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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT 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 6D7D8C04AB1 for ; Mon, 13 May 2019 08:59:57 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 328942146F for ; Mon, 13 May 2019 08:59:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 328942146F 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 ([127.0.0.1]:53469 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQ6oO-0006sz-BM for qemu-devel@archiver.kernel.org; Mon, 13 May 2019 04:59:56 -0400 Received: from eggs.gnu.org ([209.51.188.92]:33325) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQ6nA-0006PK-6H for qemu-devel@nongnu.org; Mon, 13 May 2019 04:58:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hQ6YW-00044d-Nd for qemu-devel@nongnu.org; Mon, 13 May 2019 04:43:34 -0400 Received: from 10.mo69.mail-out.ovh.net ([46.105.73.241]:44265) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hQ6YW-000448-Fq for qemu-devel@nongnu.org; Mon, 13 May 2019 04:43:32 -0400 Received: from player778.ha.ovh.net (unknown [10.109.143.72]) by mo69.mail-out.ovh.net (Postfix) with ESMTP id 1F3F055227 for ; Mon, 13 May 2019 10:43:31 +0200 (CEST) Received: from kaod.org (lfbn-1-10649-41.w90-89.abo.wanadoo.fr [90.89.235.41]) (Authenticated sender: clg@kaod.org) by player778.ha.ovh.net (Postfix) with ESMTPSA id 668C859C3DDA; Mon, 13 May 2019 08:43:23 +0000 (UTC) From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= To: David Gibson Date: Mon, 13 May 2019 10:42:36 +0200 Message-Id: <20190513084245.25755-6-clg@kaod.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190513084245.25755-1-clg@kaod.org> References: <20190513084245.25755-1-clg@kaod.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Ovh-Tracer-Id: 3329004550225431526 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduuddrleeggddtiecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemucehtddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 46.105.73.241 Subject: [Qemu-devel] [PATCH v4 05/14] spapr/xive: introduce a VM state change handler X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= , qemu-ppc@nongnu.org, qemu-devel@nongnu.org, Greg Kurz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This handler is in charge of stabilizing the flow of event notifications in the XIVE controller before migrating a guest. This is a requirement before transferring the guest EQ pages to a destination. When the VM is stopped, the handler sets the source PQs to PENDING to stop the flow of events and to possibly catch a triggered interrupt occuring while the VM is stopped. Their previous state is saved. The XIVE controller is then synced through KVM to flush any in-flight event notification and to stabilize the EQs. At this stage, the EQ pages are marked dirty to make sure the EQ pages are transferred if a migration sequence is in progress. The previous configuration of the sources is restored when the VM resumes, after a migration or a stop. If an interrupt was queued while the VM was stopped, the handler simply generates the missing trigger. Signed-off-by: C=C3=A9dric Le Goater Reviewed-by: David Gibson --- include/hw/ppc/spapr_xive.h | 1 + hw/intc/spapr_xive_kvm.c | 96 ++++++++++++++++++++++++++++++++++++- 2 files changed, 96 insertions(+), 1 deletion(-) diff --git a/include/hw/ppc/spapr_xive.h b/include/hw/ppc/spapr_xive.h index 7e49badd8c9a..734662c12a10 100644 --- a/include/hw/ppc/spapr_xive.h +++ b/include/hw/ppc/spapr_xive.h @@ -42,6 +42,7 @@ typedef struct SpaprXive { /* KVM support */ int fd; void *tm_mmap; + VMChangeStateEntry *change; } SpaprXive; =20 /* diff --git a/hw/intc/spapr_xive_kvm.c