Merge branch 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/…

…git/tj/wq

Pull workqueue updates from Tejun Heo:
 "Nothing major. I introduced a flag collsion bug during v4.13 cycle
  which is fixed in this pull request. Fortunately, the flag is for
  debugging / verification and the bug isn't critical"

* 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Fix flag collision
  workqueue: Use TASK_IDLE
  workqueue: fix path to documentation
  workqueue: doc change for ST behavior on NUMA systems

Documentation/core-api/workqueue.rst

@@ -243,11 +243,15 @@ throttling the number of active work items, specifying '0' is
 recommended.
 
 Some users depend on the strict execution ordering of ST wq.  The
-combination of ``@max_active`` of 1 and ``WQ_UNBOUND`` is used to
-achieve this behavior.  Work items on such wq are always queued to the
-unbound worker-pools and only one work item can be active at any given
+combination of ``@max_active`` of 1 and ``WQ_UNBOUND`` used to
+achieve this behavior.  Work items on such wq were always queued to the
+unbound worker-pools and only one work item could be active at any given
 time thus achieving the same ordering property as ST wq.
 
+In the current implementation the above configuration only guarantees
+ST behavior within a given NUMA node. Instead alloc_ordered_queue should
+be used to achieve system wide ST behavior.
+
 
 Example Execution Scenarios
 ===========================

include/linux/workqueue.h

@@ -323,8 +323,8 @@ enum {
 
 	__WQ_DRAINING		= 1 << 16, /* internal: workqueue is draining */
 	__WQ_ORDERED		= 1 << 17, /* internal: workqueue is ordered */
-	__WQ_ORDERED_EXPLICIT	= 1 << 18, /* internal: alloc_ordered_workqueue() */
 	__WQ_LEGACY		= 1 << 18, /* internal: create*_workqueue() */
+	__WQ_ORDERED_EXPLICIT	= 1 << 19, /* internal: alloc_ordered_workqueue() */
 
 	WQ_MAX_ACTIVE		= 512,	  /* I like 512, better ideas? */
 	WQ_MAX_UNBOUND_PER_CPU	= 4,	  /* 4 * #cpus for unbound wq */

kernel/workqueue.c

@@ -21,7 +21,7 @@
  * pools for workqueues which are not bound to any specific CPU - the
  * number of these backing pools is dynamic.
  *
- * Please read Documentation/workqueue.txt for details.
+ * Please read Documentation/core-api/workqueue.rst for details.
  */
 
 #include <linux/export.h>
@@ -2269,7 +2269,7 @@ static int worker_thread(void *__worker)
 	 * event.
 	 */
 	worker_enter_idle(worker);
-	__set_current_state(TASK_INTERRUPTIBLE);
+	__set_current_state(TASK_IDLE);
 	spin_unlock_irq(&pool->lock);
 	schedule();
 	goto woke_up;
@@ -2311,7 +2311,7 @@ static int rescuer_thread(void *__rescuer)
 	 */
 	rescuer->task->flags |= PF_WQ_WORKER;
 repeat:
-	set_current_state(TASK_INTERRUPTIBLE);
+	set_current_state(TASK_IDLE);
 
 	/*
 	 * By the time the rescuer is requested to stop, the workqueue