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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 7075AC433E0 for ; Thu, 6 Aug 2020 17:56:38 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 98238206B2 for ; Thu, 6 Aug 2020 17:56:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 98238206B2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kaod.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52820 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k3k85-0006if-8J for qemu-devel@archiver.kernel.org; Thu, 06 Aug 2020 13:56:37 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53650) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k3k7G-000624-Ho; Thu, 06 Aug 2020 13:55:46 -0400 Received: from smtpout1.mo804.mail-out.ovh.net ([79.137.123.220]:57789) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k3k7C-0005KU-WD; Thu, 06 Aug 2020 13:55:46 -0400 Received: from mxplan5.mail.ovh.net (unknown [10.109.146.59]) by mo804.mail-out.ovh.net (Postfix) with ESMTPS id 3556B5475BDA; Thu, 6 Aug 2020 19:55:31 +0200 (CEST) Received: from kaod.org (37.59.142.99) by DAG4EX1.mxp5.local (172.16.2.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Thu, 6 Aug 2020 19:55:30 +0200 Authentication-Results: garm.ovh; auth=pass (GARM-99G003cabd08b2-0e58-4f73-a075-b57124cc823a, 96EDEDBD7B7627A0205C40E9E2B74F8D513A659B) smtp.auth=clg@kaod.org Subject: Re: [PATCH v2 for-5.2 3/5] ppc/xive: Introduce dedicated kvm_irqchip_in_kernel() wrappers To: Greg Kurz , David Gibson References: <159673295739.766512.2950380687630225803.stgit@bahia.lan> <159673298011.766512.17389427967409788911.stgit@bahia.lan> From: =?UTF-8?Q?C=c3=a9dric_Le_Goater?= Message-ID: <64551e66-e867-037e-bf2e-efa22ebdd324@kaod.org> Date: Thu, 6 Aug 2020 19:55:29 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <159673298011.766512.17389427967409788911.stgit@bahia.lan> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [37.59.142.99] X-ClientProxiedBy: DAG6EX2.mxp5.local (172.16.2.52) To DAG4EX1.mxp5.local (172.16.2.31) X-Ovh-Tracer-GUID: 6c7ffe20-f65f-40cd-82be-8b15857f9c28 X-Ovh-Tracer-Id: 4904982945362643875 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduiedrkedtgdduvdduucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuqfggjfdpvefjgfevmfevgfenuceurghilhhouhhtmecuhedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhepuffvfhfhkffffgggjggtgfhisehtjeertddtfeejnecuhfhrohhmpeevrogurhhitggpnfgvpgfiohgrthgvrhcuoegtlhhgsehkrghougdrohhrgheqnecuggftrfgrthhtvghrnhepgedvieejfedvhfduhfffueevheeludffhfdvkeehleegtddttdfhieegveeghfffnecukfhppedtrddtrddtrddtpdefjedrheelrddugedvrdelleenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhhouggvpehsmhhtphdqohhuthdphhgvlhhopehmgihplhgrnhehrdhmrghilhdrohhvhhdrnhgvthdpihhnvghtpedtrddtrddtrddtpdhmrghilhhfrhhomheptghlgheskhgrohgurdhorhhgpdhrtghpthhtohepghhrohhugheskhgrohgurdhorhhg Received-SPF: pass client-ip=79.137.123.220; envelope-from=clg@kaod.org; helo=smtpout1.mo804.mail-out.ovh.net X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/06 13:55:31 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Daniel Henrique Barboza , qemu-ppc@nongnu.