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>
This commit is contained in:
Joachim Fenkes 2007-11-30 16:19:41 -08:00 committed by Roland Dreier
parent 1401b53acc
commit b1812582ba
1 changed files with 6 additions and 2 deletions

View File

@ -76,8 +76,12 @@ int ehca_calc_ipd(struct ehca_shca *shca, int port,
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;
}