linux-kernel - Re: [PATCH v2] KVM: LAPIC: Loose fluctuation filter for auto tune lapic_timer_advance

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+CySCXpn=CUnfUYf+r4aAFOOVscryLQqDnYhTstb4Hv=Hw@mail.gmail.com>
Date:   Thu, 26 Sep 2019 18:34:26 +0800
From:   Wanpeng Li <kernellwp@...il.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     LKML <linux-kernel@...r.kernel.org>, kvm <kvm@...r.kernel.org>,
        Radim Krčmář <rkrcmar@...hat.com>,
        Sean Christopherson <sean.j.christopherson@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>
Subject: Re: [PATCH v2] KVM: LAPIC: Loose fluctuation filter for auto tune lapic_timer_advance_ns

On Thu, 26 Sep 2019 at 18:25, Paolo Bonzini <pbonzini@...hat.com> wrote:
>
> On 26/09/19 02:54, Wanpeng Li wrote:
> > -#define LAPIC_TIMER_ADVANCE_ADJUST_MIN 100
> > -#define LAPIC_TIMER_ADVANCE_ADJUST_MAX 5000
> > -#define LAPIC_TIMER_ADVANCE_ADJUST_INIT 1000
> > +#define LAPIC_TIMER_ADVANCE_EXPIRE_MIN       100
> > +#define LAPIC_TIMER_ADVANCE_EXPIRE_MAX       10000
> > +#define LAPIC_TIMER_ADVANCE_NS_INIT  1000
> > +#define LAPIC_TIMER_ADVANCE_NS_MAX     5000
>
> I think the old #define value is good.  What about:
>
> -#define LAPIC_TIMER_ADVANCE_ADJUST_MIN 100
> -#define LAPIC_TIMER_ADVANCE_ADJUST_MAX 5000
> -#define LAPIC_TIMER_ADVANCE_ADJUST_INIT 1000
> +#define LAPIC_TIMER_ADVANCE_ADJUST_MIN 100     /* clock cycles */
> +#define LAPIC_TIMER_ADVANCE_ADJUST_MAX 10000   /* clock cycles */
> +#define LAPIC_TIMER_ADVANCE_NS_INIT    1000
> +#define LAPIC_TIMER_ADVANCE_NS_MAX     5000

Looks good, I guess you can update the patch during apply. :)

    Wanpeng