Re: [PATCH v5 0/7] dmaengine: Support polling for out of order completions

[Dave Jiang <dave.jiang@intel.com>]

On 8/29/2022 1:35 PM, Ben Walker wrote:
> This series adds support for polling async transactions for completion
> even if interrupts are disabled and transactions can complete out of
> order.
>
> Prior to this series, dma_cookie_t was a monotonically increasing integer and
> cookies could be compared to one another to determine if earlier operations had
> completed (up until the cookie wraps around, then it would break). Now, cookies
> are treated as opaque handles. The series also does some API clean up and
> documents how dma_cookie_t should behave.
>
> This closes out by adding support for .device_tx_status() to the idxd
> driver and then reverting the DMA_OUT_OF_ORDER patch that previously
> allowed idxd to opt-out of support for polling, which I think is a nice
> overall simplification to the dmaengine API.
>
> Changes since version 4:
>   - Rebased
>   - Removed updates to the various drivers that call dma_async_is_tx_complete.
>     These clean ups will be spun off into a separate patch series since they need
>     acks from other maintainers.
>
> Changes since version 3:
>   - Fixed Message-Id in emails. Sorry they were all stripped! Won't
>     happen again.
>
> Changes since version 2:
>   - None. Rebased as requested without conflict.
>
> Changes since version 1:
>   - Broke up the change to remove dma_async_is_tx_complete into a single
>     patch for each driver
>   - Renamed dma_async_is_tx_complete to dmaengine_async_is_tx_complete.
>
> Ben Walker (7):
>    dmaengine: Remove dma_async_is_complete from client API
>    dmaengine: Move dma_set_tx_state to the provider API header
>    dmaengine: Add dmaengine_async_is_tx_complete
>    dmaengine: Add provider documentation on cookie assignment
>    dmaengine: idxd: idxd_desc.id is now a u16
>    dmaengine: idxd: Support device_tx_status
>    dmaengine: Revert "cookie bypass for out of order completion"
>
>   Documentation/driver-api/dmaengine/client.rst | 24 ++----
>   .../driver-api/dmaengine/provider.rst         | 64 ++++++++------
>   drivers/dma/dmaengine.c                       |  2 +-
>   drivers/dma/dmaengine.h                       | 21 ++++-
>   drivers/dma/dmatest.c                         | 14 +--
>   drivers/dma/idxd/device.c                     |  1 +
>   drivers/dma/idxd/dma.c                        | 86 ++++++++++++++++++-
>   drivers/dma/idxd/idxd.h                       |  3 +-
>   include/linux/dmaengine.h                     | 43 +++-------
>   9 files changed, 164 insertions(+), 94 deletions(-)
Besides the stray white space, Reviewed-by: Dave Jiang 
<dave.jiang@gmail.com>