Re: [PATCH tty-next 17/22] tty: Remove ASYNC_CLOSING

[Jesper Nilsson]

On Mon, Jun 16, 2014 at 09:17:14AM -0400, Peter Hurley wrote:
> Since at least before 2.6.30, tty drivers that do not drop the tty lock
> while closing cannot observe ASYNC_CLOSING set while holding the
> tty lock; this includes the tty driver's open() and hangup() methods,
> since the tty core calls these methods holding the tty lock.
> 
> For these drivers, waiting for ASYNC_CLOSING to clear while opening
> is not required, since this condition cannot occur. Similarly, even
> when the open() method drops and reacquires the tty lock after
> blocking, ASYNC_CLOSING cannot be set (again, for drivers that
> do not drop the tty lock while closing).
> 
> Now that tty port drivers no longer drop the tty lock while closing
> (since 'tty: Remove tty_wait_until_sent_from_close()'), the same
> conditions apply: waiting for ASYNC_CLOSING to clear while opening
> is not required, nor is re-checking ASYNC_CLOSING after dropping and
> reacquiring the tty lock while blocking (eg., in *_block_til_ready()).
> 
> Since ASYNC_CLOSING is not tested elsewhere, it is safe to remove
> the flag.
> 
> CC: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
> CC: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
> CC: linux-s390@xxxxxxxxxxxxxxx
> CC: Mikael Starvik <starvik@xxxxxxxx>

For the CRIS part:

Acked-by: Jesper Nilsson <jesper.nilsson@xxxxxxxx>

> CC: linux-cris-kernel@xxxxxxxx
> CC: Samuel Ortiz <samuel@xxxxxxxxxx>
> CC: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Signed-off-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>

/^JN - Jesper Nilsson
-- 
               Jesper Nilsson -- jesper.nilsson@xxxxxxxx
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