dea9c80ee6
The read_lock mutex is supposed to prevent collisions between reading and writing to the line event kfifo but it's actually only taken when the events are being read from it. Drop the mutex entirely and reuse the spinlock made available to us in the waitqueue struct. Take the lock whenever the fifo is modified or inspected. Drop the call to kfifo_to_user() and instead first extract the new element from kfifo when the lock is taken and only then pass it on to the user after the spinlock is released. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
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.