workqueue: import refresh with rcu_read_lock conversion squishedrt-v4.8-10067-g513a4befae06

3 files changed, 17 insertions, 65 deletions

diff --git a/patches/series b/patches/series
index bb821029d05093..66f77404dd1636 100644
--- a/patches/series
+++ b/patches/series
@@ -401,7 +401,6 @@ fs-dcache-use-swait_queue-instead-of-waitqueue.patch
 # WORKQUEUE more fixes
 workqueue-use-rcu.patch
 workqueue-use-locallock.patch
-workqueue-use-rcu_readlock-in-put_pwq_unlocked.patch
 work-queue-work-around-irqsafe-timer-optimization.patch
 workqueue-distangle-from-rq-lock.patch
 
diff --git a/patches/workqueue-use-locallock.patch b/patches/workqueue-use-locallock.patch
index e03df16434a898..ffc72b923722ce 100644
--- a/patches/workqueue-use-locallock.patch
+++ b/patches/workqueue-use-locallock.patch
@@ -7,8 +7,8 @@ semantic of irq-off in regard to the pool->lock and remain preemptible.
 
 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
 ---
- kernel/workqueue.c |   31 +++++++++++++++++--------------
- 1 file changed, 17 insertions(+), 14 deletions(-)
+ kernel/workqueue.c |   33 +++++++++++++++++++--------------
+ 1 file changed, 19 insertions(+), 14 deletions(-)
 
 --- a/kernel/workqueue.c
 +++ b/kernel/workqueue.c
@@ -29,19 +29,21 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  static int worker_thread(void *__worker);
  static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
  
-@@ -1101,9 +1104,9 @@ static void put_pwq_unlocked(struct pool
+@@ -1101,9 +1104,11 @@ static void put_pwq_unlocked(struct pool
  		 * As both pwqs and pools are RCU protected, the
  		 * following lock operations are safe.
  		 */
 -		spin_lock_irq(&pwq->pool->lock);
++		rcu_read_lock();
 +		local_spin_lock_irq(pendingb_lock, &pwq->pool->lock);
  		put_pwq(pwq);
 -		spin_unlock_irq(&pwq->pool->lock);
 +		local_spin_unlock_irq(pendingb_lock, &pwq->pool->lock);
++		rcu_read_unlock();
  	}
  }
  
-@@ -1207,7 +1210,7 @@ static int try_to_grab_pending(struct wo
+@@ -1207,7 +1212,7 @@ static int try_to_grab_pending(struct wo
  	struct worker_pool *pool;
  	struct pool_workqueue *pwq;
  
@@ -50,7 +52,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  
  	/* try to steal the timer if it exists */
  	if (is_dwork) {
-@@ -1271,7 +1274,7 @@ static int try_to_grab_pending(struct wo
+@@ -1271,7 +1276,7 @@ static int try_to_grab_pending(struct wo
  	spin_unlock(&pool->lock);
  fail:
  	rcu_read_unlock();
@@ -59,7 +61,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  	if (work_is_canceling(work))
  		return -ENOENT;
  	cpu_relax();
-@@ -1376,7 +1379,7 @@ static void __queue_work(int cpu, struct
+@@ -1376,7 +1381,7 @@ static void __queue_work(int cpu, struct
  	 * queued or lose PENDING.  Grabbing PENDING and queueing should
  	 * happen with IRQ disabled.
  	 */
@@ -68,7 +70,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  
  	debug_work_activate(work);
  
-@@ -1482,14 +1485,14 @@ bool queue_work_on(int cpu, struct workq
+@@ -1482,14 +1487,14 @@ bool queue_work_on(int cpu, struct workq
  	bool ret = false;
  	unsigned long flags;
  
@@ -85,7 +87,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  	return ret;
  }
  EXPORT_SYMBOL(queue_work_on);
-@@ -1556,14 +1559,14 @@ bool queue_delayed_work_on(int cpu, stru
+@@ -1556,14 +1561,14 @@ bool queue_delayed_work_on(int cpu, stru
  	unsigned long flags;
  
  	/* read the comment in __queue_work() */
@@ -102,7 +104,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  	return ret;
  }
  EXPORT_SYMBOL(queue_delayed_work_on);
-@@ -1598,7 +1601,7 @@ bool mod_delayed_work_on(int cpu, struct
+@@ -1598,7 +1603,7 @@ bool mod_delayed_work_on(int cpu, struct
  
  	if (likely(ret >= 0)) {
  		__queue_delayed_work(cpu, wq, dwork, delay);
@@ -111,7 +113,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  	}
  
  	/* -ENOENT from try_to_grab_pending() becomes %true */
-@@ -2916,7 +2919,7 @@ static bool __cancel_work_timer(struct w
+@@ -2916,7 +2921,7 @@ static bool __cancel_work_timer(struct w
  
