Wanpeng Li
2017-07-03  7:30       ` Paolo Bonzini
2017-07-03  8:08         ` Wanpeng Li
2017-07-03  8:16           ` Paolo Bonzini
2017-07-03  8:41             ` Wanpeng Li
2017-06-30  1:30 ` [PATCH 0/3] KVM: lapic: optimize injection of already-expired timer Wanpeng Li

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