RDMA/mlx5: Support real-time timestamp directly from the device

Currently, if the user asks for a real-time timestamp, the device will
return a free-running one, and the timestamp will be translated to
real-time in the user-space.

When the device supports only real-time timestamp and not free-running,
the creation of the QP will fail even though the user needs supported the
real-time one. To prevent this, we will return the real-time timestamp
directly from the device.

Link: https://lore.kernel.org/r/c6cfc8e6f038575c5c2de6505830f7e74e4de80d.1623829775.git.leonro@nvidia.com
Signed-off-by: Aharon Landau <aharonl@nvidia.com>
Reviewed-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/infiniband/hw/mlx5/cq.c b/drivers/infiniband/hw/mlx5/cq.c
index 9ce01f729673918eef2a53697800f12a55ece8ef..d130fc71c3959288e03e6b1e80a0769d6fe4c431 100644 (file)
--- a/drivers/infiniband/hw/mlx5/cq.c
+++ b/drivers/infiniband/hw/mlx5/cq.c
@@ -725,7 +725,8 @@ static int create_cq_user(struct mlx5_ib_dev *dev, struct ib_udata *udata,
                return -EFAULT;
 
        if ((ucmd.flags & ~(MLX5_IB_CREATE_CQ_FLAGS_CQE_128B_PAD |
-                           MLX5_IB_CREATE_CQ_FLAGS_UAR_PAGE_INDEX)))
+                           MLX5_IB_CREATE_CQ_FLAGS_UAR_PAGE_INDEX |
+                           MLX5_IB_CREATE_CQ_FLAGS_REAL_TIME_TS)))
                return -EINVAL;
 
        if ((ucmd.cqe_size != 64 && ucmd.cqe_size != 128) ||
@@ -826,6 +827,9 @@ static int create_cq_user(struct mlx5_ib_dev *dev, struct ib_udata *udata,
                cq->private_flags |= MLX5_IB_CQ_PR_FLAGS_CQE_128_PAD;
        }
 
+       if (ucmd.flags & MLX5_IB_CREATE_CQ_FLAGS_REAL_TIME_TS)
+               cq->private_flags |= MLX5_IB_CQ_PR_FLAGS_REAL_TIME_TS;
+
        MLX5_SET(create_cq_in, *cqb, uid, context->devx_uid);
        return 0;
 

diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 644d5d0ac54428728a3d05c21b3af9c9ca17f543..a273cbb9369f853bcd3930dc2e3e74c613f0e3f7 100644 (file)
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -1816,6 +1816,12 @@ static int set_ucontext_resp(struct ib_ucontext *uctx,
        if (MLX5_CAP_GEN(dev->mdev, ece_support))
                resp->comp_mask |= MLX5_IB_ALLOC_UCONTEXT_RESP_MASK_ECE;
 
+       if (rt_supported(MLX5_CAP_GEN(dev->mdev, sq_ts_format)) &&
+           rt_supported(MLX5_CAP_GEN(dev->mdev, rq_ts_format)) &&
+           rt_supported(MLX5_CAP_ROCE(dev->mdev, qp_ts_format)))
+               resp->comp_mask |=
+                       MLX5_IB_ALLOC_UCONTEXT_RESP_MASK_REAL_TIME_TS;
+
        resp->num_dyn_bfregs = bfregi->num_dyn_bfregs;
        return 0;
 }

diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index e9a3f34a30b8f26344e3553f7e973959e95c0f74..a69874784387df2750f5be558f8045133890dd75 100644 (file)
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -550,6 +550,7 @@ static inline const struct mlx5_umr_wr *umr_wr(const struct ib_send_wr *wr)
 
 enum mlx5_ib_cq_pr_flags {
        MLX5_IB_CQ_PR_FLAGS_CQE_128_PAD = 1 << 0,
+       MLX5_IB_CQ_PR_FLAGS_REAL_TIME_TS = 1 << 1,
 };
 
 struct mlx5_ib_cq {
@@ -1614,4 +1615,10 @@ static inline bool mlx5_ib_lag_should_assign_affinity(struct mlx5_ib_dev *dev)
                (MLX5_CAP_GEN(dev->mdev, num_lag_ports) > 1 &&
                 MLX5_CAP_GEN(dev->mdev, lag_tx_port_affinity));
 }
+
+static inline bool rt_supported(int ts_cap)
+{
+       return ts_cap == MLX5_TIMESTAMP_FORMAT_CAP_REAL_TIME ||
+              ts_cap == MLX5_TIMESTAMP_FORMAT_CAP_FREE_RUNNING_AND_REAL_TIME;
+}
 #endif /* MLX5_IB_H */

