1 files changed, 136 insertions, 30 deletions

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 9bca3539a1e..2a7b38d8701 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -8,15 +8,34 @@
 #include <linux/timer.h>
 #include <linux/linkage.h>
 #include <linux/bitops.h>
+#include <asm/atomic.h>
 
 struct workqueue_struct;
 
+struct work_struct;
+typedef void (*work_func_t)(struct work_struct *work);
+
+/*
+ * The first word is the work queue pointer and the flags rolled into
+ * one
+ */
+#define work_data_bits(work) ((unsigned long *)(&(work)->data))
+
 struct work_struct {
-	unsigned long pending;
+	atomic_long_t data;
+#define WORK_STRUCT_PENDING 0		/* T if work item pending execution */
+#define WORK_STRUCT_NOAUTOREL 1		/* F if work item automatically released on exec */
+#define WORK_STRUCT_FLAG_MASK (3UL)
+#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
 	struct list_head entry;
-	void (*func)(void *);
-	void *data;
-	void *wq_data;
+	work_func_t func;
+};
+
+#define WORK_DATA_INIT(autorelease) \
+	ATOMIC_LONG_INIT((autorelease) << WORK_STRUCT_NOAUTOREL)
+
+struct delayed_work {
+	struct work_struct work;
 	struct timer_list timer;
 };
 
@@ -24,77 +43,164 @@ struct execute_work {
 	struct work_struct work;
 };
 
-#define __WORK_INITIALIZER(n, f, d) {				\
+#define __WORK_INITIALIZER(n, f) {				\
+	.data = WORK_DATA_INIT(0),				\
+        .entry	= { &(n).entry, &(n).entry },			\
+	.func = (f),						\
+	}
+
+#define __WORK_INITIALIZER_NAR(n, f) {				\
+	.data = WORK_DATA_INIT(1),				\
         .entry	= { &(n).entry, &(n).entry },			\
 	.func = (f),						\
-	.data = (d),						\
+	}
+
+#define __DELAYED_WORK_INITIALIZER(n, f) {			\
+	.work = __WORK_INITIALIZER((n).work, (f)),		\
 	.timer = TIMER_INITIALIZER(NULL, 0, 0),			\
 	}
 
-#define DECLARE_WORK(n, f, d)					\
-	struct work_struct n = __WORK_INITIALIZER(n, f, d)
+#define __DELAYED_WORK_INITIALIZER_NAR(n, f) {			\
+	.work = __WORK_INITIALIZER_NAR((n).work, (f)),		\
+	.timer = TIMER_INITIALIZER(NULL, 0, 0),			\
+	}
+
+#define DECLARE_WORK(n, f)					\
+	struct work_struct n = __WORK_INITIALIZER(n, f)
+
+#define DECLARE_WORK_NAR(n, f)					\
+	struct work_struct n = __WORK_INITIALIZER_NAR(n, f)
+
+#define DECLARE_DELAYED_WORK(n, f)				\
+	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
+
+#define DECLARE_DELAYED_WORK_NAR(n, f)			\
+	struct dwork_struct n = __DELAYED_WORK_INITIALIZER_NAR(n, f)
 
 /*
- * initialize a work-struct's func and data pointers:
+ * initialize a work item's function pointer
  */
-#define PREPARE_WORK(_work, _func, _data)			\
+#define PREPARE_WORK(_work, _func)				\
 	do {							\
-		(_work)->func = _func;				\
-		(_work)->data = _data;				\
+		(_work)->func = (_func);			\
 	} while (0)
 
+#define PREPARE_DELAYED_WORK(_work, _func)			\
+	PREPARE_WORK(&(_work)->work, (_func))
+
 /*
- * initialize all of a work-struct:
+ * initialize all of a work item in one go
+ *
+ * NOTE! No point in using "atomic_long_set()": useing a direct
+ * assignment of the work data initializer allows the compiler
+ * to generate better code.
  */
-#define INIT_WORK(_work, _func, _data)				\
+#define INIT_WORK(_work, _func)					\
 	do {							\
+		(_work)->data = (atomic_long_t) WORK_DATA_INIT(0);	\
 		INIT_LIST_HEAD(&(_work)->entry);		\
-		(_work)->pending = 0;				\
-		PREPARE_WORK((_work), (_func), (_data));	\
+		PREPARE_WORK((_work), (_func));			\
+	} while (0)
+
+#define INIT_WORK_NAR(_work, _func)					\
+	do {								\
+		(_work)->data = (atomic_long_t) WORK_DATA_INIT(1);	\
+		INIT_LIST_HEAD(&(_work)->entry);			\
+		PREPARE_WORK((_work), (_func));				\
+	} while (0)
+
+#define INIT_DELAYED_WORK(_work, _func)				\
+	do {							\
+		INIT_WORK(&(_work)->work, (_func));		\
+		init_timer(&(_work)->timer);			\
+	} while (0)
+
+#define INIT_DELAYED_WORK_NAR(_work, _func)			\
+	do {							\
+		INIT_WORK_NAR(&(_work)->work, (_func));		\
 		init_timer(&(_work)->timer);			\
 	} while (0)
 
