IB/ipath: Limit # of packets sent without an ACK received
The sender requests an ACK every 1/2 MB to avoid retransmit timeouts that
were causing MVAPICH mod_bw to fail after a predictable number of sends.
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/ipath/ipath_verbs.h b/drivers/infiniband/hw/ipath/ipath_verbs.h
index 09bbb3f..3fffaa0 100644
--- a/drivers/infiniband/hw/ipath/ipath_verbs.h
+++ b/drivers/infiniband/hw/ipath/ipath_verbs.h
@@ -370,6 +370,7 @@
u8 s_rnr_retry_cnt;
u8 s_retry; /* requester retry counter */
u8 s_rnr_retry; /* requester RNR retry counter */
+ u8 s_wait_credit; /* limit number of unacked packets sent */
u8 s_pkey_index; /* PKEY index to use */
u8 timeout; /* Timeout for this QP */
enum ib_mtu path_mtu;
@@ -393,6 +394,8 @@
#define IPATH_S_BUSY 0
#define IPATH_S_SIGNAL_REQ_WR 1
+#define IPATH_PSN_CREDIT 2048
+
/*
* Since struct ipath_swqe is not a fixed size, we can't simply index into
* struct ipath_qp.s_wq. This function does the array index computation.
@@ -521,6 +524,7 @@
u32 n_rnr_naks;
u32 n_other_naks;
u32 n_timeouts;
+ u32 n_rc_stalls;
u32 n_pkt_drops;
u32 n_vl15_dropped;
u32 n_wqe_errs;