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From: Arnd Bergmann <arnd@arndb.de>
To: "Daniel K." <dk@uw.no>
Subject: Re: [PATCH 10/10] tty: implement BTM as mutex instead of BKL
Date: Sun, 16 May 2010 14:58:37 +0200
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On Sunday 16 May 2010 05:33:14 Daniel K. wrote:
> Arnd Bergmann wrote:
> > diff --git a/drivers/char/tty_mutex.c b/drivers/char/tty_mutex.c
> > new file mode 100644
> > index 0000000..f66dfdf
> > --- /dev/null
> > +++ b/drivers/char/tty_mutex.c
> > @@ -0,0 +1,47 @@
> > +/*
> > + * drivers/char/tty_lock.c
> > + */
> > +#include <linux/tty.h>
> > +#include <linux/module.h>
> > +#include <linux/kallsyms.h>
> > +#include <linux/semaphore.h>
> > +#include <linux/sched.h>
> > +
> > +/*
> > + * The 'big tty semaphore'
> 
> Referred to as Big TTY Mutex or BTM elsewhere.
> 
> 
> > + * This mutex is taken and released by tty_lock() and tty_unlock(),
> > + * replacing the older big kernel mutex.
> 
> big kernel lock, or BKL?
> 

Thanks for looking at this, this (and the bug you found in amiserial)
were caused by changing it a few times from one implementation to the next.

Fixed now and pushed out to git.

	Anrd