Scatter to CQE
Subsystems (5)
cover Scatter to CQE
From: Leon Romanovsky <[email protected]>
Quoted 1 line
From Yonatan,
Scatter to CQE is a HW offload feature that saves PCI writes by scattering the payload to the CQE.
The feature depends on the CQE size and if the CQE size is 64B, it will work for payload smaller than 32. If the CQE size is 128B, it will work for payload smaller than 64.
The feature works for responder and requestor:
1. For responder, if the payload is small as required above, the data will be part of the CQE, and thus we save another PCI transaction the recv buffers.
2. For requestor, this can be used to get the RDMA_READ response and RDMA_ATOMIC response in the CQE. This feature is already supported in upstream.
As part of this series, we are adding support for DC transport type and ability to enable the feature (force enable) in the requestor when SQ is not configured to signal all WRs.
Thanks
Yonatan Cohen (4):
net/mlx5: Expose DC scatter to CQE capability bit IB/mlx5: Support scatter to CQE for DC transport type IB/mlx5: Verify that driver supports user flags IB/mlx5: Allow scatter to CQE without global signaled WRs
drivers/infiniband/hw/mlx5/cq.c | 2 +- drivers/infiniband/hw/mlx5/mlx5_ib.h | 2 +- drivers/infiniband/hw/mlx5/qp.c | 91 ++++++++++++++++++++++++++++-------- include/linux/mlx5/mlx5_ifc.h | 3 +- include/uapi/rdma/mlx5-abi.h | 1 + 5 files changed, 77 insertions(+), 22 deletions(-)
PATCH 1/4 net/mlx5: Expose DC scatter to CQE capability bit
From: Yonatan Cohen <[email protected]>
dc_req_scat_data_cqe capability bit determines
if requester scatter to cqe is available for 64 bytes CQE over DC transport type.
--- include/linux/mlx5/mlx5_ifc.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
include/linux/mlx5/mlx5_ifc.h +2 -1
@@ -1005,7 +1005,8 @@ struct mlx5_ifc_cmd_hca_cap_bits {u8 umr_modify_atomic_disabled[0x1 ];u8 umr_indirect_mkey_disabled[0x1 ];u8 umr_fence[0x2 ]; -u8 reserved_at_20c[0x3 ]; +u8 dc_req_scat_data_cqe[0x1 ]; +u8 reserved_at_20d[0x2 ];u8 drain_sigerr[0x1 ];u8 cmdif_checksum[0x2 ];u8 sigerr_cqe[0x1 ];
Signature · 1 line
2.14.4
PATCH 2/4 IB/mlx5: Support scatter to CQE for DC transport type
In reply to Leon RomanovskyFrom: Yonatan Cohen <[email protected]>
Scatter to CQE is a HW offload that saves PCI writes by scattering the payload to the CQE.
This patch extends already existing functionality to support DC transport type.
--- drivers/infiniband/hw/mlx5/cq.c | 2 +- drivers/infiniband/hw/mlx5/mlx5_ib.h | 2 +- drivers/infiniband/hw/mlx5/qp.c | 71 ++++++++++++++++++++++++++---------- 3 files changed, 54 insertions(+), 21 deletions(-)
drivers/infiniband/hw/mlx5/cq.c +1 -1
@@ -1460,7 +1460,7 @@ int mlx5_ib_resize_cq(struct ib_cq *ibcq, int entries, struct ib_udata *udata)return err; } -int mlx5_ib_get_cqe_size (struct mlx5_ib_dev *dev,struct ib_cq *ibcq) +int mlx5_ib_get_cqe_size (struct ib_cq *ibcq) {struct mlx5_ib_cq *cq;
drivers/infiniband/hw/mlx5/mlx5_ib.h +1 -1
@@ -1127,7 +1127,7 @@ void __mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,void mlx5_ib_populate_pas (struct mlx5_ib_dev *dev,struct ib_umem *umem,int page_shift,__be64 *pas,int access_flags);void mlx5_ib_copy_pas (u64 *old,u64 *new,int step,int num); -int mlx5_ib_get_cqe_size (struct mlx5_ib_dev *dev,struct ib_cq *ibcq); +int mlx5_ib_get_cqe_size (struct ib_cq *ibcq);int mlx5_mr_cache_init (struct mlx5_ib_dev *dev);int mlx5_mr_cache_cleanup (struct mlx5_ib_dev *dev);
drivers/infiniband/hw/mlx5/qp.c +52 -19
101 lines not on this page · raw message
Signature · 1 line
2.14.4
PATCH 3/4 IB/mlx5: Verify that driver supports user flags
In reply to Leon RomanovskyFrom: Yonatan Cohen <[email protected]>
Flags sent down from user might not be supported by running driver.
This might lead to unwanted bugs.
To solve this, added macro to test for unsupported flags.
