datapath: Add workqueue API to ovs compat workqueue.

Add work-queue api which are required for next commit.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>

diff --git a/datapath/linux/compat/include/linux/workqueue.h b/datapath/linux/compat/include/linux/workqueue.h
index cb48863..b2de545 100644 (file)
--- a/datapath/linux/compat/include/linux/workqueue.h
+++ b/datapath/linux/compat/include/linux/workqueue.h
@@ -68,5 +68,7 @@ int cancel_delayed_work_sync(struct delayed_work *dwork);
        } while (0)
 
 extern void flush_scheduled_work(void);
+extern void queue_work(struct work_struct *work);
+extern bool cancel_work_sync(struct work_struct *work);
 
 #endif

diff --git a/datapath/linux/compat/workqueue.c b/datapath/linux/compat/workqueue.c
index 9934f1a..cdb3615 100644 (file)
--- a/datapath/linux/compat/workqueue.c
+++ b/datapath/linux/compat/workqueue.c
@@ -29,20 +29,31 @@ static wait_queue_head_t more_work;
 static struct task_struct *workq_thread;
 static struct work_struct *current_work;
 
-static void queue_work(struct work_struct *work)
+static void add_work_to_ovs_wq(struct work_struct *work)
+{
+       list_add_tail(&work->entry, &workq);
+       wake_up(&more_work);
+}
+static void __queue_work(struct work_struct *work)
 {
        unsigned long flags;
 
        spin_lock_irqsave(&wq_lock, flags);
-       list_add_tail(&work->entry, &workq);
-       wake_up(&more_work);
+       add_work_to_ovs_wq(work);
        spin_unlock_irqrestore(&wq_lock, flags);
 }
 
+void queue_work(struct work_struct *work)
+{
+       if (test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work)))
+               return;
+       __queue_work(work);
+}
+
 static void _delayed_work_timer_fn(unsigned long __data)
 {
        struct delayed_work *dwork = (struct delayed_work *)__data;
-       queue_work(&dwork->work);
+       __queue_work(&dwork->work);
 }
 
 static void __queue_delayed_work(struct delayed_work *dwork,
@@ -67,7 +78,7 @@ int schedule_delayed_work(struct delayed_work *dwork, unsigned long delay)
                return 0;
 
        if (delay == 0)
-               queue_work(&dwork->work);
+               __queue_work(&dwork->work);
        else
                __queue_delayed_work(dwork, delay);
 
@@ -96,8 +107,7 @@ static void workqueue_barrier(struct work_struct *work)
        else {
                INIT_WORK(&barr.work, wq_barrier_func);
                init_completion(&barr.done);
-               list_add(&barr.work.entry, &workq);
-               wake_up(&more_work);
+               add_work_to_ovs_wq(&barr.work);
                need_barrier = true;
        }
        spin_unlock_irq(&wq_lock);
@@ -152,6 +162,11 @@ int cancel_delayed_work_sync(struct delayed_work *dwork)
        return __cancel_work_timer(&dwork->work, &dwork->timer);
 }
 
+bool cancel_work_sync(struct work_struct *work)
+{
+       return __cancel_work_timer(work, NULL);
+}
+
 static void run_workqueue(void)
 {
        spin_lock_irq(&wq_lock);