From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751810Ab2GIGWl (ORCPT ); Mon, 9 Jul 2012 02:22:41 -0400 Received: from e23smtp05.au.ibm.com ([202.81.31.147]:36244 "EHLO e23smtp05.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751411Ab2GIGWj (ORCPT ); Mon, 9 Jul 2012 02:22:39 -0400 From: Raghavendra K T To: "H. Peter Anvin" , Thomas Gleixner , Avi Kivity , Ingo Molnar , Marcelo Tosatti , Rik van Riel Cc: S390 , Carsten Otte , Christian Borntraeger , KVM , Raghavendra K T , chegu vinod , "Andrew M. Theurer" , LKML , X86 , Gleb Natapov , linux390@de.ibm.com, Srivatsa Vaddagiri , Joerg Roedel Date: Mon, 09 Jul 2012 11:50:33 +0530 Message-Id: <20120709062032.24030.10454.sendpatchset@codeblue> In-Reply-To: <20120709062012.24030.37154.sendpatchset@codeblue> References: <20120709062012.24030.37154.sendpatchset@codeblue> Subject: [PATCH RFC 1/2] kvm vcpu: Note down pause loop exit x-cbid: 12070820-1396-0000-0000-000001879672 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Raghavendra K T Noting pause loop exited vcpu helps in filtering right candidate to yield. Yielding to same vcpu may result in more wastage of cpu. From: Raghavendra K T --- arch/x86/include/asm/kvm_host.h | 7 +++++++ arch/x86/kvm/svm.c | 1 + arch/x86/kvm/vmx.c | 1 + arch/x86/kvm/x86.c | 4 +++- 4 files changed, 12 insertions(+), 1 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index db7c1f2..857ca68 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -484,6 +484,13 @@ struct kvm_vcpu_arch { u64 length; u64 status; } osvw; + + /* Pause loop exit optimization */ + struct { + bool pause_loop_exited; + bool dy_eligible; + } plo; + }; struct kvm_lpage_info { diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index f75af40..a492f5d 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -3264,6 +3264,7 @@ static int interrupt_window_interception(struct vcpu_svm *svm) static int pause_interception(struct vcpu_svm *svm) { + svm->vcpu.arch.plo.pause_loop_exited = true; kvm_vcpu_on_spin(&(svm->vcpu)); return 1; } diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 32eb588..600fb3c 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -4945,6 +4945,7 @@ out: static int handle_pause(struct kvm_vcpu *vcpu) { skip_emulated_instruction(vcpu); + vcpu->arch.plo.pause_loop_exited = true; kvm_vcpu_on_spin(vcpu); return 1; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index be6d549..07dbd14 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5331,7 +5331,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) if (req_immediate_exit) smp_send_reschedule(vcpu->cpu); - + vcpu->arch.plo.pause_loop_exited = false; kvm_guest_enter(); if (unlikely(vcpu->arch.switch_db_regs)) { @@ -6168,6 +6168,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) BUG_ON(vcpu->kvm == NULL); kvm = vcpu->kvm; + vcpu->arch.plo.pause_loop_exited = false; + vcpu->arch.plo.dy_eligible = true; vcpu->arch.emulate_ctxt.ops = &emulate_ops; if (!irqchip_in_kernel(kvm) || kvm_vcpu_is_bsp(vcpu)) vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;