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 8/6/20 6:56 PM, Greg Kurz wrote: > Calls to the KVM XIVE device are guarded by kvm_irqchip_in_kernel(). This > ensures that QEMU won't try to use the device if KVM is disabled or if > an in-kernel irqchip isn't required. > > When using ic-mode=dual with the pseries machine, we have two possible > interrupt controllers: XIVE and XICS. The kvm_irqchip_in_kernel() helper > will return true as soon as any of the KVM device is created. It might > lure QEMU to think that the other one is also around, while it is not. > This is exactly what happens with ic-mode=dual at machine init when > claiming IRQ numbers, which must be done on all possible IRQ backends, > eg. RTAS event sources or the PHB0 LSI table : only the KVM XICS device > is active but we end up calling kvmppc_xive_source_reset_one() anyway, > which fails. This doesn't cause any trouble because of another bug : > kvmppc_xive_source_reset_one() lacks an error_setg() and callers don't > see the failure. > > Most of the other kvmppc_xive_* functions have similar xive->fd > checks to filter out the case when KVM XIVE isn't active. It > might look safer to have idempotent functions but it doesn't > really help to understand what's going on when debugging. > > Since we already have all the kvm_irqchip_in_kernel() in place, > also have the callers to check xive->fd as well before calling > KVM XIVE specific code. This is straight-forward for the spapr > specific XIVE code. Some more care is needed for the platform > agnostic XIVE code since it cannot access xive->fd directly. > Introduce new in_kernel() methods in some base XIVE classes > for this purpose and implement them only in spapr. > > In all cases, we still need to call kvm_irqchip_in_kernel() so that > compilers can optimize the kvmppc_xive_* calls away when CONFIG_KVM > isn't defined, thus avoiding the need for stubs. > > Signed-off-by: Greg Kurz > --- > v2: Introduce in_kernel() abstract methods in the base XIVE classes > --- > hw/intc/spapr_xive.c | 53 ++++++++++++++++++++++++++++++++++++------------- > hw/intc/xive.c | 28 +++++++++++++++++++------- > include/hw/ppc/xive.h | 2 ++ > 3 files changed, 62 insertions(+), 21 deletions(-) > > diff --git a/hw/intc/spapr_xive.c b/hw/intc/spapr_xive.c > index 89c8cd96670b..cd001c580e89 100644 > --- a/hw/intc/spapr_xive.c > +++ b/hw/intc/spapr_xive.c > @@ -148,12 +148,19 @@ static void spapr_xive_end_pic_print_info(SpaprXive *xive, XiveEND *end, > xive_end_queue_pic_print_info(end, 6, mon); > } > > +/* > + * kvm_irqchip_in_kernel() will cause the compiler to turn this > + * info a nop if CONFIG_KVM isn't defined. > + */ > +#define spapr_xive_in_kernel(xive) \ > + (kvm_irqchip_in_kernel() && (xive)->fd != -1) > + This looks ok. SpaprXive is the userspace frontend device of the KVM XIVE native device in the hypervisor. > void spapr_xive_pic_print_info(SpaprXive *xive, Monitor *mon) > { > XiveSource *xsrc = &xive->source; > int i; > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_synchronize_state(xive, &local_err); > @@ -507,8 +514,10 @@ static const VMStateDescription vmstate_spapr_xive_eas = { > > static int vmstate_spapr_xive_pre_save(void *opaque) > { > - if (kvm_irqchip_in_kernel()) { > - return kvmppc_xive_pre_save(SPAPR_XIVE(opaque)); > + SpaprXive *xive = SPAPR_XIVE(opaque); > + > + if (spapr_xive_in_kernel(xive)) { > + return kvmppc_xive_pre_save(xive); > } > > return 0; > @@ -520,8 +529,10 @@ static int vmstate_spapr_xive_pre_save(void *opaque) > */ > static int spapr_xive_post_load(SpaprInterruptController *intc, int version_id) > { > - if (kvm_irqchip_in_kernel()) { > - return kvmppc_xive_post_load(SPAPR_XIVE(intc), version_id); > + SpaprXive *xive = SPAPR_XIVE(intc); > + > + if (spapr_xive_in_kernel(xive)) { > + return kvmppc_xive_post_load(xive, version_id); > } > > return 0; > @@ -564,7 +575,7 @@ static int spapr_xive_claim_irq(SpaprInterruptController *intc, int lisn, > xive_source_irq_set_lsi(xsrc, lisn); > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > return kvmppc_xive_source_reset_one(xsrc, lisn, errp); > } > > @@ -641,7 +652,7 @@ static void spapr_xive_set_irq(SpaprInterruptController *intc, int irq, int val) > { > SpaprXive *xive = SPAPR_XIVE(intc); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > kvmppc_xive_source_set_irq(&xive->source, irq, val); > } else { > xive_source_set_irq(&xive->source, irq, val); > @@ -749,11 +760,21 @@ static void spapr_xive_deactivate(SpaprInterruptController *intc) > > spapr_xive_mmio_set_enabled(xive, false); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > kvmppc_xive_disconnect(intc); > } > } > > +static bool spapr_xive_in_kernel_xptr(const XivePresenter *xptr) > +{ > + return spapr_xive_in_kernel(SPAPR_XIVE(xptr)); > +} This is mostly OK, a XivePresenter is a part of the XiveRouter. > +static bool spapr_xive_in_kernel_xn(const XiveNotifier *xn) > +{ > + return spapr_xive_in_kernel(SPAPR_XIVE(xn)); > +} This is weird. we have other XiveNotifiers which have no relation with a kernel backend. > static void spapr_xive_class_init(ObjectClass *klass, void *data) > { > DeviceClass *dc = DEVICE_CLASS(klass); > @@ -761,6 +782,7 @@ static void spapr_xive_class_init(ObjectClass *klass, void *data) > SpaprInterruptControllerClass *sicc = SPAPR_INTC_CLASS(klass); > XivePresenterClass *xpc = XIVE_PRESENTER_CLASS(klass); > SpaprXiveClass *sxc = SPAPR_XIVE_CLASS(klass); > + XiveNotifierClass *xnc = XIVE_NOTIFIER_CLASS(klass); > > dc->desc = "sPAPR XIVE Interrupt Controller"; > device_class_set_props(dc, spapr_xive_properties); > @@ -788,6 +810,9 @@ static void spapr_xive_class_init(ObjectClass *klass, void *data) > sicc->post_load = spapr_xive_post_load; > > xpc->match_nvt = spapr_xive_match_nvt; > + xpc->in_kernel = spapr_xive_in_kernel_xptr; > + > + xnc->in_kernel = spapr_xive_in_kernel_xn; > } > > static const TypeInfo spapr_xive_info = { > @@ -1058,7 +1083,7 @@ static target_ulong h_int_set_source_config(PowerPCCPU *cpu, > new_eas.w = xive_set_field64(EAS_END_DATA, new_eas.w, eisn); > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_set_source_config(xive, lisn, &new_eas, &local_err); > @@ -1379,7 +1404,7 @@ static target_ulong h_int_set_queue_config(PowerPCCPU *cpu, > */ > > out: > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_set_queue_config(xive, end_blk, end_idx, &end, &local_err); > @@ -1480,7 +1505,7 @@ static target_ulong h_int_get_queue_config(PowerPCCPU *cpu, > args[2] = 0; > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_get_queue_config(xive, end_blk, end_idx, end, &local_err); > @@ -1642,7 +1667,7 @@ static target_ulong h_int_esb(PowerPCCPU *cpu, > return H_P3; > } > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > args[0] = kvmppc_xive_esb_rw(xsrc, lisn, offset, data, > flags & SPAPR_XIVE_ESB_STORE); > } else { > @@ -1717,7 +1742,7 @@ static target_ulong h_int_sync(PowerPCCPU *cpu, > * under KVM > */ > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_sync_source(xive, lisn, &local_err); > @@ -1761,7 +1786,7 @@ static target_ulong h_int_reset(PowerPCCPU *cpu, > > device_legacy_reset(DEVICE(xive)); > > - if (kvm_irqchip_in_kernel()) { > + if (spapr_xive_in_kernel(xive)) { > Error *local_err = NULL; > > kvmppc_xive_reset(xive, &local_err); > diff --git a/hw/intc/xive.c b/hw/intc/xive.c > index 9b55e0356c62..27d27fdc9ee4 100644 > --- a/hw/intc/xive.c > +++ b/hw/intc/xive.c > @@ -592,6 +592,17 @@ static const char * const xive_tctx_ring_names[] = { > "USER", "OS", "POOL", "PHYS", > }; > > +/* > + * kvm_irqchip_in_kernel() will cause the compiler