From patchwork Thu Mar 21 14:49:04 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 10863735 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0B98E922 for ; Thu, 21 Mar 2019 14:54:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E40452A150 for ; Thu, 21 Mar 2019 14:54:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D7A032A1E1; Thu, 21 Mar 2019 14:54:57 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=ham version=3.3.1 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.wl.linuxfoundation.org (Postfix) with ESMTPS id 474DC2A1D7 for ; Thu, 21 Mar 2019 14:54:57 +0000 (UTC) Received: from localhost ([127.0.0.1]:38882 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h6z5s-0008B0-EG for patchwork-qemu-devel@patchwork.kernel.org; Thu, 21 Mar 2019 10:54:56 -0400 Received: from eggs.gnu.org ([209.51.188.92]:43966) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1h6z1C-0003VR-T0 for qemu-devel@nongnu.org; Thu, 21 Mar 2019 10:50:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1h6z1A-0000Wy-Gd for qemu-devel@nongnu.org; Thu, 21 Mar 2019 10:50:06 -0400 Received: from 14.mo4.mail-out.ovh.net ([46.105.40.29]:33531) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1h6z17-0000KE-1F for qemu-devel@nongnu.org; Thu, 21 Mar 2019 10:50:01 -0400 Received: from player788.ha.ovh.net (unknown [10.109.143.220]) by mo4.mail-out.ovh.net (Postfix) with ESMTP id 5CD8C1DFCBB for ; Thu, 21 Mar 2019 15:49:56 +0100 (CET) Received: from kaod.org (deibp9eh1--blueice1n0.emea.ibm.com [195.212.29.162]) (Authenticated sender: clg@kaod.org) by player788.ha.ovh.net (Postfix) with ESMTPSA id 8C1C23E6B4C8; Thu, 21 Mar 2019 14:49:50 +0000 (UTC) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: David Gibson Date: Thu, 21 Mar 2019 15:49:04 +0100 Message-Id: <20190321144914.19934-6-clg@kaod.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190321144914.19934-1-clg@kaod.org> References: <20190321144914.19934-1-clg@kaod.org> MIME-Version: 1.0 X-Ovh-Tracer-Id: 11859103721785428966 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgedutddrieelgdehgecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemucehtddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 46.105.40.29 Subject: [Qemu-devel] [PATCH v3 05/15] 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_Le_Goater?= , qemu-ppc@nongnu.org, Greg Kurz , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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: Cédric Le Goater Reviewed-by: David Gibson --- Changes since v2: - merged in handling of pending interrupts while the VM is stopped. 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; /* diff --git a/hw/intc/spapr_xive_kvm.c b/hw/intc/spapr_xive_kvm.c index 2e46661cb3ad..a011d415ee51 100644 --- a/hw/intc/spapr_xive_kvm.c +++ b/hw/intc/spapr_xive_kvm.c @@ -431,9 +431,100 @@ static void kvmppc_xive_get_queues(SpaprXive *xive, Error **errp) } } +/* + * 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 = opaque; + XiveSource *xsrc = &xive->source; + Error *local_err = 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 = 0; i < xsrc->nr_irqs; i++) { + uint8_t pq = xive_source_esb_get(xsrc, i); + uint8_t old_pq; + + old_pq = 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 == XIVE_ESB_RESET && old_pq == XIVE_ESB_QUEUED) { + 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 = 0; i < xsrc->nr_irqs; i++) { + uint8_t pq = 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 != XIVE_ESB_OFF) { + pq = 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); + } /* EAT: there is no extra state to query from KVM */ @@ -513,6 +604,9 @@ void kvmppc_xive_connect(SpaprXive *xive, Error **errp) "xive.tima", tima_len, xive->tm_mmap); sysbus_init_mmio(SYS_BUS_DEVICE(xive), &xive->tm_mmio); + xive->change = qemu_add_vm_change_state_handler( + kvmppc_xive_change_state_handler, xive); + kvm_kernel_irqchip = true; kvm_msi_via_irqfd_allowed = true; kvm_gsi_direct_mapping = true;