--- drivers/infiniband/hw/mlx5/qp.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
drivers/infiniband/hw/mlx5/qp.c +12 -0
@@ -1728,6 +1728,15 @@ static void configure_requester_scat_cqe(struct mlx5_ib_dev *dev,MLX5_SET (qpc, qpc, cs_req,MLX5_REQ_SCAT_DATA32_CQE ); } +#define MLX5_QP_CREATE_FLAGS_NOT_SUPPORTED (flags) \ + ((flags) & ~( \ + MLX5_QP_FLAG_SIGNATURE | \ + MLX5_QP_FLAG_SCATTER_CQE | \ + MLX5_QP_FLAG_TUNNEL_OFFLOADS | \ + MLX5_QP_FLAG_BFREG_INDEX | \ + MLX5_QP_FLAG_TYPE_DCT | \ + MLX5_QP_FLAG_TYPE_DCI)) +static int create_qp_common (struct mlx5_ib_dev *dev,struct ib_pd *pd,struct ib_qp_init_attr *init_attr,struct ib_udata *udata,struct mlx5_ib_qp *qp)
@@ -1825,6 +1834,9 @@ static int create_qp_common(struct mlx5_ib_dev *dev, struct ib_pd *pd,return -EFAULT ; } +if (MLX5_QP_CREATE_FLAGS_NOT_SUPPORTED (ucmd.flags)) +return -EINVAL ; + err =get_qp_user_index (to_mucontext (pd->uobject->context), &ucmd, udata->inlen, &uidx);if (err)
Signature · 1 line
2.14.4
PATCH 4/4 IB/mlx5: Allow scatter to CQE without global signaled WRs
In reply to Leon RomanovskyFrom: Yonatan Cohen <[email protected]>
Requester scatter to CQE is restricted to QPs configured to signal all WRs.
This patch adds ability to enable scatter to cqe (force enable) in the requester without sig_all, for users who do not want all WRs signaled but rather just the ones whose data found in the CQE.
--- drivers/infiniband/hw/mlx5/qp.c | 14 +++++++++++--- include/uapi/rdma/mlx5-abi.h | 1 + 2 files changed, 12 insertions(+), 3 deletions(-)
drivers/infiniband/hw/mlx5/qp.c +11 -3
@@ -1706,15 +1706,20 @@ static void configure_responder_scat_cqe(struct ib_qp_init_attr *init_attr,static void configure_requester_scat_cqe (struct mlx5_ib_dev *dev,struct ib_qp_init_attr *init_attr, +struct mlx5_ib_create_qp *ucmd,void *qpc) {enum ib_qp_type qpt = init_attr->qp_type;int scqe_sz; +bool allow_scat_cqe =0 ;if (qpt ==IB_QPT_UC || qpt ==IB_QPT_UD )return ; -if (init_attr->sq_sig_type !=IB_SIGNAL_ALL_WR ) +if (ucmd) + allow_scat_cqe = ucmd->flags &MLX5_QP_FLAG_ALLOW_SCATTER_CQE ; + +if (!allow_scat_cqe && init_attr->sq_sig_type !=IB_SIGNAL_ALL_WR )return ; scqe_sz =mlx5_ib_get_cqe_size (init_attr->send_cq);
@@ -1735,7 +1740,8 @@ static void configure_requester_scat_cqe(struct mlx5_ib_dev *dev, MLX5_QP_FLAG_TUNNEL_OFFLOADS | \ MLX5_QP_FLAG_BFREG_INDEX | \ MLX5_QP_FLAG_TYPE_DCT | \ - MLX5_QP_FLAG_TYPE_DCI)) + MLX5_QP_FLAG_TYPE_DCI | \ + MLX5_QP_FLAG_ALLOW_SCATTER_CQE)) static int create_qp_common(struct mlx5_ib_dev *dev, struct ib_pd *pd, struct ib_qp_init_attr *init_attr,
@@ -1969,7 +1975,9 @@ static int create_qp_common(struct mlx5_ib_dev *dev, struct ib_pd *pd,if (qp->scat_cqe &&is_connected (init_attr->qp_type)) {configure_responder_scat_cqe (init_attr, qpc); -configure_requester_scat_cqe (dev, init_attr, qpc); +configure_requester_scat_cqe (dev, init_attr, + (pd && pd->uobject) ? &ucmd :NULL , + qpc); }if (qp->rq.wqe_cnt) {
include/uapi/rdma/mlx5-abi.h +1 -0
@@ -47,6 +47,7 @@ enum {MLX5_QP_FLAG_TYPE_DCI =1 <<5 ,MLX5_QP_FLAG_TIR_ALLOW_SELF_LB_UC =1 <<6 ,MLX5_QP_FLAG_TIR_ALLOW_SELF_LB_MC =1 <<7 , + MLX5_QP_FLAG_ALLOW_SCATTER_CQE = 1 << 8, }; enum {
Signature · 1 line
2.14.4
Re: [PATCH rdma-next 3/4] IB/mlx5: Verify that driver supports user flags
In reply to Leon RomanovskyQuoted 16 lines · Leon Romanovsky
From: Yonatan Cohen <[email protected]>
Flags sent down from user might not be supported by running driver.
This might lead to unwanted bugs.
To solve this, added macro to test for unsupported flags.Signed-off-by Yonatan Cohen <[email protected]>Signed-off-by Leon Romanovsky <[email protected]>drivers/infiniband/hw/mlx5/qp.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)drivers/infiniband/hw/mlx5/qp.c +1
-0+++ b/drivers/infiniband/hw/mlx5/qp.c
drivers/infiniband/hw/mlx5/qp.c static void configure_requester_scat_cqe(struct mlx5_ib_dev *dev, · line 1732
Quoted 5 lines
drivers/infiniband/hw/mlx5/qp.c +2
-0@@ -1728,6 +1728,15 @@ static void configure_requester_scat_cqe(struct mlx5_ib_dev *dev,MLX5_SET (qpc, qpc, cs_req,MLX5_REQ_SCAT_DATA32_CQE ); } +#define MLX5_QP_CREATE_FLAGS_NOT_SUPPORTED (flags) \ + ((flags) & ~( \
This needs a cast, it would be better to add something like the check comp mask function in rdma-core than this goofy macro thing.
Jason