Re: [PATCH v2 0/3] Provides userspace with per-VM capability to improve latency
From: Wanpeng Li
Date: Wed Mar 14 2018 - 21:48:40 EST
2018-03-15 0:11 GMT+08:00 Paolo Bonzini <pbonzini@xxxxxxxxxx>:
> On 12/03/2018 12:53, Wanpeng Li wrote:
>> Provides userspace with per-VM capability(KVM_CAP_X86_DISABLE_EXITS) to
>> not intercept MWAIT/HLT/PAUSE in order that to improve latency in some
>> workloads.
>>
>> The patchset implements the original proposal from Radim.
>> https://www.spinics.net/lists/kvm/msg146879.html
>>
>> In addition, thanks to Jan H. SchÃnherr's attempt last year.
>>
>> v1 -> v2:
>> * remove blinding setting KVM_ENABLE_CAP statement in doc
>> * move PV_UNHALT associated statement to 2/3
>> * rename kvm_mwait_can_in_guest to kvm_can_mwait_in_guest
>> * remove unconditionally set INTERCEPT HLT in svm
>> * call vmx_clear_hlt() from pre_enter_smm()
>> * add a check to kvm_update_cpuid() that forbits KVM_FEATURE_PV_UNHALT
>> when halt exits are disabld
>>
>> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
>> Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
>> Cc: Jan H. SchÃnherr <jschoenh@xxxxxxxxx>
>>
>> Wanpeng Li (3):
>> KVM: X86: Provides userspace with a capability to not intercept MWAIT
>> KVM: X86: Provides userspace with a capability to not intercept HLT
>> KVM: X86: Provides userspace with a capability to not intercept PAUSE
>>
>> Documentation/virtual/kvm/api.txt | 24 ++++++++++++-------
>> arch/x86/include/asm/kvm_host.h | 4 ++++
>> arch/x86/kvm/cpuid.c | 5 ++++
>> arch/x86/kvm/svm.c | 9 ++++---
>> arch/x86/kvm/vmx.c | 50 ++++++++++++++++++++++++++++++++-------
>> arch/x86/kvm/x86.c | 29 +++++++++++++++++++----
>> arch/x86/kvm/x86.h | 24 +++++++++++++++----
>> include/uapi/linux/kvm.h | 2 +-
>> tools/include/uapi/linux/kvm.h | 2 +-
>> 9 files changed, 118 insertions(+), 31 deletions(-)
>>
>
> Queued, thanks.
Thanks Paolo. :)
>Do you have QEMU patches to automatically enable this
> together with HINTS_DEDICATED?
I will cook the patches. :)
Regards,
Wanpeng Li