Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue update from Tejun Heo:
 "Workqueue changes for v4.5.  One cleanup patch and three to improve
  the debuggability.

  Workqueue now has a stall detector which dumps workqueue state if any
  worker pool hasn't made forward progress over a certain amount of time
  (30s by default) and also triggers a warning if a workqueue which can
  be used in memory reclaim path tries to wait on something which can't
  be.

  These should make workqueue hangs a lot easier to debug."

* 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: simplify the apply_workqueue_attrs_locked()
  workqueue: implement lockup detector
  watchdog: introduce touch_softlockup_watchdog_sched()
  workqueue: warn if memory reclaim tries to flush !WQ_MEM_RECLAIM workqueue

Documentation/kernel-parameters.txt

@@ -4140,6 +4140,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			or other driver-specific files in the
 			Documentation/watchdog/ directory.
 
+	workqueue.watchdog_thresh=
+			If CONFIG_WQ_WATCHDOG is configured, workqueue can
+			warn stall conditions and dump internal state to
+			help debugging.  0 disables workqueue stall
+			detection; otherwise, it's the stall threshold
+			duration in seconds.  The default value is 30 and
+			it can be updated at runtime by writing to the
+			corresponding sysfs file.
+
 	workqueue.disable_numa
 			By default, all work items queued to unbound
 			workqueues are affine to the NUMA nodes they're