From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2989AC43387 for ; Thu, 20 Dec 2018 12:21:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F014B21741 for ; Thu, 20 Dec 2018 12:21:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731884AbeLTMVi (ORCPT ); Thu, 20 Dec 2018 07:21:38 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57904 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729161AbeLTMVi (ORCPT ); Thu, 20 Dec 2018 07:21:38 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D197FC07C570; Thu, 20 Dec 2018 12:21:37 +0000 (UTC) Received: from gondolin (dhcp-192-187.str.redhat.com [10.33.192.187]) by smtp.corp.redhat.com (Postfix) with ESMTP id 39EB6600C0; Thu, 20 Dec 2018 12:21:33 +0000 (UTC) Date: Thu, 20 Dec 2018 13:21:30 +0100 From: Cornelia Huck To: Michael Mueller Cc: KVM Mailing List , Linux-S390 Mailing List , linux-kernel@vger.kernel.org, Martin Schwidefsky , Heiko Carstens , Christian Borntraeger , Janosch Frank , David Hildenbrand , Halil Pasic , Pierre Morel Subject: Re: [PATCH v5 05/15] KVM: s390: unify pending_irqs() and pending_irqs_no_gisa() Message-ID: <20181220132130.33a417fa.cohuck@redhat.com> In-Reply-To: <62bf4bcf-585f-ddfc-e7a5-18fc946819d9@linux.ibm.com> References: <20181219191756.57973-1-mimu@linux.ibm.com> <20181219191756.57973-6-mimu@linux.ibm.com> <20181220120614.65acacac.cohuck@redhat.com> <62bf4bcf-585f-ddfc-e7a5-18fc946819d9@linux.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Thu, 20 Dec 2018 12:21:38 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 20 Dec 2018 12:49:56 +0100 Michael Mueller wrote: > On 20.12.18 12:06, Cornelia Huck wrote: > > On Wed, 19 Dec 2018 20:17:46 +0100 > > Michael Mueller wrote: > > > >> Use a single function with parameter irq_flags to differentiate > >> between cases. > >> > >> New irq flag: > >> IRQ_FLAG_LOCAL: include vcpu local interruptions pending > >> IRQ_FLAG_FLOATING: include vcpu floating interruptions pending > >> IRQ_FLAG_GISA: include GISA interruptions pending in IPM > > > > I presume that means that irqs may be in more than one set? Or are gisa > > irqs not considered floating irqs, because they use a different > > mechanism? > > Currently, the interruptions managed in GISA are floating only. But > that might change in future. The idea is not to subsume IRQ_FLAG_GISA > in IRQ_FLAG_FLOATING but to be able to address the right set of > procedures to determine the irq pending set for a given subset of irq > types that have different implementations. > > There might be a better name for IRQ_FLAG_FLOATING then? So the split is: - local interrupts that are pending via kvm structures; - floating interrupts that are pending via kvm structures; - interrupts that are pending via gisa? If so, what about - IRQ_FLAG_KVM_LOCAL - IRQ_FLAG_KVM_FLOATING - IRQ_FLAG_GISA (or maybe IRQ_FLAG_GISA_FLOATING, if you need to distinguish those later on?) > > > > >> > >> New irq masks: > >> IRQ_MASK_ALL: include all types > >> IRQ_MASK_NO_GISA: include all types but GISA > >> > >> Examples: > >> pending_irqs(vcpu, IRQ_MASK_ALL) > >> pending_irqs(vcpu, IRQ_MASK_NO_GISA) > >> > >> There will be more irq flags with upcoming patches. > >> > >> Signed-off-by: Michael Mueller > >> --- > >> arch/s390/kvm/interrupt.c | 33 +++++++++++++++++++++------------ > >> 1 file changed, 21 insertions(+), 12 deletions(-) > >> > >> diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c > >> index 093b568b6356..4ab20d2eb180 100644 > >> --- a/arch/s390/kvm/interrupt.c > >> +++ b/arch/s390/kvm/interrupt.c > >> @@ -31,6 +31,13 @@ > >> #define PFAULT_DONE 0x0680 > >> #define VIRTIO_PARAM 0x0d00 > >> > >> +#define IRQ_FLAG_LOCAL 0x8000 /* include local interruption pending mask */ > >> +#define IRQ_FLAG_FLOATING 0x4000 /* include float interruption pending mask */ > >> +#define IRQ_FLAG_GISA 0x2000 /* include GISA interruption pending mask */ > >> + > >> +#define IRQ_MASK_ALL (IRQ_FLAG_LOCAL | IRQ_FLAG_FLOATING | IRQ_FLAG_GISA) > >> +#define IRQ_MASK_NO_GISA (IRQ_MASK_ALL & ~IRQ_FLAG_GISA) > >> + > >> /* handle external calls via sigp interpretation facility */ > >> static int sca_ext_call_pending(struct kvm_vcpu *vcpu, int *src_id) > >> { > >> @@ -237,16 +244,18 @@ static inline int kvm_s390_gisa_tac_ipm_gisc(struct kvm_s390_gisa *gisa, u32 gis > >> return test_and_clear_bit_inv(IPM_BIT_OFFSET + gisc, (unsigned long *) gisa); > >> } > >> > >> -static inline unsigned long pending_irqs_no_gisa(struct kvm_vcpu *vcpu) > >> +static inline unsigned long pending_irqs(struct kvm_vcpu *vcpu, u16 irq_flags) > > > > Any deeper reason why this is a u16? 16 bits should be enough for > > everyone? :) > > I want to use the 8 bits for the IRQ type and the other 8 for additional > controls, see: "KVM: s390: restore IAM in get_ipm() when IPM is clean" Still need to look at that patch, but my question mainly was "why only 16 bits"? I would think making this local variable larger is cheap. > > > > >> { > >> - return vcpu->kvm->arch.float_int.pending_irqs | > >> - vcpu->arch.local_int.pending_irqs; > >> -}