From: Prarit Bhargava <prarit@redhat.com>
Date: Fri, 28 May 2010 15:04:02 -0400
Subject: [misc] compat.h cleanup: add cancel_delayed_work_sync
Message-id: <4BFFDB62.6030301@redhat.com>
Patchwork-id: 25895
O-Subject: Re: [RHEL5 PATCH 26/27] compat.h cleanup:
	add	cancel_delayed_work_sync()
Bugzilla: 546740
RH-Acked-by: Oleg Nesterov <oleg@redhat.com>

New "simple" cancel_delayed_work_sync() implementation.

This will be deprecated by Oleg's implementation, but for now maintain
consistency with previous implementations of the function.

Signed-off-by: Jarod Wilson <jarod@redhat.com>

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index bf62923..7ea17c8 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -19,11 +19,19 @@ struct work_struct {
 	void *wq_data;
 	struct timer_list timer;
 };
+typedef void (*work_func_t)(void *data);
 
 struct execute_work {
 	struct work_struct work;
 };
 
+struct delayed_work {
+	struct work_struct work;
+#if 0 /* not used in RHEL5 */
+	struct timer_list timer;
+#endif
+};
+
 #define __WORK_INITIALIZER(n, f, d) {				\
         .entry	= { &(n).entry, &(n).entry },			\
 	.func = (f),						\
@@ -54,6 +62,9 @@ struct execute_work {
 		init_timer(&(_work)->timer);			\
 	} while (0)
 
+#define INIT_DELAYED_WORK(_work, _func) \
+	INIT_WORK(&(_work)->work, _func, &(_work)->work) /* for RHEL5 */
+
 extern struct workqueue_struct *__create_workqueue(const char *name,
 						    int singlethread);
 #define create_workqueue(name) __create_workqueue((name), 0)
@@ -103,4 +114,18 @@ static inline int delayed_work_pending(struct work_struct *work)
 	return test_bit(0, &work->pending);
 }
 
+/**
+ * cancel_delayed_work_sync - reliably kill off a delayed work.
+ * @dwork: the delayed work struct
+ */
+
+static inline int cancel_delayed_work_sync(struct delayed_work *dwork)
+{
+	int ret;
+
+	ret = cancel_delayed_work(&dwork->work);
+	if (!ret)
+		flush_scheduled_work();
+	return ret;
+}
 #endif