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From:   Roman Kagan <rkagan@virtuozzo.com>
To:     Vitaly Kuznetsov <vkuznets@redhat.com>
CC:     "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        =?iso-8859-2?Q?Radim_Kr=E8m=E1=F8?= <rkrcmar@redhat.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "K. Y. Srinivasan" <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        "x86@kernel.org" <x86@kernel.org>,
        "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com>
Subject: Re: [PATCH v2 3/4] x86/kvm/hyper-v: direct mode for synthetic timers
Thread-Topic: [PATCH v2 3/4] x86/kvm/hyper-v: direct mode for synthetic timers
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Date:   Mon, 3 Dec 2018 17:12:24 +0000
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On Mon, Nov 26, 2018 at 04:47:31PM +0100, Vitaly Kuznetsov wrote:
> @@ -379,6 +398,14 @@ void kvm_hv_synic_send_eoi(struct kvm_vcpu *vcpu, in=
t vector)
>  	for (i =3D 0; i < ARRAY_SIZE(synic->sint); i++)
>  		if (synic_get_sint_vector(synic_read_sint(synic, i)) =3D=3D vector)
>  			kvm_hv_notify_acked_sint(vcpu, i);
> +
> +	for (i =3D 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++) {
> +		stimer =3D &hv_vcpu->stimer[i];
> +		if (stimer->msg_pending && stimer->config.enable &&
> +		    stimer->config.direct_mode &&
> +		    stimer->config.apic_vector =3D=3D vector)
> +			stimer_mark_pending(stimer, false);
> +	}
>  }

While debugging another issue with synic timers, it just occurred to me
that with direct timers no extra processing is necessary on EOI: unlike
traditional synic timers which may have failed to deliver a message and
want to be notified when they can retry, direct timers just set the irq
directly in the apic.

So this hunk shouldn't be needed, should it?

Roman.