On Tue, May 01, 2018 at 04:55:05PM -0500, Rohit Zambre wrote: > On Mon, Apr 30, 2018 at 1:38 PM, Jason Gunthorpe <jgg@xxxxxxxxxxxx> wrote: > > > > On Fri, Apr 27, 2018 at 04:36:15AM +0000, Rohit Zambre wrote: > > > By creating a QP within a thread domain the application is guaranteeing > > > that the QP will not be accessed concurrently from multiple user threads. > > > Hence, a lock is not needed for QP that is assigned to a thread domain. > > > > > > This patch disables locking on the QP if a thread domain is passed during > > > QP-creation. > > > > > > Signed-off-by: Rohit Zambre <rzambre@xxxxxxx> > > > providers/mlx5/verbs.c | 12 +++++++++--- > > > 1 file changed, 9 insertions(+), 3 deletions(-) > > > > > > diff --git a/providers/mlx5/verbs.c b/providers/mlx5/verbs.c > > > index 9fd765e..f7132e4 100644 > > > +++ b/providers/mlx5/verbs.c > > > @@ -1607,6 +1607,7 @@ static struct ibv_qp *create_qp(struct ibv_context *context, > > > struct mlx5_create_qp_ex_resp resp_ex; > > > struct mlx5_qp *qp; > > > int ret; > > > + int thread_safe; > > > struct mlx5_context *ctx = to_mctx(context); > > > struct ibv_qp *ibqp; > > > int32_t usr_idx = 0; > > > @@ -1751,8 +1752,14 @@ static struct ibv_qp *create_qp(struct ibv_context *context, > > > > > > mlx5_init_qp_indices(qp); > > > > > > - if (mlx5_spinlock_init(&qp->sq.lock, !mlx5_single_threaded) || > > > - mlx5_spinlock_init(&qp->rq.lock, !mlx5_single_threaded)) > > > + mparent_domain = to_mparent_domain(attr->pd); > > > + if (mparent_domain && mparent_domain->mtd) > > > + thread_safe = 1; > > > + else > > > + thread_safe = mlx5_single_threaded; > > > + > > > + if (mlx5_spinlock_init(&qp->sq.lock, !thread_safe) || > > > + mlx5_spinlock_init(&qp->rq.lock, !thread_safe)) > > > goto err_free_qp_buf; > > > > This would be nicer to have a 'mlx5_spinlock_init_pd' that takes the > > object's pd and does the above calcuations. > > > > All the remaining uses should be revised at once to use a pd if it > > makes sense during the init.. > > Makes sense. Are you referring to the Parent Domain or the Protection > Domain by PD here? If I recall, at this layer they are still interchangable. The 'mlx5_spinlock_init_pd' should determine if the ibv_pd is a parent domain, then determine if it specifies single threaded operation. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
