[RFC PATCH] dt:numa: adding numa node mapping for memory nodes.
From: Nathan Lynch <hidden>
Date: 2014-09-17 21:48:39
Also in:
linux-devicetree
Possibly related (same subject, not in this thread)
- 2014-10-28 · Re: [RFC PATCH] dt:numa: adding numa node mapping for memory nodes. · Hanjun Guo <hidden>
- 2014-10-28 · Re: [RFC PATCH] dt:numa: adding numa node mapping for memory nodes. · Hanjun Guo <hidden>
- 2014-09-18 · Re: [RFC PATCH] dt:numa: adding numa node mapping for memory nodes. · Ganapatrao Kulkarni <hidden>
- 2014-09-18 · Re: [RFC PATCH] dt:numa: adding numa node mapping for memory nodes. · Ganapatrao Kulkarni <hidden>
- 2014-09-17 · Re: [RFC PATCH] dt:numa: adding numa node mapping for memory nodes. · Zi Shen Lim <hidden>
On 09/17/2014 03:56 AM, Ganapatrao Kulkarni wrote:
quoted hunk
From: Ganapatrao Kulkarni <redacted> This patch adds property "nid" to memory node to provide the memory range to numa node id mapping. Signed-off-by: Ganapatrao Kulkarni <redacted> --- Documentation/devicetree/bindings/numa.txt | 58 ++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 Documentation/devicetree/bindings/numa.txtdiff --git a/Documentation/devicetree/bindings/numa.txt b/Documentation/devicetree/bindings/numa.txt new file mode 100644 index 0000000..c4a94f2 --- /dev/null +++ b/Documentation/devicetree/bindings/numa.txt@@ -0,0 +1,58 @@ +====================================================== +numa id binding description +====================================================== + +====================================================== +1 - Introduction +====================================================== +The device node property "nid(numa node id)" can be added to memory +device node to map the range of memory addresses as defined in property "reg". +The property "nid" maps the memory range to the numa node id, which is used to +find the local and remory pages on numa aware systems.
"Local" and "remote" memory are notions that relate to some other resource -- typically a CPU, but also I/O resources on some systems. It seems to me that a useful NUMA binding would at least specify a "nid" property, or something like it, for both cpu and memory nodes. But this document speaks only of memory nodes. As Kumar said, the device tree on powerpc server systems already has properties that express NUMA information. If you can get hold of a copy of the PAPR (not ePAPR) from power.org, refer to the description of "ibm,associativity" and related properties. I recall that it's a bit more complex than this proposal, though.