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index 0e3babac62db63c353f94beed08c5f884fefd5f2..737b1f6eba0bc09c5d7375e9d6d61fc25b955feb 100644 (file)
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -1180,8 +1180,16 @@ static bool fr_supported(int ts_cap)
 }
 
 static int get_ts_format(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *cq,
-                        bool fr_sup)
+                        bool fr_sup, bool rt_sup)
 {
+       if (cq->private_flags & MLX5_IB_CQ_PR_FLAGS_REAL_TIME_TS) {
+               if (!rt_sup) {
+                       mlx5_ib_dbg(dev,
+                                   "Real time TS format is not supported\n");
+                       return -EOPNOTSUPP;
+               }
+               return MLX5_TIMESTAMP_FORMAT_REAL_TIME;
+       }
        if (cq->create_flags & IB_UVERBS_CQ_FLAGS_TIMESTAMP_COMPLETION) {
                if (!fr_sup) {
                        mlx5_ib_dbg(dev,
@@ -1198,14 +1206,16 @@ static int get_rq_ts_format(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *recv_cq)
 {
        u8 ts_cap = MLX5_CAP_GEN(dev->mdev, rq_ts_format);
 
-       return get_ts_format(dev, recv_cq, fr_supported(ts_cap));
+       return get_ts_format(dev, recv_cq, fr_supported(ts_cap),
+                            rt_supported(ts_cap));
 }
 
 static int get_sq_ts_format(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *send_cq)
 {
        u8 ts_cap = MLX5_CAP_GEN(dev->mdev, sq_ts_format);
 
-       return get_ts_format(dev, send_cq, fr_supported(ts_cap));
+       return get_ts_format(dev, send_cq, fr_supported(ts_cap),
+                            rt_supported(ts_cap));
 }
 
 static int get_qp_ts_format(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *send_cq,
@@ -1213,18 +1223,28 @@ static int get_qp_ts_format(struct mlx5_ib_dev *dev, struct mlx5_ib_cq *send_cq,
 {
        u8 ts_cap = MLX5_CAP_ROCE(dev->mdev, qp_ts_format);
        bool fr_sup = fr_supported(ts_cap);
+       bool rt_sup = rt_supported(ts_cap);
        u8 default_ts = fr_sup ? MLX5_TIMESTAMP_FORMAT_FREE_RUNNING :
                                 MLX5_TIMESTAMP_FORMAT_DEFAULT;
        int send_ts_format =
-               send_cq ? get_ts_format(dev, send_cq, fr_sup) :
+               send_cq ? get_ts_format(dev, send_cq, fr_sup, rt_sup) :
                          default_ts;
        int recv_ts_format =
-               recv_cq ? get_ts_format(dev, recv_cq, fr_sup) :
+               recv_cq ? get_ts_format(dev, recv_cq, fr_sup, rt_sup) :
                          default_ts;
 
        if (send_ts_format < 0 || recv_ts_format < 0)
                return -EOPNOTSUPP;
 
+       if (send_ts_format != MLX5_TIMESTAMP_FORMAT_DEFAULT &&
+           recv_ts_format != MLX5_TIMESTAMP_FORMAT_DEFAULT &&
+           send_ts_format != recv_ts_format) {
+               mlx5_ib_dbg(
+                       dev,
+                       "The send ts_format does not match the receive ts_format\n");
+               return -EOPNOTSUPP;
+       }
+
        return send_ts_format == default_ts ? recv_ts_format : send_ts_format;
 }
 

diff --git a/include/uapi/rdma/mlx5-abi.h b/include/uapi/rdma/mlx5-abi.h
index 27905a0268c9f286f383f17af19b36bb8989727d..82e3bc1eb57dfd2d8c18b234a3fda580716a3207 100644 (file)
--- a/include/uapi/rdma/mlx5-abi.h
+++ b/include/uapi/rdma/mlx5-abi.h
@@ -101,6 +101,7 @@ enum mlx5_ib_alloc_ucontext_resp_mask {
        MLX5_IB_ALLOC_UCONTEXT_RESP_MASK_CORE_CLOCK_OFFSET = 1UL << 0,
        MLX5_IB_ALLOC_UCONTEXT_RESP_MASK_DUMP_FILL_MKEY    = 1UL << 1,
        MLX5_IB_ALLOC_UCONTEXT_RESP_MASK_ECE               = 1UL << 2,
+       MLX5_IB_ALLOC_UCONTEXT_RESP_MASK_REAL_TIME_TS      = 1UL << 4,
 };
 
 enum mlx5_user_cmds_supp_uhw {
@@ -270,6 +271,7 @@ struct mlx5_ib_query_device_resp {
 enum mlx5_ib_create_cq_flags {
        MLX5_IB_CREATE_CQ_FLAGS_CQE_128B_PAD    = 1 << 0,
        MLX5_IB_CREATE_CQ_FLAGS_UAR_PAGE_INDEX  = 1 << 1,
+       MLX5_IB_CREATE_CQ_FLAGS_REAL_TIME_TS    = 1 << 2,
 };
 
 struct mlx5_ib_create_cq {