[PATCH rdma-next 5/7] RDMA/mlx5: Reorder calls to pcie_relaxed_ordering_enabled()

Leon Romanovsky
2021-12-06T09:12:20Z

The mkc is the key for the mkey cache, hence, created in each attempt to
get a cache mkey, while pcie_relaxed_ordering_enabled() is called during
the setting of the mkc, but used only for cases where IB_ACCESS_RELAXED_ORDERING
is set.

pcie_relaxed_ordering_enabled() is an expensive call (26 us). Reorder the
code so the driver will call it only when it is needed.

Signed-off-by: Aharon Landau <aharonl@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
drivers/infiniband/hw/mlx5/mr.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
index 6000acbedc73..ca6faf599cd3 100644
--- a/drivers/infiniband/hw/mlx5/mr.c
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -68,7 +68,6 @@ static void set_mkc_access_pd_addr_fields(void *mkc, int acc, u64 start_addr,
struct ib_pd *pd)
{
struct mlx5_ib_dev *dev = to_mdev(pd->device);
- bool ro_pci_enabled = pcie_relaxed_ordering_enabled(dev->mdev->pdev);

MLX5_SET(mkc, mkc, a, !!(acc & IB_ACCESS_REMOTE_ATOMIC));
MLX5_SET(mkc, mkc, rw, !!(acc & IB_ACCESS_REMOTE_WRITE));
@@ -76,12 +75,13 @@ static void set_mkc_access_pd_addr_fields(void *mkc, int acc, u64 start_addr,
MLX5_SET(mkc, mkc, lw, !!(acc & IB_ACCESS_LOCAL_WRITE));
MLX5_SET(mkc, mkc, lr, 1);

- if (MLX5_CAP_GEN(dev->mdev, relaxed_ordering_write))
- MLX5_SET(mkc, mkc, relaxed_ordering_write,
- (acc & IB_ACCESS_RELAXED_ORDERING) && ro_pci_enabled);
- if (MLX5_CAP_GEN(dev->mdev, relaxed_ordering_read))
- MLX5_SET(mkc, mkc, relaxed_ordering_read,
- (acc & IB_ACCESS_RELAXED_ORDERING) && ro_pci_enabled);
+ if ((acc & IB_ACCESS_RELAXED_ORDERING) &&
+ pcie_relaxed_ordering_enabled(dev->mdev->pdev)) {
+ if (MLX5_CAP_GEN(dev->mdev, relaxed_ordering_write))
+ MLX5_SET(mkc, mkc, relaxed_ordering_write, 1);
+ if (MLX5_CAP_GEN(dev->mdev, relaxed_ordering_read))
+ MLX5_SET(mkc, mkc, relaxed_ordering_read, 1);
+ }

MLX5_SET(mkc, mkc, pd, to_mpd(pd)->pdn);
MLX5_SET(mkc, mkc, qpn, 0xffffff);
--
2.33.1