IB/ehca: Fix static rate if path faster than link
The formula would yield -1 if the path is faster than the link, which
is wrong in a bad way (max throttling). Clamp to 0, which is the
correct value.
Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/ehca/ehca_av.c b/drivers/infiniband/hw/ehca/ehca_av.c
index 453eb99..f7782c8 100644
--- a/drivers/infiniband/hw/ehca/ehca_av.c
+++ b/drivers/infiniband/hw/ehca/ehca_av.c
@@ -76,8 +76,12 @@
link = ib_width_enum_to_int(pa.active_width) * pa.active_speed;
- /* IPD = round((link / path) - 1) */
- *ipd = ((link + (path >> 1)) / path) - 1;
+ if (path >= link)
+ /* no need to throttle if path faster than link */
+ *ipd = 0;
+ else
+ /* IPD = round((link / path) - 1) */
+ *ipd = ((link + (path >> 1)) / path) - 1;
return 0;
}