isdn/capi: make kcapi use a separate workqueue

flush_scheduled_work() is deprecated and will be removed.  Because
kcapi uses fire-and-forget type works, it's impossible to flush each
work explicitly.  Create and use a dedicated workqueue instead.

Please note that with recent workqueue changes, each workqueue doesn't
reserve a lot of resources and using it as a flush domain is fine.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jan Kiszka <jan.kiszka@web.de>

1 files changed, 18 insertions, 8 deletions

diff --git a/drivers/isdn/capi/kcapi.c b/drivers/isdn/capi/kcapi.c
index 3acf94cc5acd..2b33b2627fce 100644
--- a/drivers/isdn/capi/kcapi.c
+++ b/drivers/isdn/capi/kcapi.c
@@ -38,6 +38,7 @@
 #include <linux/rcupdate.h>
 
 static int showcapimsgs = 0;
+static struct workqueue_struct *kcapi_wq;
 
 MODULE_DESCRIPTION("CAPI4Linux: kernel CAPI layer");
 MODULE_AUTHOR("Carsten Paeth");
@@ -291,7 +292,7 @@ static int notify_push(unsigned int event_type, u32 controller)
         event->type = event_type;
         event->controller = controller;
 
-        schedule_work(&event->work);
+        queue_work(kcapi_wq, &event->work);
         return 0;
 }
 
@@ -408,7 +409,7 @@ void capi_ctr_handle_message(struct capi_ctr *ctr, u16 appl,
                 goto error;
         }
         skb_queue_tail(&ap->recv_queue, skb);
-        schedule_work(&ap->recv_work);
+        queue_work(kcapi_wq, &ap->recv_work);
         rcu_read_unlock();
 
         return;
@@ -743,7 +744,7 @@ u16 capi20_release(struct capi20_appl *ap)
 
         mutex_unlock(&capi_controller_lock);
 
-        flush_scheduled_work();
+        flush_workqueue(kcapi_wq);
         skb_queue_purge(&ap->recv_queue);
 
         if (showcapimsgs & 1) {
@@ -1285,21 +1286,30 @@ static int __init kcapi_init(void)
 {
         int err;
 
+        kcapi_wq = alloc_workqueue("kcapi", 0, 0);
+        if (!kcapi_wq)
+                return -ENOMEM;
+
         register_capictr_notifier(&capictr_nb);
 
         err = cdebug_init();
-        if (!err)
-                kcapi_proc_init();
-        return err;
+        if (err) {
+                unregister_capictr_notifier(&capictr_nb);
+                destroy_workqueue(kcapi_wq);
+                return err;
+        }
+
+        kcapi_proc_init();
+        return 0;
 }
 
 static void __exit kcapi_exit(void)
 {
         kcapi_proc_exit();
 
-        /* make sure all notifiers are finished */
-        flush_scheduled_work();
+        unregister_capictr_notifier(&capictr_nb);
         cdebug_exit();
+        destroy_workqueue(kcapi_wq);
 }
 
 module_init(kcapi_init);