From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri, 24 Aug 2018 20:16:36 +0000 (-0700)
Subject: Merge branch 'for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
X-Git-Tag: v4.19-rc1~20
X-Git-Url: http://git.samba.org/samba.git/?p=sfrench%2Fcifs-2.6.git;a=commitdiff_plain;h=9022ada8ab6f1f1a932a3c93815061042e6548a5;hp=-c

Merge branch 'for-4.19' of git://git./linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:
 "Over the lockdep cross-release churn, workqueue lost some of the
  existing annotations. Johannes Berg restored it and also improved
  them"

* 'for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: re-add lockdep dependencies for flushing
  workqueue: skip lockdep wq dependency in cancel_work_sync()
---

9022ada8ab6f1f1a932a3c93815061042e6548a5
diff --combined kernel/workqueue.c
index 78b192071ef7,661184fcd503..60e80198c3df
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@@ -2652,6 -2652,9 +2652,9 @@@ void flush_workqueue(struct workqueue_s
  	if (WARN_ON(!wq_online))
  		return;
  
+ 	lock_map_acquire(&wq->lockdep_map);
+ 	lock_map_release(&wq->lockdep_map);
+ 
  	mutex_lock(&wq->mutex);
  
  	/*
@@@ -2843,7 -2846,8 +2846,8 @@@ reflush
  }
  EXPORT_SYMBOL_GPL(drain_workqueue);
  
- static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
+ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr,
+ 			     bool from_cancel)
  {
  	struct worker *worker = NULL;
  	struct worker_pool *pool;
@@@ -2885,7 -2889,8 +2889,8 @@@
  	 * workqueues the deadlock happens when the rescuer stalls, blocking
  	 * forward progress.
  	 */
- 	if (pwq->wq->saved_max_active == 1 || pwq->wq->rescuer) {
+ 	if (!from_cancel &&
+ 	    (pwq->wq->saved_max_active == 1 || pwq->wq->rescuer)) {
  		lock_map_acquire(&pwq->wq->lockdep_map);
  		lock_map_release(&pwq->wq->lockdep_map);
  	}
@@@ -2896,6 -2901,27 +2901,27 @@@ already_gone
  	return false;
  }
  
+ static bool __flush_work(struct work_struct *work, bool from_cancel)
+ {
+ 	struct wq_barrier barr;
+ 
+ 	if (WARN_ON(!wq_online))
+ 		return false;
+ 
+ 	if (!from_cancel) {
+ 		lock_map_acquire(&work->lockdep_map);
+ 		lock_map_release(&work->lockdep_map);
+ 	}
+ 
+ 	if (start_flush_work(work, &barr, from_cancel)) {
+ 		wait_for_completion(&barr.done);
+ 		destroy_work_on_stack(&barr.work);
+ 		return true;
+ 	} else {
+ 		return false;
+ 	}
+ }
+ 
  /**
   * flush_work - wait for a work to finish executing the last queueing instance
   * @work: the work to flush
@@@ -2909,18 -2935,7 +2935,7 @@@
   */
  bool flush_work(struct work_struct *work)
  {
- 	struct wq_barrier barr;
- 
- 	if (WARN_ON(!wq_online))
- 		return false;
- 
- 	if (start_flush_work(work, &barr)) {
- 		wait_for_completion(&barr.done);
- 		destroy_work_on_stack(&barr.work);
- 		return true;
- 	} else {
- 		return false;
- 	}
+ 	return __flush_work(work, false);
  }
  EXPORT_SYMBOL_GPL(flush_work);
  
@@@ -2986,7 -3001,7 +3001,7 @@@ static bool __cancel_work_timer(struct 
  	 * isn't executing.
  	 */
  	if (wq_online)
- 		flush_work(work);
+ 		__flush_work(work, true);
  
  	clear_work_data(work);
  
@@@ -3714,7 -3729,8 +3729,7 @@@ apply_wqattrs_prepare(struct workqueue_
  
  	lockdep_assert_held(&wq_pool_mutex);
  
 -	ctx = kzalloc(sizeof(*ctx) + nr_node_ids * sizeof(ctx->pwq_tbl[0]),
 -		      GFP_KERNEL);
 +	ctx = kzalloc(struct_size(ctx, pwq_tbl, nr_node_ids), GFP_KERNEL);
  
  	new_attrs = alloc_workqueue_attrs(GFP_KERNEL);
  	tmp_attrs = alloc_workqueue_attrs(GFP_KERNEL);
@@@ -4362,7 -4378,6 +4377,7 @@@ void set_worker_desc(const char *fmt, .
  		va_end(args);
  	}
  }
 +EXPORT_SYMBOL_GPL(set_worker_desc);
  
  /**
   * print_worker_info - print out worker information and description
@@@ -5638,7 -5653,7 +5653,7 @@@ static void __init wq_numa_init(void
  	 * available.  Build one from cpu_to_node() which should have been
  	 * fully initialized by now.
  	 */
 -	tbl = kzalloc(nr_node_ids * sizeof(tbl[0]), GFP_KERNEL);
 +	tbl = kcalloc(nr_node_ids, sizeof(tbl[0]), GFP_KERNEL);
  	BUG_ON(!tbl);
  
  	for_each_node(node)