Re: [PATCH wq/for-3.19 3/3] workqueue: dump workqueues on sysrq-t

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, Dec 08, 2014 at 02:22:29PM -0500, Tejun Heo wrote:
> (cc'ing Greg for tty)
> 
> On Mon, Dec 08, 2014 at 11:05:15AM -0800, Andrew Morton wrote:
> > > Believe it or not, we already used up all alphanumerics if we count in
> > > the arch-specific ones.  Given that the workqueue information would
> > > primarily be useful in tracking down hangs and we'd want to see the
> > > dump of tasks in that case anyway, sysrq-t isn't a bad fit for
> > > appending workqueue dump.  If anybody has a better idea, I'm all ears.
> > 
> > Really.  Upper case?
> 
> Greg, would using uppercase chars for sysrq work over the different
> types of ttys?

I'm dragging in linux-serial@vger here also, but I think uppercase
characters will work from a tty standpoint.  I don't know about keyboard
scancodes, if they will do "odd" things wanting a shift with the sysrq
key at the same time.

Oh wait, I think that might be it, shift is needed for the sysrq key on
the keyboard to start with, right?  So there probably isn't a way to
test the difference of a lower/upper case key here.

I'm traveling this week, and don't have access to a "real" keyboard at
the moment, but this should be pretty easy for someone to test who has
one and cares about this type of thing {hint}.

thanks,

greg k-h