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author | Paul Durrant <paul.durrant@citrix.com> | 2019-04-08 16:16:15 +0100 |
---|---|---|
committer | Anthony PERARD <anthony.perard@citrix.com> | 2019-06-24 10:42:29 +0100 |
commit | c0b336ea19a93801ee2333be525d0473d28a10f8 (patch) | |
tree | d74b1d1fda827ae9e221539e82b07330834a2594 /hw | |
parent | 5feeb718d7914c3c921cc811a5844488a5644ea6 (diff) | |
download | qemu-c0b336ea19a93801ee2333be525d0473d28a10f8.zip qemu-c0b336ea19a93801ee2333be525d0473d28a10f8.tar.gz qemu-c0b336ea19a93801ee2333be525d0473d28a10f8.tar.bz2 |
xen-bus: use a separate fd for each event channel
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 <paul.durrant@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Message-Id: <20190408151617.13025-2-paul.durrant@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Diffstat (limited to 'hw')
-rw-r--r-- | hw/xen/xen-bus.c | 79 |
1 files changed, 40 insertions, 39 deletions
diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c index a4416d0..43a90ca 100644 --- a/hw/xen/xen-bus.c +++ b/hw/xen/xen-bus.c @@ -924,19 +924,22 @@ 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); } } @@ -948,24 +951,39 @@ 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, @@ -977,7 +995,7 @@ 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"); } } @@ -991,12 +1009,15 @@ 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); } @@ -1005,6 +1026,7 @@ 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; @@ -1021,15 +1043,14 @@ 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; @@ -1046,16 +1067,6 @@ 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); @@ -1096,16 +1107,6 @@ 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); |