[PATCH v2 02/11] common: introduce bthreads, co-operative barebox threads

[Peter Korsgaard]

>>>>> "Ahmad" == Ahmad Fatoum <a.fatoum at pengutronix.de> writes:

Hi,
 
 > +bthreads
 > +--------
 > +
 > +barebox threads are co-operative green threads, which are scheduled whenever
 > +``is_timeout()`` is called.  This has a few implications. First of all,
 > +bthreads are not scheduled when ``is_timeout()`` is not called.
 > +For this and other reasons, loops polling for hardware events should always
 > +use a timeout, which is best implemented with ``is_timeout()``.
 > +Another thing to remember is that bthreads can be scheduled anywhere
 > +in the middle of other device accesses whenever ``is_timeout()`` is
 > +called. Care must be taken that a green thread doesn't access the very same device
 > +again itself. See "slices" below on how devices can safely be accessed from
 > +bthreads.
 > +
 > +Unlike pollers, which bthreads are replacing, bthreads are allowed
 > +access to virtual filesystem. The macro ``assert_command_context()`` is added
 > +to entry points of the VFS to have the thread yield until it may execute in
 > +in the correct context. The poller interface is declared in

s/poller/bthread/

 > +``include/bthread.h``.  ``bthread_create()`` is used to allocate a bthread
 > +control block along with its stack. ``bthread_wake()`` can be used to hang
 > +it into the run queue. From this moment on and until the thread terminates,

s/hang it into/add/

 > +the thread will be switched to regularly as long as someone calls
 > +``is_timeout()``. bthreads are allowed to call ``is_timeout()``, which will
 > +arrange for other threads to execute.
 > +
 > +barebox threads replace previous the previous pollers and workqueues. Poller

s/previous the previous/the previous infrastructure,/

-- 
Bye, Peter Korsgaard