On Fri, 2009-10-16 at 10:33 -0500, Scott Wood wrote: > On Fri, Oct 16, 2009 at 03:46:45PM +1100, Benjamin Herrenschmidt wrote: > > On Thu, 2009-10-15 at 13:57 -0500, Scott Wood wrote: > > > I'd say the dropping approach is quite undesirable (significant > > > potential for output loss unless the buffer is huge), unless there's > > > simply no way to safely spin. Hopefully there are no such backends, but > > > if there are perhaps we can have them return some special code to > > > indicate that. > > > > Should never spin. > > Why is a hypervisor console different than a serial port in this regard?
Ah sorry, yeah, struct console can I suppose, it's the tty that shouldn't. > > Best is to keep a copy in the upper layer of the pending data and throttle > > (not accept further data from tty layer) until we have managed to flush > > out that "pending" buffer. > > The data isn't coming from the tty layer -- we're talking about printk. How > do you throttle that without spinning? > > I agree that it shouldn't spin when handling tty I/O. Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
