On Thu, Jan 21, 2021 at 09:50:03AM -0800, Manjunath Patil wrote: > ipoib connected mode presently queries the device[HCA] to get P_Key > table entry during connection formation. This will increase the time > taken to form the connection, especially when limited P_Keys are in use. > This gets worse when multiple connection attempts are done in parallel. > Improve this by using the cached version of ib_find_pkey(). > > This improved the latency from 500ms to 3ms on an internal setup. > > Suggested-by: Haakon Bugge <haakon.bugge@xxxxxxxxxx> > Signed-off-by: Manjunath Patil <manjunath.b.patil@xxxxxxxxxx> > drivers/infiniband/ulp/ipoib/ipoib_cm.c | 4 +++- > 1 files changed, 3 insertions(+), 1 deletions(-) > > diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c > index 8f0b598..013a1d8 100644 > +++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c > @@ -40,6 +40,7 @@ > #include <linux/moduleparam.h> > #include <linux/sched/signal.h> > #include <linux/sched/mm.h> > +#include <rdma/ib_cache.h> > > #include "ipoib.h" > > @@ -1122,7 +1123,8 @@ static int ipoib_cm_modify_tx_init(struct net_device *dev, > struct ipoib_dev_priv *priv = ipoib_priv(dev); > struct ib_qp_attr qp_attr; > int qp_attr_mask, ret; > - ret = ib_find_pkey(priv->ca, priv->port, priv->pkey, &qp_attr.pkey_index); > + ret = ib_find_cached_pkey(priv->ca, priv->port, priv->pkey, > + &qp_attr.pkey_index); ipoib interfaces are locked to a single pkey, you should be able to get the pkey index that was determined at link up time and use it here instead of searching anything Jason
