Re: [PATCH 1/2] Documentation: dmaengine: Add a description of what dmatest does

From: Daniel Thompson
Date: Thu Aug 19 2021 - 05:13:40 EST


On Wed, Aug 18, 2021 at 06:27:52PM +0300, Andy Shevchenko wrote:
> On Wed, Aug 18, 2021 at 6:15 PM Daniel Thompson
> <daniel.thompson@xxxxxxxxxx> wrote:
> >
> > Currently it can difficult to determine what dmatest does without
> > reading the source code. Let's add a description.
> >
> > The description is taken mostly from the patch header of
> > commit 4a776f0aa922 ("dmatest: Simple DMA memcpy test client")
> > although it has been edited and updated slightly.
>
> > Signed-off-by: Haavard Skinnemoen <hskinnemoen@xxxxxxxxx>
>
> Not sure if you can use it like this (I mean the above SoB)

I wondered about that.

In the end I concluded that if I had picked up code from an old patch
and edited to this degree then I would probably consider it a new
patch but be clear about credit and preserve the original SoB. I saw no
real reason to treat the contents of a patch header much different.

However, I'm very happy to make the credit more informal if needed.

> Otherwise it's a good idea, thanks!
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

Thanks!


Daniel.


>
> > Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
> > ---
> > Documentation/driver-api/dmaengine/dmatest.rst | 10 ++++++++++
> > 1 file changed, 10 insertions(+)
> >
> > diff --git a/Documentation/driver-api/dmaengine/dmatest.rst b/Documentation/driver-api/dmaengine/dmatest.rst
> > index ee268d445d38..529cc2cbbb1b 100644
> > --- a/Documentation/driver-api/dmaengine/dmatest.rst
> > +++ b/Documentation/driver-api/dmaengine/dmatest.rst
> > @@ -6,6 +6,16 @@ Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> >
> > This small document introduces how to test DMA drivers using dmatest module.
> >
> > +The dmatest module tests DMA memcpy, memset, XOR and RAID6 P+Q operations using
> > +various lengths and various offsets into the source and destination buffers. It
> > +will initialize both buffers with a repeatable pattern and verify that the DMA
> > +engine copies the requested region and nothing more. It will also verify that
> > +the bytes aren't swapped around, and that the source buffer isn't modified.
> > +
> > +The dmatest module can be configured to test a specific channel. It can also
> > +test multiple channels at the same time, and it can start multiple threads
> > +competing for the same channel.
> > +
> > .. note::
> > The test suite works only on the channels that have at least one
> > capability of the following: DMA_MEMCPY (memory-to-memory), DMA_MEMSET
> > --
> > 2.30.2
> >
>
>
> --
> With Best Regards,
> Andy Shevchenko