xenbus: frontend resume cleanup

Only create the delayed resume workqueue if we are running in the same domain
as xenstored and issue a warning if the workqueue creation fails.

Move the work initialization to the device probe so it is done only once.

Signed-off-by: Aurelien Chartier <aurelien.chartier@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>

1 files changed, 16 insertions, 3 deletions

diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index 6ed8a9df4472..34b20bfa4e8c 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -115,7 +115,6 @@ static int xenbus_frontend_dev_resume(struct device *dev)
                         return -EFAULT;
                 }
 
-                INIT_WORK(&xdev->work, xenbus_frontend_delayed_resume);
                 queue_work(xenbus_frontend_wq, &xdev->work);
 
                 return 0;
@@ -124,6 +123,16 @@ static int xenbus_frontend_dev_resume(struct device *dev)
         return xenbus_dev_resume(dev);
 }
 
+static int xenbus_frontend_dev_probe(struct device *dev)
+{
+        if (xen_store_domain_type == XS_LOCAL) {
+                struct xenbus_device *xdev = to_xenbus_device(dev);
+                INIT_WORK(&xdev->work, xenbus_frontend_delayed_resume);
+        }
+
+        return xenbus_dev_probe(dev);
+}
+
 static const struct dev_pm_ops xenbus_pm_ops = {
         .suspend        = xenbus_dev_suspend,
         .resume         = xenbus_frontend_dev_resume,
@@ -142,7 +151,7 @@ static struct xen_bus_type xenbus_frontend = {
                 .name           = "xen",
                 .match          = xenbus_match,
                 .uevent         = xenbus_uevent_frontend,
-                .probe          = xenbus_dev_probe,
+                .probe          = xenbus_frontend_dev_probe,
                 .remove         = xenbus_dev_remove,
                 .shutdown       = xenbus_dev_shutdown,
                 .dev_attrs      = xenbus_dev_attrs,
@@ -474,7 +483,11 @@ static int __init xenbus_probe_frontend_init(void)
 
         register_xenstore_notifier(&xenstore_notifier);
 
-        xenbus_frontend_wq = create_workqueue("xenbus_frontend");
+        if (xen_store_domain_type == XS_LOCAL) {
+                xenbus_frontend_wq = create_workqueue("xenbus_frontend");
+                if (!xenbus_frontend_wq)
+                        pr_warn("create xenbus frontend workqueue failed, S3 resume is likely to fail\n");
+        }
 
         return 0;
 }