From b1812582ba94b5f377d5d3cec7646cc17d84e733 Mon Sep 17 00:00:00 2001 From: Joachim Fenkes Date: Fri, 30 Nov 2007 16:19:41 -0800 Subject: 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 Signed-off-by: Roland Dreier --- drivers/infiniband/hw/ehca/ehca_av.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'drivers/infiniband/hw/ehca') diff --git a/drivers/infiniband/hw/ehca/ehca_av.c b/drivers/infiniband/hw/ehca/ehca_av.c index 453eb995c1d4..f7782c882ab4 100644 --- a/drivers/infiniband/hw/ehca/ehca_av.c +++ b/drivers/infiniband/hw/ehca/ehca_av.c @@ -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; } -- cgit v1.2.3-59-g8ed1b