On Tue, Jun 23, 2020 at 02:52:00PM -0300, Jason Gunthorpe wrote: > On Tue, Jun 23, 2020 at 02:15:31PM +0300, Leon Romanovsky wrote: > > From: Maor Gottlieb <maorg@xxxxxxxxxxxx> > > > > Replace the mutex with read write semaphore and use xarray instead > > of linked list for XRC target QPs. This will give faster XRC target > > lookup. In addition, when QP is closed, don't insert it back to the > > xarray if the destroy command failed. > > > > Signed-off-by: Maor Gottlieb <maorg@xxxxxxxxxxxx> > > Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> > > drivers/infiniband/core/verbs.c | 57 ++++++++++++--------------------- > > include/rdma/ib_verbs.h | 5 ++- > > 2 files changed, 23 insertions(+), 39 deletions(-) > > > > diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c > > index d66a0ad62077..1ccbe43e33cd 100644 > > +++ b/drivers/infiniband/core/verbs.c > > @@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context) > > spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags); > > } > > > > -static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp) > > -{ > > - mutex_lock(&xrcd->tgt_qp_mutex); > > - list_add(&qp->xrcd_list, &xrcd->tgt_qp_list); > > - mutex_unlock(&xrcd->tgt_qp_mutex); > > -} > > - > > static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp, > > void (*event_handler)(struct ib_event *, void *), > > void *qp_context) > > @@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, > > if (qp_open_attr->qp_type != IB_QPT_XRC_TGT) > > return ERR_PTR(-EINVAL); > > > > - qp = ERR_PTR(-EINVAL); > > - mutex_lock(&xrcd->tgt_qp_mutex); > > - list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) { > > - if (real_qp->qp_num == qp_open_attr->qp_num) { > > - qp = __ib_open_qp(real_qp, qp_open_attr->event_handler, > > - qp_open_attr->qp_context); > > - break; > > - } > > + down_read(&xrcd->tgt_qps_rwsem); > > + real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num); > > + if (!real_qp) { > > Don't we already have a xarray indexed against qp_num in res_track? > Can we use it somehow? We don't have restrack for XRC, we will need somehow manage QP-to-XRC connection there. Thanks > > Jason