workqueue: set delayed_work->timer function on initialization
delayed_work->timer.function is currently initialized during
queue_delayed_work_on(). Export delayed_work_timer_fn() and set
delayed_work timer function during delayed_work initialization
together with other fields.
This ensures the timer function is always valid on an initialized
delayed_work. This is to help mod_delayed_work() implementation.
To detect delayed_work users which diddle with the internal timer,
trigger WARN if timer function doesn't match on queue.
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 278dc5d..ab95fef 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -16,6 +16,7 @@
struct work_struct;
typedef void (*work_func_t)(struct work_struct *work);
+void delayed_work_timer_fn(unsigned long __data);
/*
* The first word is the work queue pointer and the flags rolled into
@@ -124,12 +125,14 @@
#define __DELAYED_WORK_INITIALIZER(n, f) { \
.work = __WORK_INITIALIZER((n).work, (f)), \
- .timer = TIMER_INITIALIZER(NULL, 0, 0), \
+ .timer = TIMER_INITIALIZER(delayed_work_timer_fn, \
+ 0, (unsigned long)&(n)), \
}
#define __DEFERRED_WORK_INITIALIZER(n, f) { \
.work = __WORK_INITIALIZER((n).work, (f)), \
- .timer = TIMER_DEFERRED_INITIALIZER(NULL, 0, 0), \
+ .timer = TIMER_DEFERRED_INITIALIZER(delayed_work_timer_fn, \
+ 0, (unsigned long)&(n)), \
}
#define DECLARE_WORK(n, f) \
@@ -207,18 +210,24 @@
do { \
INIT_WORK(&(_work)->work, (_func)); \
init_timer(&(_work)->timer); \
+ (_work)->timer.function = delayed_work_timer_fn;\
+ (_work)->timer.data = (unsigned long)(_work); \
} while (0)
#define INIT_DELAYED_WORK_ONSTACK(_work, _func) \
do { \
INIT_WORK_ONSTACK(&(_work)->work, (_func)); \
init_timer_on_stack(&(_work)->timer); \
+ (_work)->timer.function = delayed_work_timer_fn;\
+ (_work)->timer.data = (unsigned long)(_work); \
} while (0)
#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
do { \
INIT_WORK(&(_work)->work, (_func)); \
init_timer_deferrable(&(_work)->timer); \
+ (_work)->timer.function = delayed_work_timer_fn;\
+ (_work)->timer.data = (unsigned long)(_work); \
} while (0)
/**