On Mon, 19 Nov 2018 18:25:33 +0100
Michael Mueller <mimu@xxxxxxxxxxxxx> wrote:
> This function processes a gib alert list. It is required to
> run when either a gib alert interruption has been received or
> a gisa that might be in the alert list is cleared or dropped.
>
> Signed-off-by: Michael Mueller <mimu@xxxxxxxxxxxxx>
> ---
> arch/s390/kvm/interrupt.c | 28 ++++++++++++++++++++++++++++
> 1 file changed, 28 insertions(+)
>
> diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
> index 8676596f6b5c..443d1804d611 100644
> --- a/arch/s390/kvm/interrupt.c
> +++ b/arch/s390/kvm/interrupt.c
> @@ -2910,6 +2910,34 @@ static void nullify_gisa(struct kvm_s390_gisa *gisa)
> gisa->next_alert = (u32)(u64)gisa;
> }
>
> +/*
> + * Before processing, the gib alert list needs to be cut-off from
> + * the gib by means of function unlink_gib_alert_list(). If non NULL,
> + * the list is processed from its latest to oldest entry.
> + *
> + * Processing an gisa entry needs to wake-up a vcpu of the kvm this gisa
> + * belongs to. Thus, the pending guest interruption will be processed
> + * in SIE context.
> + */
> +static void __maybe_unused process_gib_alert_list(void)
> +{
> + struct kvm_s390_gisa *gisa = unlink_gib_alert_list();
> + struct kvm_s390_gisa *next_alert;
> + struct kvm_vcpu *vcpu;
> + struct kvm *kvm;
> +
> + for (; gisa; gisa = next_alert) {
> + next_alert = (struct kvm_s390_gisa *)(u64)gisa->next_alert;
> + /* unlink from alert list */
> + gisa->next_alert = (u32)(u64)gisa;
> + /* wake-up a vcpu of the kvm this gisa belongs to */
> + kvm = container_of(gisa, struct sie_page2, gisa)->kvm;
> + vcpu = __find_vcpu_for_floating_irq(kvm);
> + if (vcpu)
> + kvm_s390_vcpu_wakeup(vcpu);
Just to check if I understood correctly: This loop is where you'll add
the extra check whether the interrupt has already been delivered, right?
> + }
> +}
> +
> void kvm_s390_gisa_clear(struct kvm *kvm)
> {
> if (kvm->arch.gisa) {