  	/* tell other tasks trying to grab @work to back off */
  	mark_work_canceling(work);
@@ -120,7 +122,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  
  	flush_work(work);
  	clear_work_data(work);
-@@ -2971,10 +2974,10 @@ EXPORT_SYMBOL_GPL(cancel_work_sync);
+@@ -2971,10 +2976,10 @@ EXPORT_SYMBOL_GPL(cancel_work_sync);
   */
  bool flush_delayed_work(struct delayed_work *dwork)
  {
@@ -133,12 +135,12 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  	return flush_work(&dwork->work);
  }
  EXPORT_SYMBOL(flush_delayed_work);
-@@ -3009,7 +3012,7 @@ bool cancel_delayed_work(struct delayed_
+@@ -2992,7 +2997,7 @@ static bool __cancel_work(struct work_st
+ 		return false;
  
- 	set_work_pool_and_clear_pending(&dwork->work,
- 					get_work_pool_id(&dwork->work));
+ 	set_work_pool_and_clear_pending(work, get_work_pool_id(work));
 -	local_irq_restore(flags);
 +	local_unlock_irqrestore(pendingb_lock, flags);
  	return ret;
  }
- EXPORT_SYMBOL(cancel_delayed_work);
+ 
diff --git a/patches/workqueue-use-rcu_readlock-in-put_pwq_unlocked.patch b/patches/workqueue-use-rcu_readlock-in-put_pwq_unlocked.patch
deleted file mode 100644
index 1c0ddee38c8b76..00000000000000
--- a/patches/workqueue-use-rcu_readlock-in-put_pwq_unlocked.patch
+++ /dev/null
@@ -1,49 +0,0 @@
-From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
-Date: Mon, 12 Dec 2016 16:14:18 +0100
-Subject: [PATCH] workqueue: use rcu_readlock() in put_pwq_unlocked()
-
-The RCU sched protection was changed to RCU only and so all IRQ-off and
-preempt-off disabled region were changed to the relevant rcu-read-lock
-primitives. One was missed and triggered:
-|[ BUG: bad unlock balance detected! ]
-|4.4.30-rt41 #51 Tainted: G        W
-|btattach/345 is trying to release lock (
-|Unable to handle kernel paging request at virtual address 6b6b6bbb
-|Backtrace:
-|[<c016b5a0>] (lock_release) from [<c0804844>] (rt_spin_unlock+0x20/0x30)
-|[<c0804824>] (rt_spin_unlock) from [<c0138954>] (put_pwq_unlocked+0xa4/0x118)
-|[<c01388b0>] (put_pwq_unlocked) from [<c0138b2c>] (destroy_workqueue+0x164/0x1b0)
-|[<c01389c8>] (destroy_workqueue) from [<c078e1ac>] (hci_unregister_dev+0x120/0x21c)
-|[<c078e08c>] (hci_unregister_dev) from [<c054f658>] (hci_uart_tty_close+0x90/0xbc)
-|[<c054f5c8>] (hci_uart_tty_close) from [<c03a2be8>] (tty_ldisc_close+0x50/0x58)
-|[<c03a2b98>] (tty_ldisc_close) from [<c03a2cb4>] (tty_ldisc_kill+0x18/0x78)
-|[<c03a2c9c>] (tty_ldisc_kill) from [<c03a3528>] (tty_ldisc_release+0x100/0x134)
-|[<c03a3428>] (tty_ldisc_release) from [<c039cd68>] (tty_release+0x3bc/0x460)
-|[<c039c9ac>] (tty_release) from [<c020cc08>] (__fput+0xe0/0x1b4)
-|[<c020cb28>] (__fput) from [<c020cd3c>] (____fput+0x10/0x14)
-|[<c020cd2c>] (____fput) from [<c013e0d4>] (task_work_run+0xa4/0xb8)
-|[<c013e030>] (task_work_run) from [<c0121754>] (do_exit+0x40c/0x8b0)
-|[<c0121348>] (do_exit) from [<c0122ff8>] (do_group_exit+0x54/0xc4)
-
-Cc: stable-rt@vger.kernel.org
-Reported-by: John Keeping <john@metanate.com>
-Tested-by: John Keeping <john@metanate.com>
-Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
----
- kernel/workqueue.c |    2 ++
- 1 file changed, 2 insertions(+)
-
---- a/kernel/workqueue.c
-+++ b/kernel/workqueue.c
-@@ -1104,9 +1104,11 @@ static void put_pwq_unlocked(struct pool
- 		 * As both pwqs and pools are RCU protected, the
- 		 * following lock operations are safe.
- 		 */
-+		rcu_read_lock();
- 		local_spin_lock_irq(pendingb_lock, &pwq->pool->lock);
- 		put_pwq(pwq);
- 		local_spin_unlock_irq(pendingb_lock, &pwq->pool->lock);
-+		rcu_read_unlock();
- 	}
- }
-