Files
kernel/include/linux
Andrea Parri dbb92f8864 workqueue: Document (some) memory-ordering properties of {queue,schedule}_work()
It's desirable to be able to rely on the following property:  All stores
preceding (in program order) a call to a successful queue_work() will be
visible from the CPU which will execute the queued work by the time such
work executes, e.g.,

  { x is initially 0 }

    CPU0                              CPU1

    WRITE_ONCE(x, 1);                 [ "work" is being executed ]
    r0 = queue_work(wq, work);          r1 = READ_ONCE(x);

  Forbids: r0 == true && r1 == 0

The current implementation of queue_work() provides such memory-ordering
property:

  - In __queue_work(), the ->lock spinlock is acquired.

  - On the other side, in worker_thread(), this same ->lock is held
    when dequeueing work.

So the locking ordering makes things work out.

Add this property to the DocBook headers of {queue,schedule}_work().

Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2020-02-12 15:59:40 -05:00
..
2020-01-27 14:35:32 +01:00
2020-01-23 12:37:18 +00:00
2020-02-04 03:05:26 +00:00
2020-02-04 03:05:26 +00:00
2020-01-23 00:35:50 +01:00
2020-01-27 11:09:31 +01:00
2020-01-17 16:48:07 -08:00
2020-01-18 09:19:18 -05:00
2020-01-13 21:48:42 +01:00
2020-01-31 17:33:54 +00:00
2020-02-04 07:24:48 +00:00
2020-01-15 10:54:33 -05:00
2020-01-14 12:20:48 +01:00
2020-01-16 17:09:18 +01:00
2020-01-15 16:30:28 +00:00
2020-01-29 17:00:02 -06:00
2020-01-13 18:16:43 -08:00
2020-01-10 14:00:58 -08:00
2020-01-24 10:24:31 -08:00
2020-01-24 10:24:31 -08:00
2020-02-04 03:05:24 +00:00
2020-01-13 18:31:48 -08:00
2020-02-04 03:05:26 +00:00
2020-01-14 12:20:48 +01:00
2020-01-17 22:33:37 -05:00