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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,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 EFC3BC7618F for ; Tue, 16 Jul 2019 22:03:31 +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 BF1D52173B for ; Tue, 16 Jul 2019 22:03:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BF1D52173B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52590 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hnVXm-0002PB-TO for qemu-devel@archiver.kernel.org; Tue, 16 Jul 2019 18:03:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37885) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hnVXX-0001zm-By for qemu-devel@nongnu.org; Tue, 16 Jul 2019 18:03:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hnVXT-0001bC-11 for qemu-devel@nongnu.org; Tue, 16 Jul 2019 18:03:13 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38034) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hnVXQ-0001X8-LA for qemu-devel@nongnu.org; Tue, 16 Jul 2019 18:03:10 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B50A85C3; Tue, 16 Jul 2019 22:03:06 +0000 (UTC) Received: from x1.home (ovpn-116-35.phx2.redhat.com [10.3.116.35]) by smtp.corp.redhat.com (Postfix) with ESMTP id D05355D720; Tue, 16 Jul 2019 22:03:02 +0000 (UTC) Date: Tue, 16 Jul 2019 16:03:02 -0600 From: Alex Williamson To: Kirti Wankhede Message-ID: <20190716160302.09ef66e7@x1.home> In-Reply-To: <1562665760-26158-7-git-send-email-kwankhede@nvidia.com> References: <1562665760-26158-1-git-send-email-kwankhede@nvidia.com> <1562665760-26158-7-git-send-email-kwankhede@nvidia.com> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Tue, 16 Jul 2019 22:03:06 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v7 06/13] vfio: Add VM state change handler to know state of VM 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: Zhengxiao.zx@Alibaba-inc.com, kevin.tian@intel.com, yi.l.liu@intel.com, cjia@nvidia.com, eskultet@redhat.com, ziye.yang@intel.com, qemu-devel@nongnu.org, cohuck@redhat.com, shuangtai.tst@alibaba-inc.com, dgilbert@redhat.com, zhi.a.wang@intel.com, mlevitsk@redhat.com, pasic@linux.ibm.com, aik@ozlabs.ru, eauger@redhat.com, felipe@nutanix.com, jonathan.davies@nutanix.com, yan.y.zhao@intel.com, changpeng.liu@intel.com, Ken.Xue@amd.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 9 Jul 2019 15:19:13 +0530 Kirti Wankhede wrote: > VM state change handler gets called on change in VM's state. This is used to set > VFIO device state to _RUNNING. > VM state change handler, migration state change handler and log_sync listener > are called asynchronously, which sometimes lead to data corruption in migration > region. Initialised mutex that is used to serialize operations on migration data > region during saving state. > > Signed-off-by: Kirti Wankhede > Reviewed-by: Neo Jia > --- > hw/vfio/migration.c | 64 +++++++++++++++++++++++++++++++++++++++++++ > hw/vfio/trace-events | 2 ++ > include/hw/vfio/vfio-common.h | 4 +++ > 3 files changed, 70 insertions(+) > > diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > index a2cfbd5af2e1..c01f08b659d0 100644 > --- a/hw/vfio/migration.c > +++ b/hw/vfio/migration.c > @@ -78,6 +78,60 @@ err: > return ret; > } > > +static int vfio_migration_set_state(VFIODevice *vbasedev, uint32_t state) > +{ > + VFIOMigration *migration = vbasedev->migration; > + VFIORegion *region = &migration->region.buffer; > + uint32_t device_state; > + int ret = 0; > + > + device_state = (state & VFIO_DEVICE_STATE_MASK) | > + (vbasedev->device_state & ~VFIO_DEVICE_STATE_MASK); > + > + if ((device_state & VFIO_DEVICE_STATE_MASK) == VFIO_DEVICE_STATE_INVALID) { > + return -EINVAL; > + } > + > + ret = pwrite(vbasedev->fd, &device_state, sizeof(device_state), > + region->fd_offset + offsetof(struct vfio_device_migration_info, > + device_state)); > + if (ret < 0) { > + error_report("%s: Failed to set device state %d %s", > + vbasedev->name, ret, strerror(errno)); > + return ret; > + } > + > + vbasedev->device_state = device_state; Do we need to re-read device_state after error? We defined _SAVING | _RESUMING as STATE_INVALID, is that only for user writes, ie. the device can never transition to that state to indicate a fault? I was thinking that was one if its use cases. Thanks, Alex > + trace_vfio_migration_set_state(vbasedev->name, device_state); > + return 0; > +} > + > +static void vfio_vmstate_change(void *opaque, int running, RunState state) > +{ > + VFIODevice *vbasedev = opaque; > + > + if ((vbasedev->vm_running != running)) { > + int ret; > + uint32_t dev_state; > + > + if (running) { > + dev_state = VFIO_DEVICE_STATE_RUNNING; > + } else { > + dev_state = (vbasedev->device_state & VFIO_DEVICE_STATE_MASK) & > + ~VFIO_DEVICE_STATE_RUNNING; > + } > + > + ret = vfio_migration_set_state(vbasedev, dev_state); > + if (ret) { > + error_report("%s: Failed to set device state 0x%x", > + vbasedev->name, dev_state); > + } > + vbasedev->vm_running = running; > + trace_vfio_vmstate_change(vbasedev->name, running, RunState_str(state), > + dev_state); > + } > +} > + > static int vfio_migration_init(VFIODevice *vbasedev, > struct vfio_region_info *info) > { > @@ -93,6 +147,11 @@ static int vfio_migration_init(VFIODevice *vbasedev, > return ret; > } > > + qemu_mutex_init(&vbasedev->migration->lock); > + > + vbasedev->vm_state = qemu_add_vm_change_state_handler(vfio_vmstate_change, > + vbasedev); > + > return 0; > } > > @@ -135,11 +194,16 @@ void vfio_migration_finalize(VFIODevice *vbasedev) > return; > } > > + if (vbasedev->vm_state) { > + qemu_del_vm_change_state_handler(vbasedev->vm_state); > + } > + > if (vbasedev->migration_blocker) { > migrate_del_blocker(vbasedev->migration_blocker); > error_free(vbasedev->migration_blocker); > } > > + qemu_mutex_destroy(&vbasedev->migration->lock); > vfio_migration_region_exit(vbasedev); > g_free(vbasedev->migration); > } > diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events > index 191a726a1312..3d15bacd031a 100644 > --- a/hw/vfio/trace-events > +++ b/hw/vfio/trace-events > @@ -146,3 +146,5 @@ vfio_display_edid_write_error(void) "" > > # migration.c > vfio_migration_probe(char *name, uint32_t index) " (%s) Region %d" > +vfio_migration_set_state(char *name, uint32_t state) " (%s) state %d" > +vfio_vmstate_change(char *name, int running, const char *reason, uint32_t dev_state) " (%s) running %d reason %s device state %d" > diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h > index 152da3f8d6f3..f6c70db3a9c1 100644 > --- a/include/hw/vfio/vfio-common.h > +++ b/include/hw/vfio/vfio-common.h > @@ -29,6 +29,7 @@ > #ifdef CONFIG_LINUX > #include > #endif > +#include "sysemu/sysemu.h" > > #define VFIO_MSG_PREFIX "vfio %s: " > > @@ -124,6 +125,9 @@ typedef struct VFIODevice { > unsigned int flags; > VFIOMigration *migration; > Error *migration_blocker; > + uint32_t device_state; > + VMChangeStateEntry *vm_state; > + int vm_running; > } VFIODevice; > > struct VFIODeviceOps {