Re: [PATCH 00/15] Rework the locking and datastructures for mlx5 implicit ODP

Jason Gunthorpe
2019-10-28T19:47:44Z

On Wed, Oct 09, 2019 at 01:09:20PM -0300, Jason Gunthorpe wrote:
> From: Jason Gunthorpe <jgg@mellanox.com>
>
> In order to hoist the interval tree code out of the drivers and into the
> mmu_notifiers it is necessary for the drivers to not use the interval tree
> for other things.
>
> This series replaces the interval tree with an xarray and along the way
> re-aligns all the locking to use a sensible SRCU model where the 'update'
> step is done by modifying an xarray.
>
> The result is overall much simpler and with less locking in the critical
> path. Many functions were reworked for clarity and small details like
> using 'imr' to refer to the implicit MR make the entire code flow here
> more readable.
>
> This also squashes at least two race bugs on its own, and quite possibily
> more that haven't been identified.
>
> Jason Gunthorpe (15):
> RDMA/mlx5: Use SRCU properly in ODP prefetch
> RDMA/mlx5: Split sig_err MR data into its own xarray
> RDMA/mlx5: Use a dedicated mkey xarray for ODP
> RDMA/mlx5: Delete struct mlx5_priv->mkey_table
> RDMA/mlx5: Rework implicit_mr_get_data
> RDMA/mlx5: Lift implicit_mr_alloc() into the two routines that call it
> RDMA/mlx5: Set the HW IOVA of the child MRs to their place in the tree
> RDMA/mlx5: Split implicit handling from pagefault_mr
> RDMA/mlx5: Use an xarray for the children of an implicit ODP
> RDMA/mlx5: Reduce locking in implicit_mr_get_data()
> RDMA/mlx5: Avoid double lookups on the pagefault path
> RDMA/mlx5: Rework implicit ODP destroy
> RDMA/mlx5: Do not store implicit children in the odp_mkeys xarray
> RDMA/mlx5: Do not race with mlx5_ib_invalidate_range during create and
> destroy
> RDMA/odp: Remove broken debugging call to invalidate_range

Applied to for-next with the two noted fixes

Jason