Messages in this thread | | | Subject | Re: [RFC][PATCH 7/7] serial, 8250: Mostly avoid wakeups from under port->lock | From | Peter Zijlstra <> | Date | Wed, 21 Dec 2011 17:22:34 +0100 |
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On Wed, 2011-12-21 at 16:03 +0000, Alan Cox wrote:
> > + BUG_ON(!state); > > + tty = state->port.tty; > > + tty_kref_get(tty); > > + spin_unlock_irqrestore(&up->port.lock, flags); > > + tty_wakeup(tty); > > + tty_kref_put(tty); > > driver innards shouldn't know this stuff and this makes it worse rather > than cleaning it up
Fair enough, if I can push it into serial_core.c I can probably fix that one weird case as well, I couldn't inside the 8250 driver because the port lock was taken by the serial core code.
> The basic idea looks fine but I really don't want magic lock hackery in > the 8250 driver. We need a way of generalising this so the code is > cleaner and the locking internal knowledge stays out of the driver itself. > > Also I think it's probably buggy - sending the x_char is forward progress > so probably needs to cause a wakeup.
Could you explain that more, its not actually connecting with any neurons..
> So for the moment NAK, but worthy of figuring out how to do it right
OK, will try and see if I can poke at it a level upwards..
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