KVM Archive on lore.kernel.org
 help / color / Atom feed
From: Tao Xu <tao3.xu@intel.com>
To: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: pbonzini@redhat.com, rkrcmar@redhat.com, corbet@lwn.net,
	tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
	hpa@zytor.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	fenghua.yu@intel.com, xiaoyao.li@linux.intel.com,
	jingqi.liu@intel.com
Subject: Re: [PATCH v7 1/3] KVM: x86: add support for user wait instructions
Date: Mon, 15 Jul 2019 09:11:31 +0800
Message-ID: <72e39861-7af4-057c-f879-4cc5a363e3e4@intel.com> (raw)
In-Reply-To: <20190712151300.GB29659@linux.intel.com>

On 7/12/2019 11:13 PM, Sean Christopherson wrote:
> On Fri, Jul 12, 2019 at 04:29:05PM +0800, Tao Xu wrote:
>> diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
>> index 46af3a5e9209..a4d5da34b306 100644
>> --- a/arch/x86/kvm/vmx/nested.c
>> +++ b/arch/x86/kvm/vmx/nested.c
>> @@ -2048,6 +2048,7 @@ static void prepare_vmcs02_early(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12)
>>   				  SECONDARY_EXEC_ENABLE_INVPCID |
>>   				  SECONDARY_EXEC_RDTSCP |
>>   				  SECONDARY_EXEC_XSAVES |
>> +				  SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE |
>>   				  SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
>>   				  SECONDARY_EXEC_APIC_REGISTER_VIRT |
>>   				  SECONDARY_EXEC_ENABLE_VMFUNC);
>> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
>> index d98eac371c0a..f411c9ae5589 100644
>> --- a/arch/x86/kvm/vmx/vmx.c
>> +++ b/arch/x86/kvm/vmx/vmx.c
>> @@ -2247,6 +2247,7 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
>>   			SECONDARY_EXEC_RDRAND_EXITING |
>>   			SECONDARY_EXEC_ENABLE_PML |
>>   			SECONDARY_EXEC_TSC_SCALING |
>> +			SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE |
>>   			SECONDARY_EXEC_PT_USE_GPA |
>>   			SECONDARY_EXEC_PT_CONCEAL_VMX |
>>   			SECONDARY_EXEC_ENABLE_VMFUNC |
>> @@ -3984,6 +3985,25 @@ static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx)
>>   		}
>>   	}
>>   
>> +	if (vmcs_config.cpu_based_2nd_exec_ctrl &
>> +		SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE) {
> 
> This should be aligned with the beginning of the conditional.
> Alternatively, add a vmx_waitpkg_supported() helper, which is fairly
> ubiquitous even when there is only a single call site.
> 

OK, Thank you for your suggestion.
>> +		/* Exposing WAITPKG only when WAITPKG is exposed */
> No need for this comment.  It's also oddly worded, e.g. the second
> "exposed" should probably be "enabled"?
> 
>> +		bool waitpkg_enabled =
>> +			guest_cpuid_has(vcpu, X86_FEATURE_WAITPKG);
>> +
>> +		if (!waitpkg_enabled)
>> +			exec_control &= ~SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE;
>> +
>> +		if (nested) {
>> +			if (waitpkg_enabled)
>> +				vmx->nested.msrs.secondary_ctls_high |=
>> +					SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE;
>> +			else
>> +				vmx->nested.msrs.secondary_ctls_high &=
>> +					~SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE;
>> +		}
>> +	}
>> +
>>   	vmx->secondary_exec_control = exec_control;
>>   }
>>   
>> -- 
>> 2.20.1
>>


  reply index

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-12  8:29 [PATCH v7 0/3] KVM: x86: Enable " Tao Xu
2019-07-12  8:29 ` [PATCH v7 1/3] KVM: x86: add support for " Tao Xu
2019-07-12 15:13   ` Sean Christopherson
2019-07-15  1:11     ` Tao Xu [this message]
2019-07-12  8:29 ` [PATCH v7 2/3] KVM: vmx: Emulate MSR IA32_UMWAIT_CONTROL Tao Xu
2019-07-12 15:52   ` Sean Christopherson
2019-07-15  1:22     ` Tao Xu
2019-07-15 14:16       ` Sean Christopherson
2019-07-16 16:03   ` Eduardo Habkost
2019-07-17  1:17     ` Tao Xu
2019-07-17  2:03       ` Tao Xu
2019-07-12  8:29 ` [PATCH v7 3/3] KVM: vmx: handle vm-exit for UMWAIT and TPAUSE Tao Xu
2019-07-12 16:03   ` Sean Christopherson
2019-07-13 14:22     ` Tao Xu

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=72e39861-7af4-057c-f879-4cc5a363e3e4@intel.com \
    --to=tao3.xu@intel.com \
    --cc=bp@alien8.de \
    --cc=corbet@lwn.net \
    --cc=fenghua.yu@intel.com \
    --cc=hpa@zytor.com \
    --cc=jingqi.liu@intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=rkrcmar@redhat.com \
    --cc=sean.j.christopherson@intel.com \
    --cc=tglx@linutronix.de \
    --cc=xiaoyao.li@linux.intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

KVM Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/kvm/0 kvm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 kvm kvm/ https://lore.kernel.org/kvm \
		kvm@vger.kernel.org kvm@archiver.kernel.org
	public-inbox-index kvm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.kvm


AGPL code for this site: git clone https://public-inbox.org/ public-inbox