[v9,6/6] docs: mm: numaperf.rst Add brief description for access class 1.

Commit Message

Jonathan Cameron Aug. 19, 2020, 2:51 p.m. UTC

Try to make minimal changes to the document which already describes
access class 0 in a generic fashion (including IO initiatiors that
are not CPUs).

Signed-off-by: Jonathan Cameron <[e-mail]>
---
 Documentation/admin-guide/mm/numaperf.rst | 8 ++++++++
 1 file changed, 8 insertions(+)

Patch

diff --git a/Documentation/admin-guide/mm/numaperf.rst b/Documentation/admin-guide/mm/numaperf.rst
index 4d69ef1de830..b89bb85eac75 100644
--- a/Documentation/admin-guide/mm/numaperf.rst
+++ b/Documentation/admin-guide/mm/numaperf.rst
@@ -56,6 +56,11 @@  nodes' access characteristics share the same performance relative to other
 linked initiator nodes. Each target within an initiator's access class,
 though, do not necessarily perform the same as each other.
 
+The access class "1" is used to allow differentiation between initiators
+that are CPUs and hence suitable for generic task scheduling, and
+IO initiators such as GPUs and NICs.  Unlike access class 0, only
+nodes containing CPUs are considered.
+
 ================
 NUMA Performance
 ================
@@ -88,6 +93,9 @@  The latency attributes are provided in nanoseconds.
 The values reported here correspond to the rated latency and bandwidth
 for the platform.
 
+Access class 1, takes the same form, but only includes values for CPU to
+memory activity.
+
 ==========
 NUMA Cache
 ==========