dbb92f8864
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>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.