From patchwork Mon Apr 8 15:16:15 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Durrant X-Patchwork-Id: 1081159 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=citrix.com Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 44dDg95DYwz9sR1 for ; Tue, 9 Apr 2019 01:22:13 +1000 (AEST) Received: from localhost ([127.0.0.1]:54785 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hDW67-0005zH-OM for incoming@patchwork.ozlabs.org; Mon, 08 Apr 2019 11:22:11 -0400 Received: from eggs.gnu.org ([209.51.188.92]:40504) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hDW17-0002n9-5D for qemu-devel@nongnu.org; Mon, 08 Apr 2019 11:17:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hDW11-0001N0-Dy for qemu-devel@nongnu.org; Mon, 08 Apr 2019 11:16:57 -0400 Received: from smtp03.citrix.com ([162.221.156.55]:43196) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hDW0y-00010C-0U; Mon, 08 Apr 2019 11:16:53 -0400 X-IronPort-AV: E=Sophos;i="5.60,325,1549929600"; d="scan'208";a="83016890" From: Paul Durrant To: , , Date: Mon, 8 Apr 2019 16:16:15 +0100 Message-ID: <20190408151617.13025-2-paul.durrant@citrix.com> X-Mailer: git-send-email 2.20.1.2.gb21ebb6 In-Reply-To: <20190408151617.13025-1-paul.durrant@citrix.com> References: <20190408151617.13025-1-paul.durrant@citrix.com> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 162.221.156.55 Subject: [Qemu-devel] [PATCH 1/3] xen-bus: use a separate fd for each event channel 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: Anthony Perard , Paul Durrant , Stefano Stabellini Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" To better support use of IOThread-s it will be necessary to be able to set the AioContext for each XenEventChannel and hence it is necessary to open a separate handle to libxenevtchan for each channel. This patch stops using NotifierList for event channel callbacks, replacing that construct by a list of complete XenEventChannel structures. Each of these now has a xenevtchn_handle pointer in place of the single pointer previously held in the XenDevice structure. The individual handles are opened/closed in xen_device_bind/unbind_event_channel(), replacing the single open/close in xen_device_realize/unrealize(). NOTE: This patch does not add an AioContext parameter to xen_device_bind_event_channel(). That will be done in a subsequent patch. Signed-off-by: Paul Durrant Reviewed-by: Anthony PERARD --- Cc: Stefano Stabellini Cc: Anthony Perard --- hw/xen/xen-bus.c | 79 ++++++++++++++++++++-------------------- include/hw/xen/xen-bus.h | 6 +-- 2 files changed, 42 insertions(+), 43 deletions(-) diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c index 49a725e8c7..9e391492ac 100644 --- a/hw/xen/xen-bus.c +++ b/hw/xen/xen-bus.c @@ -923,19 +923,22 @@ done: } struct XenEventChannel { + QLIST_ENTRY(XenEventChannel) list; + xenevtchn_handle *xeh; evtchn_port_t local_port; XenEventHandler handler; void *opaque; - Notifier notifier; }; -static void event_notify(Notifier *n, void *data) +static void xen_device_event(void *opaque) { - XenEventChannel *channel = container_of(n, XenEventChannel, notifier); - unsigned long port = (unsigned long)data; + XenEventChannel *channel = opaque; + unsigned long port = xenevtchn_pending(channel->xeh); if (port == channel->local_port) { channel->handler(channel->opaque); + + xenevtchn_unmask(channel->xeh, port); } } @@ -947,24 +950,39 @@ XenEventChannel *xen_device_bind_event_channel(XenDevice *xendev, XenEventChannel *channel = g_new0(XenEventChannel, 1); xenevtchn_port_or_error_t local_port; - local_port = xenevtchn_bind_interdomain(xendev->xeh, + channel->xeh = xenevtchn_open(NULL, 0); + if (!channel->xeh) { + error_setg_errno(errp, errno, "failed xenevtchn_open"); + goto fail; + } + + local_port = xenevtchn_bind_interdomain(channel->xeh, xendev->frontend_id, port); if (local_port < 0) { error_setg_errno(errp, errno, "xenevtchn_bind_interdomain failed"); - - g_free(channel); - return NULL; + goto fail; } channel->local_port = local_port; channel->handler = handler; channel->opaque = opaque; - channel->notifier.notify = event_notify; - notifier_list_add(&xendev->event_notifiers, &channel->notifier); + qemu_set_fd_handler(xenevtchn_fd(channel->xeh), xen_device_event, NULL, + channel); + + QLIST_INSERT_HEAD(&xendev->event_channels, channel, list); return channel; + +fail: + if (channel->xeh) { + xenevtchn_close(channel->xeh); + } + + g_free(channel); + + return NULL; } void xen_device_notify_event_channel(XenDevice *xendev, @@ -976,7 +994,7 @@ void xen_device_notify_event_channel(XenDevice *xendev, return; } - if (xenevtchn_notify(xendev->xeh, channel->local_port) < 0) { + if (xenevtchn_notify(channel->xeh, channel->local_port) < 0) { error_setg_errno(errp, errno, "xenevtchn_notify failed"); } } @@ -990,12 +1008,15 @@ void xen_device_unbind_event_channel(XenDevice *xendev, return; } - notifier_remove(&channel->notifier); + QLIST_REMOVE(channel, list); - if (xenevtchn_unbind(xendev->xeh, channel->local_port) < 0) { + qemu_set_fd_handler(xenevtchn_fd(channel->xeh), NULL, NULL, NULL); + + if (xenevtchn_unbind(channel->xeh, channel->local_port) < 0) { error_setg_errno(errp, errno, "xenevtchn_unbind failed"); } + xenevtchn_close(channel->xeh); g_free(channel); } @@ -1004,6 +1025,7 @@ static void xen_device_unrealize(DeviceState *dev, Error **errp) XenDevice *xendev = XEN_DEVICE(dev); XenDeviceClass *xendev_class = XEN_DEVICE_GET_CLASS(xendev); const char *type = object_get_typename(OBJECT(xendev)); + XenEventChannel *channel, *next; if (!xendev->name) { return; @@ -1020,15 +1042,14 @@ static void xen_device_unrealize(DeviceState *dev, Error **errp) xendev_class->unrealize(xendev, errp); } + /* Make sure all event channels are cleaned up */ + QLIST_FOREACH_SAFE(channel, &xendev->event_channels, list, next) { + xen_device_unbind_event_channel(xendev, channel, NULL); + } + xen_device_frontend_destroy(xendev); xen_device_backend_destroy(xendev); - if (xendev->xeh) { - qemu_set_fd_handler(xenevtchn_fd(xendev->xeh), NULL, NULL, NULL); - xenevtchn_close(xendev->xeh); - xendev->xeh = NULL; - } - if (xendev->xgth) { xengnttab_close(xendev->xgth); xendev->xgth = NULL; @@ -1045,16 +1066,6 @@ static void xen_device_exit(Notifier *n, void *data) xen_device_unrealize(DEVICE(xendev), &error_abort); } -static void xen_device_event(void *opaque) -{ - XenDevice *xendev = opaque; - unsigned long port = xenevtchn_pending(xendev->xeh); - - notifier_list_notify(&xendev->event_notifiers, (void *)port); - - xenevtchn_unmask(xendev->xeh, port); -} - static void xen_device_realize(DeviceState *dev, Error **errp) { XenDevice *xendev = XEN_DEVICE(dev); @@ -1095,16 +1106,6 @@ static void xen_device_realize(DeviceState *dev, Error **errp) xendev->feature_grant_copy = (xengnttab_grant_copy(xendev->xgth, 0, NULL) == 0); - xendev->xeh = xenevtchn_open(NULL, 0); - if (!xendev->xeh) { - error_setg_errno(errp, errno, "failed xenevtchn_open"); - goto unrealize; - } - - notifier_list_init(&xendev->event_notifiers); - qemu_set_fd_handler(xenevtchn_fd(xendev->xeh), xen_device_event, NULL, - xendev); - xen_device_backend_create(xendev, &local_err); if (local_err) { error_propagate(errp, local_err); diff --git a/include/hw/xen/xen-bus.h b/include/hw/xen/xen-bus.h index 3183f10e3c..3315f0de20 100644 --- a/include/hw/xen/xen-bus.h +++ b/include/hw/xen/xen-bus.h @@ -15,6 +15,7 @@ typedef void (*XenWatchHandler)(void *opaque); typedef struct XenWatch XenWatch; +typedef struct XenEventChannel XenEventChannel; typedef struct XenDevice { DeviceState qdev; @@ -28,8 +29,7 @@ typedef struct XenDevice { XenWatch *backend_online_watch; xengnttab_handle *xgth; bool feature_grant_copy; - xenevtchn_handle *xeh; - NotifierList event_notifiers; + QLIST_HEAD(, XenEventChannel) event_channels; } XenDevice; typedef char *(*XenDeviceGetName)(XenDevice *xendev, Error **errp); @@ -119,8 +119,6 @@ void xen_device_copy_grant_refs(XenDevice *xendev, bool to_domain, XenDeviceGrantCopySegment segs[], unsigned int nr_segs, Error **errp); -typedef struct XenEventChannel XenEventChannel; - typedef void (*XenEventHandler)(void *opaque); XenEventChannel *xen_device_bind_event_channel(XenDevice *xendev,