linux-kernel - Re: [PATCH v4 0/3] KVM: Introduce dedicated vCPUs hint KVM_HINTS

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CANRm+Cy5bi-=5fz_raea1vxSpsGWB8C2xknYN5baRZGRzAPsMw@mail.gmail.com>
Date:   Wed, 7 Mar 2018 08:41:33 +0800
From:   Wanpeng Li <kernellwp@...il.com>
To:     Eduardo Valentin <eduval@...zon.com>
Cc:     LKML <linux-kernel@...r.kernel.org>, kvm <kvm@...r.kernel.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Radim Krčmář <rkrcmar@...hat.com>,
        Eduardo Habkost <ehabkost@...hat.com>
Subject: Re: [PATCH v4 0/3] KVM: Introduce dedicated vCPUs hint KVM_HINTS_DEDICATED

2018-03-06 22:39 GMT+08:00 Eduardo Valentin <eduval@...zon.com>:
> Folks,
>
> On Tue, Feb 13, 2018 at 09:05:39AM +0800, Wanpeng Li wrote:
>> This patchset introduces dedicated vCPUs(vCPU pinning, and there is no
>> vCPU over-commitment) hint KVM_HINTS_DEDICATED, it has two users now:
>>
>> 1) Waiman Long mentioned that:
>>
>>     Generally speaking, unfair lock performs well for VMs with a small
>>     number of vCPUs. Native qspinlock may perform better than pvqspinlock
>>     if there is vCPU pinning and there is no vCPU over-commitment.
>>
>> 2) vCPUs are very unlikely to get preempted when they are the only task
>>    running on a CPU. PV TLB flush is slower that the native flush in that
>>    case.
>>
>> v3 -> v4:
>>  * update feature bit document
>> v2 -> v3:
>>  * a separate table for CPUID[0x40000001].EDX bits
>>  * a new kvm_hint_has_feature macro
>> v1 -> v2:
>>  * update to KVM_HINTS_DEDICATED
>
> Great to see this has finally moved forward! Thanks for picking it up Wanpeng.
>
> I would just request to next time at least reference the original thread and
> copy the original authors of the patch/idea.

Thanks for the original idea, Eduardo!

Regards,
Wanpeng Li