lkml.org 
[lkml]   [2021]   [Oct]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH for-next 0/3] EFA dmabuf memory regions
    On Tue, Oct 12, 2021 at 03:09:00PM +0300, Gal Pressman wrote:
    > Hey all,
    >
    > This is a followup to my previous RFCs [1][2], which now adds a new api
    > to the RDMA subsystem that allows drivers to get a pinned dmabuf memory
    > region without requiring an implementation of the move_notify callback.
    > The new api makes use of the dynamic attachment api implemented in the
    > RDMA subsystem, but calls dma_buf_pin() in order to make sure that the
    > callback will not be called, as suggested by Christian.
    >
    > As explained in the previous RFC, move_notify requires the RDMA device
    > to support on-demand-paging (ODP) which is not common on most devices
    > (only supported by mlx5).
    >
    > While the dynamic requirement makes sense for certain GPUs, some devices
    > (such as habanalabs) have device memory that is always "pinned" and do
    > not need/use the move_notify operation.
    >
    > Patch #1 changes the dmabuf documentation to make it clear that pinning
    > does not necessarily mean the memory must be moved to system memory, it
    > is up to the exporter to decide.
    > Patch #2 adds the RDMA api that allows drivers to get pinned dmabuf
    > memory regions.
    > Patch #3 adds the EFA implementation of the dmabuf importer.
    >
    > The motivation of this submission is to use habanalabs as the dmabuf
    > exporter, and EFA as the importer to allow for peer2peer access through
    > libibverbs.
    >
    > [1] https://lore.kernel.org/linux-rdma/20210818074352.29950-1-galpress@amazon.com/
    > [2] https://lore.kernel.org/linux-rdma/20211007104301.76693-1-galpress@amazon.com/
    >
    > Thanks
    >
    > Gal Pressman (3):
    > dma-buf: Fix pin callback comment
    > RDMA/umem: Allow pinned dmabuf umem usage
    > RDMA/efa: Add support for dmabuf memory regions

    Applied to for-next, thanks

    Jason

    \
     
     \ /
      Last update: 2021-10-27 16:53    [W:2.635 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site