From d9e6e85b7beb2aeb8defac2f705b23532ddb25d4 Mon Sep 17 00:00:00 2001 From: Yishai Hadas Date: Wed, 13 Aug 2025 15:36:01 +0300 Subject: [PATCH] RDMA/mlx5: Enable Data-Direct with Relaxed Ordering Relaxed Ordering can improve performance in certain scenarios. Enable it in the Data-Direct use case as well. Link: https://patch.msgid.link/r/1221dcdda8061ba5f6bc3519044083c7438b257e.1755088503.git.leon@kernel.org Signed-off-by: Yishai Hadas Reviewed-by: Gal Shalom Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe --- drivers/infiniband/hw/mlx5/main.c | 32 ++++++++++++++++++++++++++-- drivers/infiniband/hw/mlx5/mlx5_ib.h | 2 ++ drivers/infiniband/hw/mlx5/mr.c | 8 +++---- drivers/infiniband/hw/mlx5/umr.c | 6 +++++- 4 files changed, 41 insertions(+), 7 deletions(-) diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c index d456e4fde3e1..505349c68e79 100644 --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -3118,6 +3118,7 @@ mlx5_ib_create_data_direct_resources(struct mlx5_ib_dev *dev) { int inlen = MLX5_ST_SZ_BYTES(create_mkey_in); struct mlx5_core_dev *mdev = dev->mdev; + bool ro_supp = false; void *mkc; u32 mkey; u32 pdn; @@ -3146,14 +3147,37 @@ mlx5_ib_create_data_direct_resources(struct mlx5_ib_dev *dev) MLX5_SET(mkc, mkc, length64, 1); MLX5_SET(mkc, mkc, qpn, 0xffffff); err = mlx5_core_create_mkey(mdev, &mkey, in, inlen); - kvfree(in); if (err) - goto err; + goto err_mkey; dev->ddr.mkey = mkey; dev->ddr.pdn = pdn; + + /* create another mkey with RO support */ + if (MLX5_CAP_GEN(dev->mdev, relaxed_ordering_write)) { + MLX5_SET(mkc, mkc, relaxed_ordering_write, 1); + ro_supp = true; + } + + if (MLX5_CAP_GEN(dev->mdev, relaxed_ordering_read)) { + MLX5_SET(mkc, mkc, relaxed_ordering_read, 1); + ro_supp = true; + } + + if (ro_supp) { + err = mlx5_core_create_mkey(mdev, &mkey, in, inlen); + /* RO is defined as best effort */ + if (!err) { + dev->ddr.mkey_ro = mkey; + dev->ddr.mkey_ro_valid = true; + } + } + + kvfree(in); return 0; +err_mkey: + kvfree(in); err: mlx5_core_dealloc_pd(mdev, pdn); return err; @@ -3162,6 +3186,10 @@ err: static void mlx5_ib_free_data_direct_resources(struct mlx5_ib_dev *dev) { + + if (dev->ddr.mkey_ro_valid) + mlx5_core_destroy_mkey(dev->mdev, dev->ddr.mkey_ro); + mlx5_core_destroy_mkey(dev->mdev, dev->ddr.mkey); mlx5_core_dealloc_pd(dev->mdev, dev->ddr.pdn); } diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h index 7ffc7ee92cf0..309f256fc27d 100644 --- a/drivers/infiniband/hw/mlx5/mlx5_ib.h +++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h @@ -854,6 +854,8 @@ struct mlx5_ib_port_resources { struct mlx5_data_direct_resources { u32 pdn; u32 mkey; + u32 mkey_ro; + u8 mkey_ro_valid :1; }; struct mlx5_ib_resources { diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c index 1317f2cb38a4..d3c82ffa300e 100644 --- a/drivers/infiniband/hw/mlx5/mr.c +++ b/drivers/infiniband/hw/mlx5/mr.c @@ -1717,11 +1717,11 @@ reg_user_mr_dmabuf_by_data_direct(struct ib_pd *pd, u64 offset, goto end; } - /* The device's 'data direct mkey' was created without RO flags to - * simplify things and allow for a single mkey per device. - * Since RO is not a must, mask it out accordingly. + /* If no device's 'data direct mkey' with RO flags exists + * mask it out accordingly. */ - access_flags &= ~IB_ACCESS_RELAXED_ORDERING; + if (!dev->ddr.mkey_ro_valid) + access_flags &= ~IB_ACCESS_RELAXED_ORDERING; crossed_mr = reg_user_mr_dmabuf(pd, &data_direct_dev->pdev->dev, offset, length, virt_addr, fd, access_flags, MLX5_MKC_ACCESS_MODE_KSM, diff --git a/drivers/infiniband/hw/mlx5/umr.c b/drivers/infiniband/hw/mlx5/umr.c index 7ef35cddce81..4e562e0dd9e1 100644 --- a/drivers/infiniband/hw/mlx5/umr.c +++ b/drivers/infiniband/hw/mlx5/umr.c @@ -761,7 +761,11 @@ _mlx5r_umr_update_mr_pas(struct mlx5_ib_mr *mr, unsigned int flags, bool dd, if (dd) { cur_ksm->va = cpu_to_be64(rdma_block_iter_dma_address(&biter)); - cur_ksm->key = cpu_to_be32(dev->ddr.mkey); + if (mr->access_flags & IB_ACCESS_RELAXED_ORDERING && + dev->ddr.mkey_ro_valid) + cur_ksm->key = cpu_to_be32(dev->ddr.mkey_ro); + else + cur_ksm->key = cpu_to_be32(dev->ddr.mkey); if (mr->umem->is_dmabuf && (flags & MLX5_IB_UPD_XLT_ZAP)) { cur_ksm->va = 0; -- 2.47.3