Messages in this thread | | | Date | Tue, 20 Nov 2012 14:25:50 -0800 | From | Andrew Morton <> | Subject | Re: [PART4 Patch v2 1/2] numa: add CONFIG_MOVABLE_NODE for movable-dedicated node |
| |
On Fri, 16 Nov 2012 19:58:09 +0800 Wen Congyang <wency@cn.fujitsu.com> wrote:
> From: Lai Jiangshan <laijs@cn.fujitsu.com> > > All are prepared, we can actually introduce N_MEMORY. > add CONFIG_MOVABLE_NODE make we can use it for movable-dedicated node
This description is far too short on details.
I grabbed this from the [0/n] email:
: We need a node which only contains movable memory. This feature is very : important for node hotplug. If a node has normal/highmem, the memory may : be used by the kernel and can't be offlined. If the node only contains : movable memory, we can offline the memory and the node.
which helps a bit, but it's still pretty thin.
Why is this option made configurable? Why not enable it unconditionally?
Please send a patch which adds the Kconfig help text for CONFIG_MOVABLE_NODE. Let's make that text nice and detailed.
The name MOVABLE_NODE is not a good one. It means "a node which is movable", whereas the concept is actually "a node whcih contains only movable memory". I suppose we could change it to something like CONFIG_MOVABLE_MEMORY_ONLY_NODE or similar. But I suppose that CONFIG_MOVABLE_NODE is good enough, as long as it is well-described in associated comments or help text. This is not the case at present.
> +#ifdef CONFIG_MOVABLE_NODE > + N_MEMORY, /* The node has memory(regular, high, movable) */ > +#else
I think the comment should be "The node has only movable memory"?
| |