workqueue: Make @flags handling consistent across set_work_data() and friends

- set_work_data() takes a separate @flags argument but just ORs it to @data.
  This is more confusing than helpful. Just take @data.

- Use the name @flags consistently and add the parameter to
  set_work_pool_and_{keep|clear}_pending(). This will be used by the planned
  disable/enable support.

No functional changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>

kernel/workqueue.c

@@ -777,29 +777,28 @@ static int work_next_color(int color)
  * but stay off timer and worklist for arbitrarily long and nobody should
  * try to steal the PENDING bit.
  */
-static inline void set_work_data(struct work_struct *work, unsigned long data,
-				 unsigned long flags)
+static inline void set_work_data(struct work_struct *work, unsigned long data)
 {
 	WARN_ON_ONCE(!work_pending(work));
-	atomic_long_set(&work->data, data | flags | work_static(work));
+	atomic_long_set(&work->data, data | work_static(work));
 }
 
 static void set_work_pwq(struct work_struct *work, struct pool_workqueue *pwq,
-			 unsigned long extra_flags)
+			 unsigned long flags)
 {
-	set_work_data(work, (unsigned long)pwq,
-		      WORK_STRUCT_PENDING | WORK_STRUCT_PWQ | extra_flags);
+	set_work_data(work, (unsigned long)pwq | WORK_STRUCT_PENDING |
+		      WORK_STRUCT_PWQ | flags);
 }
 
 static void set_work_pool_and_keep_pending(struct work_struct *work,
-					   int pool_id)
+					   int pool_id, unsigned long flags)
 {
-	set_work_data(work, (unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT,
-		      WORK_STRUCT_PENDING);
+	set_work_data(work, ((unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT) |
+		      WORK_STRUCT_PENDING | flags);
 }
 
 static void set_work_pool_and_clear_pending(struct work_struct *work,
-					    int pool_id)
+					    int pool_id, unsigned long flags)
 {
 	/*
 	 * The following wmb is paired with the implied mb in
@@ -808,7 +807,8 @@ static void set_work_pool_and_clear_pending(struct work_struct *work,
 	 * owner.
 	 */
 	smp_wmb();
-	set_work_data(work, (unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT, 0);
+	set_work_data(work, ((unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT) |
+		      flags);
 	/*
 	 * The following mb guarantees that previous clear of a PENDING bit
 	 * will not be reordered with any speculative LOADS or STORES from
@@ -909,7 +909,7 @@ static void mark_work_canceling(struct work_struct *work)
 	unsigned long pool_id = get_work_pool_id(work);
 
 	pool_id <<= WORK_OFFQ_POOL_SHIFT;
-	set_work_data(work, pool_id | WORK_OFFQ_CANCELING, WORK_STRUCT_PENDING);
+	set_work_data(work, pool_id | WORK_STRUCT_PENDING | WORK_OFFQ_CANCELING);
 }
 
 static bool work_is_canceling(struct work_struct *work)
@@ -2127,7 +2127,7 @@ static int try_to_grab_pending(struct work_struct *work, u32 cflags,
 		 * this destroys work->data needed by the next step, stash it.
 		 */
 		work_data = *work_data_bits(work);
-		set_work_pool_and_keep_pending(work, pool->id);
+		set_work_pool_and_keep_pending(work, pool->id, 0);
 
 		/* must be the last step, see the function comment */
 		pwq_dec_nr_in_flight(pwq, work_data);
@@ -3205,7 +3205,7 @@ __acquires(&pool->lock)
 	 * PENDING and queued state changes happen together while IRQ is
 	 * disabled.
 	 */
-	set_work_pool_and_clear_pending(work, pool->id);
+	set_work_pool_and_clear_pending(work, pool->id, 0);
 
 	pwq->stats[PWQ_STAT_STARTED]++;
 	raw_spin_unlock_irq(&pool->lock);
@@ -4188,7 +4188,7 @@ static bool __cancel_work(struct work_struct *work, u32 cflags)
 	if (unlikely(ret < 0))
 		return false;
 
-	set_work_pool_and_clear_pending(work, get_work_pool_id(work));
+	set_work_pool_and_clear_pending(work, get_work_pool_id(work), 0);
 	local_irq_restore(irq_flags);
 	return ret;
 }
@@ -4215,7 +4215,7 @@ static bool __cancel_work_sync(struct work_struct *work, u32 cflags)
 	 * with prepare_to_wait() above so that either waitqueue_active() is
 	 * visible here or !work_is_canceling() is visible there.
 	 */
-	set_work_pool_and_clear_pending(work, WORK_OFFQ_POOL_NONE);
+	set_work_pool_and_clear_pending(work, WORK_OFFQ_POOL_NONE, 0);
 
 	if (waitqueue_active(&wq_cancel_waitq))
 		__wake_up(&wq_cancel_waitq, TASK_NORMAL, 1, work);