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.

Tejun Heo committed 14 years ago

Commit d8e794d1 parent 8930cab2 files · +15 −5Browse files

Unified · Split

2 files

include/linux/workqueue.h +11 −2
kernel/workqueue.c +4 −3

include/linux/workqueue.h+11−2

@@ -16,6 +16,7 @@ struct workqueue_struct; · 15 unmodified lines
16	16
17	17	struct work_struct;
18	18	typedef void (work_func_t)(struct work_struct work);
	19	+void delayed_work_timer_fn(unsigned long __data);
19	20
20	21	/*
21	22	* The first word is the work queue pointer and the flags rolled into
@@ -124,12 +125,14 @@ struct execute_work { · 102 unmodified lines
124	125
125	126	#define __DELAYED_WORK_INITIALIZER(n, f) { \
126	127	.work = __WORK_INITIALIZER((n).work, (f)), \
127		− .timer = TIMER_INITIALIZER(NULL, 0, 0), \
	128	+ .timer = TIMER_INITIALIZER(delayed_work_timer_fn, \
	129	+ 0, (unsigned long)&(n)), \
128	130	}
129	131
130	132	#define __DEFERRED_WORK_INITIALIZER(n, f) { \
131	133	.work = __WORK_INITIALIZER((n).work, (f)), \
132		− .timer = TIMER_DEFERRED_INITIALIZER(NULL, 0, 0), \
	134	+ .timer = TIMER_DEFERRED_INITIALIZER(delayed_work_timer_fn, \
	135	+ 0, (unsigned long)&(n)), \
133	136	}
134	137
135	138	#define DECLARE_WORK(n, f) \
@@ -207,18 +210,24 @@ static inline unsigned int work_static(struct work_struct *work) { return 0; } · 71 unmodified lines
207	210	do { \
208	211	INIT_WORK(&(_work)->work, (_func)); \
209	212	init_timer(&(_work)->timer); \
	213	+ (_work)->timer.function = delayed_work_timer_fn;\
	214	+ (_work)->timer.data = (unsigned long)(_work); \
210	215	} while (0)
211	216
212	217	#define INIT_DELAYED_WORK_ONSTACK(_work, _func) \
213	218	do { \
214	219	INIT_WORK_ONSTACK(&(_work)->work, (_func)); \
215	220	init_timer_on_stack(&(_work)->timer); \
	221	+ (_work)->timer.function = delayed_work_timer_fn;\
	222	+ (_work)->timer.data = (unsigned long)(_work); \
216	223	} while (0)
217	224
218	225	#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
219	226	do { \
220	227	INIT_WORK(&(_work)->work, (_func)); \
221	228	init_timer_deferrable(&(_work)->timer); \
	229	+ (_work)->timer.function = delayed_work_timer_fn;\
	230	+ (_work)->timer.data = (unsigned long)(_work); \
222	231	} while (0)
223	232
224	233	/**

kernel/workqueue.c+4−3

@@ -1112,7 +1112,7 @@ bool queue_work(struct workqueue_struct wq, struct work_struct work) · 1111 unmodified lines
1112	1112	}
1113	1113	EXPORT_SYMBOL_GPL(queue_work);
1114	1114
1115		−static void delayed_work_timer_fn(unsigned long __data)
	1115	+void delayed_work_timer_fn(unsigned long __data)
1116	1116	{
1117	1117	struct delayed_work dwork = (struct delayed_work )__data;
1118	1118	struct cpu_workqueue_struct *cwq = get_work_cwq(&dwork->work);
@@ -1121,6 +1121,7 @@ static void delayed_work_timer_fn(unsigned long __data) · 2 unmodified lines
1121	1121	__queue_work(smp_processor_id(), cwq->wq, &dwork->work);
1122	1122	local_irq_enable();
1123	1123	}
	1124	+EXPORT_SYMBOL_GPL(delayed_work_timer_fn);
1124	1125
1125	1126	/**
1126	1127	* queue_delayed_work_on - queue work on specific CPU after delay
@@ -1145,6 +1146,8 @@ bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq, · 18 unmodified lines
1145	1146	if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
1146	1147	unsigned int lcpu;
1147	1148
	1149	+ WARN_ON_ONCE(timer->function != delayed_work_timer_fn \|\|
	1150	+ timer->data != (unsigned long)dwork);
1148	1151	BUG_ON(timer_pending(timer));
1149	1152	BUG_ON(!list_empty(&work->entry));
1150	1153
@@ -1168,8 +1171,6 @@ bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq, · 17 unmodified lines
1168	1171	set_work_cwq(work, get_cwq(lcpu, wq), 0);
1169	1172
1170	1173	timer->expires = jiffies + delay;
1171		− timer->data = (unsigned long)dwork;
1172		− timer->function = delayed_work_timer_fn;
1173	1174
1174	1175	if (unlikely(cpu >= 0))
1175	1176	add_timer_on(timer, cpu);