RDMA/mlx5: Reorder calls to pcie_relaxed_ordering_enabled()

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.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Aharon Landau <[e-mail]>
Signed-off-by: Leon Romanovsky <[e-mail]>
Signed-off-by: Jason Gunthorpe <[e-mail]>

drivers/infiniband/hw/mlx5/mr.c

···
 					  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));
···
 	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);