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?
Jason
