Re: [RFC] Change locking in block_dev.c:do_open()

["David C. Hansen" <dave@sr71.net>]

Ryan Cumming wrote:
> On December 12, 2001 16:39, David C. Hansen wrote:
> > We can add a semaphore which must be acquired before a module can be
> > unloaded, and hold it over the area where the module must not be
> > unloaded.  We could replace the unload_lock spinlock with a semaphore,
> > which I'll call it unload_sem here.  It would look something like this:
> Why not use a read-write semaphore? The sections that require the module to
> stay resident use a read lock, and module unloading aquires a write lock. In
> addition to containing the evil, evil BKL, you might actually get a tangiable
> scalability gain out of it.
Cool idea.  I'll do that.  Now that we have those locking primitives in
the kernel I wish that we used them more often. 
-- 
David C. Hansen
dave@sr71.net