pseries/memory-hotplug: Only update DT once per memory DLPAR request

[Michael Ellerman]

On Fri, 2018-04-20 at 20:29:48 UTC, Nathan Fontenot wrote:
> The updates to powerpc numa and memory hotplug code now use the
> in-kernel LMB array instead of the device tree. This change
> allows the pseries memory DLPAR code to only update the device
> tree once after successfully handling a DLPAR request.
> 
> Prior to the in-kernel LMB array, the numa code looked up the
> affinity for memory being added in the device tree, the code
> now looks this up in the LMB array. This change means the
> memory hotplug code can just update the affinity for an LMB
> in the LMB array instead of updating the device tree.
> 
> This also provides a savings in kernel memory. When updating the
> device tree old properties are never free'ed since there is no
> usecount on properties. This behavior leads to a new copy of the
> property being allocated every time a LMB is added or removed
> (i.e. a request to add 100 LMBs creates 100 new copies of the
> property). With this update only a single new property is created
> when a DLPAR request completes successfully.
> 
> Signed-off-by: Nathan Fontenot <nfont at linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/063b8b1251fd069f3740339fca5611

cheers