b/hw/intc/spapr_xive_kvm.c index 8dd4f96e0b97..735577a6f816 100644 --- a/hw/intc/spapr_xive_kvm.c +++ b/hw/intc/spapr_xive_kvm.c @@ -433,9 +433,100 @@ static void kvmppc_xive_get_queues(SpaprXive *xive,= Error **errp) } } =20 +/* + * The primary goal of the XIVE VM change handler is to mark the EQ + * pages dirty when all XIVE event notifications have stopped. + * + * Whenever the VM is stopped, the VM change handler sets the source + * PQs to PENDING to stop the flow of events and to possibly catch a + * triggered interrupt occuring while the VM is stopped. The previous + * state is saved in anticipation of a migration. The XIVE controller + * is then synced through KVM to flush any in-flight event + * notification and stabilize the EQs. + * + * At this stage, we can mark the EQ page dirty and let a migration + * sequence transfer the EQ pages to the destination, which is done + * just after the stop state. + * + * The previous configuration of the sources is restored when the VM + * runs again. If an interrupt was queued while the VM was stopped, + * simply generate a trigger. + */ +static void kvmppc_xive_change_state_handler(void *opaque, int running, + RunState state) +{ + SpaprXive *xive =3D opaque; + XiveSource *xsrc =3D &xive->source; + Error *local_err =3D NULL; + int i; + + /* + * Restore the sources to their initial state. This is called when + * the VM resumes after a stop or a migration. + */ + if (running) { + for (i =3D 0; i < xsrc->nr_irqs; i++) { + uint8_t pq =3D xive_source_esb_get(xsrc, i); + uint8_t old_pq; + + old_pq =3D xive_esb_read(xsrc, i, XIVE_ESB_SET_PQ_00 + (pq <= < 8)); + + /* + * An interrupt was queued while the VM was stopped, + * generate a trigger. + */ + if (pq =3D=3D XIVE_ESB_RESET && old_pq =3D=3D XIVE_ESB_QUEUE= D) { + xive_esb_trigger(xsrc, i); + } + } + + return; + } + + /* + * Mask the sources, to stop the flow of event notifications, and + * save the PQs locally in the XiveSource object. The XiveSource + * state will be collected later on by its vmstate handler if a + * migration is in progress. + */ + for (i =3D 0; i < xsrc->nr_irqs; i++) { + uint8_t pq =3D xive_esb_read(xsrc, i, XIVE_ESB_GET); + + /* + * PQ is set to PENDING to possibly catch a triggered + * interrupt occuring while the VM is stopped (hotplug event + * for instance) . + */ + if (pq !=3D XIVE_ESB_OFF) { + pq =3D xive_esb_read(xsrc, i, XIVE_ESB_SET_PQ_10); + } + xive_source_esb_set(xsrc, i, pq); + } + + /* + * Sync the XIVE controller in KVM, to flush in-flight event + * notification that should be enqueued in the EQs and mark the + * XIVE EQ pages dirty to collect all updates. + */ + kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_CTRL, + KVM_DEV_XIVE_EQ_SYNC, NULL, true, &local_err); + if (local_err) { + error_report_err(local_err); + return; + } +} + void kvmppc_xive_synchronize_state(SpaprXive *xive, Error **errp) { - kvmppc_xive_source_get_state(&xive->source); + /* + * When the VM is stopped, the sources are masked and the previous + * state is saved in anticipation of a migration. We should not + * synchronize the source state in that case else we will override + * the saved state. + */ + if (runstate_is_running()) { + kvmppc_xive_source_get_state(&xive->source); + } =20 /* EAT: there is no extra state to query from KVM */ =20 @@ -515,6 +606,9 @@ void kvmppc_xive_connect(SpaprXive *xive, Error **err= p) "xive.tima", tima_len, xive->tm_mm= ap); sysbus_init_mmio(SYS_BUS_DEVICE(xive), &xive->tm_mmio); =20 + xive->change =3D qemu_add_vm_change_state_handler( + kvmppc_xive_change_state_handler, xive); + kvm_kernel_irqchip =3D true; kvm_msi_via_irqfd_allowed =3D true; kvm_gsi_direct_mapping =3D true; --=20 2.20.1