+/**
+ * work_pending - Find out whether a work item is currently pending
+ * @work: The work item in question
+ */
+#define work_pending(work) \
+	test_bit(WORK_STRUCT_PENDING, work_data_bits(work))
+
+/**
+ * delayed_work_pending - Find out whether a delayable work item is currently
+ * pending
+ * @work: The work item in question
+ */
+#define delayed_work_pending(w) \
+	work_pending(&(w)->work)
+
+/**
+ * work_release - Release a work item under execution
+ * @work: The work item to release
+ *
+ * This is used to release a work item that has been initialised with automatic
+ * release mode disabled (WORK_STRUCT_NOAUTOREL is set).  This gives the work
+ * function the opportunity to grab auxiliary data from the container of the
+ * work_struct before clearing the pending bit as the work_struct may be
+ * subject to deallocation the moment the pending bit is cleared.
+ *
+ * In such a case, this should be called in the work function after it has
+ * fetched any data it may require from the containter of the work_struct.
+ * After this function has been called, the work_struct may be scheduled for
+ * further execution or it may be deallocated unless other precautions are
+ * taken.
+ *
+ * This should also be used to release a delayed work item.
+ */
+#define work_release(work) \
+	clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))
+
+
 extern struct workqueue_struct *__create_workqueue(const char *name,
-						    int singlethread);
-#define create_workqueue(name) __create_workqueue((name), 0)
-#define create_singlethread_workqueue(name) __create_workqueue((name), 1)
+						    int singlethread,
+						    int freezeable);
+#define create_workqueue(name) __create_workqueue((name), 0, 0)
+#define create_freezeable_workqueue(name) __create_workqueue((name), 0, 1)
+#define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0)
 
 extern void destroy_workqueue(struct workqueue_struct *wq);
 
 extern int FASTCALL(queue_work(struct workqueue_struct *wq, struct work_struct *work));
-extern int FASTCALL(queue_delayed_work(struct workqueue_struct *wq, struct work_struct *work, unsigned long delay));
+extern int FASTCALL(queue_delayed_work(struct workqueue_struct *wq, struct delayed_work *work, unsigned long delay));
 extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
-	struct work_struct *work, unsigned long delay);
+	struct delayed_work *work, unsigned long delay);
 extern void FASTCALL(flush_workqueue(struct workqueue_struct *wq));
 
 extern int FASTCALL(schedule_work(struct work_struct *work));
-extern int FASTCALL(schedule_delayed_work(struct work_struct *work, unsigned long delay));
+extern int FASTCALL(run_scheduled_work(struct work_struct *work));
+extern int FASTCALL(schedule_delayed_work(struct delayed_work *work, unsigned long delay));
 
-extern int schedule_delayed_work_on(int cpu, struct work_struct *work, unsigned long delay);
-extern int schedule_on_each_cpu(void (*func)(void *info), void *info);
+extern int schedule_delayed_work_on(int cpu, struct delayed_work *work, unsigned long delay);
+extern int schedule_on_each_cpu(work_func_t func);
 extern void flush_scheduled_work(void);
 extern int current_is_keventd(void);
 extern int keventd_up(void);
 
 extern void init_workqueues(void);
-void cancel_rearming_delayed_work(struct work_struct *work);
+void cancel_rearming_delayed_work(struct delayed_work *work);
 void cancel_rearming_delayed_workqueue(struct workqueue_struct *,
-				       struct work_struct *);
-int execute_in_process_context(void (*fn)(void *), void *,
-			       struct execute_work *);
+				       struct delayed_work *);
+int execute_in_process_context(work_func_t fn, struct execute_work *);
 
 /*
  * Kill off a pending schedule_delayed_work().  Note that the work callback
  * function may still be running on return from cancel_delayed_work().  Run
  * flush_scheduled_work() to wait on it.
  */
-static inline int cancel_delayed_work(struct work_struct *work)
+static inline int cancel_delayed_work(struct delayed_work *work)
 {
 	int ret;
 
 	ret = del_timer_sync(&work->timer);
 	if (ret)
-		clear_bit(0, &work->pending);
+		work_release(&work->work);
 	return ret;
 }