[dpdk-dev] [PATCH v10] dmadev: introduce DMA device library

[fengchengwen]

Thanks

The first two point (STATUS_UNKNOWN->STATUS_ERROR_UNKNOWN, INVALID_ADDR) already
fix in V11.

@Burce @Jerin @Morten
In addition, programming guide is added in v11, please take a look, thanks.


On 2021/7/26 16:31, Bruce Richardson wrote:
> On Mon, Jul 26, 2021 at 02:53:16PM +0800, fengchengwen wrote:
>> Friendly ping.
>>
>> On 2021/7/20 20:46, Chengwen Feng wrote:
>>> This patch introduce 'dmadevice' which is a generic type of DMA
>>> device.
>>>
>>> The APIs of dmadev library exposes some generic operations which can
>>> enable configuration and I/O with the DMA devices.
>>>
>>> Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
>>> ---
>>> v10:
>>> * fix rte_dmadev_completed_status comment.
>>
>> [snip]
> 
> I'm still working through porting over our driver(s) to the latest revisions,
> and digging into the details of the error handling and approaches, looking
> for any issues. For now, a couple of small suggestions and ideas:
> 
> * for the STATUS_UNKNOWN value, I think it should be renamed to
>   ERROR_UNKNOWN since this is an error value. Alternatively, add a new
>   "UNKNOWN_ERROR" entry in the list to cover this possibility i.e. we know
>   status is an error, just not exactly what the error is.
> 
> * While we have errors for both invalid source or invalid destination
>   addresses, I think we also should add a slightly more general error code
>   for "INVALID_ADDR" to cover the case where one is bad but we are not sure
>   which.
> 
> * Not sure exactly how to handle this, but I suspect we may need some sort
>   of capability flag to cover behaviour on hitting an error. For HW using
>   our original ioat driver, the jobs are done strictly in order and the HW
>   will halt on error, while with hardware using newer idxd driver, things are
>   done potentially out-of-order and other jobs continue after the failed
>   job. I will come back with a more concrete proposal on this later, once I
>   get both drivers up and working. I suspect we will encounter more
>   edge-cases like this as people work on drivers.
> 
> Overall, functionally this patchset looks pretty good to me. One thing
> that will be needed for merge into mainline is a chapter on dmadev for the
> programmers guide document, plus any other necessary doc updates such as a
> good release-note update for this new lib.
> 
> For what is here now though,
> 
> Acked-by: Bruce Richardson <bruce.richardson at intel.com>
> 
> .
>