[ofa-general] [PATCH] Clarify the syntax of the hop_weights_file

[Jason Gunthorpe]

- GUID is a port guid, and is specified in hex with 0x prefix
- Lines with # are comments
- Weights are simplex not duplex.
---
 opensm/man/opensm.8.in |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

I met some people who were trying to use this and we had to look
through the source to figure it out.

diff --git a/opensm/man/opensm.8.in b/opensm/man/opensm.8.in
index 66d2fe6..dbf4b73 100644
--- a/opensm/man/opensm.8.in
+++ b/opensm/man/opensm.8.in
@@ -247,10 +247,15 @@ This option provides the means to define a set of ports
 equalization algorithm.
 .TP
 \fB\-w\fR, \fB\-\-hop_weights_file\fR <path to file>
-This option provides weighting factors per port representing a hop
-cost in computing the lid matrix.  The file consists of lines
-containing a switch GUID, output port, and weighting factor.  Any port
-not listed in the file defaults to a weighting factor of 1.
+
+This option provides weighting factors per port representing a hop cost in
+computing the lid matrix.  The file consists of lines containing a switch port
+GUID (specified as a 64 bit hex number, with leading 0x), output port number,
+and weighting factor.  Any port not listed in the file defaults to a weighting
+factor of 1.  Lines starting with # are comments.  Weights affect only the
+output route from the port, so many useful configurations will require weights
+to be specified in pairs.
+
 .TP
 \fB\-x\fR, \fB\-\-honor_guid2lid\fR
 This option forces OpenSM to honor the guid2lid file,
-- 
1.5.4.2