Re: [PATCH 0/6] Shrinking DT memory usage

From: Nicolas Pitre
Date: Fri Oct 06 2017 - 17:30:46 EST


On Thu, 5 Oct 2017, Rob Herring wrote:

> On kernels with a minimal config and a RAM target in the 100s of KB, DT
> is quite a hog of runtime memory usage. How much is dependent on how many
> nodes and properties in the DT which have a corresponding struct device_node
> and struct property in the kernel. Just skipping disabled nodes saves a
> lot by not creating the device_nodes in the first place[1], but there's
> more low hanging fruit by making some of the fields in struct property and
> struct device_node optional. With the changes here, the memory usage goes
> from 17KB to under 8KB on QEMU's ARM virt machine which is a relatively
> small DT.

My test case went from 118072 bytes ddown to 21548 bytes with this
series.

Tested-by: Nicolas Pitre <nico@xxxxxxxxxx>


Nicolas