patch1&2 are simple cleaups and reflect to recently changes.
patch3 just moves code.
Cc: Tejun Heo <[email protected]>
Lai Jiangshan (3):
workqueue: remove the declaration of copy_workqueue_attrs()
workqueue: remove the lock from wq_sysfs_prep_attrs()
workqueue: move flush_scheduled_work() to workqueue.h
include/linux/workqueue.h | 30 +++++++++++++++++++++++++++++-
kernel/workqueue.c | 36 ++----------------------------------
2 files changed, 31 insertions(+), 35 deletions(-)
--
2.1.0
This pre-declaration was unneeded since a previous refactor patch
6ba94429c8e7 ("workqueue: Reorder sysfs code").
Signed-off-by: Lai Jiangshan <[email protected]>
---
kernel/workqueue.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index ee5bf95..a04a9cd3 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -337,8 +337,6 @@ struct workqueue_struct *system_freezable_power_efficient_wq __read_mostly;
EXPORT_SYMBOL_GPL(system_freezable_power_efficient_wq);
static int worker_thread(void *__worker);
-static void copy_workqueue_attrs(struct workqueue_attrs *to,
- const struct workqueue_attrs *from);
static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
#define CREATE_TRACE_POINTS
--
2.1.0
Reading to wq->unbound_attrs requires protection of either wq_pool_mutex
or wq->mutex, and wq_sysfs_prep_attrs() is called with wq_pool_mutex held,
so we don't need to grab wq->mutex here.
Signed-off-by: Lai Jiangshan <[email protected]>
---
kernel/workqueue.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index a04a9cd3..81b0e0d 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4941,13 +4941,13 @@ static struct workqueue_attrs *wq_sysfs_prep_attrs(struct workqueue_struct *wq)
{
struct workqueue_attrs *attrs;
+ lockdep_assert_held(&wq_pool_mutex);
+
attrs = alloc_workqueue_attrs(GFP_KERNEL);
if (!attrs)
return NULL;
- mutex_lock(&wq->mutex);
copy_workqueue_attrs(attrs, wq->unbound_attrs);
- mutex_unlock(&wq->mutex);
return attrs;
}
--
2.1.0
flush_scheduled_work() is just a simple call to flush_work().
Signed-off-by: Lai Jiangshan <[email protected]>
---
include/linux/workqueue.h | 30 +++++++++++++++++++++++++++++-
kernel/workqueue.c | 30 ------------------------------
2 files changed, 29 insertions(+), 31 deletions(-)
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 4618dd6..738b30b 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -435,7 +435,6 @@ extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
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_on_each_cpu(work_func_t func);
@@ -532,6 +531,35 @@ static inline bool schedule_work(struct work_struct *work)
}
/**
+ * flush_scheduled_work - ensure that any scheduled work has run to completion.
+ *
+ * Forces execution of the kernel-global workqueue and blocks until its
+ * completion.
+ *
+ * Think twice before calling this function! It's very easy to get into
+ * trouble if you don't take great care. Either of the following situations
+ * will lead to deadlock:
+ *
+ * One of the work items currently on the workqueue needs to acquire
+ * a lock held by your code or its caller.
+ *
+ * Your code is running in the context of a work routine.
+ *
+ * They will be detected by lockdep when they occur, but the first might not
+ * occur very often. It depends on what work items are on the workqueue and
+ * what locks they need, which you have no control over.
+ *
+ * In most situations flushing the entire workqueue is overkill; you merely
+ * need to know that a particular work item isn't queued and isn't running.
+ * In such cases you should use cancel_delayed_work_sync() or
+ * cancel_work_sync() instead.
+ */
+static inline void flush_scheduled_work(void)
+{
+ flush_workqueue(system_wq);
+}
+
+/**
* schedule_delayed_work_on - queue work in global workqueue on CPU after delay
* @cpu: cpu to use
* @dwork: job to be done
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 81b0e0d..097fc48 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -2959,36 +2959,6 @@ int schedule_on_each_cpu(work_func_t func)
}
/**
- * flush_scheduled_work - ensure that any scheduled work has run to completion.
- *
- * Forces execution of the kernel-global workqueue and blocks until its
- * completion.
- *
- * Think twice before calling this function! It's very easy to get into
- * trouble if you don't take great care. Either of the following situations
- * will lead to deadlock:
- *
- * One of the work items currently on the workqueue needs to acquire
- * a lock held by your code or its caller.
- *
- * Your code is running in the context of a work routine.
- *
- * They will be detected by lockdep when they occur, but the first might not
- * occur very often. It depends on what work items are on the workqueue and
- * what locks they need, which you have no control over.
- *
- * In most situations flushing the entire workqueue is overkill; you merely
- * need to know that a particular work item isn't queued and isn't running.
- * In such cases you should use cancel_delayed_work_sync() or
- * cancel_work_sync() instead.
- */
-void flush_scheduled_work(void)
-{
- flush_workqueue(system_wq);
-}
-EXPORT_SYMBOL(flush_scheduled_work);
-
-/**
* execute_in_process_context - reliably execute the routine with user context
* @fn: the function to execute
* @ew: guaranteed storage for the execute work structure (must
--
2.1.0
On Wed, May 20, 2015 at 02:41:16PM +0800, Lai Jiangshan wrote:
> patch1&2 are simple cleaups and reflect to recently changes.
>
> patch3 just moves code.
Applied 1-3 to wq/for-4.2.
Thanks.
--
tejun