[PATCH 08/35] workqueue: define masks for work flags and conditionalize STATIC flags

From: Tejun Heo
Date: Mon Jun 28 2010 - 17:09:23 EST


Work flags are about to see more traditional mask handling. Define
WORK_STRUCT_*_BIT as the bit position constant and redefine
WORK_STRUCT_* as bit masks. Also, make WORK_STRUCT_STATIC_* flags
conditional

While at it, re-define these constants as enums and use
WORK_STRUCT_STATIC instead of hard-coding 2 in
WORK_DATA_STATIC_INIT().

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
include/linux/workqueue.h | 29 +++++++++++++++++++++--------
kernel/workqueue.c | 12 ++++++------
2 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index d89cfc1..d60c570 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -22,12 +22,25 @@ typedef void (*work_func_t)(struct work_struct *work);
*/
#define work_data_bits(work) ((unsigned long *)(&(work)->data))

+enum {
+ WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */
+#ifdef CONFIG_DEBUG_OBJECTS_WORK
+ WORK_STRUCT_STATIC_BIT = 1, /* static initializer (debugobjects) */
+#endif
+
+ WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
+#ifdef CONFIG_DEBUG_OBJECTS_WORK
+ WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
+#else
+ WORK_STRUCT_STATIC = 0,
+#endif
+
+ WORK_STRUCT_FLAG_MASK = 3UL,
+ WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
+};
+
struct work_struct {
atomic_long_t data;
-#define WORK_STRUCT_PENDING 0 /* T if work item pending execution */
-#define WORK_STRUCT_STATIC 1 /* static initializer (debugobjects) */
-#define WORK_STRUCT_FLAG_MASK (3UL)
-#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
struct list_head entry;
work_func_t func;
#ifdef CONFIG_LOCKDEP
@@ -36,7 +49,7 @@ struct work_struct {
};

#define WORK_DATA_INIT() ATOMIC_LONG_INIT(0)
-#define WORK_DATA_STATIC_INIT() ATOMIC_LONG_INIT(2)
+#define WORK_DATA_STATIC_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_STATIC)

struct delayed_work {
struct work_struct work;
@@ -98,7 +111,7 @@ extern void __init_work(struct work_struct *work, int onstack);
extern void destroy_work_on_stack(struct work_struct *work);
static inline unsigned int work_static(struct work_struct *work)
{
- return *work_data_bits(work) & (1 << WORK_STRUCT_STATIC);
+ return *work_data_bits(work) & WORK_STRUCT_STATIC;
}
#else
static inline void __init_work(struct work_struct *work, int onstack) { }
@@ -167,7 +180,7 @@ static inline unsigned int work_static(struct work_struct *work) { return 0; }
* @work: The work item in question
*/
#define work_pending(work) \
- test_bit(WORK_STRUCT_PENDING, work_data_bits(work))
+ test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))

/**
* delayed_work_pending - Find out whether a delayable work item is currently
@@ -182,7 +195,7 @@ static inline unsigned int work_static(struct work_struct *work) { return 0; }
* @work: The work item in question
*/
#define work_clear_pending(work) \
- clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))
+ clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))

enum {
WQ_FREEZEABLE = 1 << 0, /* freeze during suspend */
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 68e4dd8..5c49d76 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -115,7 +115,7 @@ static int work_fixup_activate(void *addr, enum debug_obj_state state)
* statically initialized. We just make sure that it
* is tracked in the object tracker.
*/
- if (test_bit(WORK_STRUCT_STATIC, work_data_bits(work))) {
+ if (test_bit(WORK_STRUCT_STATIC_BIT, work_data_bits(work))) {
debug_object_init(work, &work_debug_descr);
debug_object_activate(work, &work_debug_descr);
return 0;
@@ -232,7 +232,7 @@ static inline void set_wq_data(struct work_struct *work,
BUG_ON(!work_pending(work));

atomic_long_set(&work->data, (unsigned long)cwq | work_static(work) |
- (1UL << WORK_STRUCT_PENDING) | extra_flags);
+ WORK_STRUCT_PENDING | extra_flags);
}

/*
@@ -330,7 +330,7 @@ queue_work_on(int cpu, struct workqueue_struct *wq, struct work_struct *work)
{
int ret = 0;

- if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) {
+ if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
__queue_work(cpu, wq, work);
ret = 1;
}
@@ -380,7 +380,7 @@ int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
struct timer_list *timer = &dwork->timer;
struct work_struct *work = &dwork->work;

- if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) {
+ if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
BUG_ON(timer_pending(timer));
BUG_ON(!list_empty(&work->entry));

@@ -516,7 +516,7 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
* might deadlock.
*/
INIT_WORK_ON_STACK(&barr->work, wq_barrier_func);
- __set_bit(WORK_STRUCT_PENDING, work_data_bits(&barr->work));
+ __set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(&barr->work));
init_completion(&barr->done);

debug_work_activate(&barr->work);
@@ -628,7 +628,7 @@ static int try_to_grab_pending(struct work_struct *work)
struct cpu_workqueue_struct *cwq;
int ret = -1;

- if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work)))
+ if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work)))
return 0;

/*
--
1.6.4.2

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