[PATCH 02/15] workqueue: make queueing functions return bool

From: Tejun Heo
Date: Fri Jul 27 2012 - 19:58:24 EST


All queueing functions return 1 on success, 0 if the work item was
already pending. Update them to return bool instead. This signifies
better that they don't return 0 / -errno.

This is cleanup and doesn't cause any functional difference.

While at it, fix comment opening for schedule_work_on().

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
include/linux/workqueue.h | 20 +++++++++---------
kernel/workqueue.c | 47 ++++++++++++++++++++++-----------------------
2 files changed, 33 insertions(+), 34 deletions(-)

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 5970342..278dc5d 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -365,24 +365,24 @@ __alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active,

extern void destroy_workqueue(struct workqueue_struct *wq);

-extern int queue_work_on(int cpu, struct workqueue_struct *wq,
+extern bool queue_work_on(int cpu, struct workqueue_struct *wq,
struct work_struct *work);
-extern int queue_work(struct workqueue_struct *wq, struct work_struct *work);
-extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
+extern bool queue_work(struct workqueue_struct *wq, struct work_struct *work);
+extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
struct delayed_work *work, unsigned long delay);
-extern int queue_delayed_work(struct workqueue_struct *wq,
+extern bool queue_delayed_work(struct workqueue_struct *wq,
struct delayed_work *work, unsigned long delay);

extern void flush_workqueue(struct workqueue_struct *wq);
extern void drain_workqueue(struct workqueue_struct *wq);
extern void flush_scheduled_work(void);

-extern int schedule_work_on(int cpu, struct work_struct *work);
-extern int schedule_work(struct work_struct *work);
-extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
- unsigned long delay);
-extern int schedule_delayed_work(struct delayed_work *work,
- unsigned long delay);
+extern bool schedule_work_on(int cpu, struct work_struct *work);
+extern bool schedule_work(struct work_struct *work);
+extern bool schedule_delayed_work_on(int cpu, struct delayed_work *work,
+ unsigned long delay);
+extern bool schedule_delayed_work(struct delayed_work *work,
+ unsigned long delay);
extern int schedule_on_each_cpu(work_func_t func);
extern int keventd_up(void);

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 07d309e..70f95ab 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1058,19 +1058,19 @@ static void __queue_work(unsigned int cpu, struct workqueue_struct *wq,
* @wq: workqueue to use
* @work: work to queue
*
- * Returns 0 if @work was already on a queue, non-zero otherwise.
+ * Returns %false if @work was already on a queue, %true otherwise.
*
* We queue the work to a specific CPU, the caller must ensure it
* can't go away.
*/
-int
-queue_work_on(int cpu, struct workqueue_struct *wq, struct work_struct *work)
+bool queue_work_on(int cpu, struct workqueue_struct *wq,
+ struct work_struct *work)
{
- int ret = 0;
+ bool ret = false;

if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
__queue_work(cpu, wq, work);
- ret = 1;
+ ret = true;
}
return ret;
}
@@ -1081,14 +1081,14 @@ EXPORT_SYMBOL_GPL(queue_work_on);
* @wq: workqueue to use
* @work: work to queue
*
- * Returns 0 if @work was already on a queue, non-zero otherwise.
+ * Returns %false if @work was already on a queue, %true otherwise.
*
* We queue the work to the CPU on which it was submitted, but if the CPU dies
* it can be processed by another CPU.
*/
-int queue_work(struct workqueue_struct *wq, struct work_struct *work)
+bool queue_work(struct workqueue_struct *wq, struct work_struct *work)
{
- int ret;
+ bool ret;

ret = queue_work_on(get_cpu(), wq, work);
put_cpu();
@@ -1112,14 +1112,14 @@ static void delayed_work_timer_fn(unsigned long __data)
* @dwork: work to queue
* @delay: number of jiffies to wait before queueing
*
- * Returns 0 if @work was already on a queue, non-zero otherwise.
+ * Returns %false if @work was already on a queue, %true otherwise.
*/
-int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
- struct delayed_work *dwork, unsigned long delay)
+bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
+ struct delayed_work *dwork, unsigned long delay)
{
- int ret = 0;
struct timer_list *timer = &dwork->timer;
struct work_struct *work = &dwork->work;
+ bool ret = false;

if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
unsigned int lcpu;
@@ -1154,7 +1154,7 @@ int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
add_timer_on(timer, cpu);
else
add_timer(timer);
- ret = 1;
+ ret = true;
}
return ret;
}
@@ -1166,9 +1166,9 @@ EXPORT_SYMBOL_GPL(queue_delayed_work_on);
* @dwork: delayable work to queue
* @delay: number of jiffies to wait before queueing
*
- * Returns 0 if @work was already on a queue, non-zero otherwise.
+ * Returns %false if @work was already on a queue, %true otherwise.
*/
-int queue_delayed_work(struct workqueue_struct *wq,
+bool queue_delayed_work(struct workqueue_struct *wq,
struct delayed_work *dwork, unsigned long delay)
{
if (delay == 0)
@@ -2877,14 +2877,14 @@ bool cancel_delayed_work_sync(struct delayed_work *dwork)
}
EXPORT_SYMBOL(cancel_delayed_work_sync);

-/*
+/**
* schedule_work_on - put work task on a specific cpu
* @cpu: cpu to put the work task on
* @work: job to be done
*
* This puts a job on a specific cpu
*/
-int schedule_work_on(int cpu, struct work_struct *work)
+bool schedule_work_on(int cpu, struct work_struct *work)
{
return queue_work_on(cpu, system_wq, work);
}
@@ -2894,14 +2894,14 @@ EXPORT_SYMBOL(schedule_work_on);
* schedule_work - put work task in global workqueue
* @work: job to be done
*
- * Returns zero if @work was already on the kernel-global workqueue and
- * non-zero otherwise.
+ * Returns %false if @work was already on the kernel-global workqueue and
+ * %true otherwise.
*
* This puts a job in the kernel-global workqueue if it was not already
* queued and leaves it in the same position on the kernel-global
* workqueue otherwise.
*/
-int schedule_work(struct work_struct *work)
+bool schedule_work(struct work_struct *work)
{
return queue_work(system_wq, work);
}
@@ -2916,8 +2916,8 @@ EXPORT_SYMBOL(schedule_work);
* After waiting for a given time this puts a job in the kernel-global
* workqueue on the specified CPU.
*/
-int schedule_delayed_work_on(int cpu,
- struct delayed_work *dwork, unsigned long delay)
+bool schedule_delayed_work_on(int cpu, struct delayed_work *dwork,
+ unsigned long delay)
{
return queue_delayed_work_on(cpu, system_wq, dwork, delay);
}
@@ -2931,8 +2931,7 @@ EXPORT_SYMBOL(schedule_delayed_work_on);
* After waiting for a given time this puts a job in the kernel-global
* workqueue.
*/
-int schedule_delayed_work(struct delayed_work *dwork,
- unsigned long delay)
+bool schedule_delayed_work(struct delayed_work *dwork, unsigned long delay)
{
return queue_delayed_work(system_wq, dwork, delay);
}
--
1.7.7.3

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