Re: [ANNOUNCE] [PATCH] Node Hotplug Support

[Dave Hansen <haveblue@us.ibm.com>]

On Wed, 2004-05-12 at 18:27, Keiichiro Tokunaga wrote:
> On Sun, 09 May 2004 22:45:42 -0700
> Dave Hansen <haveblue@us.ibm.com> wrote:
> 
> > On Sun, 2004-05-09 at 18:47, Keiichiro Tokunaga wrote:
> > > There is no NUMA support in the current code yet.  I'll post a
> > > rough patch to show my idea soon.  I'm thinking to regard a
> > > container device that has PXM as a NUMA node so far.
> > 
> > Don't you think it would be a good idea to work with some of the current
> > code, instead of trying to wrap around it?  
> 
> Are you saying that LHNS should use the current NUMA code
> (or coming code in the future) to support NUMA node hotplug?

Absolutely.  Why do we need wrappers when we can offline entire nodes
with 6-line shell scripts?  The CPU hotplug interfaces are here today
and the memory stuff will be here soon.  Perhaps you could help with the
NUMA part.

#!/bin/sh
NODENUM=$1
NODEDIR=/sys/devices/system/node/node${NODENUM}
for i in $NODEDIR/cpu* $NODEDIR/memory*; do
	echo 0 > $i/control/online
fi
echo 0 > $NODEDIR/control/online

We don't currently export bus to node mappings in sysfs, but we have
them in the kernel, so that won't be too hard to export as well.  

-- Dave