Re: [PATCH] USB: ftdi_sio: Remove tty->low_latency.

From: Oliver Neukum
Date: Sat Oct 03 2009 - 09:26:09 EST


Am Samstag, 3. Oktober 2009 15:18:07 schrieb Alan Cox:
> The generic driver is a very bad example to follow in some areas but
> this looks a big improvement. There are some patches reworking the
> generic code to use kfifo on the output side which make it vastly better.
> Not sure where the relevant google submissions went ?

They have been included into rc1.

> > -     spin_lock_irqsave(&priv->rx_lock, flags);
> > -     priv->rx_flags &= ~(THROTTLED | ACTUALLY_THROTTLED);
> > -     spin_unlock_irqrestore(&priv->rx_lock, flags);
> > +     spin_lock_irqsave(&port->lock, flags);
> > +     port->throttled = 0;
> > +     spin_unlock_irqrestore(&port->lock, flags);
>
> If you only have a single bit use the set_bit/clear_bit/test_and_xxx_bit
> stuff as it's faster on most boxes

I think we cannot do with less than two flags, whose transition has
to be atomic here.

Regards
Oliver

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