to turn this > + * info a nop if CONFIG_KVM isn't defined. > + */ > +#define xive_in_kernel(xptr) \ > + (kvm_irqchip_in_kernel() && \ > + ({ \ > + XivePresenterClass *xpc = XIVE_PRESENTER_GET_CLASS(xptr); \ > + xpc->in_kernel ? xpc->in_kernel(xptr) : false; \ > + })) > + > > void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon) > { > int cpu_index; > @@ -606,7 +617,7 @@ void xive_tctx_pic_print_info(XiveTCTX *tctx, Monitor *mon) > > cpu_index = tctx->cs ? tctx->cs->cpu_index : -1; > > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > Error *local_err = NULL; > > kvmppc_xive_cpu_synchronize_state(tctx, &local_err); > @@ -671,7 +682,7 @@ static void xive_tctx_realize(DeviceState *dev, Error **errp) > } > > /* Connect the presenter to the VCPU (required for CPU hotplug) */ > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > kvmppc_xive_cpu_connect(tctx, &local_err); > if (local_err) { > error_propagate(errp, local_err); > @@ -682,10 +693,11 @@ static void xive_tctx_realize(DeviceState *dev, Error **errp) > > static int vmstate_xive_tctx_pre_save(void *opaque) > { > + XiveTCTX *tctx = XIVE_TCTX(opaque); > Error *local_err = NULL; > > - if (kvm_irqchip_in_kernel()) { > - kvmppc_xive_cpu_get_state(XIVE_TCTX(opaque), &local_err); > + if (xive_in_kernel(tctx->xptr)) { > + kvmppc_xive_cpu_get_state(tctx, &local_err); > if (local_err) { > error_report_err(local_err); > return -1; > @@ -697,14 +709,15 @@ static int vmstate_xive_tctx_pre_save(void *opaque) > > static int vmstate_xive_tctx_post_load(void *opaque, int version_id) > { > + XiveTCTX *tctx = XIVE_TCTX(opaque); > Error *local_err = NULL; > > - if (kvm_irqchip_in_kernel()) { > + if (xive_in_kernel(tctx->xptr)) { > /* > * Required for hotplugged CPU, for which the state comes > * after all states of the machine. > */ > - kvmppc_xive_cpu_set_state(XIVE_TCTX(opaque), &local_err); > + kvmppc_xive_cpu_set_state(tctx, &local_err); > if (local_err) { > error_report_err(local_err); > return -1; > @@ -1128,6 +1141,7 @@ static void xive_source_reset(void *dev) > static void xive_source_realize(DeviceState *dev, Error **errp) > { > XiveSource *xsrc = XIVE_SOURCE(dev); > + XiveNotifierClass *xnc = XIVE_NOTIFIER_GET_CLASS(xsrc->xive); > > assert(xsrc->xive); > > @@ -1147,7 +1161,7 @@ static void xive_source_realize(DeviceState *dev, Error **errp) > xsrc->status = g_malloc0(xsrc->nr_irqs); > xsrc->lsi_map = bitmap_new(xsrc->nr_irqs); > > - if (!kvm_irqchip_in_kernel()) { > + if (!xnc->in_kernel || !xnc->in_kernel(xsrc->xive)) { > memory_region_init_io(&xsrc->esb_mmio, OBJECT(xsrc), > &xive_source_esb_ops, xsrc, "xive.esb", > (1ull << xsrc->esb_shift) * xsrc->nr_irqs); > diff --git a/include/hw/ppc/xive.h b/include/hw/ppc/xive.h > index 705cf48176fc..aa46e3fcf512 100644 > --- a/include/hw/ppc/xive.h > +++ b/include/hw/ppc/xive.h > @@ -161,6 +161,7 @@ typedef struct XiveNotifier XiveNotifier; > typedef struct XiveNotifierClass { > InterfaceClass parent; > void (*notify)(XiveNotifier *xn, uint32_t lisn); > + bool (*in_kernel)(const XiveNotifier *xn); > } XiveNotifierClass; > > /* > @@ -396,6 +397,7 @@ typedef struct XivePresenterClass { > uint8_t nvt_blk, uint32_t nvt_idx, > bool cam_ignore, uint8_t priority, > uint32_t logic_serv, XiveTCTXMatch *match); > + bool (*in_kernel)(const XivePresenter *xptr); > } XivePresenterClass; > > int xive_presenter_tctx_match(XivePresenter *xptr, XiveTCTX *tctx, > > It seems redundant. Can we introduce a new XiveBackend QOM interface which would implement an in_kernel() handler ? and XiveRouter would inherit from it. C.